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1
Gu, Daifang, and O. M. Phillips. "On narrow V-like ship wakes." Journal of Fluid Mechanics 275 (September 25, 1994): 301–21. http://dx.doi.org/10.1017/s0022112094002375.
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This paper is concerned with the generation of short gravity waves and their radiation from the outer edge of the turbulent boundary layer and wake of a ship. They arise primarily near the ship's stern. The wave spectrum in the direction of wavenumber vector at an angle (90° – δ) to the ship's track is: \[\Phi_{\delta}(\omega) = \Psi\left(\frac{UT_d}{2l},\frac{U\sin\delta}{c_g},\frac{R}{UT_d}\right)\frac{1}{k_0R}\frac{2l\omega^2}{g^2}\gamma\left(0,\frac{\pi}{l};0,\omega \right),\] where Ψ is dimensionless and a function of three dimensionless parameters. γ is the spectrum of the oscillating motion at the boundary, U the ship speed, Td the decay timescale of the oscillating motion, 2l the lengthscale of the eddies, and R the distance away from the boundary along the wavenumber vector. Generally, Φδ has large values near δ = 0 and small values at large δ; it behaves as 1/R at distances not far from the ship, then may vary slower than 1/R at intermediate distances, and finally behaves as 1/R again at distances far from the ship. These are consistent with the pattern found in SAR images of narrow V-like ship wakes. The method developed here is also applicable to various problems of surface wave generation by turbulence in water.
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Bosser, Pierre, Olivier Bock, Cyrille Flamant, Sandrine Bony, and Sabrina Speich. "Integrated water vapour content retrievals from ship-borne GNSS receivers during EUREC<sup>4</sup>A." Earth System Science Data 13, no. 4 (April 12, 2021): 1499–517. http://dx.doi.org/10.5194/essd-13-1499-2021.
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Abstract. In the framework of the EUREC4A (Elucidating the role of clouds–circulation coupling in climate) campaign that took place in January and February 2020, integrated water vapour (IWV) contents were retrieved over the open tropical Atlantic Ocean using Global Navigation Satellite System (GNSS) data acquired from three research vessels (R/Vs): R/V Atalante, R/V Maria S. Merian and R/V Meteor. This paper describes the GNSS processing method and compares the GNSS IWV retrievals with IWV estimates from the European Centre for Medium-range Weather Forecasts (ECMWF) fifth reanalysis (ERA5), from the Moderate Resolution Imaging Spectroradiometer (MODIS) infrared products and from terrestrial GNSS stations located along the tracks of the ships. The ship-borne GNSS IWV retrievals from R/V Atalante and R/V Meteor compare well with ERA5, with small biases (−1.62 kg m−2 for R/V Atalante and +0.65 kg m−2 for R/V Meteor) and a root mean square (rms) difference of about 2.3 kg m−2. The results for the R/V Maria S. Merian are found to be of poorer quality, with an rms difference of 6 kg m−2, which is very likely due to the location of the GNSS antenna on this R/V prone to multipath effects. The comparisons with ground-based GNSS data confirm these results. The comparisons of all three R/V IWV retrievals with MODIS infrared products show large rms differences of 5–7 kg m−2, reflecting the enhanced uncertainties in these satellite products in the tropics. These ship-borne IWV retrievals are intended to be used for the description and understanding of meteorological phenomena that occurred during the campaign, east of Barbados, Guyana and northern Brazil. Both the raw GNSS measurements and the IWV estimates are available through the AERIS data centre (https://en.aeris-data.fr/, last access: 20 September 2020). The digital object identifiers (DOIs) for R/V Atalante IWV and raw datasets are https://doi.org/10.25326/71 (Bosser et al., 2020a) and https://doi.org/10.25326/74 (Bosser et al., 2020d), respectively. The DOIs for the R/V Maria S. Merian IWV and raw datasets are https://doi.org/10.25326/72 (Bosser et al., 2020b) and https://doi.org/10.25326/75 (Bosser et al., 2020e), respectively. The DOIs for the R/V Meteor IWV and raw datasets are https://doi.org/10.25326/73 (Bosser et al., 2020c) and https://doi.org/10.25326/76 (Bosser et al., 2020f), respectively.
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Murdani, Ni Ketut, and Anak Agung Elik Astari. "Pengaruh Volume Bongkar Dan Muat Barang Terhadap Volume Pendapatan Perusahaan PT. Varuna Tirta Prakasya (PERSERO) Di Pelabuhan Benoa Kabupaten Badung." Jurnal Ilmiah Satyagraha 2, no. 1 (June 8, 2020): 74–88. http://dx.doi.org/10.47532/jis.v2i1.56.
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KMP Nusa Jaya Abadi is primarily intended to connect the economic artery of Klungkung district in general and the island of Bali and small islands in Nusa Penida in particular. Since inaugurated its operation by the President of RI in 2007 until now the revenue from the port and shipping sectors served by Motor Vessel Penyebrangan Roro Nusa Jaya Abadi has reached more than 3.2 billion rupiah which consists of operational unit of loading and unloading goods and port charges.The purpose of this study is to know the analysis of loading and unloading of goods in increasing the Local Original Revenue (PAD) in the Port of Nusa Penida Distribution Klungkung regency.This research was conducted on Technical Implementation Unit of Port of Penpenangan Nusa Penida of Klungkung Regency. While the object of this research is the operational implementation of loading and unloading ship ports in an effort to increase local revenue (PAD).Data collection techniques include observation, interviews, and document recording. The method used in this research is quantitative analysis: correlation analysis, determination analysis, and t-test analysis.The results obtained from this research are: correlation analysis obtained correlation value (r) of = 0.9957, this means that the relationship between the independent variables of loading and unloading with the dependent variable Original Revenue has a correlation coefficient of 0.9957.From result of calculation of determination obtained result equal to 99,15%. This means that loading and unloading activities have an effect on increasing the original income of 99.15%, while the remaining 0.85% is the influence of other variables that are not measured in this study.While the results of t-test analysis obtained value of 10.7792 or (10.7792 6.3140), it can be said that the relationship that occurs between loading and unloading activities with the original revenue is significant (meaningful).
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Raineault, Nicole. "New Frontiers in Ocean Exploration: The E/V Nautilus, NOAA Ship Okeanos Explorer, and R/V Falkor 2019 Field Season." Oceanography 33, no. 1 (March 1, 2020): 1–122. http://dx.doi.org/10.5670/oceanog.2020.supplement.01.
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Bell, Katherine, and Nicole Raineault. "New Frontiers in Ocean Exploration: The E/V Nautilus, NOAA Ship Okeanos Explorer, and R/V Falkor 2016 Field Season." Oceanography 30, no. 1 (March 1, 2017): 1–94. http://dx.doi.org/10.5670/oceanog.2017.supplement.01.
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Raineault, Nicole. "New Frontiers in Ocean Exploration: The E/V Nautilus, NOAA Ship Okeanos Explorer, and R/V Falkor 2017 Field Season." Oceanography 31, no. 1 (March 1, 2018): 1–126. http://dx.doi.org/10.5670/oceanog.2018.supplement.01.
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CSCI, _. "CSCI Young Investigators Forum Abstracts." Clinical & Investigative Medicine 32, no. 4 (August 1, 2009): 1. http://dx.doi.org/10.25011/cim.v32i4.6623.
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ASSESSMENT OF PARALLEL SIGNALING PATHWAYS IN UTERINE MYOCYTES STIMULATED WITH VARIOUS SMOOTH MUSCLE AGONISTS H.N. Aguilar, B.F. Mitchell 1 TRACTOGRAPHY: A NOVEL TECHNIQUE TO IMAGE FIBER TRACTS OF THE SPINAL CORD Fahad Alkherayf, Eve Tsai, Arturo Cardenas-Blanco, Alain Berthiaume, Brien Benoit, John Sinclair 1 MODULATION OF OSTEOCLASTOGENESIS IN INFLAMMATORY JOINT DISEASES H. Allard-Chamard, M. Durant, A.J. de Brum-Fernandes, G. Boire, S.V. Komarova, S.J. Dixon, S.M. Sims, R. Harison, M.F. Manolson 2 “THE RIGHT THING TO DO? A CRITICAL ANALYSIS OF PUBLIC HEALTH ETHICS, RIGHTS DISCOURSE, AND THE EXPANSION OF ANTIRETROVIRAL THERAPY (ART)” Berkhout, SG, Anderson, S, Tyndall, MW 2 COST-EFFECTIVENESS OF IMMEDIATE BASELINE COMPUTED TOMOGRAPHY VS. MAGNETIC RESONANCE IMAGING OF ACUTE ISCHEMIC STROKE IN ONTARIO PATIENTS WHO PRESENT WITH SYMPTOMS SUGGESTIVE OF STROKE KR Burton, G. Mery 3 CHITOSAN-MEDIATED FGF18 DELIVERY FOR ASSISTED BONE REPAIR A. Carli, M. Lavertu, C. Gao, A. Merzouki, M.D. Buschmann, J.E. Henderson, E.J.Harvey 3 ACTIVE PI3K-AKT SIGNALING PROMOTES THE METASTATIC POTENTIAL OF ASCITES-DERIVED EPITHELIAL OVARIAN CANCER CELLS Correa RJM, Ramos-Valdes Y, Bertrand M, Lanvin D, Préfontaine M, Sugimoto AK, Lewis JD, Shepherd TG, DiMattia GE 4 MECHANISMS OF K65R, D67N, K103N, V106M AND M184V RESISTANCE DEVELOPMENT IN SUBTYPE-B AND C HIV-1 Dimitrios Coutsinos, Cedric F. Invernizzi, Daniela Moisi, Maureen Oliveira, Hongtao Xu, Bluma G. Brenner, Mark A. Wainberg 4 A MODEL TO DETERMINE FACTORS INVOLVED IN THE INDUCTION OF AN IN VIVO CTL RESPONSE Dissanayake D, Ohashi PS 5 P63 ANTAGONIZES P53 TO PROMOTE THE SURVIVAL OF EMBRYONIC NEURAL PRECURSOR CELLS Sagar B. Dugani, Annie Paquin, Masashi Fujitani, David R. Kaplan, Freda D. Miller 5 SPINAL LOCOMOTOR NETWORK MODULATION BY ENDOGENOUS SEROTONIN IN THE ISOLATED NEONATAL MOUSE SPINAL CORD Dunbar MJ, Whelan PJ 6 THE TUMOR PROMOTING AND REPRESSING EFFECTS OF INTEGRIN-LINKED KINASE ARE DIFFERENTIATED BY JNK1 IN HUMAN CANCER CELLS Adam David Durbin, Gregory Edward Hannigan, David Malkin 6 INCREASED EXCITATION IN MICE OVER-EXPRESSING NEUROLIGIN-1 IS ASSOCIATED WITH IMPAIRED LONG-TERM POTENTIATION AND LEARNING AND MEMORY Brennan D Eadie, Timal Kannangara, Regina Dalhaus, Rochelle M Hines, Yu-Tian Wang, Alaa El-Husseini, Brian R Christie 7 A NOVEL ROLE FOR CDK5/P35 IN MEDULLOBLASTOMA FORMATION Friesen AN, Shin J, Law V, Lee YS, Mckinnon P, Lee KY 7 ALTERED PSYCHOSOCIAL BEHAVIOUR AND STRESS RESPONSE FOLLOWING ‘MINOR’ STROKE IN THE RAT Krista Hewlett, Meighan Kelly, Dale Corbett 8 TUMOUR PATHOLOGY PREDICTS MICROSATELLITE INSTABILITY IN COLORECTAL CANCER AJ Hyde, D Fontaine, S Stuckless, RC Green, A Pollett, M Simms, P Parfrey, HB Younghusband 8 PROTEINASE-ACTIVATED RECEPTOR-2 (PAR2) IS A POTENTIAL TARGET FOR THE ANTI-INFLAMMATORY EFFECTS OF INSULIN Eric Hyun, Rithwick Ramachandran, Nicolas Cenac, Steeve Houle, Amit Saxena, Roland S. Liblau, Morley Hollenberg, Nathalie Vergnolle 9 CHEMOSENSITIVE PROPERTIES OF THE VENTRAL MEDULLA IN VITRO Kalf Daniel J, Wilson Richard JA 9 NOVEL DOPAMINE RECEPTOR-N TYPE CALCIUM CHANNEL INTERACTIONS: POTENTIAL THERAPEUTIC TARGETS FOR DISORDERS ASSOCIATED WITH ABERRANT DOPAMINERGIC SIGNALLING Alexandra E. Kisilevsky, Sean J. Mulligan, Christophe Altier, Mircea C. Iftinca, Diego Varela, Chao Tai, Lina Chen, Shahid Hameed, Jawed Hamid, Brian A. MacVicar, Gerald W. Zamponi 10 TRUNCATION OF THE C-TERMINAL DOMAIN OF CONNEXIN43 INCREASES INFARCT VOLUME DURING STROKE Kozoriz MG, Bechberger JF, Bechberger GR, Suen MWH, Moreno AP, Maass K, Willecke K, Naus CC 10 EVALUATION OF THE DELIVERABILITY AND TOLERABILITY OF INTENSIVE WEEKLY DOUBLET ADJUVANT CHEMOTHERAPY IN NON SMALL CELL LUNG CANCER M. Sara Kuruvilla, Lorraine Martelli-Reid, J. R. Goffin, A. Arnold, Peter M. Ellis 11 A POLICY-ORIENTED SYSTEMATIC REVIEW OF THE SAFETY AND EFFICACY OF ENDOSCOPIC THERAPIES FOR THE TREATMENT OF BARRETT’S ESOPHAGUS Lau D, Menon D, Stafinski T, Topfer LA, Walker J 11 THE SRC-LIKE ADAPTOR PROTEIN, SLAP, PLAYS A ROLE IN MONOCYTE-DERIVED DENDRITIC CELL MATURATION Larissa Liontos, L Dragone, A Weiss, C J McGlade 12 SWEET PEE: A NEW MOUSE MODEL FOR GLOMERULOCYSTIC KIDNEY DISEASE AND GLUCOSURIA J Ly, J Rossant, L Oxborne, C McKerlie, A Flenniken, S Quaggin 12 CARDIOGENIC SHOCK IN ASPHYXIATED NEONATE PIGLETS: IS COMBINATION INOTROPE THERAPY BETTER THAN HIGH-DOSE DOPAMINE? N. Manouchehri, P.-Y. Cheung, C. Joynt, T. Churchill, D. Bigam 13 THE RELATIONSHIP BETWEEN FLOW-MEDIATED DILATION, HYPEREMIC SHEAR STRESS, AND VARIOUS ANTHROPOMETRIC INDICES OF OBESITY Martin BJ, Title LM, Verma S, Charbonneau F, Buithieu J, Lonn EM, Anderson TJ 13 RAPID LOCALIZATION OF NEUTROPHILS TO SITES OF CELL DEATH BY MAC1-DEPENDENT ADHESION AND INTRAVASCULAR CRAWLING McDonald B, Menezes GB, Kubes P 14 THE ROLE OF SHIP-1 IN CEACAM1-MEDIATED HOST RESPONSES TO NEISSERIA GONORRHOEAE INFECTION Gordon G McSheffrey, S D Gray-Owen 14 USING VOLTAGE-SENSITIVE DYES TO RECORD BRAIN ACTIVITY IN NATURALLY MOVING MICE McVea DA, Mohajerani MH, Fingas M, Murphy TH 15 POTENTIAL MECHANICAL INFLUENCE IN MICROVASCULAR PATHOLOGY IN THE ACL DEFICIENT RABBIT KNEE Daniel Miller 15 OSTEOBLAST MECHANOSENSITIVITY: THE ROLE OF HYDROSTATIC PRESSURE Kenneth A. Myers, Timothy Douglas, Ricarda Hess, Justin Parreno, Jerome B. Rattner, Dieter Scharnweber, Nigel G. Shrive, David A. Hart 16 ENDOTHELIAL PROGENITOR CELLS FOR HEALING AND ANGIOGENESIS IN A SEGMENTAL BONE DEFECT MODEL: A COMPARISON WITH MESENCHYMAL STEM CELLS Nauth A, Li R, Schemitsch EH 16 DELAY OF DNA METHYLATION IN PERINATAL MALE GERM CELLS IN THE ABSENCE OF DNMT3L RESULTING IN INFERTILITY Kirsten Niles, Sophie La Salle, Christopher Oakes, Jacquetta Trasler 17 INVESTIGATING CRMP4 FUNCTION IN CNS NERVE REGENERATION S. Ong Tone, S. Kanagal, A. Wilson, Y.Z. Alabed, A. Di Polo, A.E. Fournier 17 A NOVEL, DNA DAMAGE-DEPENDENT REGULATORY PATHWAY FOR AKT IN VIVO Andrew J. Perrin, W. Brent Derry 18 CHOP AS A TARGET FOR PRESERVATION OF TRANSPLANTED ISLET GRAFT MASS Potter K, Dai L, Verchere CB 18 TREATMENT OF ACHILLES TENDINOPATHY R Ram, C Patel, D Wiseman, W Meeuwisse, JP Wiley 19 PLACENTAL LACTOGEN FUNCTION IN POST-IMPLANTATION MURINE PREGNANCY Saara M. Rawn, James C. Cross 19 DECODING NEURAL SIGNALS FROM MULTIELECTRODE ARRAYS IN THE PRIMATE DORSOLATERAL PREFRONTAL CORTEX Sachs A.J, Pieper F, Martinez-Trujillo J.C. 20 THE ROLE OF TRANSFORMING GROWTH FACTOR ALPHA IN A MOUSE MODEL OF OSTEOARTHRITIS Usmani S.E, Appleton C.T.G., Welch I.D, Beier F. 20 SKIN-DERIVED STEM CELLS ACT AS FUNCTIONAL SCHWANN CELLS WHEN TRANSPLANTED INTO LESIONED PERIPHERAL NERVE Sarah K. Walsh, Rajiv Midha 21 TLR4 MEDIATES SUSCEPTIBILITY TO STREPTOZOTOCIN-INDUCED DIABETES C Westwell-Roper, G Soukhatcheva, MJH Hutton, JP Dutz, CB Verchere 21 A FUSION OF GMCSF AND IL-21 (GIFT-21) POTENTLY INDUCES INFLAMMATION AND APOPTOSIS THROUGH SIGNALS DOWNSTREAM OF THE IL-21R ALPHA CHAIN Patrick Williams, Shala Yuan, Jessica Cuerquis, Elena Birman, Kathy Ann Forner, Jacques Galipeau 22
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Tomera, Mirosław. "Dynamic Positioning System for a Ship on Harbour Manoeuvring with Different Observers. Experimental Results." Polish Maritime Research 21, no. 3 (October 28, 2014): 13–24. http://dx.doi.org/10.2478/pomr-2014-0025.
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Abstract In cases when the navigational space of the manoeuvre performed by the ship is severely limited, the procedures making use of the rudder blade, propeller screw, and thrusters are very complicated. Such situations take place when the ship manoeuvres inside the harbour area and in those cases the structure of the control system is very complex. Te article describes the algorithm of multivariable control of ship motion over the water surface, which makes use of the state vector consisting of 6 variables. Tree of them, which are the position coordinates (x, y) measured by the DGPS system and the ship heading y measured by gyro-compass, were obtained experimentally. Te three remaining variables, which are the velocities in surge u, sway v, and yaw r directions, were estimated by Kalman filter, Kalman-Bucy filter and extended Kalman flter, respectively. The control algorithms making use of these observers were examined using the training ship “Blue Lady” which was navigated on the lake Silm in Ilawa/Kamionka in the Ship Handling Research and Training Centre owned by the Foundation for Safety of Navigation and Environment Protection. Te experimental results obtained using control systems with three observers were finally compared between each other.
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Bell, Robin E., and A. B. Watts. "Evaluation of the BGM-3 sea gravity meter system onboard R/V Conrad." GEOPHYSICS 51, no. 7 (July 1986): 1480–93. http://dx.doi.org/10.1190/1.1442196.
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The first Bell Aerospace BGM-3 Marine Gravity Meter System available for academic use was installed on R/V Robert D. Conrad in February, 1984. The BGM-3 system consists of a forced feedback accelerometer mounted on a gyrostabilized platform. Its sensor (requiring no cross‐coupling correction) is a significant improvement over existing beam and spring‐type sea gravimeters such as the GSS-2. A gravity survey over the Wallops Island test range together with the results of subsequent cruises allow evaluation of the precision, accuracy, and capabilities of the new system. Over the test range, the BGM-3 data were compared directly to data obtained by a GSS-2 meter onboard R/V Conrad. The rms discrepancy between free‐air gravity anomaly values at intersecting ship tracks of R/V Conrad was ±0.38 mGal for BGM-3 compared to ±1.60 mGal for the GSS-2. Moreover, BGM-3’s platform recovered from abrupt changes in ship’s heading more rapidly than did the platform of GSS-2. The principal factor limiting the accuracy of sea gravity data is navigation. Over the test range, where navigation was by Loran C and transit satellite, a two‐step filtering of the ship’s velocity and position was required to obtain an optimal Eötvös correction. A spectral analysis of 1 minute values of the Eötvös correction and the reduced free‐air gravity anomaly determined the filter characteristics. To minimize the coherence between the Eötvös and free‐air anomaly, it was necessary to prefilter the ship’s position and velocity. Using this procedure, reduced free‐air gravity anomalies with wavelengths as small as a few kilometers can be resolved.
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GOULIELMOS, ALEXANDER M., and EFTICHIA SIROPOULOU. "DETERMINING THE DURATION OF CYCLES IN THE MARKET OF SECOND-HAND TANKER SHIPS, 1976–2001: IS PREDICTION POSSIBLE?" International Journal of Bifurcation and Chaos 16, no. 07 (July 2006): 2119–27. http://dx.doi.org/10.1142/s0218127406015969.
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In this paper we have calculated the duration of cycles manifested in the prices of second-hand tanker ships, using the method of Rescale Range (R/S) Analysis. We have considered a time series of 312 monthly data, taken between the years 1976–2001, and combined R/S with a study of its V-statistic, Power Spectrum Analysis and Sharpe Ratio. Our ultimate goal is to be able to help decision-makers use this analysis in order to buy or sell a ship at the "best timing". As the sale and purchase ship market exhibits a strongly deterministic cyclical behavior with a high degree of "irregularity" (or "volatility"), we expect the techniques of Nonlinear Dynamics and Chaos Theory to be appropriate to be applied to its dynamics. We have found evidence for the existence of two cycles of tanker ship prices, of duration 4 and 8 years respectively, in the years 1976–2001, in agreement with what is expected from the theoretical analysis of freight market cycles. We have shown that our time series is not a random walk process and have used software prediction methods to demonstrate that short term forecasting of second-hand tanker prices may indeed be possible. These results are, of course, preliminary since a lot more data is needed to test their forecasting validity and hence should only be regarded as a start in this interesting area of research.
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Foster, James, Ning Li, and Kwok Fai Cheung. "Sea State Determination from Ship-Based Geodetic GPS." Journal of Atmospheric and Oceanic Technology 31, no. 11 (November 2014): 2556–64. http://dx.doi.org/10.1175/jtech-d-13-00211.1.
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AbstractOcean waves have a profound impact on navigation, offshore operations, recreation, safety, and the economic vitality of a nation’s maritime and coastal communities. This study demonstrates that ships equipped with geodetic GPS and a radar gauge can provide accurate estimates of sea state. The Research Vessel (R/V) Kilo Moana recorded 1-Hz data for the entire period of a 10-day cruise around the Hawaiian Islands. Solving for precise kinematic positions for the ship and combining these solutions with the ranges from the ship to the sea surface provided by the radar gauge, it was possible to retrieve 1-Hz estimates of the sea surface elevation along the cruise track. Converting these into estimates of significant wave height, strong agreement was found with wave buoy measurements and hindcast wave data. Comparison with buoy data indicates the estimates have errors on the order of 0.22 m, or less than 11% of the wave height. Using wave model predictions of the dominant directions, the data were processed further to correct for the Doppler shift and to estimate the dominant wave period. Although relatively noisy in locations where the predicted wave directions are expected to be poor, in general these estimates also show a good agreement with the wave buoy observations and hindcast wave estimates. A segment of the cruise that formed a circuit allowed for testing the consistency of the ship-based estimates and for determining a dominant wave direction, which was found to agree closely with model predictions.
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Genrich, J. F., and J. ‐B Minster. "Ship navigation for geophysical applications using Kalman‐filtered GPS fixes." GEOPHYSICS 56, no. 12 (December 1991): 1961–70. http://dx.doi.org/10.1190/1.1443007.
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Based on a state vector representation of ship position and velocity, we have developed a Kalman filter that provides accurate navigation from position fixes supplied by a Global Positioning System (GPS) receiver. Quasi‐constant position offsets occurring for fixes associated with switches in observed satellite constellation are modeled by including constellation biases as state vector components. A proper choice of statistics for state propagation and measurement noise leads to improved positioning. However, it may also increase the statistical dependence of Kalman estimates over characteristic time periods. Since a quantitative measure of this dependence is generally important for further processing, we have derived general expressions for the autocovariance of state vector Kalman estimates. These expressions contain products of propagation matrices and Kalman gains and, hence, relate directly to stability properties of the filter. For many applications, only certain components of the state vector are of interest. We show that autocovariances for state vector projections can be computed from corresponding projections of propagation matrices and Kalman gains, provided the state transition and measurement matrices satisfy certain reducibility conditions. Application of the filter and of the autocovariance expressions is illustrated using GPS and gravity measurements collected on board the Scripps Institution of Oceanography’s R/V Thomas Washington during Leg 1 of the Roundabout expedition.
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Sommariva, R., S. S. Brown, J. M. Roberts, D. M. Brookes, A. E. Parker, P. S. Monks, T. S. Bates, et al. "Ozone production in remote oceanic and industrial areas derived from ship based measurements of peroxy radicals during TexAQS 2006." Atmospheric Chemistry and Physics Discussions 10, no. 10 (October 7, 2010): 23109–47. http://dx.doi.org/10.5194/acpd-10-23109-2010.
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Abstract. During the Texas Air Quality Study II (TexAQS 2006) campaign, a PEroxy Radical Chemical Amplifier (PERCA) was deployed on the NOAA research vessel R/V Brown to measure total peroxy radicals (HO2+ΣRO2). Day-time mixing ratios of HO2+ΣRO2 between 25 and 110 ppt were observed throughout the study area – the Houston/Galveston region and the Gulf coast of the U.S. – and analyzed in relation to measurements of nitrogen oxides, volatile organic compounds (VOC) and photolysis rates to assess radical sources and sinks in the region. The measurements of HO2+ΣRO2 were used to calculate the in-situ net photochemical formation of ozone. Measured median values ranged from 0.6 ppb/h in clean oceanic air masses up to several tens of ppb/h in the most polluted industrial areas. The results are consistent with previous studies and generally agree with observations made during the previous TexAQS 2000 field campaign. The net photochemical ozone formation rates determined at Barbours Cut, a site immediately south of the Houston Ship Channel, were analyzed in relation to local wind direction and VOC reactivity to understand the relationship between ozone formation and local VOC emissions. The measurements of HO2+ΣRO2 made during the R/V Brown TexAQS 2006 cruise indicate that ozone formation is NOx-limited in the Houston/Galveston region and influenced by highly reactive hydrocarbons, especially alkenes from urban and industrial sources and their photooxidation products, such as formaldehyde.
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Sommariva, R., S. S. Brown, J. M. Roberts, D. M. Brookes, A. E. Parker, P. S. Monks, T. S. Bates, et al. "Ozone production in remote oceanic and industrial areas derived from ship based measurements of peroxy radicals during TexAQS 2006." Atmospheric Chemistry and Physics 11, no. 6 (March 16, 2011): 2471–85. http://dx.doi.org/10.5194/acp-11-2471-2011.
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Abstract. During the Texas Air Quality Study II (TexAQS 2006) campaign, a PEroxy Radical Chemical Amplifier (PERCA) was deployed on the NOAA research vessel R/V Brown to measure total peroxy radicals (HO2+Σ RO2). Day-time mixing ratios of HO2+Σ RO2 between 25 and 110 ppt were observed throughout the study area – the Houston/Galveston region and the Gulf coast of the US – and analyzed in relation to measurements of nitrogen oxides, volatile organic compounds (VOC) and photolysis rates to assess radical sources and sinks in the region. The measurements of HO2+Σ RO2 were used to calculate the in-situ net photochemical formation of ozone. Measured median values ranged from 0.6 ppb/h in clean oceanic air masses up to several tens of ppb/h in the most polluted industrial areas. The results are consistent with previous studies and generally agree with observations made during the previous TexAQS 2000 field campaign. The net photochemical ozone formation rates determined at Barbours Cut, a site immediately south of the Houston Ship Channel, were analyzed in relation to local wind direction and VOC reactivity to understand the relationship between ozone formation and local VOC emissions. The measurements of HO2+Σ RO2 made during the R/V Brown TexAQS 2006 cruise indicate that ozone formation is NOx-limited in the Houston/Galveston region and influenced by highly reactive hydrocarbons, especially alkenes from urban and industrial sources and their photo-oxidation products, such as formaldehyde.
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Terrill, Eric J., and Genevieve R. L. Taylor. "Entrainment of Air at the Transoms of Full-Scale Surface Ships." Journal of Ship Research 59, no. 01 (March 1, 2015): 49–65. http://dx.doi.org/10.5957/jsr.2015.59.1.49.
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We report on the results from a series of full-scale trials designed to quantify the air entrainment at the stern of an underway vessel. While an extremely complex region to model air entrainment due to the confluence of the breaking transom wave, bubbles from the bow, turbulence from the hull boundary layer, and bubbles and turbulence from propellers, the region is a desirable area to characterize and understand because it serves as the initial conditions of a ship's far-field bubbly wake. Experiments were conducted in 2003 from R/V Revelle and 2004 from R/VAthena II using a custombuilt conductivity probe vertical array that could be deployed at the blunt transom of a full-scale surface ship to measure the void fraction field. The system was designed to be rugged enough to withstand the full speed range of the vessels. From the raw timeseries data, the entrainment of air at speeds ranging from 2.1 to 7.2 m/s is computed at various depths and beam locations. The data represent the first such in-situ measurements from a full-scale vessel and can be used to validate two-phase ship hydrodynamic CFD codes and initialize far-field, bubbly wake CFD models.
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Gilman, J. B., J. F. Burkhart, B. M. Lerner, E. J. Williams, W. C. Kuster, P. D. Goldan, P. C. Murphy, et al. "Ozone variability and halogen oxidation within the Arctic and sub-Arctic springtime boundary layer." Atmospheric Chemistry and Physics Discussions 10, no. 6 (June 29, 2010): 15885–919. http://dx.doi.org/10.5194/acpd-10-15885-2010.
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Abstract. The influence of halogen oxidation on the variabilities of ozone (O3) and volatile organic compounds (VOCs) within the Arctic and sub-Arctic atmospheric boundary layer was investigated using field measurements from multiple campaigns conducted in March and April 2008 as part of the POLARCAT project. For the ship-based measurements, a high degree of correlation (r=0.98 for 544 data points collected north of 68° N) was observed between the acetylene to benzene ratio, used as a marker for halogen oxidation, and O3 signifying the vast influence of bromine oxidation throughout the ice-free regions of the North Atlantic. Concurrent airborne and ground-based measurements in the Alaskan Arctic substantiated this correlation and were used to demonstrate that halogen oxidation influenced O3 variability throughout the Arctic boundary layer during these springtime studies. Measurements aboard the R/V "Knorr" in the North Atlantic and Arctic Oceans provided a unique view of the transport of O3-poor air masses from the Arctic Basin to latitudes as far south as 52° N. FLEXPART, a Lagrangian transport model, was used to quantitatively determine the exposure of air masses encountered by the ship to first-year ice (FYI), multi-year ice (MYI), and total ICE (FYI+MYI). O3 anti-correlated with the modeled total ICE tracer (r=−0.86) indicating that up to 73% of the O3 variability measured in the Arctic marine boundary layer could be related to sea ice exposure.
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Gilman, J. B., J. F. Burkhart, B. M. Lerner, E. J. Williams, W. C. Kuster, P. D. Goldan, P. C. Murphy, et al. "Ozone variability and halogen oxidation within the Arctic and sub-Arctic springtime boundary layer." Atmospheric Chemistry and Physics 10, no. 21 (November 2, 2010): 10223–36. http://dx.doi.org/10.5194/acp-10-10223-2010.
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Abstract. The influence of halogen oxidation on the variabilities of ozone (O3) and volatile organic compounds (VOCs) within the Arctic and sub-Arctic atmospheric boundary layer was investigated using field measurements from multiple campaigns conducted in March and April 2008 as part of the POLARCAT project. For the ship-based measurements, a high degree of correlation (r = 0.98 for 544 data points collected north of 68° N) was observed between the acetylene to benzene ratio, used as a marker for chlorine and bromine oxidation, and O3 signifying the vast influence of halogen oxidation throughout the ice-free regions of the North Atlantic. Concurrent airborne and ground-based measurements in the Alaskan Arctic substantiated this correlation and were used to demonstrate that halogen oxidation influenced O3 variability throughout the Arctic boundary layer during these springtime studies. Measurements aboard the R/V Knorr in the North Atlantic and Arctic Oceans provided a unique view of the transport of O3-poor air masses from the Arctic Basin to latitudes as far south as 52° N. FLEXPART, a Lagrangian transport model, was used to quantitatively determine the exposure of air masses encountered by the ship to first-year ice (FYI), multi-year ice (MYI), and total ICE (FYI+MYI). O3 anti-correlated with the modeled total ICE tracer (r = −0.86) indicating that up to 73% of the O3 variability measured in the Arctic marine boundary layer could be related to sea ice exposure.
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Lund, Björn, Hans C. Graber, Katrin Hessner, and Neil J. Williams. "On Shipboard Marine X-Band Radar Near-Surface Current ‘‘Calibration’’." Journal of Atmospheric and Oceanic Technology 32, no. 10 (October 2015): 1928–44. http://dx.doi.org/10.1175/jtech-d-14-00175.1.
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AbstractThe ocean wave signatures within conventional noncoherent marine X-band radar (MR) image sequences can be used to derive near-surface current information. On ships, an accurate near-real-time record of the near-surface current could improve navigational safety. It could also advance understanding of air–sea interaction processes. The standard shipboard MR near-surface current estimates were found to have large errors (of the same order of magnitude as the signal) that are associated with ship speed and heading. For acoustic Doppler current profilers (ADCPs), ship heading errors are known to induce a spurious cross-track current that is proportional to the ship speed and the sine of the error angle. Conventional mechanical gyrocompasses are very reliable heading sensors, but they are too inaccurate for shipboard ADCPs. Within the ADCP community, it is common practice to correct the gyrocompass measurements with the help of multiantenna carrier-phase differential GPS systems. This study shows how a similar multiantenna GPS-based ship heading correction technique stands to improve the accuracy of MR near-surface current estimates. Changes to the standard MR near-surface current retrieval method that are necessary for high-quality results from ships are also introduced. MR and ADCP data collected from R/V Roger Revelle during the Impact of Typhoons on the Ocean in the Pacific (ITOP) program in 2010 are used to demonstrate the MR currents’ accuracy and reliability.
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Tucker, Sara C., Christoph J. Senff, Ann M. Weickmann, W. Alan Brewer, Robert M. Banta, Scott P. Sandberg, Daniel C. Law, and R. Michael Hardesty. "Doppler Lidar Estimation of Mixing Height Using Turbulence, Shear, and Aerosol Profiles." Journal of Atmospheric and Oceanic Technology 26, no. 4 (April 1, 2009): 673–88. http://dx.doi.org/10.1175/2008jtecha1157.1.
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Abstract The concept of boundary layer mixing height for meteorology and air quality applications using lidar data is reviewed, and new algorithms for estimation of mixing heights from various types of lower-tropospheric coherent Doppler lidar measurements are presented. Velocity variance profiles derived from Doppler lidar data demonstrate direct application to mixing height estimation, while other types of lidar profiles demonstrate relationships to the variance profiles and thus may also be used in the mixing height estimate. The algorithms are applied to ship-based, high-resolution Doppler lidar (HRDL) velocity and backscattered-signal measurements acquired on the R/V Ronald H. Brown during Texas Air Quality Study (TexAQS) 2006 to demonstrate the method and to produce mixing height estimates for that experiment. These combinations of Doppler lidar–derived velocity measurements have not previously been applied to analysis of boundary layer mixing height—over the water or elsewhere. A comparison of the results to those derived from ship-launched, balloon-radiosonde potential temperature and relative humidity profiles is presented.
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Pandolfi, Marco, Dennis Mooibroek, Philip Hopke, Dominik van Pinxteren, Xavier Querol, Hartmut Herrmann, Andrés Alastuey, et al. "Long-range and local air pollution: what can we learn from chemical speciation of particulate matter at paired sites?" Atmospheric Chemistry and Physics 20, no. 1 (January 13, 2020): 409–29. http://dx.doi.org/10.5194/acp-20-409-2020.
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Abstract. Here we report results of a detailed analysis of the urban and non-urban contributions to particulate matter (PM) concentrations and source contributions in five European cities, namely Schiedam (the Netherlands, NL), Lens (France, FR), Leipzig (Germany, DE), Zurich (Switzerland, CH) and Barcelona (Spain, ES). PM chemically speciated data from 12 European paired monitoring sites (one traffic, five urban, five regional and one continental background) were analysed by positive matrix factorisation (PMF) and Lenschow's approach to assign measured PM and source contributions to the different spatial levels. Five common sources were obtained at the 12 sites: sulfate-rich (SSA) and nitrate-rich (NSA) aerosols, road traffic (RT), mineral matter (MM), and aged sea salt (SS). These sources explained from 55 % to 88 % of PM mass at urban low-traffic-impact sites (UB) depending on the country. Three additional common sources were identified at a subset of sites/countries, namely biomass burning (BB) (FR, CH and DE), explaining an additional 9 %–13 % of PM mass, and residual oil combustion (V–Ni) and primary industrial (IND) (NL and ES), together explaining an additional 11 %–15 % of PM mass. In all countries, the majority of PM measured at UB sites was of a regional+continental (R+C) nature (64 %–74 %). The R+C PM increments due to anthropogenic emissions in DE, NL, CH, ES and FR represented around 66 %, 62 %, 52 %, 32 % and 23 %, respectively, of UB PM mass. Overall, the R+C PM increments due to natural and anthropogenic sources showed opposite seasonal profiles with the former increasing in summer and the latter increasing in winter, even if exceptions were observed. In ES, the anthropogenic R+C PM increment was higher in summer due to high contributions from regional SSA and V–Ni sources, both being mostly related to maritime shipping emissions at the Spanish sites. Conversely, in the other countries, higher anthropogenic R+C PM increments in winter were mostly due to high contributions from NSA and BB regional sources during the cold season. On annual average, the sources showing higher R+C increments were SSA (77 %–91 % of SSA source contribution at the urban level), NSA (51 %–94 %), MM (58 %–80 %), BB (42 %–78 %) and IND (91 % in NL). Other sources showing high R+C increments were photochemistry and coal combustion (97 %–99 %; identified only in DE). The highest regional SSA increment was observed in ES, especially in summer, and was related to ship emissions, enhanced photochemistry and peculiar meteorological patterns of the Western Mediterranean. The highest R+C and urban NSA increments were observed in NL and associated with high availability of precursors such as NOx and NH3. Conversely, on average, the sources showing higher local increments were RT (62 %–90 % at all sites) and V–Ni (65 %–80 % in ES and NL). The relationship between SSA and V–Ni indicated that the contribution of ship emissions to the local sulfate concentrations in NL has strongly decreased since 2007 thanks to the shift from high-sulfur- to low-sulfur-content fuel used by ships. An improvement of air quality in the five cities included here could be achieved by further reducing local (urban) emissions of PM, NOx and NH3 (from both traffic and non-traffic sources) but also SO2 and PM (from maritime ships and ports) and giving high relevance to non-urban contributions by further reducing emissions of SO2 (maritime shipping) and NH3 (agriculture) and those from industry, regional BB sources and coal combustion.
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Pinkel, Robert. "Velocity Imprecision in Finite-Beamwidth Shipboard Doppler Sonar: A First-Generation Correction Algorithm." Journal of Atmospheric and Oceanic Technology 29, no. 10 (October 1, 2012): 1569–80. http://dx.doi.org/10.1175/jtech-d-12-00041.1.
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Abstract The finite angular width of Doppler sonar beams introduces errors into the measurement of ocean velocity from moving ships. These errors are exacerbated as ship speed increases and as the acoustic scatter field becomes more inhomogeneous in space. Zooplanktonic scatters often reside in distinct quasi-isopycnal scattering layers. When measured from a moving ship, such layers appear to have a distinct velocity signature, even if the ocean is quiescent. Here, this effect is explored in a simple analytic model and a least squares algorithm is presented for remediating its signature. The algorithm corrects the measured velocity at any given depth, with the correction being a weighted sum of the depth gradient of log acoustic intensity at surrounding depths. The correction weights are a property of the specific sonar beam pattern. Once determined, they can be considered constant. The algorithm, when applied to a 50-kHz sonar on the Research Vessel (R/V) Roger Revelle, is found to remove roughly 90% of the error in vertical wavenumber spectra of shear. More sophisticated algorithms can be developed as experience with the present approach is gained.
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Prado, E., M. Gómez-Ballesteros, A. Cobo, F. Sánchez, A. Rodriguez-Basalo, B. Arrese, and L. Rodríguez-Cobo. "3D MODELING OF RIO MIERA WRECK SHIP MERGING OPTICAL AND MULTIBEAM HIGH RESOLUTION POINTS CLOUD." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W10 (April 17, 2019): 159–65. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w10-159-2019.
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<p><strong>Abstract.</strong> 3D reconstruction and virtual reality (VR) technology provide many opportunities for the documentation and dissemination of underwater cultural heritage. Advances in the development of underwater exploration technology have allowed for the first time to accurately reconstruct a complete 3D model of the cargo Río Miera in the Cantabrian Sea. Sunk on December 6, 1951 after a strong collision, the cargo ship Río Miera rests on a sandy bottom about 40 meters deep, very close to the Cantabrian coast. Located in an area of strong currents is a classic objective of the region for the most experienced divers. The survey was carried out this summer in R/V Ramón Margalef of the IEO, acquiring acoustic data with multibeam echo sounders and hundreds of images acquired by a remotely piloted underwater vehicle. The campaign is part of the PhotoMARE project - Underwater Photogrammetry for MArine Renewable Energy. This work describes the workflow regarding the survey, images and acoustic data acquisition, data processing, optic 3D point cloud color enhancement and acoustic and optic dataset merging procedure to obtain a complete 3D model of wreck Río Miera in Cantabrian Sea. Through this project, Spanish Institute of Oceanography – IEO have advanced – combining acoustic and image methods - in the generation of 3D models of archaeological sites and submerged structures.</p>
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Krüger, K., and B. Quack. "Introduction to special issue: the <i>TransBrom Sonne</i> expedition in the tropical West Pacific." Atmospheric Chemistry and Physics 13, no. 18 (September 25, 2013): 9439–46. http://dx.doi.org/10.5194/acp-13-9439-2013.
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Abstract. This special section of Atmospheric Chemistry and Physics gives an overview of scientific results, collected during a West Pacific ship expedition in October 2009 with the Research Vessel (R/V) Sonne. The cruise focussed on chemical interactions between the ocean surface and the atmosphere above the tropical West Pacific and was planned within the national research project TransBrom (www.geomar.de/~transbrom). TransBrom aimed to particularly investigate very short lived bromine compounds in the ocean and their transport to and relevance for the stratosphere. For this purpose, chemical and biological parameters were analysed in the ocean and in the atmosphere, accompanied by a high frequency of meteorological measurements, to derive new insights into the multidisciplinary research field. This introduction paper presents the scientific goals and the meteorological and oceanographic background. The main research findings of the TransBrom Sonne expedition are highlighted.
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Buffaloe, G. M., D. A. Lack, E. J. Williams, D. Coffman, K. L. Hayden, B. M. Lerner, S.-M. Li, et al. "Black carbon emissions from in-use ships: a California regional assessment." Atmospheric Chemistry and Physics Discussions 13, no. 9 (September 23, 2013): 24675–712. http://dx.doi.org/10.5194/acpd-13-24675-2013.
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Abstract. Black carbon (BC) mass emission factors (EFBC; g-BC (kg-fuel)−1) from a variety of ocean going vessels have been determined from measurements of BC and carbon dioxide (CO2) concentrations in ship plumes intercepted by the R/V Atlantis during the 2010 California Nexus (CalNex) campaign. The ships encountered were all operating within 24 nautical miles of the California coast and were utilizing relatively low sulphur fuels. Black carbon concentrations within the plumes, from which EFBC values are determined, were measured using four independent instruments: a photoacoustic spectrometer and a particle soot absorption photometer, which measure light absorption, and a single particle soot photometer and soot particle aerosol mass spectrometer, which measure the mass concentration of refractory BC directly. The measured EFBC have been divided into vessel type categories and engine type categories, from which averages have been determined. The geometric average EFBC, determined from over 71 vessels and 135 plumes encountered, was 0.31 g-BC (kg-fuel)−1. The most frequent engine type encountered was the slow speed diesel (SSD), and the most frequent SSD vessel type was the cargo ship sub-category. Average and median EFBC values from the SSD category are compared with previous observations from the Texas Air Quality Study (TexAQS) in 2006, during which the ships encountered were predominately operating on high sulphur fuels. There is a statistically significant difference between the EFBC values from CalNex and TexAQS for SSD vessels and for the cargo and tanker ship types within this engine category. The CalNex EFBC values are lower than those from TexAQS, suggesting that operation on lower sulphur fuels is associated with smaller EFBC values.
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Jessup, A. T., and R. Branch. "Integrated Ocean Skin and Bulk Temperature Measurements Using the Calibrated Infrared In Situ Measurement System (CIRIMS) and Through-Hull Ports." Journal of Atmospheric and Oceanic Technology 25, no. 4 (April 1, 2008): 579–97. http://dx.doi.org/10.1175/2007jtecho479.1.
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Abstract The design and performance of a shipboard-integrated system for underway skin and bulk temperature is presented. The system consists of the Calibrated Infrared In situ Measurement System (CIRIMS) and through-hull temperature sensors. The CIRIMS is an autonomous shipboard radiometer system that measures the sea surface skin temperature Tskin for validation of satellite-derived sea surface temperature products. General design considerations for shipboard radiometer systems are discussed and the philosophy behind the CIRIMS design is presented. Unique features of the design include a constant temperature housing to stabilize instrument drift, a two-point dynamic calibration procedure, separate sky- and sea-viewing radiometers for simultaneous measurements, and the ability to use an infrared transparent window for environmental protection. Laboratory testing and field deployments are used to establish an estimated error budget, which includes instrumentation and environmental uncertainties. The combination of this testing and field comparison to the Marine-Atmosphere Emitted Radiance Interferometer (M-AERI) and Infrared SST Autonomous Radiometer (ISAR) instruments indicates that the CIRIMS meets the design goal of ±0.10°C accuracy. Temperature and pressure sensors were installed in custom-designed through-hull ports on the NOAA research vessel (R/V) Ronald H. Brown and the University of Washington R/V Thomas G. Thompson to complement the CIRIMS measurements. The ports allow sensors to be installed while the ship is in water and can accommodate a variety of sensors. The combined system provides the ability to measure near-surface temperature profiles from the skin to a depth of 5 m while underway.
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Messager, C., S. Speich, and E. Key. "Observed response of the marine atmospheric boundary layer to the Southern Ocean fronts during the IPY BGH 2008 cruise." Ocean Science Discussions 9, no. 2 (March 28, 2012): 1387–436. http://dx.doi.org/10.5194/osd-9-1387-2012.
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Abstract. A set of meteorological instruments was added to an oceanographic cruise crossing the Southern Ocean from Cape Town to 57°33' S on board the R/V Marion Dufresne during the summer 2008. The Cape Cauldron, the subtropical, subantarctic, polar and southern Antarctic circumpolar current fronts were successively crossed. The recorded data permitted to derive the exchange of momentum, heat and water vapour at the ocean-atmosphere interface. A set of 38 radiosonde releases complemented the dataset. The marine atmospheric boundary layer characteristics and air-sea interaction when ship crossed the fronts and eddies are discussed. The specific role of the atmospheric synoptic systems advection on the air-sea interaction is highlighted over these regions. The dynamic associated with these systems drive the vertical mixing of the MABL by wind shear effect and/or the vertical thermal mixing. The MABL is stabilized (destabilized) and mixing is inhibited (enhanced) over the warm front sides if meridional wind component is northerly (southerly).
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Fischer, H., A. Pozzer, T. Schmitt, P. Jöckel, T. Klippel, D. Taraborrelli, and J. Lelieveld. "Hydrogen peroxide in the marine boundary layer over the southern Atlantic during the OOMPH cruise in March 2007." Atmospheric Chemistry and Physics Discussions 14, no. 22 (December 2, 2014): 30547–73. http://dx.doi.org/10.5194/acpd-14-30547-2014.
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Abstract. In the OOMPH (Ocean Organics Modifying Particles in both Hemispheres) project a ship measurement cruise took place in the late austral summer from 1 to 23 March 2007. The French R/V Marion Dufresne sailed from Punta Arenas, Chile (70.85° W, 53.12° S) to La Reunion island (55.36° E, 21.06° S) across the southern Atlantic Ocean. In-situ measurements of hydrogen peroxide, methylhydroperoxide and ozone were performed and are compared to simulations with the atmospheric chemistry global circulation model EMAC. The model generally reproduces the measured trace gas levels, but underestimates hydrogen peroxide mixing ratios at high wind speeds, indicating too strong dry deposition to the ocean surface. An interesting feature during the cruise is a strong increase of hydrogen peroxide, methylhydroperoxide and ozone shortly after midnight off the west coast of Africa due to an increase in the boundary layer height, leading to downward transport from the free troposphere, which is realistically reproduced by the model.
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Watling, Dick. "Notes on the status of Kuhl's Lorikeet Vini kuhlii in the Northern Line Islands, Kiribati." Bird Conservation International 5, no. 4 (December 1995): 481–89. http://dx.doi.org/10.1017/s0959270900001192.
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SummaryKuhl's Lorikeet Vini kuhlii has a precarious status reflected by its disjunct distribution in the Pacific, with surviving populations in the Northern Line (Kiribati) and Austral Islands (French Polynesia) some 3,000 km apart, possibly as a result of Polynesian trade in red feathers. The species is extinct in the southern Cook Islands. On Rimatara (Austral Islands), where it is believed indigenous, it is still common but the recent introduction of the Rattus norvegicus is of concern. In the Northern Line Islands, R. rattus appears to have all but extirpated the lorikeet on Tabuaeran (Fanning Island), but one small population has apparently survived for over 70 years, an explanation for which may guide in situ conservation of Vini lorikeets on ship-rat-infested islands elsewhere. The arid and unpredictable climate of Kiritimati (Christmas Island) may preclude the establishment of lorikeets. Only on Teraina (Washington Island), where over 1,000 V. kuhlii survive, are there no confirmed threats and good in situ conservation potential.
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Genrich, J. F., and J. B. Minster. "Near‐real time reduction of shipboard gravity using Kalman‐filtered GPS measurements." GEOPHYSICS 56, no. 12 (December 1991): 1971–79. http://dx.doi.org/10.1190/1.1443008.
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We have developed a Kalman filter to estimate accurate Eötvös corrections and horizontal ship accelerations from Global Positioning System (GPS) fixes. High‐resolution shipboard gravity measurements are obtained with a newly designed, linear phase, Finite Impulse Response (FIR) low‐pass filter. Both filters are combined to yield accurate, near‐real time, Eötvös‐corrected underway gravity estimates. Error ranges that reflect uncertainty in navigation for these estimates are calculated from autocovariances of Kalman velocity estimates by means of variance propagation expressions for time‐invariant linear digital filters. Estimates of horizontal ship acceleration are combined with a simplified instrument impulse response model in an attempt to remove transient noise from the gravimeter output. We apply the technique to data collected by two shipboard gravimeters, a LaCoste & Romberg Model S Air‐Sea Gravity Meter and a Bell Aerospace BGM-3 Marine Gravity Meter System, operated side‐by‐side on the Scripps R/V Thomas Washington during Leg 1 of the Roundabout expedition. In the absence of significant horizontal accelerations due to course or speed changes, both instruments yield data with good repeatability, characterized by rms differences of less than 1 mGal. Horizontal accelerations generate transient signals that cannot be modeled at present to an accuracy of better than 5 mGal. Difficulties in removing these transients are primarily due to insufficient quantitative knowledge of the response of the instrument, including the gyro‐stabilized platform. This can be determined analytically or empirically.
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Buffaloe, G. M., D. A. Lack, E. J. Williams, D. Coffman, K. L. Hayden, B. M. Lerner, S. M. Li, et al. "Black carbon emissions from in-use ships: a California regional assessment." Atmospheric Chemistry and Physics 14, no. 4 (February 18, 2014): 1881–96. http://dx.doi.org/10.5194/acp-14-1881-2014.
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Abstract. Black carbon (BC) mass emission factors (EFBC; g BC (kg fuel)−1) from a variety of ocean-going vessels have been determined from measurements of BC and carbon dioxide (CO2) concentrations in ship plumes intercepted by the R/V Atlantis during the 2010 California Nexus (CalNex) campaign. The ships encountered were all operating within 24 nautical miles of the California coast and were utilizing relatively low sulphur fuels (average fuel sulphur content of 0.4%, 0.09% and 0.03% for vessels operating slow-speed, medium-speed and high-speed diesel engines, respectively). Black carbon concentrations within the plumes, from which EFBC values are determined, were measured using four independent instruments: a photoacoustic spectrometer and a particle soot absorption photometer, which measure light absorption, and a single particle soot photometer and soot particle aerosol mass spectrometer, which measure the mass concentration of refractory BC directly. These measurements have been used to assess the level of agreement between these different techniques for the determination of BC emission factors from ship plumes. Also, these measurements greatly expand upon the number of individual ships for which BC emission factors have been determined during real-world operation. The measured EFBC's have been divided into vessel type categories and engine type categories, from which averages have been determined. The geometric average EFBC (excluding outliers) determined from over 71 vessels and 135 plumes encountered was 0.31 &pm; 0.31 g BC (kg fuel)−1, where the standard deviation represents the variability between individual vessels. The most frequent engine type encountered was the slow-speed diesel (SSD), and the most frequent SSD vessel type was the cargo ship sub-category. Average and median EFBC values from the SSD category are compared with previous observations from the Texas Air Quality Study (TexAQS) in 2006, during which the ships encountered were predominately operating on high-sulphur fuels (average fuel sulphur content of 1.6%). There is a statistically significant difference between the EFBC values from CalNex and TexAQS for SSD vessels and for the cargo and tanker ship types within this engine category. The CalNex EFBC values are lower than those from TexAQS, suggesting that operation on lower sulphur fuels is associated with smaller EFBC values.
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Maksimova, P. V., A. V. Chernov, V. A. Likhomanov, N. A. Krupina, and V. A. Likhomanov. "Research of R/V “Akademik Tryoshnikov” hull structures response to ice actions during the first stage of the expedition “Transarktika-2019”." Arctic and Antarctic Research 66, no. 1 (March 27, 2020): 82–101. http://dx.doi.org/10.30758/0555-2648-2020-66-1-82-101.
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At present, oil-producing offshore structures, as well as transport vessels transporting oil products extracted in the seas of the Russian Arctic are equipped with ice load monitoring systems (ILMS) to prevent environmental disasters. The ice-resistant self-propelled platform (IRSPP) that is under construction now, according to the design should be equipped with this system. First of all this system is the main system for ensuring the platform’s safety in ice conditions, and secondly makes the platform’s hull a unique tool for solving a wide range of tasks to study the effects of ice on any construction.The main goal of the research during the expedition “Transarktika-2019” was to obtain the necessary data for the development of an ice load monitoring system of the constructing IRSPP “North Pole” and testing the prototype of the ILMS at long vessel’s drift in ice.The measurements of stresses in the hull structures of the R/V “Akademik Tryoshnikov” were carried out during impacts on ice ridges and during ice compressions.The standard ship ice load monitoring system (SILMS) of the R/V “Akademik Tryoshnikov” and strain gauges additionally installed on the frames and a shell plating in the middle part of the hull were used to perform the measurements.The analysis of the obtained data showed that the maximal loads on the hull occurred during the forcing of ice ridges but the level of maximum stresses was not a danger to the hull.Compressions during the drift did not have a strong effect on the ship’s hull. The data obtained made it possible to identify a number of features for the operation of ILMS in similar conditions.Based on the results of the expedition research, recommendations for the design of the architecture of the ILMS for IRSPP were issued. The results of further analysis of the obtained materials will be used in the development of data processing algorithms for ILMS for IRSPP, as well as for the development of the prospective programs of scientific research of deformation, fracture and other processes of various scales that occur in drifting ice during the future drifts of the IRSPP “North Pole”.The authors have no competing interests.
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Fatmawaty, Riryn, and Putri Ayu Anggraini. "AN ANALYSIS OF ENGLISH WORD FORMATION PROCESSES IN BEATS APART NOVEL BY ALANDA KARIZA AND KEVIN ADITYA." Jurnal ELink 6, no. 1 (July 1, 2019): 164. http://dx.doi.org/10.30736/e-link.v6i1.125.
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This research discusses word formation process used in Beats Aparts novel By Alanda Kariza And Kevin Aditya. The aims to describe how are English word created and found out types of word formation processes. To analyze the data found the researchers applied English word formation in English morphology.This is qualitative descriptive research. The data were taken from Beats A parts novel By Alanda Kariza And Kevin Aditya. The main theory which was used in this research is taken from the book under the titleThe Study of Language,Third Edition byYule (2006). The result of this research showed that the process of borrowing from other language, there were Spain, China, French, Italy and Germany. The process of compounding, found out some category, there wereAdv + N, Adv + Adv, Adv + Adj, Adv + V, Adj + N, Adj + Adv, Adj + V, V + N, V + Adj, N + N, N + Adv, N + Adj, N + V. The process of clipping found out two category, there are foreclipped and backclipped. The process of conversion only found word from noun became adverb. The process of derivation consist from adding prefix such us un-, re-, dis-, im-. Adding suffix such us –ly, -ish, -er, -ness, -ion / tion, -able, -ful, -ship, -ment, -ate, -r, -en, -ity, -tic, -ism, -al, -ar. Adding infix such us –s-, -ly-, -bor-. The process of multiple processes is all words including multiple processes in this research have a word that covers the processes of back formation and derivation. This research found out types of English word formation processes such as borrowing, compounding, blending, clipping, back formation, conversion, acronyms,derivation and multiple processes. The researcher hopes that this research can improve the knowledge about morphology, especially in word formation. Key words: Morphology, Word formation, Novel
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Guigand, Cedric M., Robert K. Cowen, Joel K. Llopiz, and David E. Richardson. "A Coupled Asymmetrical Multiple Opening Closing Net with Environmental Sampling System." Marine Technology Society Journal 39, no. 2 (June 1, 2005): 22–24. http://dx.doi.org/10.4031/002533205787444042.
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Recruitment levels of fishes are potentially related to the abundance of larval fishes and their food source. A system that could allow for the concurrent investigation of fine-scale distribution of fish larvae and their potential prey could add significantly to the understanding of the early life history of marine fishes. A coupled Multiple Opening Closing Net and Environmental Sensing System (MOCNESS) that combines two sub-systems (1 m2 and 4 m2 net sets) working in synchronization was designed to answer these questions. The mesh size was different on each set of nets allowing the collection of a broad size range of organisms while optimizing the catch of larger fish larvae and eliminating unnecessary large samples of zooplankton. Moreover, the system eliminated the need to deploy separate MOCNESS using different mesh sizes, thus reducing ship time costs, and avoiding any aliasing associated with trying to sample the same water mass with separate nets fished sequentially. The system has been used at sea under varying weather conditions onboard the R/V F. G. Walton Smith and sampled adequately.
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Rutledge, Steven A., V. Chandrasekar, Brody Fuchs, Jim George, Francesc Junyent, Brenda Dolan, Patrick C. Kennedy, and Kyla Drushka. "SEA-POL Goes to Sea." Bulletin of the American Meteorological Society 100, no. 11 (November 2019): 2285–301. http://dx.doi.org/10.1175/bams-d-18-0233.1.
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AbstractA new, advanced radar has been developed at Colorado State University (CSU). The Sea-Going Polarimetric (SEA-POL) radar is a C-band, polarimetric Doppler radar specifically designed to deploy on research ships. SEA-POL is the first such weather radar developed in the United States. Ship-based weather radars have a long history, dating back to GATE in 1974. The GATE radars measured only reflectivity. After GATE, ship radars also provided Doppler measurements. SEA-POL represents the next advancement by adding dual-polarization technology, the ability to transmit and receive both horizontal and vertical polarizations. This configuration provides information about hydrometeor size, shape, and phase. As a result, superior rain-rate estimates are afforded by the dual-polarization technology, along with hydrometeor identification and overall improved data quality. SEA-POL made its first deployment as part of the Salinity Processes in the Upper Ocean Regional Study, second field phase (SPURS-2) fall 2017 cruise to the eastern tropical Pacific, sailing on the R/V Roger Revelle. SPURS-2 was a field project to investigate the fate of freshwater deposited on the ocean’s surface. Oceanographers are keenly interested in how fast these freshwater patches mix out by wind and upper-ocean turbulence, as the less dense rainfall sitting atop the salty ocean inhibits mixing through increased stability. To this end, during SPURS-2, SEA-POL produced rain maps identifying the location of freshwater lenses on the ocean’s surface thereby providing context for measurements of SST and salinity. Examples of SEA-POL polarization measurements are also discussed to assess microphysical processes within oceanic convection. Future ocean-based field campaigns will now benefit from SEA-POL’s advanced dual-polarization technology.
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Bhushan, Shanti, Tao Xing, Pablo Carrica, and Frederick Stern. "Model-and Full-Scale URANS Simulations of Athena Resistance, Powering, Seakeeping, and 5415 Maneuvering." Journal of Ship Research 53, no. 04 (December 1, 2009): 179–98. http://dx.doi.org/10.5957/jsr.2009.53.4.179.
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This study demonstrates the versatility of a two-point, multilayer wall function in computing model-and full-scale ship flows with wall roughness and pressure gradient effects. The wall-function model is validated for smooth flat-plate flows at Reynolds numbers up to 109, and it is applied to the Athena R/V for resistance, propulsion, and seakeeping calculations and to fully appended DTMB 5415 for a maneuvering simulation. Resistance predictions for Athena bare hull with skeg at the model scale compare well with the near-wall turbulence model results and experimental fluid dynamics (EFD) data. For full-scale simulations, frictional resistance coefficient predictions using smooth wall are in good agreement with the International Towing Tank Conference (ITTC) line. Rough-wall simulations show higher frictional and total resistance coefficients, where the former is found to be in good agreement with the ITTC correlation allowance. Self-propelled simulations for the fully appended Athena performed at full scale using rough-wall conditions compare well with full-scale data extrapolated from model-scale measurements using the ITTC ship-model correlation line including a correlation allowance. Full-scale computations are performed for the towed fully appended Athena free to sink and trim and the boundary layer and wake profiles are compared with full-scale EFD data. Rough-wall results are found to be in better agree-ment with the EFD data than the smooth-wall results. Seakeeping calculations are performed for the demonstration purpose at both model-and full-scale. Maneuvering calculation shows slightly more efficient rudder action, lower heading angle overshoots, and lower roll damping for full-scale than shown by the model scale.
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Hedgecock, I. M., C. N. Gencarelli, G. J. Sch{ü}rmann, F. Sprovieri, and N. Pirrone. "Measurements and modelling of ozone in the Mediterranean MBL: an investigation of the importance of ship emissions to local ozone production." Atmospheric Chemistry and Physics Discussions 12, no. 7 (July 5, 2012): 16557–602. http://dx.doi.org/10.5194/acpd-12-16557-2012.
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Abstract. Elevated concentrations of ground level ozone are both hazardous to human health and detrimental to agricultural production. The Mediterranean Basin, due to its position under the descending branch of the Hadley Cell circulation during the summer months, enjoys periods of stable, sunny and warm weather which provide ideal conditions for the production of ozone. The presence of major population centres and numerous industrialised areas in the coastal zone result in both a continual supply of ozone precursor compounds and also a significant number of people to suffer the consequences of high ozone concentrations. Using the WRF/Chem model validated with data obtained from seven oceanographic measurement campaigns, performed between 2000 and 2010, aboard the Italian Research Council's R. V. Urania, and also from a number of EMEP monitoring stations located around the Mediterranean Basin, the importance of emissions from maritime traffic in the region has been investigated. The model results indicate that over large areas of the Mediterranean emissions from shipping contribute between 5 and 10 ppb to the ground level O3 daily average concentration during the summer. The contribution to the hourly average O3 is up to 40 ppb in some particularly busy shipping lanes. Importantly the results suggest that in a number of coastal areas the contribution from ship emissions to the local O3 concentration can make the difference between complying with the EU Air Quality standard of a maximum 8 h mean of 120 μg m−3 and exceeding it.
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van Hilten, Max J., and Paul H. M. Wolkenfelt. "The Rate of Turn Required for Geographically Fixed Turns: A Formula and Fast-Time Simulations." Journal of Navigation 53, no. 1 (January 2000): 146–55. http://dx.doi.org/10.1017/s0373463399008590.
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This paper concerns the derivation of a formula to follow geographically fixed turns in a homogeneous current or tidal stream. Until now, various well-founded but limited approximations have been used. In principle, all these approximations are based on the formula v = ω × R. One result of this research is the development and use of a fast-time simulation program. The initial aim was to illustrate to trainees the consequences and, in particular, the possible dangers of these approximations. The fast-time simulation program can be used in support of real-time simulation. Comparisons with real-time simulations carried out by the Dutch Pilots' Corporation (STODEL) indicate that the fast-time simulations generate turning-circle diameters that differ by a maximum 4 percent. The relationship with path-prediction is also dealt with. The possibility of applying the developed formulae in practice and for passage planning is currently under investigation. The fast-time simulation program has not been developed for one specific ship: apart from the use of an assumed position of the pivoting point at 1/3 of the ship's length from the bow, it does not take hydrodynamic effects into account.
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Xie, H., R. Lei, C. Ke, H. Wang, Z. Li, J. Zhao, and S. F. Ackley. "Summer sea ice characteristics and morphology in the Pacific Arctic sector as observed during the CHINARE 2010 cruise." Cryosphere 7, no. 4 (July 9, 2013): 1057–72. http://dx.doi.org/10.5194/tc-7-1057-2013.
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Abstract. In the summer of 2010, atmosphere–ice–ocean interaction was studied aboard the icebreaker R/V Xuelong during the Chinese National Arctic Research Expedition (CHINARE), in the sea ice zone of the Pacific Arctic sector between 150° W and 180° W up to 88.5° N. The expedition lasted from 21 July to 28 August and comprised of ice observations and measurements along the cruise track, 8 short-term stations and one 12-day drift station. Ship-based observations of ice thickness and concentration are compared with ice thickness measured by an electromagnetic induction device (EM31) mounted off the ship's side and ice concentrations obtained from AMSR-E. It is found that the modal thickness from ship-based visual observations matches well with the modal thickness from the mounted EM31. A grid of 8 profiles of ice thickness measurements (four repeats) was conducted at the 12-day drift station in the central Arctic (~ 86°50´ N–87°20´ N) and an average melt rate of 2 cm day−1, primarily bottom melt, was found. As compared with the 2005 data from the Healy/Oden Trans-Arctic Expedition (HOTRAX) for the same sector but ~ 20 days later (9 August to 10 September), the summer 2010 was first-year ice dominant (vs. the multi-year ice dominant in 2005), 70% or less in mean ice concentration (vs. 90% in 2005), and 94–114 cm in mean ice thickness (vs. 150 cm in 2005). Those changes suggest the continuation of ice thinning, less concentration, and younger ice for the summer sea ice in the sector since 2007 when a record minimum sea ice extent was observed. Overall, the measurements provide a valuable dataset of sea ice morphological properties over the Arctic Pacific Sector in summer 2010 and can be used as a benchmark for measurements of future changes.
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Berkson, Jonathan M., and George W. DuPree. "United States Arctic Research Vessels." Marine Technology Society Journal 35, no. 3 (September 1, 2001): 31–37. http://dx.doi.org/10.4031/002533201788057882.
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Recent concerns with pollution and climate change in the Arctic have led to new monitoring and research programs that require the support of arctic research vessels. This paper reviews the status of U.S. surface and submersible research platforms with a focus on surface ships. During the Science Ice Expedition (SCICEX) program in the 1990s, U.S. Navy submarines were successfully used as research vessels and extensive oceanographic data were collected during under-ice transits. With the decommissioning of the Sturgeon-class submarines, future under-ice research cruises are uncertain and will depend on the availability of other ice-capable submarines or the development of high-endurance automous underwater vehicles. For scientific work on surface research vessels the U.S. has two multi-mission polar icebreakers and a new icebreaking research vessel. In addition, University of Alaska has begun concept designs for replacing the R/V Alpha Helix with an intermediatesized, ice-strengthened ship for oceanographic and fisheries research around the coast of Alaska. Two multi-mission Polar-class Coast Guard cutters, USCGC Polar Star and USCGC Polar Sea, are equipped to serve as oceanographic research vessels and have made important contributions to both Arctic and Antarctic science programs during the last twenty-five years. USCGC Healy, which was designed from the keel up as a research vessel and heavy icebreaker, is capable of supporting large multi-disciplinary studies. The ship, which will be operated as a dedicated Arctic research vessel, was delivered in November 1999, completed ice and science trials in July 2000, and conducted its first dedicated science cruise in the Eastern Arctic in the summer of 2001. The advent of Healy adds significantly to the U.S. science-support capability in the Arctic.
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Ganeshan, Manisha, and Dong L. Wu. "The open-ocean sensible heat flux and its significance for Arctic boundary layer mixing during early fall." Atmospheric Chemistry and Physics 16, no. 20 (October 27, 2016): 13173–84. http://dx.doi.org/10.5194/acp-16-13173-2016.
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Abstract. The increasing ice-free area during late summer has transformed the Arctic to a climate system with more dynamic boundary layer (BL) clouds and seasonal sea ice growth. The open-ocean sensible heat flux, a crucial mechanism of excessive ocean heat loss to the atmosphere during the fall freeze season, is speculated to play an important role in the recently observed cloud cover increase and BL instability. However, lack of observations and understanding of the resilience of the proposed mechanisms, especially in relation to meteorological and interannual variability, has left a poorly constrained BL parameterization scheme in Arctic climate models. In this study, we use multi-year Japanese cruise-ship observations from R/V Mirai over the open Arctic Ocean to characterize the surface sensible heat flux (SSHF) during early fall and investigate its contribution to BL turbulence. It is found that mixing by SSHF is favored during episodes of high surface wind speed and is also influenced by the prevailing cloud regime. The deepest BLs and maximum ocean–atmosphere temperature difference are observed during cold air advection (associated with the stratocumulus regime), yet, contrary to previous speculation, the efficiency of sensible heat exchange is low. On the other hand, the SSHF contributes significantly to BL mixing during the uplift (low pressure) followed by the highly stable (stratus) regime. Overall, it can explain ∼ 10 % of the open-ocean BL height variability, whereas cloud-driven (moisture and radiative) mechanisms appear to be the other dominant source of convective turbulence. Nevertheless, there is strong interannual variability in the relationship between the SSHF and the BL height which can be intensified by the changing occurrence of Arctic climate patterns, such as positive surface wind speed anomalies and more frequent conditions of uplift. This study highlights the need for comprehensive BL observations like the R/V Mirai for better understanding and predicting the dynamic nature of the Arctic climate.
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Jakobsen, Flemming, and Stéphane Castejon. "Calculation of the Discharge through Øresund at the Drogden Sill by Measurements at two Fixed Stations." Hydrology Research 26, no. 3 (June 1, 1995): 237–58. http://dx.doi.org/10.2166/nh.1995.0014.
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The paper aims at relating the discharge through Øresund (the sound between Denmark and Sweden) to measured current and stratification at the two fixed stations Nordre Røse (St. 24) and Flinten SW (St. 21). The information on the discharge is gained from ship-based ADCP measurements carried out on board R/V Sensor. Close to the sill area, Saltholm island divides the flux into two parts: One part through the Drogden Channel (where St. 24 is located), and the other through the Flinten Channel (where St. 21 is located). The establishment of a relationship between discharge and current measurements at two fixed stations is based on three basic assumptions: 1) the stratification in the Drogden and Flinten channels is considered to be one- or two-layered; 2) the flow to be driven by a constant energy gradient across each channel; and 3) by simplifying the bathymetry of the cross-sections. The study of the water discharge through Øresund reveals a close relationship of hydrographic measurements (current profile, salinity profile and water level) at Nordre Røse (St. 24) and Flinten SW (St. 21). From the investigation an interface friction factor (fi/2) for the Drogden Channel is found to be 5.6 × 10−3. This value is applied for the Flinten channel analysis as well.
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Barton, Ian J. "Comparison of In Situ and Satellite-Derived Sea Surface Temperatures in the Gulf of Carpentaria." Journal of Atmospheric and Oceanic Technology 24, no. 10 (October 1, 2007): 1773–84. http://dx.doi.org/10.1175/jtech2084.1.
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Abstract During 30 days in May and June 2003, the R/V Southern Surveyor was operating in the Gulf of Carpentaria, northern Australia. Measurements of sea surface temperature (SST) were made with an accurate single-channel infrared radiometer as well as with the ship’s thermosalinograph. These ship-based measurements have been used to assess the quality of the SST derived from nine satellite-borne instruments. The satellite dataset compiled during this period also allows the intercomparison of satellite-derived SST fields in areas not covered by the ship’s track. An assessment of the SST quality from each satellite instrument is presented, and suggestions for blending ground and satellite measurements into a single product are made. These suggestions are directly applicable to the international Global Ocean Data Assimilation Experiment (GODAE) High Resolution SST Pilot Project (GHRSST-PP) that is currently developing an operational system to provide 6-hourly global fields of SST at a spatial resolution close to 10 km. The paper demonstrates how the Diagnostic Datasets (DDSs) and Matchup Database (MDB) of the GHRSST-PP can be used to monitor the quality of individual and blended SST datasets. Recommendations for future satellite missions that are critical to the long-term generation of accurate blended SST datasets are included.
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Glukhovets, D. I. "STUDY OF BIO-OPTICAL CHARACTERISTICS OF THE BARENTS AND NORWEGIAN SEAS SURFACE LAYER WATERS IN SUMMER 2017." XXII workshop of the Council of nonlinear dynamics of the Russian Academy of Sciences 47, no. 1 (April 30, 2019): 145–60. http://dx.doi.org/10.29006/1564-2291.jor-2019.47(1).44.
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A study of the surface layer bio-optical properties of the Barents and Norwegian Seas in the summer of 2017 is carried out. Ship data were obtained during the 68th cruise of the R/V ‘Akademik Mstislav Keldysh’ (June-August 2017). Using a flow-through system, the fluorescence intensities of chlorophyll ‘a’ and dissolved organic matter as well as the salinity and temperature of the water surface layer along the ship’s route were continuously recorded. Seawater samples were taken for spectral fluorescence and absorbance measurements performed with a laser spectrometer and an integrating cavity absorption meter. The results are compared with the data of direct determinations of the chlorophyll concentration. Frequent continuous cloudiness prevented the use of ocean color data for the Norwegian Sea. In the coccolithophore bloom area in the Barents Sea, the results of shipboard measurements are compared with the data of OLCI satellite scanner. In this area, standard OLCI algorithms overestimate chlorophyll concentration, while the regression algorithm works better than based on neural networks. Comparison of the fluorescence and absorption spectra has shown the possibility of carrying out a rapid assessment of the chlorophyll concentration using optical methods. The change in the coefficients of the regression equations of chlorophyll fluorescence intensity and its concentration, determined by direct methods for different regions, is shown.
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Villablanca, Roberto, Guillermo Luna-Jorquera, Victor H. Marín, Stefan Garthe, and Alejandro Simeone. "How does a generalist seabird species use its marine habitat? The case of the kelp gull in a coastal upwelling area of the Humboldt Current." ICES Journal of Marine Science 64, no. 7 (August 17, 2007): 1348–55. http://dx.doi.org/10.1093/icesjms/fsm120.
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AbstractVillablanca, R., Luna-Jorquera, G., Marín, V. H., Garthe, S., and Simeone, A. 2007. How does a generalist seabird species use its marine habitat? The case of the kelp gull in a coastal upwelling area of the Humboldt Current. – ICES Journal of Marine Science, 64: 1348–1355. The distribution of kelp gulls (Larus dominicanus) was studied by ship-based transect counts in the SE Pacific Ocean off Chile, South America. Some 96–98% of the kelp gulls were in a band less than 20 km from the coast, mainly near the breeding colony on Pájaros Island and the City of Coquimbo. Abundance did not change significantly among years, but was influenced significantly by distance to land. Principal component analysis yielded two components that jointly explain 53% of the standardized variance. The first (explaining 36% of the variance) includes distance to the nearest coast and water depth, the second (17%) associates with the presence of fishing vessels. The results suggest that the stability of the summer distribution of kelp gulls is generated by the large and semi-permanent offer of food at fish markets and city sewage works, as well as the location of the breeding colonies. Further analysis on other temporal scales (seasonal, decadal) associated with reproductive or non-reproductive changes within the population and/or ENSO cycles will be necessary to confirm the multiscale stability of the pattern described.
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Henry, Charlie, and Paulene O. Roberts. "BACKGROUND FLUORESCENCE VALUES AND MATRIX EFFECTS OBSERVED USING SMART PROTOCOLS IN THE ATLANTIC OCEAN AND GULF OF MEXICO." International Oil Spill Conference Proceedings 2001, no. 2 (March 1, 2001): 1203–7. http://dx.doi.org/10.7901/2169-3358-2001-2-1203.
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ABSTRACT For a 6-month period between May and September 1999, the staff and crew of the National Oceanic and Atmospheric Administration (NOAA) research ship R/V Ferrel augmented their activities to support a baseline fluorometry study for NOAA's Office of Response and Restoration (OR&R). During the study period, scientific data were collected at more than 50 stations in the Atlantic Ocean and Gulf of Mexico. The study was designed, in part, to assess the Special Monitoring of Applied Response Technologies (SMART) program. SMART is a joint U.S. Coast Guard (USCG), U.S. Environmental Protection Agency (EPA), Centers for Disease Control and Prevention (CDC), and NOAA monitoring program that provides near real-time feedback to the Unified Command during dispersant applications to mitigate marine oil spills. Using fluorometers to accurately measure dispersed oil concentrations is not a trivial task. Detector response values vary because of oil composition and oil weathering; dispersed oil is not in true solution; and natural waters contribute matrix effects and background fluorescence. It was the latter two that were investigated. Because seawater is a complex mixture of dissolved chemicals, particulates, and living plants and animals, archiving samples for future analysis relative to background fluorescence is problematic. Each contributes to background fluorescence and matrix effects when dispersed oil is present in the sample. Since water samples change with storage, only near real-time analyses are valid; therefore, using an at-sea laboratory like the NOAA's Ferrel was essential to the study design. Results suggest that the adverse flouorometry effects observed for open-ocean environments were within typical quality-objective goals. Therefore, the range of seawater composition changes observed in this investigation had very little effect on the ability to detect dispersed oil and meet the SMART mission objectives.
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Neiman, Paul J., Natalie Gaggini, Christopher W. Fairall, Joshua Aikins, J. Ryan Spackman, L. Ruby Leung, Jiwen Fan, Joseph Hardin, Nicholas R. Nalli, and Allen B. White. "An Analysis of Coordinated Observations from NOAA’s Ronald H. Brown Ship and G-IV Aircraft in a Landfalling Atmospheric River over the North Pacific during CalWater-2015." Monthly Weather Review 145, no. 9 (September 2017): 3647–69. http://dx.doi.org/10.1175/mwr-d-17-0055.1.
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To gain a more complete observational understanding of atmospheric rivers (ARs) over the data-sparse open ocean, a diverse suite of mobile observing platforms deployed on NOAA’s R/V Ronald H. Brown ( RHB) and G-IV research aircraft during the CalWater-2015 field campaign was used to describe the structure and evolution of a long-lived AR modulated by six frontal waves over the northeastern Pacific during 20–25 January 2015. Satellite observations and reanalysis diagnostics provided synoptic-scale context, illustrating the warm, moist southwesterly airstream within the quasi-stationary AR situated between an upper-level trough and ridge. The AR remained offshore of the U.S. West Coast but made landfall across British Columbia where heavy precipitation fell. A total of 47 rawinsondes launched from the RHB provided a comprehensive thermodynamic and kinematic depiction of the AR, including uniquely documenting an upward intrusion of strong water vapor transport in the low-level moist southwesterly flow during the passage of frontal waves 2–6. A collocated 1290-MHz wind profiler showed an abrupt frontal transition from southwesterly to northerly flow below 1 km MSL coinciding with the tail end of AR conditions. Shipborne radar and disdrometer observations in the AR uniquely captured key microphysical characteristics of shallow warm rain, convection, and deep mixed-phase precipitation. Novel observations of sea surface fluxes in a midlatitude AR documented persistent ocean surface evaporation and sensible heat transfer into the ocean. The G-IV aircraft flew directly over the ship, with dropsonde and radar spatial analyses complementing the temporal depictions of the AR from the RHB. The AR characteristics varied, depending on the location of the cross section relative to the frontal waves.
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Pichugina, Yelena L., Robert M. Banta, Joseph B. Olson, Jacob R. Carley, Melinda C. Marquis, W. Alan Brewer, James M. Wilczak, et al. "Assessment of NWP Forecast Models in Simulating Offshore Winds through the Lower Boundary Layer by Measurements from a Ship-Based Scanning Doppler Lidar." Monthly Weather Review 145, no. 10 (October 2017): 4277–301. http://dx.doi.org/10.1175/mwr-d-16-0442.1.
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Evaluation of model skill in predicting winds over the ocean was performed by comparing retrospective runs of numerical weather prediction (NWP) forecast models to shipborne Doppler lidar measurements in the Gulf of Maine, a potential region for U.S. coastal wind farm development. Deployed on board the NOAA R/V Ronald H. Brown during a 2004 field campaign, the high-resolution Doppler lidar (HRDL) provided accurate motion-compensated wind measurements from the water surface up through several hundred meters of the marine atmospheric boundary layer (MABL). The quality and resolution of the HRDL data allow detailed analysis of wind flow at heights within the rotor layer of modern wind turbines and data on other critical variables to be obtained, such as wind speed and direction shear, turbulence, low-level jet properties, ramp events, and many other wind-energy-relevant aspects of the flow. This study will focus on the quantitative validation of NWP models’ wind forecasts within the lower MABL by comparison with HRDL measurements. Validation of two modeling systems rerun in special configurations for these 2004 cases—the hourly updated Rapid Refresh (RAP) system and a special hourly updated version of the North American Mesoscale Forecast System [NAM Rapid Refresh (NAMRR)]—are presented. These models were run at both normal-resolution (RAP, 13 km; NAMRR, 12 km) and high-resolution versions: the NAMRR-CONUS-nest (4 km) and the High-Resolution Rapid Refresh (HRRR, 3 km). Each model was run twice: with (experimental runs) and without (control runs) assimilation of data from 11 wind profiling radars located along the U.S. East Coast. The impact of the additional assimilation of the 11 profilers was estimated by comparing HRDL data to modeled winds from both runs. The results obtained demonstrate the importance of high-resolution lidar measurements to validate NWP models and to better understand what atmospheric conditions may impact the accuracy of wind forecasts in the marine atmospheric boundary layer. Results of this research will also provide a first guess as to the uncertainties of wind resource assessment using NWP models in one of the U.S. offshore areas projected for wind plant development.
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Sommariva, R., H. D. Osthoff, S. S. Brown, T. S. Bates, T. Baynard, D. Coffman, J. A. de Gouw, et al. "Radicals in the marine boundary layer during NEAQS 2004: a model study of day-time and night-time sources and sinks." Atmospheric Chemistry and Physics 9, no. 9 (May 13, 2009): 3075–93. http://dx.doi.org/10.5194/acp-9-3075-2009.
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Abstract. This paper describes a modelling study of several HOx and NOx species (OH, HO2, organic peroxy radicals, NO3 and N2O5) in the marine boundary layer. A model based upon the Master Chemical Mechanism (MCM) was constrained to observations of chemical and physical parameters made onboard the NOAA ship R/V Brown as part of the New England Air Quality Study (NEAQS) in the summer of 2004. The model was used to calculate [OH] and to determine the composition of the peroxy radical pool. Modelled [NO3] and [N2O5] were compared to in-situ measurements by Cavity Ring-Down Spectroscopy. The comparison showed that the model generally overestimated the measurements by 30–50%, on average. The model results were analyzed with respect to several chemical and physical parameters, including uptake of NO3 and N2O5 on fog droplets and on aerosol, dry deposition of NO3 and N2O5, gas-phase hydrolysis of N2O5 and reactions of NO3 with NMHCs and peroxy radicals. The results suggest that fog, when present, is an important sink for N2O5 via rapid heterogeneous uptake. The comparison between the model and the measurements were consistent with values of the heterogeneous uptake coefficient of N2O5 (γN2O5)>1×10−2, independent of aerosol composition in this marine environment. The analysis of the different loss processes of the nitrate radical showed the important role of the organic peroxy radicals, which accounted for a significant fraction (median: 15%) of NO3 gas-phase removal, particularly in the presence of high concentrations of dimethyl sulphide (DMS).
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O'Sullivan, N., and B. Ward. "Mapping flow distortion on oceanographic platforms using computational fluid dynamics." Ocean Science Discussions 9, no. 6 (November 9, 2012): 3485–520. http://dx.doi.org/10.5194/osd-9-3485-2012.
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Abstract. Ocean-Atmosphere Fluxes Eddy correlation (EC) is the most direct method to measure fluxes of trace gases over the Earth's surface. In its simplest form, an EC setup consists of a gas sensor and a sonic anemometer. EC is commonly used on land, but its adaptation at sea has proven difficult because of the marine environment, the motion of the research platform (ship or buoy), and flow distortion. Flow distortion occurs when streamlines circumvent the research platform, which may lead to significant errors in the calculation of the gas transfer velocity. This paper uses computational fluid dynamics (CFD) to simulate the errors in wind speed measurements caused by flow distortion on the R/V Celtic Explorer. Numerical measurements were obtained from the finite volume CFD code OpenFOAM, which was used to simulate the velocity fields. This was done over a range of orientations in the test domain from −60° to +60°, in increments of 10°. The simulation was also set up for a range of velocities, ranging from 5 m s−1 to 25 m s−1 in increments of 0.5 m s−1 The numerical analysis showed close agreement to experimental measurements to within a 12% mean difference prediction of flow distortion effects. Other aspects resulting from flow distortion that were investigated using the CFD tools included development of a correction method for flow distortion effects for in situ wind speed measurements; analysis of ideal positioning of anemometers; vertical tilt orientation of the vessel to inflow; meteorological mast design; and mast instrumentation setups.
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Sommariva, R., H. D. Osthoff, S. S. Brown, T. S. Bates, T. Baynard, D. Coffman, J. A. de Gouw, et al. "Radicals in the marine boundary layer during NEAQS 2004: a model study of day-time and night-time sources and sinks." Atmospheric Chemistry and Physics Discussions 8, no. 4 (September 3, 2008): 16643–92. http://dx.doi.org/10.5194/acpd-8-16643-2008.
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Abstract. This paper describes a modelling study of several HOx and NOx species (OH, HO2, organic peroxy radicals, NO3 and N2O5) in the marine boundary layer. A model based upon the Master Chemical Mechanism (MCM) was constrained to observations of chemical and physical parameters made onboard the NOAA ship R/V Brown as part of the New England Air Quality Study (NEAQS) in the summer of 2004. The model was used to calculate [OH] and to determine the composition of the peroxy radical pool. Modelled [NO3] and [N2O5] were compared to in-situ measurements by Cavity Ring-Down Spectroscopy. The comparison showed that the model generally overestimated the measurements by 30–50%, on average. The model results were analyzed with respect to several chemical and physical parameters, including uptake of NO3 and N2O5 on fog droplets and on aerosol, dry deposition of NO3 and N2O5, gas-phase hydrolysis of N2O5 and reactions of NO3 with NMHCs and peroxy radicals. The results suggest that fog, when present, is an important sink for N2O5 via rapid heterogeneous uptake. The comparison between the model and the measurements were consistent with values of the heterogeneous uptake coefficient of N2O5 (γN2O5)>1×10−2, independent of aerosol composition in this marine environment. The analysis of the different loss processes of the nitrate radical showed the important role of the organic peroxy radicals, which accounted for a significant fraction (median: 15%) of NO3 gas-phase removal, particularly in the presence of high concentrations of dimethyl sulphide (DMS).