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1
Cantwell, John, et Pilar Barrera. « Intercompany Agreements for Technological Development ». International Studies of Management & ; Organization 25, no 1-2 (mars 1995) : 75–95. http://dx.doi.org/10.1080/00208825.1995.11656652.
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Murray, Laura, et Darrel H. Pearson. « The Landmark Decision in Jockey Canada Company v. President of Canada Border Services Agency : Lessons for Compliance with Canadian Customs Valuation Requirements ». Global Trade and Customs Journal 8, Issue 7/8 (1 juillet 2013) : 209–16. http://dx.doi.org/10.54648/gtcj2013029.
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This paper analyses the reasons for the Canadian International Trade Tribunal's decision in Jockey Canada Company v. President of Canada Border Services Agency respecting Canadian customs valuation compliance in related party cross-border transactions. It offers practical insights into the precautions that should be taken by multinational companies when structuring import transactions in order to satisfy their evidentiary burden to prove the accuracy of declared values for duty, including the maintenance of probative supporting documentary evidence and the need for customs valuation oriented contemporaneous documentation such as granular transfer pricing studies and agreements between related parties that discretely cover intercompany payments. The application of the transaction value method when pricing is based on a formulaic transfer pricing policy is also examined.
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Vasiljević, Mirko. « Arbitration agreement and intercompany disputes ». Anali Pravnog fakulteta u Beogradu, no 2/2018 (14 juillet 2018) : 7–46. http://dx.doi.org/10.51204/anali_pfub_18201a.
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The affirmation of resolution through arbitration of commercial disputes in the field of contract law, both at national levels (as an undisputable trend of varying degrees) as well as at the international level, has raised the issue of the possibility of resolving intercompany disputes in this manner, in order to extend the freedom of will of investors from the domain of establishing companies to include the domain of the freedom of choice of a forum for resolving possible disputes arising from numerous legal relations of this kind. However, unlike contracts, with the primacy of free will compared to limitations (the relation of rules and exceptions), the sphere of intercompany relations, although basically contractual by its origin, has, in its functioning, an emphasized need to resolve the conflict of contract and company law in order to make the arbitrability of these disputes realistically possible, while on the other hand, compared to the contract law, the sphere of company law is always more in the focus of attention of national public orders, as a universal institute (regardless of its scope), which represents an obstacle to arbitrability of these disputes. In this paper, the author first analyses the legal nature of the constituent acts of companies (the founding act and statute of a joint stock company) in the context of an arbitration agreement, on which the arbitrability of intercompany disputes can solely be based, finding that their contractual nature is a serious obstacle to mandatory arbitrations of these disputes (if these acts with this clause are adopted by majority of votes), and that the theory of adhesion contracts could be a solution to encourage arbitrability, but only for closed type of companies, while this would not be possible in the case of a public joint stock company, especially in the case of non-professional shareholders because of the need to additionally protect them through consumer law. The author continues by analysing the notion of intercompany disputes and systems of possible objective arbitrability (ratione materiae) of these disputes, finding that the Serbian arbitration law and company law, especially with regard to the possible restrictive concept of „exclusive jurisdiction of commercial courts“ for these disputes, has at least serious reasons for changes in favour of strengthening their arbitrability, with certain necessary individual exclusions in case of the dominance of public order interest. Finally, the author also analyses certain aspects of multiparty nature of the intercompany disputes, especially regarding public joint stock companies, as possible procedural obstacles to their resolution through arbitration, even in cases of their possibly undisputable objective arbitrability.
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Vasiljević, Mirko. « Arbitration agreement and intercompany disputes ». Anali Pravnog fakulteta u Beogradu 66, no 2 (2018) : 7–46. http://dx.doi.org/10.5937/alanipfb1802007v.
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Kowalczyk, Tamara K., et H. Lynn Stallworth. « Rex Seafood, Incorporated : Accounting for Inventory Transactions among Related Parties ». Issues in Accounting Education 32, no 1 (1 novembre 2015) : 33–41. http://dx.doi.org/10.2308/iace-51331.
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ABSTRACT This case is based on an actual inventory accounting dilemma for a fish processing company located in Washington State. Rex Seafood, Incorporated (Rex) and its wholly owned subsidiary, Juneau Supply Company, purchase, process, and sell fish to restaurants and other retail outlets in the state of Washington and surrounding inland states. Rex has an agreement with Condor Enterprises to transport fish purchased from Juneau Supply in Alaska to Rex's facility in Washington for processing. The central issue of the case involves appropriate accounting and reporting for intercompany sales: How should the sales of inventory from Juneau Supply to Condor and the purchases by Rex from Condor be recorded and reported? Using the FASB Accounting Standards Codification, students must determine whether Rex's arrangement with Condor is a product financing arrangement, whether the purchases and sales of inventory should be considered a single exchange transaction, and whether the events should be considered intercompany transactions. In addition, students are asked to consider recording and disclosure implications of recommended solutions. This case is suitable for use in undergraduate Intermediate and graduate Financial Accounting classes.
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Salva, Jean-marie. « Customs Valuation and Transfer Pricing : ICC proposals ». EC Tax Review 25, Issue 5/6 (1 novembre 2016) : 346–51. http://dx.doi.org/10.54648/ecta2016034.
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Intercompany transactions account for more than 60% of global trade value. In this article, one can easily understand that the concept of transfer pricing is a major issue in the determination of customs valuation. However, the relationship between transfer pricing and customs valuation is not easy to grasp. Basically, there is two different approaches of transfer pricing, the first one adopted by tax agencies, based on the OECD Transfer Pricing Guidelines and the second adopted by customs agencies, based on the WTO Customs valuation Agreement (CVA). From the business perspective, the divergence between the two taxation regimes is an obstacle to the liberalization of trade and inhibits international development for companies. On another hand, the International Chamber of Commerce (ICC) strongly believes that the WTO CVA and the use of OECD guidelines are enough to settle the issue of customs valuation and transfer pricing. However, ICC specifies that tax and customs approaches of intercompany transactions should converge to the same value. In this goal, ICC published a policy statement in 2012, which has been integrated in the WCO guidelines. This statement, based on the harmonization of the current rules, contains several additional options to derive customs value. Also we can regret that the Union Customs Code (UCC) does not contain any evolution from a transfer pricing perspective but contains some negatives changes regarding custom valuation. Also, the opportunity of the WCO Free Trade Agreement (FTA) should be taken to move forward on this issue.
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Olika, Daniel, et Ilemobade Olateru-Olagbegi. « Assessing the Transfer Pricing Disputes Framework in Nigeria ». Business Law Review 43, Issue 2 (1 avril 2022) : 65–76. http://dx.doi.org/10.54648/bula2022010.
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Transfer pricing, from documentation to audit, can be complicated and costly. Despite the release of transfer pricing regulations and increased scrutiny over intercompany dealings, the revenue authorities and taxpayers still disagree over various aspects of transfer pricing documentation. This situation necessitated the creation of various transfer pricing dispute resolution and dispute prevention mechanisms in jurisdictions across the globe. The Organization for Economic Cooperation and Development (OECD) has set the global standards on the mechanisms for transfer pricing dispute resolution/prevention and how they should apply. These transfer pricing dispute prevention mechanisms seek to avoid the costly and complicated process that is associated with transfer pricing audit while the transfer pricing dispute resolution mechanisms seek to resolve transfer pricing disputes in the most efficient manner. Accordingly, this article seeks to assess the transfer pricing dispute resolution/prevention framework in Nigeria against the global standards for resolving and preventing transfer pricing disputes. Transfer pricing, safe harbour, advanced pricing arrangement, mutual agreement procedure, dispute resolution, dispute prevention
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Fabio, Massimo. « Customs Value and Transfer Pricing : WCO and ICC Solutions to Be Adopted by Customs Authorities ». Global Trade and Customs Journal 15, Issue 6 (1 juin 2020) : 273–87. http://dx.doi.org/10.54648/gtcj2020069.
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Intercompany transactions represent nowadays more than 60% of the total market. Businesses dealing with cross-border trade need to comply with the Transfer Pricing (TP) rules for income tax purposes and are obliged to reconcile transfer pricing adjustment with customs value. Such a reconciliation under the traditional customs approach is really burdensome. Just recently, World Customs Organization (WCO) took note of this issue and invited all customs authorities to apply the International Chamber of Commerce (ICC) solutions to ease the customs relation and speed the international trade. The modern approach implies to integrate the TP documentation with a customs dedicated section, establish a transparent discussion with the customs offices and finalize an agreement. It will be the best way to set an effective TP/customs procedure, in any country impacted by the application of the TP policy, to apply the best reconciliation mitigating the administrative costs and neutralizing any risk of sanction in the global marketplace.
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Lait, L. R., P. A. Newman, M. R. Schoeberl, T. McGee, L. Twigg, E. V. Browell, M. A. Fenn et al. « Non-coincident inter-instrument comparisons of ozone measurements using quasi-conservative coordinates ». Atmospheric Chemistry and Physics Discussions 4, no 4 (5 août 2004) : 4383–406. http://dx.doi.org/10.5194/acpd-4-4383-2004.
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Abstract. Ozone measurements from ozonesondes, AROTAL, DIAL, and POAM III instruments during the SOLVE-2/VINTERSOL period are composited in a time-varying, flow-following quasi-conservative (PV-θ) coordinate space; the resulting composites from each instrument are mapped onto the other instruments' locations and times. The mapped data are then used to intercompare data from the different instruments. Overall, the four ozone data sets are found to be in good agreement. AROTAL shows somewhat lower values below 16 km, and DIAL has a positive bias at the upper limits of its altitude range. These intercomparisons are consistent with those obtained from more conventional near-coincident profiles, where available. Although the PV-θ mapping technique entails larger uncertainties of individual profile differences compared to direct near-coincident comparisons, the ability to include much larger numbers of comparisons can make this technique advantageous.
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Lait, L. R., P. A. Newman, M. R. Schoeberl, T. McGee, L. Twigg, E. V. Browell, M. A. Fenn et al. « Non-coincident inter-instrument comparisons of ozone measurements using quasi-conservative coordinates ». Atmospheric Chemistry and Physics 4, no 9/10 (30 novembre 2004) : 2345–52. http://dx.doi.org/10.5194/acp-4-2345-2004.
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Abstract. Ozone measurements from ozonesondes, AROTAL, DIAL, and POAM III instruments during the SOLVE-2/VINTERSOL period are composited in a time-varying, flow-following quasi-conservative (PV-θ) coordinate space; the resulting composites from each instrument are mapped onto the other instruments' locations and times. The mapped data are then used to intercompare data from the different instruments. Overall, the four ozone data sets are found to be in good agreement. AROTAL shows somewhat lower values below 16 km, and DIAL has a positive bias at the upper limits of its altitude range. These intercomparisons are consistent with those obtained from more conventional near-coincident profiles, where available. Although the PV-θ mapping technique entails larger uncertainties of individual profile differences compared to direct near-coincident comparisons, the ability to include much larger numbers of comparisons can make this technique advantageous.
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Sharman, R., C. Tebaldi, G. Wiener et J. Wolff. « An Integrated Approach to Mid- and Upper-Level Turbulence Forecasting ». Weather and Forecasting 21, no 3 (1 juin 2006) : 268–87. http://dx.doi.org/10.1175/waf924.1.
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Abstract An automated procedure for forecasting mid- and upper-level turbulence that affects aircraft is described. This procedure, termed the Graphical Turbulence Guidance system, uses output from numerical weather prediction model forecasts to derive many turbulence diagnostics that are combined as a weighted sum with the relative weights computed to give best agreement with the most recent available turbulence observations (i.e., pilot reports of turbulence or PIREPs). This procedure minimizes forecast errors due to uncertainties in individual turbulence diagnostics and their thresholds. Thorough statistical verification studies have been performed that focused on the probabilities of correct detections of yes and no PIREPs by the forecast algorithm. Using these statistics as a guide, the authors have been able to intercompare individual diagnostic performance, and test various diagnostic threshold and weighting strategies. The overall performance of the turbulence forecast and the effect of these strategies on performance are described.
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Singer, Clare E., Benjamin W. Clouser, Sergey M. Khaykin, Martina Krämer, Francesco Cairo, Thomas Peter, Alexey Lykov et al. « Intercomparison of upper tropospheric and lower stratospheric water vapor measurements over the Asian Summer Monsoon during the StratoClim campaign ». Atmospheric Measurement Techniques 15, no 16 (23 août 2022) : 4767–83. http://dx.doi.org/10.5194/amt-15-4767-2022.
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Abstract. In situ measurements in the climatically important upper troposphere–lower stratosphere (UTLS) are critical for understanding controls on cloud formation, the entry of water into the stratosphere, and hydration–dehydration of the tropical tropopause layer. Accurate in situ measurement of water vapor in the UTLS however is difficult because of low water vapor concentrations (<5 ppmv) and a challenging low temperature–pressure environment. The StratoClim campaign out of Kathmandu, Nepal, in July and August 2017, which made the first high-altitude aircraft measurements in the Asian Summer Monsoon (ASM), also provided an opportunity to intercompare three in situ hygrometers mounted on the M-55 Geophysica: ChiWIS (Chicago Water Isotope Spectrometer), FISH (Fast In situ Stratospheric Hygrometer), and FLASH (Fluorescent Lyman-α Stratospheric Hygrometer). Instrument agreement was very good, suggesting no intrinsic technique-dependent biases: ChiWIS measures by mid-infrared laser absorption spectroscopy and FISH and FLASH by Lyman-α induced fluorescence. In clear-sky UTLS conditions (H2O<10 ppmv), mean and standard deviations of differences in paired observations between ChiWIS and FLASH were only (-1.4±5.9) % and those between FISH and FLASH only (-1.5±8.0) %. Agreement between ChiWIS and FLASH for in-cloud conditions is even tighter, at (+0.7±7.6) %. Estimated realized instrumental precision in UTLS conditions was 0.05, 0.2, and 0.1 ppmv for ChiWIS, FLASH, and FISH, respectively. This level of accuracy and precision allows the confident detection of fine-scale spatial structures in UTLS water vapor required for understanding the role of convection and the ASM in the stratospheric water vapor budget.
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Nino Samchkuashvili, Nino Samchkuashvili. « Peculiarities of Interaction Between Companies in the Conditions of Digital Economy ». Economics 105, no 8-10 (2 décembre 2023) : 87–100. http://dx.doi.org/10.36962/ecs105/8-10/2023-87.
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One of the characteristic features of the modern economy is the active development of various forms of interaction between companies. The methods of interaction between the participants in the market structures are changing due to the growing uncertainty of the external environment due to the increase in international competition, the globalization of the economy, and the acceleration of the processes of updating information technologies. The constant diffusion of markets, caused primarily by total networking and digitization, has significantly changed the nature of the company. Changes associated with the transition to the information society lead to increased integration at both the meso and macro levels. The purpose of the research is to determine the specificity of the process of interaction between companies in the conditions of the digital economy when the digitalization of economic activity is relevant. The contents of various theories of the development process of inter-company networks are differentiated, such as theories of stages, states, and connections. Five stages of the development of network relations are distinguished - processes of searching for connections, the initial stage of relations, the development of relations, maintenance of relations, and termination. The relationship between the development stages of the relationship and the types of interaction was determined: contact; joint production; cooperation; coordination; coevolution; and Consolidation. Adopting digital technologies to accelerate their technological evolution has been found to enable organizations to increase their competitive advantages. A model of economic activity is presented for the development of inter-company interaction in the conditions of digitalization. When forming intercompany interactions, the organization will be able to ensure their effectiveness: attracting interested parties for the purpose of interaction in solving a wide range of issues; Globalization of resources to create the possibility of managing the risks arising as a result of the complication of functioning tasks; By creating opportunities for action agreement and rapid knowledge generation among stakeholders at low cost. Scientific works aimed at studying the evolution of relations between economic entities are characterized by a variety of areas of analysis and justification of trends in the development of forms of interaction. However, it should be noted that most researchers believe that in modern conditions the most adequate option for the evolution of organizational forms are network structures. The literature review showed that elements of methodology borrowed from sociology, psychology, and socio-cultural anthropology allowed researchers to conduct studies of interactions between economic entities based on already existing basic conclusions and theoretical generalizations. In conclusion, the tasks of development of inter-company interaction in the conditions of digital economy and digitalization of economic activities are presented. Thus, in this article, network relations are proposed to be understood as a set of certain voluntary integration relations between independent economic entities operating according to agreed rules, the common long-term goal of which is the most efficient use of available resources, and also, when analyzing relations between economic entities, it would be advisable to pay more attention to the exchange of information and coordination of actions when mutually linking plans in the process of intercompany interactions. Key Words: Digital technologies, digitization of economic activity, digital economy, inter-company relations, coordination.
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Retegi, Jabier, et Juan Ignacio Igartua. « An analysis of the Mondragon case's competitiveness from a systemic perspective ». Intangible Capital 19, no 4 (25 septembre 2023) : 513. http://dx.doi.org/10.3926/ic.2261.
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Purpose: In this paper, the authors analyse some of the aspects that contribute to the better performance of Mondragon Corporation compared to other cooperatives and to the rest of the companies in the Basque Country from a systemic perspective.Design/methodology/approach: First, a systematic review of the literature on the factors that could explain the higher competitiveness of Mondragon Cooperatives compared to the rest of firms has been performed. Then, a draft framework representing the existing relationship between the factors has been proposed by the authors. Then, a contrast with five experts with different perspectives of Mondragon Corporation has been made. Finally, the contributions of the experts to the proposal has allowed to obtain a final framework.Findings: A framework is proposed that links and hierarchises the factors and establishes precondition relationships between them. This framework gives a special role to the basic intercooperative agreement structure as a condition to develop intercompany synergies. Research limitations/implications: The article analyses a very specific case such as Mondragon Corporation and the testing of the framework has been made by a limited number of experts/This research adds a new perspective to a rich literature on the factors that explain Mondragon Cooperatives competitiveness.Practical implications: This article gives insights into the factors that should be considered when trying to replicate the experience of Mondragon Corporation in other socioeconomic contexts.Social Implications: This research stresses the relevance of a shared set of values as a base for the construction of strong synergetic relations between companies.Originality/value: The existing literature related to the key factors for Mondragon Cooperatives’ competitiveness analysed them from an individual factor perspective. This research advances in the knowledge to understand the systemic interrelationship between them.
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Nawaz, M. Omar, Jeremiah Johnson, Greg Yarwood, Benjamin de Foy, Laura Judd et Daniel L. Goldberg. « An intercomparison of satellite, airborne, and ground-level observations with WRF–CAMx simulations of NO2 columns over Houston, Texas, during the September 2021 TRACER-AQ campaign ». Atmospheric Chemistry and Physics 24, no 11 (10 juin 2024) : 6719–41. http://dx.doi.org/10.5194/acp-24-6719-2024.
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Abstract. Nitrogen dioxide (NO2) is a precursor of ozone (O3) and fine particulate matter (PM2.5) – two pollutants that are above regulatory guidelines in many cities. Bringing urban areas into compliance of these regulatory standards motivates an understanding of the distribution and sources of NO2 through observations and simulations. The TRACER-AQ campaign, conducted in Houston, Texas, in September 2021, provided a unique opportunity to compare observed NO2 columns from ground-, airborne-, and satellite-based spectrometers. In this study, we investigate how these observational datasets compare and simulate column NO2 using WRF–CAMx with fine resolution (444 × 444 m2) comparable to the airborne column measurements. We compare WRF-simulated meteorology to ground-level monitors and find good agreement. We find that observations from the GEOstationary Coastal and Air Pollution Events (GEO-CAPE) Airborne Simulator (GCAS) instrument were strongly correlated (r2 = 0.79) to observations from Pandora spectrometers with a slight high bias (normalized mean bias (NMB) = 3.4 %). Remote sensing observations from the TROPOspheric Monitoring Instrument (TROPOMI) were generally well correlated with Pandora observations (r2 = 0.73) with a negative bias (NMB = −22.8 %). We intercompare different versions of TROPOMI data and find similar correlations across three versions but slightly different biases (from −22.8 % in v2.4.0 to −18.2 % in the NASA MINDS product). Compared with Pandora observations, the WRF–CAMx simulation had reduced correlation (r2 = 0.34) and a low bias (−21.2 %) over the entire study region. We find particularly poor agreement between simulated NO2 columns and GCAS-observed NO2 columns in downtown Houston, an area of high population and roadway densities. These findings point to a potential underestimate of NOx emissions (NOx = NO + NO2) from sources associated with the urban core of Houston, such as mobile sources, in the WRF–CAMx simulation driven by the Texas state inventory, and further investigation is recommended.
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McCarthy, D. D., Y. A. Yatskiv et G. A. Wilkins. « Report of Joint Meeting held on 1985 November 22 to consider the MERIT/COTES recommendations for a new international earth-rotation service ». Highlights of Astronomy 7 (1986) : 789–95. http://dx.doi.org/10.1017/s1539299600007309.
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AbstractA Joint Meeting of Commissions 19 and 31 was held during the IAU General Assembly at Delhi to consider the recommendations for a new international earth-rotation service put forward by the IAU/IUGG Joint Working Groups on the rotation of the Earth and the conventional terrestrial reference system. Wilkins gave summaries of the MERIT programme of activities to monitor earth rotation and intercompare the techniques of observation and analysis and of the COTES programme to establish the basis of a new conventional terrestrial reference system. He reviewed the recommendations of the Groups, and then introduced a draft resolution of the Commissions. An amendment on the continuation of the use of the technique of optical astrometry was accepted and the resolution was then adopted without objection. Four papers on work related to the MERIT/COTES programmes were then presented. Paquet discussed the agreement in the results by different techniques for polar motion and universal time. Preuss presented a paper by Campbell and Schuh on short-period variations in earth-rotation determined by VLBI. Dickey discussed the intercomparisons between the earth-orientation parameters obtained by different techniques and then reviewed the close correlation between the length of the day and the angular momentum of the atmosphere. Finally, Vicente and Verbeiren presented new techniques for processing time and polar motion series.
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Considine, D. B., D. J. Bergmann et H. Liu. « Sensitivity of Global Modeling Initiative chemistry and transport model simulations of radon-222 and lead-210 to input meteorological data ». Atmospheric Chemistry and Physics Discussions 5, no 4 (28 juillet 2005) : 5325–72. http://dx.doi.org/10.5194/acpd-5-5325-2005.
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Abstract. We have used the Global Modeling Initiative chemistry and transport model to simulate the radionuclides radon-222 and lead-210 using three different sets of input meteorological information: 1. Output from the Goddard Space Flight Center Global Modeling and Assimilation Office GEOS-STRAT assimilation; 2. Output from the Goddard Institute for Space Studies GISS II′ general circulation model; and 3. Output from the National Center for Atmospheric Research MACCM3 general circulation model. We intercompare these simulations with observations to determine the variability resulting from the different meteorological data used to drive the model, and to assess the agreement of the simulations with observations at the surface and in the upper troposphere/lower stratosphere region. The observational datasets we use are primarily climatologies developed from multiple years of observations. In the upper troposphere/lower stratosphere region, climatological distributions of lead-210 were constructed from ~25 years of aircraft and balloon observations compiled into the US Environmental Measurements Laboratory RANDAB database. Taken as a whole, no simulation stands out as superior to the others. However, the simulation driven by the NCAR MACCM3 meteorological data compares better with lead-210 observations in the upper troposphere/lower stratosphere region. Comparisons of simulations made with and without convection show that the role played by convective transport and scavenging in the three simulations differs substantially. These differences may have implications for evaluation of the importance of very short-lived halogen-containing species on stratospheric halogen budgets.
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Considine, D. B., D. J. Bergmann et H. Liu. « Sensitivity of Global Modeling Initiative chemistry and transport model simulations of radon-222 and lead-210 to input meteorological data ». Atmospheric Chemistry and Physics 5, no 12 (16 décembre 2005) : 3389–406. http://dx.doi.org/10.5194/acp-5-3389-2005.
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Abstract. We have used the Global Modeling Initiative chemistry and transport model to simulate the radionuclides radon-222 and lead-210 using three different sets of input meteorological information: 1. Output from the Goddard Space Flight Center Global Modeling and Assimilation Office GEOS-STRAT assimilation; 2. Output from the Goddard Institute for Space Studies GISS II' general circulation model; and 3. Output from the National Center for Atmospheric Research MACCM3 general circulation model. We intercompare these simulations with observations to determine the variability resulting from the different meteorological data used to drive the model, and to assess the agreement of the simulations with observations at the surface and in the upper troposphere/lower stratosphere region. The observational datasets we use are primarily climatologies developed from multiple years of observations. In the upper troposphere/lower stratosphere region, climatological distributions of lead-210 were constructed from ~25 years of aircraft and balloon observations compiled into the US Environmental Measurements Laboratory RANDAB database. Taken as a whole, no simulation stands out as superior to the others. However, the simulation driven by the NCAR MACCM3 meteorological data compares better with lead-210 observations in the upper troposphere/lower stratosphere region. Comparisons of simulations made with and without convection show that the role played by convective transport and scavenging in the three simulations differs substantially. These differences may have implications for evaluation of the importance of very short-lived halogen-containing species on stratospheric halogen budgets.
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Queißer, M., D. Granieri, M. Burton, A. La Spina, G. Salerno, R. Avino et L. Fiorani. « Intercomparing CO<sub>2</sub> ; amounts from dispersion modeling, 1.6 μm differential absorption lidar and open path FTIR at a natural CO<sub>2</sub> ; release at Caldara di Manziana, Italy ». Atmospheric Measurement Techniques Discussions 8, no 4 (29 avril 2015) : 4325–45. http://dx.doi.org/10.5194/amtd-8-4325-2015.
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Abstract. We intercompare results of three independent approaches to quantify a vented CO2 release at a strongly non-uniform CO2 Earth degassing at Caldara di Manziana, central Italy. An integrated path differential absorption lidar prototype and a commercial open path FTIR system were measuring column averaged CO2 concentrations in parallel at two different paths. An Eulerian gas dispersion model simulated 3-D CO2 concentration maps in the same area, using in situ CO2 flux input data acquired at 152 different points. Local processes the model does not account for, such as small-scale and short-lived wind eddies, govern CO2 concentrations in the instrument measurement paths. The model, on the other hand, also considers atmospheric effects that are out of the field of view of the instruments. Despite this we find satisfactory agreement between modeled and measured CO2 concentrations under certain meteorological conditions. Under these conditions the results suggest that an Eulerian dispersion model and optical remote sensing can be used as an integrated, complementary monitoring approach for CO2 hazard or leakage assessment. Furthermore, the modeling may assist in evaluating CO2 sensing surveys in the future. CO2 column amounts from differential absorption lidar are in line with those from FTIR for both paths with a mean residual of the time series of 44 and 34 ppm, respectively. This experiment is a fundamental step forward in the deployment of the differential absorption lidar prototype as a highly portable active remote sensing instrument probing vented CO2 emissions, including volcanoes.
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Gutiérrez, J. M., D. San-Martín, S. Brands, R. Manzanas et S. Herrera. « Reassessing Statistical Downscaling Techniques for Their Robust Application under Climate Change Conditions ». Journal of Climate 26, no 1 (1 janvier 2013) : 171–88. http://dx.doi.org/10.1175/jcli-d-11-00687.1.
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Abstract The performance of statistical downscaling (SD) techniques is critically reassessed with respect to their robust applicability in climate change studies. To this end, in addition to standard accuracy measures and distributional similarity scores, the authors estimate the robustness of the methods under warming climate conditions working with anomalous warm historical periods. This validation framework is applied to intercompare the performances of 12 different SD methods (from the analog, weather typing, and regression families) for downscaling minimum and maximum temperatures in Spain. First, a calibration of these methods is performed in terms of both geographical domains and predictor sets; the results are highly dependent on the latter, with optimum predictor sets including near-surface temperature data (in particular 2-m temperature), which appropriately discriminate cold episodes related to temperature inversion in the lower troposphere. Although regression methods perform best in terms of correlation, analog and weather generator approaches are more appropriate for reproducing the observed distributions, especially in case of wintertime minimum temperature. However, the latter two families significantly underestimate the temperature anomalies of the warm periods considered in this work. This underestimation is found to be critical when considering the warming signal in the late twenty-first century as given by a global climate model [the ECHAM5–Max Planck Institute (MPI) model]. In this case, the different downscaling methods provide warming values with differences in the range of 1°C, in agreement with the robustness significance values. Therefore, the proposed test is a promising technique for detecting lack of robustness in statistical downscaling methods applied in climate change studies.
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Jarugula, Sreelekha, Severine Fournier, J. T. Reager et Madeleine Pascolini-Campbell. « Intercomparison of In Situ and Satellite Sea Surface Salinity Products for Global Coastal Ocean Studies ». Journal of Atmospheric and Oceanic Technology 42, no 1 (janvier 2025) : 3–16. https://doi.org/10.1175/jtech-d-23-0168.1.
Texte intégralRésumé :
Abstract Observing coastal ocean salinity is crucial for understanding the physical and biological processes impacting ocean circulation, ecosystems, and the hydrological cycle. We perform a thorough comparison between in situ and satellite sea surface salinity (SSS) products with a focus on global coastal ocean. Between 40 and 500 km from the coastline, we intercompare SSS from more than two million World Ocean Database (WOD) salinity profiles, gridded Argo data, and satellite products: NASA Multimission Optimally Interpolated Sea Surface Salinity (OISSS), 40- and 70-km Remote Sensing Systems (REMSS) Soil Moisture Active Passive (SMAP), Jet Propulsion Laboratory (JPL) SMAP, Laboratory of Oceanography and Climate: Experiments and Numerical Approaches (LOCEAN) Soil Moisture Ocean Salinity (SMOS), and European Space Agency (ESA) Climate Change Initiative (CCI) salinity. We find good agreement between the satellite products and in situ data with satellite-in situ mean differences (0.5–1.7 pss, where pss is the Practical Salinity Scale), root-mean-square differences (0.5–2.4 pss), and signal-to-noise ratios (1–3.8) generally decreasing at a faster rate from 40- to 100-km distance to the coast and remaining constant past 100 km. NASA OISSS, ESA CCI, 70-km REMSS SMAP, and LOCEAN SMOS have minimum differences with in situ observations. Empirical orthogonal function (EOF) analysis shows that all the satellite and in situ SSS compare well in capturing mode-1 and mode-2 seasonal variability but have notable differences in the amplitude of the mode-3 semiannual variability in coastal SSS. This study has implications for validation and improvement of satellite SSS and emphasizes the need for designing future satellite missions to better resolve the coastal salinity.
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Fahey, D. W., R. S. Gao, O. Möhler, H. Saathoff, C. Schiller, V. Ebert, M. Krämer et al. « The AquaVIT-1 intercomparison of atmospheric water vapor measurement techniques ». Atmospheric Measurement Techniques 7, no 9 (26 septembre 2014) : 3177–213. http://dx.doi.org/10.5194/amt-7-3177-2014.
Texte intégralRésumé :
Abstract. The AquaVIT-1 intercomparison of atmospheric water vapor measurement techniques was conducted at the aerosol and cloud simulation chamber AIDA (Aerosol Interaction and Dynamics in the Atmosphere) at the Karlsruhe Institute of Technology, Germany, in October 2007. The overall objective was to intercompare state-of-the-art and prototype atmospheric hygrometers with each other and with independent humidity standards under controlled conditions. This activity was conducted as a blind intercomparison with coordination by selected referees. The effort was motivated by persistent discrepancies found in atmospheric measurements involving multiple instruments operating on research aircraft and balloon platforms, particularly in the upper troposphere and lower stratosphere, where water vapor reaches its lowest atmospheric values (less than 10 ppm). With the AIDA chamber volume of 84 m3, multiple instruments analyzed air with a common water vapor mixing ratio, by extracting air into instrument flow systems, by locating instruments inside the chamber, or by sampling the chamber volume optically. The intercomparison was successfully conducted over 10 days during which pressure, temperature, and mixing ratio were systematically varied (50 to 500 hPa, 185 to 243 K, and 0.3 to 152 ppm). In the absence of an accepted reference instrument, the absolute accuracy of the instruments was not established. To evaluate the intercomparison, the reference value was taken to be the ensemble mean of a core subset of the measurements. For these core instruments, the agreement between 10 and 150 ppm of water vapor is considered good with variation about the reference value of about ±10% (±1σ). In the region of most interest between 1 and 10 ppm, the core subset agreement is fair with variation about the reference value of ±20% (±1σ). The upper limit of precision was also derived for each instrument from the reported data. The implication for atmospheric measurements is that the substantially larger differences observed during in-flight intercomparisons stem from other factors associated with the moving platforms or the non-laboratory environment. The success of AquaVIT-1 provides a template for future intercomparison efforts with water vapor or other species that are focused on improving the analytical quality of atmospheric measurements on moving platforms.
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Fahey, D. W., R. S. Gao, O. Möhler, H. Saathoff, C. Schiller, V. Ebert, M. Krämer et al. « The AquaVIT-1 intercomparison of atmospheric water vapor measurement techniques ». Atmospheric Measurement Techniques Discussions 7, no 4 (1 avril 2014) : 3159–251. http://dx.doi.org/10.5194/amtd-7-3159-2014.
Texte intégralRésumé :
Abstract. The AquaVIT-1 Intercomparison of Atmospheric Water Vapor Measurement Techniques was conducted at the aerosol and cloud simulation chamber AIDA at the Karlsruhe Institute of Technology, Germany, in October 2007. The overall objective was to intercompare state-of-the-art and prototype atmospheric hygrometers with each other and with independent humidity standards under controlled conditions. This activity was conducted as a blind intercomparison with coordination by selected referees. The effort was motivated by persistent discrepancies found in atmospheric measurements involving multiple instruments operating on research aircraft and balloon platforms, particularly in the upper troposphere and lower stratosphere where water vapor reaches its lowest atmospheric values (less than 10 ppm). With the AIDA chamber volume of 84 m3, multiple instruments analyzed air with a common water vapor mixing ratio, either by extracting air into instrument flow systems, locating instruments inside the chamber, or sampling the chamber volume optically. The intercomparison was successfully conducted over 10 days during which pressure, temperature, and mixing ratio were systematically varied (50 to 500 hPa, 185 to 243 K, and 0.3 to 152 ppm). In the absence of an accepted reference instrument, the reference value was taken to be the ensemble mean of a core subset of the measurements. For these core instruments, the agreement between 10 and 150 ppm of water vapor is considered good with variation about the reference value of about ±10% (±1σ). In the region of most interest between 1 and 10 ppm, the core subset agreement is fair with variation about the reference value of ±20% (±1σ). The upper limit of precision was also derived for each instrument from the reported data. These results indicate that the core instruments, in general, have intrinsic skill to determine unknown water vapor mixing ratios with an accuracy of at least ±20%. The implication for atmospheric measurements is that the substantially larger differences observed during in-flight intercomparisons stem from other factors associated with the moving platforms or the non-laboratory environment. The success of AquaVIT-1 provides a template for future intercomparison efforts with water vapor or other species that are focused on improving the analytical quality of atmospheric measurements on moving platforms.
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Hocke, Klemens, Leonie Bernet, Wenyue Wang, Christian Mätzler, Maxime Hervo et Alexander Haefele. « Integrated Water Vapor during Rain and Rain-Free Conditions above the Swiss Plateau ». Climate 9, no 7 (25 juin 2021) : 105. http://dx.doi.org/10.3390/cli9070105.
Texte intégralRésumé :
Water vapor column density, or vertically-integrated water vapor (IWV), is monitored by ground-based microwave radiometers (MWR) and ground-based receivers of the Global Navigation Satellite System (GNSS). For rain periods, the retrieval of IWV from GNSS Zenith Wet Delay (ZWD) neglects the atmospheric propagation delay of the GNSS signal by rain droplets. Similarly, it is difficult for ground-based dual-frequency single-polarisation microwave radiometers to separate the microwave emission of water vapor and cloud droplets from the rather strong microwave emission of rain. For ground-based microwave radiometry at Bern (Switzerland), we take the approach that IWV during rain is derived from linearly interpolated opacities before and after the rain period. The intermittent rain periods often appear as spikes in the time series of integrated liquid water (ILW) and are indicated by ILW ≥0.4 mm. In the present study, we assume that IWV measurements from radiosondes are not affected by rain. We intercompare the climatologies of IWV(rain), IWV(no rain), and IWV(all) obtained by radiosonde, ground-based GNSS atmosphere sounding, ground-based MWR, and ECMWF reanalysis (ERA5) at Payerne and Bern in Switzerland. In all seasons, IWV(rain) is 3.75 to 5.94 mm greater than IWV(no rain). The mean IWV differences between GNSS and radiosonde at Payerne are less than 0.26 mm. The datasets at Payerne show a better agreement than the datasets at Bern. However, the MWR at Bern agrees with the radiosonde at Payerne within 0.41 mm for IWV(rain) and 0.02 mm for IWV(no rain). Using the GNSS and rain gauge measurements at Payerne, we find that IWV(rain) increases with increase of the precipitation rate during summer as well as during winter. IWV(rain) above the Swiss Plateau is quite well estimated by GNSS and MWR though the standard retrievals are limited or hampered during rain periods.
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Ladstädter, F., A. K. Steiner, M. Schwärz et G. Kirchengast. « Climate intercomparison of GPS radio occultation, RS90/92 radiosondes and GRUAN from 2002 to 2013 ». Atmospheric Measurement Techniques 8, no 4 (23 avril 2015) : 1819–34. http://dx.doi.org/10.5194/amt-8-1819-2015.
Texte intégralRésumé :
Abstract. Observations from the GPS radio occultation (GPSRO) satellite technique and from the newly established GCOS Reference Upper Air Network (GRUAN) are both candidates to serve as reference observations in the Global Climate Observing System (GCOS). Such reference observations are key to decrease existing uncertainties in upper-air climate research. There are now more than 12 years of data available from GPSRO, with the recognized properties high accuracy, global coverage, high vertical resolution, and long-term stability. These properties make GPSRO a suitable choice for comparison studies with other upper-air observational systems. The GRUAN network consists of reference radiosonde ground stations (16 at present), which adhere to the GCOS climate monitoring principles. In this study, we intercompare GPSRO temperature and humidity profiles and Vaisala RS90/92 data from the "standard" global radiosonde network over the whole 2002 to 2013 time frame. Additionally, we include the first years of GRUAN data (using Vaisala RS92), available since 2009. GPSRO profiles which occur within 3 h and 300 km of radiosonde launches are used. Overall very good agreement is found between all three data sets with temperature differences usually less than 0.2 K. In the stratosphere above 30 hPa, temperature differences are larger but still within 0.5 K. Day/night comparisons with GRUAN data reveal small deviations likely related to a warm bias of the radiosonde data at high altitudes, but also residual errors from the GPSRO retrieval process might play a role. Vaisala RS90/92 specific humidity exhibits a dry bias of up to 40% in the upper troposphere, with a smaller bias at lower altitudes within 15%. GRUAN shows a marked improvement in the bias characteristics, with less than 5% difference to GPSRO, up to 300 hPa. GPSRO dry temperature and physical temperature are validated using radiosonde data as reference. We find that GPSRO provides valuable long-term stable reference observations with well-defined error characteristics for climate applications and for anchoring other upper-air measurements.
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Ladstädter, F., A. K. Steiner, M. Schwärz et G. Kirchengast. « Climate intercomparison of GPS radio occultation, RS90/92 radiosondes and GRUAN over 2002 to 2013 ». Atmospheric Measurement Techniques Discussions 7, no 11 (25 novembre 2014) : 11735–69. http://dx.doi.org/10.5194/amtd-7-11735-2014.
Texte intégralRésumé :
Abstract. Observations from the GPS radio occultation (GPSRO) satellite technique and from the newly established GCOS Reference Upper Air Network (GRUAN) are both candidates to serve as reference observations in the Global Climate Observing System (GCOS). Such reference observations are key to decrease existing uncertainties in upper-air climate research. There are now more than 12 years of data available from GPSRO, with the recognized properties high accuracy, global coverage, high vertical resolution, and long-term stability. These properties make GPSRO a suitable choice for comparison studies with other upper-air observational systems. The GRUAN network consists of reference radiosonde ground stations (16 at present), which adhere to the GCOS climate monitoring principles. In this study, we intercompare GPSRO temperature and humidity profiles and Vaisala RS90/92 data from the "standard" global radiosonde network over the whole 2002 to 2013 time frame. Additionally, we include the first years of GRUAN data (using Vaisala RS92), available since 2009. GPSRO profiles which occur within 3 h and 300 km of radiosonde launches are used. Very good agreement is found between all three datasets with temperature differences usually less than 0.2 K. In the stratosphere above 30 hPa, temperature differences are larger but still within 0.5 K. Day/night comparisons with GRUAN data reveal small deviations likely related to a warm bias of the radiosonde data at high altitudes, but also residual errors from the GPSRO retrieval process might play a role. Vaisala RS90/92 specific humidity exhibits a dry bias of up to 40% in the upper troposphere, with a smaller bias at lower altitudes within 15%. GRUAN shows a marked improvement in the bias characteristics, with less than 5% difference to GPSRO up to 300 hPa. GPSRO dry temperature and physical temperature are validated using radiosonde data as reference. We find that GPSRO provides valuable long-term stable reference observations with well-defined error characteristics for climate applications and for anchoring other upper-air measurements.
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Vinukollu, Raghuveer K., Justin Sheffield, Eric F. Wood, Michael G. Bosilovich et David Mocko. « Multimodel Analysis of Energy and Water Fluxes : Intercomparisons between Operational Analyses, a Land Surface Model, and Remote Sensing ». Journal of Hydrometeorology 13, no 1 (1 février 2012) : 3–26. http://dx.doi.org/10.1175/2011jhm1372.1.
Texte intégralRésumé :
Abstract Using data from seven global model operational analyses (OA), one land surface model, and various remote sensing retrievals, the energy and water fluxes over global land areas are intercompared for 2003/04. Remote sensing estimates of evapotranspiration (ET) are obtained from three process-based models that use input forcings from multisensor satellites. An ensemble mean (linear average) of the seven operational (mean-OA) models is used primarily to intercompare the fluxes with comparisons performed at both global and basin scales. At the global scale, it is found that all components of the energy budget represented by the ensemble mean of the OA models have a significant bias. Net radiation estimates had a positive bias (global mean) of 234 MJ m−2 yr−1 (7.4 W m−2) as compared to the remote sensing estimates, with the latent and sensible heat fluxes biased by 470 MJ m−2 yr−1 (13.3 W m−2) and −367 MJ m−2 yr−1 (11.7 W m−2), respectively. The bias in the latent heat flux is affected by the bias in the net radiation, which is primarily due to the biases in the incoming shortwave and outgoing longwave radiation and to the nudging process of the operational models. The OA models also suffer from improper partitioning of the surface heat fluxes. Comparison of precipitation (P) analyses from the various OA models, gauge analysis, and remote sensing retrievals showed better agreement than the energy fluxes. Basin-scale comparisons were consistent with the global-scale results, with the results for the Amazon in particular showing disparities between OA and remote sensing estimates of energy fluxes. The biases in the fluxes are attributable to a combination of errors in the forcing from the OA atmospheric models and the flux calculation methods in their land surface schemes. The atmospheric forcing errors are mainly attributable to high shortwave radiation likely due to the underestimation of clouds, but also precipitation errors, especially in water-limited regions.
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Melling, Laura, Amber Leeson, Malcolm McMillan, Jennifer Maddalena, Jade Bowling, Emily Glen, Louise Sandberg Sørensen, Mai Winstrup et Rasmus Lørup Arildsen. « Evaluation of satellite methods for estimating supraglacial lake depth in southwest Greenland ». Cryosphere 18, no 2 (8 février 2024) : 543–58. http://dx.doi.org/10.5194/tc-18-543-2024.
Texte intégralRésumé :
Abstract. Supraglacial lakes form on the Greenland ice sheet in the melt season (May to October) when meltwater collects in surface depressions on the ice. Supraglacial lakes can act as a control on ice dynamics since, given a large enough volume of water and a favourable stress regime, hydrofracture of the lake can occur, which enables water transfer from the ice surface to the bedrock, where it can lubricate the base. The depth (and thus volume) of these lakes is typically estimated by applying a radiative transfer equation (RTE) to optical satellite imagery. This method can be used at scale across entire ice sheets but is poorly validated due to a paucity of in situ depth data. Here we intercompare supraglacial lake depth detection by means of ArcticDEM digital elevation models, ICESat-2 photon refraction, and the RTE applied to Sentinel-2 images across five lakes in southwest Greenland. We found good agreement between the ArcticDEM and ICESat-2 approaches (Pearson's r=0.98) but found that the RTE overestimates lake depth by up to 153 % using the green band (543–578 nm) and underestimates lake depth by up to 63 % using the red band (650–680 nm). Parametric uncertainty in the RTE estimates is substantial and is dominated by uncertainty in estimates of reflectance at the lakebed, which are derived empirically. Uncertainty in lake depth estimates translates into a poor understanding of total lake volume, which could mean that hydrofracture likelihood is poorly constrained, in turn affecting ice velocity predictions. Further laboratory studies to constrain spectral radiance loss in the water column and investigation of the potential effects of cryoconite on lakebed reflectance could improve the RTE in its current format. However, we also suggest that future work should explore multi-sensor approaches to deriving lake depth from optical satellite imagery, which may improve depth estimates and will certainly result in better-constrained uncertainties.
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Liao, Jin, Glenn M. Wolfe, Alexander E. Kotsakis, Julie M. Nicely, Jason M. St. Clair, Thomas F. Hanisco, Gonzalo González Abad et al. « Validation of formaldehyde products from three satellite retrievals (OMI SAO, OMPS-NPP SAO, and OMI BIRA) in the marine atmosphere with four seasons of Atmospheric Tomography Mission (ATom) aircraft observations ». Atmospheric Measurement Techniques 18, no 1 (3 janvier 2025) : 1–16. https://doi.org/10.5194/amt-18-1-2025.
Texte intégralRésumé :
Abstract. Formaldehyde (HCHO) in the atmosphere is an intermediate product from the oxidation of methane and non-methane volatile organic compounds. In remote marine regions, HCHO variability is closely related to atmospheric oxidation capacity, and modeled HCHO in these regions is usually added as a global satellite HCHO background. Thus, it is important to understand and validate the levels of satellite HCHO over the remote oceans. Here we intercompare three satellite retrievals of total HCHO columns from the Ozone Monitoring Instrument Smithsonian Astrophysical Observatory (OMI SAO (v004)) algorithm, Ozone Mapping and Profiler Suite on Suomi National Polar-orbiting Partnership Smithsonian Astrophysical Observatory (OMPS-NPP SAO) algorithm, and Ozone Monitoring Instrument Belgian Institute for Space Aeronomy (OMI BIRA) algorithm and validate them against in situ observations from the NASA Atmospheric Tomography Mission (ATom) mission. All retrievals are correlated with ATom-integrated columns over remote oceans, with OMI SAO (v004) showing the best agreement. This is also reflected in the mean bias (MB) for OMI SAO (−0.73 ± 0.87) × 1015 molec. cm−2, OMPS SAO (−0.76 ± 0.88) × 1015 molec. cm−2, and OMI BIRA (−1.40 ± 1.11) × 1015 molec. cm−2. We recommend the OMI-SAO (v004) retrieval for remote-ocean atmosphere studies. Three satellite HCHO retrievals and in situ ATom columns all generally captured the spatial and seasonal distributions of HCHO in the remote-ocean atmosphere. Retrieval bias varies by latitude and season, but a persistent low bias is found in all products at high latitudes, and the general low bias is most severe for the OMI BIRA product. Examination of retrieval components reveals that slant column corrections have a larger impact on the retrievals over remote marine regions, while AMFs play a smaller role. This study informs us that the potential latitude-dependent biases in the retrievals require further investigation for improvement and should be considered when using marine HCHO satellite data, and vertical profiles from in situ instruments are crucial for validating satellite retrievals.
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Diallo, Mohamadou, Manfred Ern et Felix Ploeger. « The advective Brewer–Dobson circulation in the ERA5 reanalysis : climatology, variability, and trends ». Atmospheric Chemistry and Physics 21, no 10 (18 mai 2021) : 7515–44. http://dx.doi.org/10.5194/acp-21-7515-2021.
Texte intégralRésumé :
Abstract. The stratospheric Brewer–Dobson circulation (BDC) is an important element of climate as it determines the transport and distributions of key radiatively active atmospheric trace gases, which affect the Earth's radiation budget and surface climate. Here, we evaluate the interannual variability, climatology, and trends of the BDC in the ERA5 reanalysis and intercompare them with its predecessor, the ERA-Interim reanalysis, for the 1979–2018 period. We also assess the modulation of the circulation by the Quasi-Biennial Oscillation (QBO) and the El Niño–Southern Oscillation (ENSO), as well as the forcings of the circulation by the planetary and gravity wave drag. The comparison of ERA5 and ERA-Interim reanalyses shows a very good agreement in the morphology of the BDC and in its structural modulations by the natural variability related to QBO and ENSO. Despite the good agreement in the spatial structure, there are substantial and significant differences in the strength of the BDC and natural variability impacts on the BDC between the two reanalyses, particularly in the upper troposphere and lower stratosphere (UTLS) and in the upper stratosphere. Throughout most regions of the stratosphere, the variability and trends of the advective BDC are stronger in the ERA5 reanalysis due to stronger planetary and gravity wave forcings, except in the UTLS below 20 km where the tropical upwelling is up to 40 % weaker mainly due to a significantly weaker gravity wave forcing at the equatorial-ward upper flank of the subtropical jet. In the extratropics, the large-scale downwelling is stronger in ERA5 than in ERA-Interim that is linked to significant differences in planetary and gravity wave forcings in the upper stratosphere. Analysis of the BDC trend shows a global insignificant acceleration of the annual mean residual circulation with an acceleration rate of about 1.5 % decade−1 at 70 hPa due to the long-term intensification in gravity and planetary wave breaking, consistent with observed and modelled BDC changes. Our findings suggest that the advective BDC from the kinematic ERA5 reanalysis is well suited for climate model validation in the UTLS and mid-stratosphere when using the standard formula of zonally averaged zonal momentum equation. The reported differences between the two reanalyses may also affect the nudged climate model simulations. Therefore, additional studies are needed to investigate whether or not nudging climate models toward ERA5 reanalysis will reproduce the upwelling trends from free-running simulations and from ERA5. Finally, further studies are also needed to better understand the impact of the new non-orographic gravity wave parameterization scheme, higher model top, and the representation of the sponge layer in ERA5 on the differences in the upper stratosphere and polar regions.
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Tack, Frederik, Alexis Merlaud, Andreas C. Meier, Tim Vlemmix, Thomas Ruhtz, Marian-Daniel Iordache, Xinrui Ge et al. « Intercomparison of four airborne imaging DOAS systems for tropospheric NO<sub>2</sub> ; mapping – the AROMAPEX campaign ». Atmospheric Measurement Techniques 12, no 1 (11 janvier 2019) : 211–36. http://dx.doi.org/10.5194/amt-12-211-2019.
Texte intégralRésumé :
Abstract. We present an intercomparison study of four airborne imaging DOAS instruments, dedicated to the retrieval and high-resolution mapping of tropospheric nitrogen dioxide (NO2) vertical column densities (VCDs). The AROMAPEX campaign took place in Berlin, Germany, in April 2016 with the primary objective to test and intercompare the performance of experimental airborne imagers. The imaging DOAS instruments were operated simultaneously from two manned aircraft, performing synchronised flights: APEX (VITO–BIRA-IASB) was operated from DLR's DO-228 D-CFFU aircraft at 6.2 km in altitude, while AirMAP (IUP-Bremen), SWING (BIRA-IASB), and SBI (TNO–TU Delft–KNMI) were operated from the FUB Cessna 207T D-EAFU at 3.1 km. Two synchronised flights took place on 21 April 2016. NO2 slant columns were retrieved by applying differential optical absorption spectroscopy (DOAS) in the visible wavelength region and converted to VCDs by the computation of appropriate air mass factors (AMFs). Finally, the NO2 VCDs were georeferenced and mapped at high spatial resolution. For the sake of harmonising the different data sets, efforts were made to agree on a common set of parameter settings, AMF look-up table, and gridding algorithm. The NO2 horizontal distribution, observed by the different DOAS imagers, shows very similar spatial patterns. The NO2 field is dominated by two large plumes related to industrial compounds, crossing the city from west to east. The major highways A100 and A113 are also identified as line sources of NO2. Retrieved NO2 VCDs range between 1×1015 molec cm−2 upwind of the city and 20×1015 molec cm−2 in the dominant plume, with a mean of 7.3±1.8×1015 molec cm−2 for the morning flight and between 1 and 23×1015 molec cm−2 with a mean of 6.0±1.4×1015 molec cm−2 for the afternoon flight. The mean NO2 VCD retrieval errors are in the range of 22 % to 36 % for all sensors. The four data sets are in good agreement with Pearson correlation coefficients better than 0.9, while the linear regression analyses show slopes close to unity and generally small intercepts.
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Sazib, Nazmus, Iliana Mladenova et John Bolten. « Leveraging the Google Earth Engine for Drought Assessment Using Global Soil Moisture Data ». Remote Sensing 10, no 8 (11 août 2018) : 1265. http://dx.doi.org/10.3390/rs10081265.
Texte intégralRésumé :
Soil moisture is considered to be a key variable to assess crop and drought conditions. However, readily available soil moisture datasets developed for monitoring agricultural drought conditions are uncommon. The aim of this work is to examine two global soil moisture datasets and a set of soil moisture web-based processing tools developed to demonstrate the value of the soil moisture data for drought monitoring and crop forecasting using the Google Earth Engine (GEE). The two global soil moisture datasets discussed in the paper are generated by integrating the Soil Moisture Ocean Salinity (SMOS) and Soil Moisture Active Passive (SMAP) missions’ satellite-derived observations into a modified two-layer Palmer model using a one-dimensional (1D) ensemble Kalman filter (EnKF) data assimilation approach. The web-based tools are designed to explore soil moisture variability as a function of land cover change and to easily estimate drought characteristics such as drought duration and intensity using soil moisture anomalies and to intercompare them against alternative drought indicators. To demonstrate the utility of these tools for agricultural drought monitoring, the soil moisture products and vegetation- and precipitation-based products were assessed over drought-prone regions in South Africa and Ethiopia. Overall, the 3-month scale Standardized Precipitation Index (SPI) and Normalized Difference Vegetation Index (NDVI) showed higher agreement with the root zone soil moisture anomalies. Soil moisture anomalies exhibited lower drought duration, but higher intensity compared with SPIs. Inclusion of the global soil moisture data into the GEE data catalog and the development of the web-based tools described in the paper enable a vast diversity of users to quickly and easily assess the impact of drought and improve planning related to drought risk assessment and early warning. The GEE also improves the accessibility and usability of the earth observation data and related tools by making them available to a wide range of researchers and the public. In particular, the cloud-based nature of the GEE is useful for providing access to the soil moisture data and scripts to users in developing countries that lack adequate observational soil moisture data or the necessary computational resources required to develop them.
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Opacka, Beata, Jean-François Müller, Trissevgeni Stavrakou, Maite Bauwens, Katerina Sindelarova, Jana Markova et Alex B. Guenther. « Global and regional impacts of land cover changes on isoprene emissions derived from spaceborne data and the MEGAN model ». Atmospheric Chemistry and Physics 21, no 11 (3 juin 2021) : 8413–36. http://dx.doi.org/10.5194/acp-21-8413-2021.
Texte intégralRésumé :
Abstract. Among the biogenic volatile organic compounds (BVOCs) emitted by plant foliage, isoprene is by far the most important in terms of both global emission and atmospheric impact. It is highly reactive in the air, and its degradation favours the generation of ozone (in the presence of NOx) and secondary organic aerosols. A critical aspect of BVOC emission modelling is the representation of land use and land cover (LULC). The current emission inventories are usually based on land cover maps that are either modelled and dynamic or satellite-based and static. In this study, we use the state-of-the-art Model of Emissions of Gases and Aerosols from Nature (MEGAN) model coupled with the canopy model MOHYCAN (Model for Hydrocarbon emissions by the CANopy) to generate and evaluate emission inventories relying on satellite-based LULC maps at annual time steps. To this purpose, we first intercompare the distribution and evolution (2001–2016) of tree coverage from three global satellite-based datasets, MODerate resolution Imaging Spectroradiometer (MODIS), ESA Climate Change Initiative Land Cover (ESA CCI-LC), and the Global Forest Watch (GFW), and from national inventories. Substantial differences are found between the datasets; e.g. the global areal coverage of trees ranges from 30 to 50×106 km2, with trends spanning from −0.26 to +0.03 % yr−1 between 2001 and 2016. At the national level, the increasing trends in forest cover reported by some national inventories (in particular for the US) are contradicted by all remotely sensed datasets. To a great extent, these discrepancies stem from the plurality of definitions of forest used. According to some local censuses, clear cut areas and seedling or young trees are classified as forest, while satellite-based mappings of trees rely on a minimum height. Three inventories of isoprene emissions are generated, differing only in their LULC datasets used as input: (i) the static distribution of the stand-alone version of MEGAN, (ii) the time-dependent MODIS land cover dataset, and (iii) the MODIS dataset modified to match the tree cover distribution from the GFW database. The mean annual isoprene emissions (350–520 Tg yr−1) span a wide range due to differences in tree distributions, especially in isoprene-rich regions. The impact of LULC changes is a mitigating effect ranging from 0.04 to 0.33 % yr−1 on the positive trends (0.94 % yr−1) mainly driven by temperature and solar radiation. This study highlights the uncertainty in spatial distributions of and temporal variability in isoprene associated with remotely sensed LULC datasets. The interannual variability in the emissions is evaluated against spaceborne observations of formaldehyde (HCHO), a major isoprene oxidation product, through simulations using the global chemistry transport model (CTM) IMAGESv2. A high correlation (R > 0.8) is found between the observed and simulated interannual variability in HCHO columns in most forested regions. The implementation of LULC change has little impact on this correlation due to the dominance of meteorology as a driver of short-term interannual variability. Nevertheless, the simulation accounting for the large tree cover declines of the GFW database over several regions, notably Indonesia and Mato Grosso in Brazil, provides the best agreement with the HCHO column trends observed by the Ozone Monitoring Instrument (OMI). Overall, our study indicates that the continuous tree cover fields at fine resolution provided by the GFW database are our preferred choice for constraining LULC (in combination with discrete LULC maps such as those of MODIS) in biogenic isoprene emission models.
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Rzymkowska, S. « Ruling Regarding Default on Intercompany Loans : The Reason for an Income Adjustment ». International Transfer Pricing Journal 19, no 4 (26 juin 2012). http://dx.doi.org/10.59403/14x1hq5.
Texte intégralRésumé :
The author considers a ruling by the Lower Administrative Court in Warsaw regarding a disputed tax assessment in connection with intercompany loans which had not been settled in accordance with the relevant internal loan agreements. The case is still subject to an appeal procedure, so the conclusions of the case may change due to Supreme Administrative Court’s judgment.
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Scandone, F. S., et B. Leoni. « Reinsurance Intra-Group Agreements – The Key Role of RE-EVA in Supporting the Arm’s Length Principle ». International Transfer Pricing Journal 29, no 6 (4 octobre 2022). http://dx.doi.org/10.59403/1vq8twr.
Texte intégralRésumé :
In an economic context in which risk management plays an important role for the economic players, it is increasingly common to come across reinsurance transactions. In this context, multinationals often make use of reinsurance agreements, generating significant transnational flows with the related consequences also in terms of transfer prices. Despite the efforts made by the OECD with the publication of the new chapter X of the OECD Transfer Pricing Guidelines and with the clarifications provided on risk analysis, the common transfer pricing rules are not immediately applicable to reinsurance operations, also due to the complexity of the agreements and the difficulty of applying the existing TP methods to them. Therefore, this article, having analysed the main transfer pricing risks associated with intercompany reinsurance transactions, intends to provide possible new tools to verify the compliance with the arm’s length principle of reinsurance agreements, such as the combined ratio, the capital release, actuarial analysis and the RE-EVA.
36
Sutton, P. « HM Revenue & ; Customs Takes a Tougher Stance with New TP Guidelines ». International Transfer Pricing Journal 32, no 1 (15 novembre 2024). http://dx.doi.org/10.59403/ty28zk.
Texte intégralRésumé :
In September, HM Revenue & Customs in the United Kingdom published new TP guidelines. This latest guidance suggests that HMRC is moving in lockstep with the United States and other OECD tax administrations and is looking to shore up the UK tax base. However, rather than attempting to prescribe the pricing of specific transactions, the new guidance explains the UK tax authority’s expectations as regards transfer pricing documentation and – more significantly – what processes MNEs should implement in order to ensure that the corporation tax returns and transfer pricing documents that they file reflect arm’s length outcomes. This article highlights key points from the new HMRC guidance and draws out key lessons for MNEs and their advisers as regards the management of intercompany agreements for transfer pricing compliance.
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Gódor, M. « Interpretative Statement Issued by the Tax Authorities on the Application of the Arm’s Length Principle to a Loan Guarantee Agreement ». International Transfer Pricing Journal 20, no 5 (15 août 2013). http://dx.doi.org/10.59403/1yy8rhs.
Texte intégralRésumé :
The author considers recent guidance from the Hungarian tax authorities on the application of transfer pricing adjustments to intercompany transactions subsequent to a change in status as related parties.
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Damsma, B., et K. Łukosz. « No Deduction Allowed for Loss under Cross-Guarantee ». International Transfer Pricing Journal 20, no 4 (4 juillet 2013). http://dx.doi.org/10.59403/1ww511r.
Texte intégralRésumé :
The authors consider a recent ruling of the Dutch Supreme Court regarding the deductibility of a loss suffered following default under a cross-guarantee agreement. This ruling has potentially far-reaching implications for intercompany guarantee arrangements.
39
Bakker, A. J. « Transfer Pricing and Intra-Group Financing : Low-Hanging Fruit ? » Finance and Capital Markets (formerly Derivatives & ; Financial Instruments) 15, no 2 (19 février 2013). http://dx.doi.org/10.59403/3xfsbre.
Texte intégralRésumé :
The author provides an overview of the transfer pricing issues related to intra-group financing. Topics considered include the reasons for increased controversy in this field, what taxpayers should bear in mind when intercompany loans are in place and a new loan agreement with related parties will be concluded, and the potential issues with guarantees and cash pooling. Some recommendations are also offered.
40
jupp, A. « Transfer Pricing End-of-Year Adjustments in the United Kingdom ». International Transfer Pricing Journal 31, no 7 (29 octobre 2024). http://dx.doi.org/10.59403/2wz6zfq.
Texte intégralRésumé :
The United Kingdom’s transfer pricing legislation, contained in Part 4 of the Taxation (International and Other Provisions) Act 2010, mandates that profits and losses for tax purposes be calculated as if arm’s length provisions were made between related parties, aligning with OECD guidance. This legislation generally only allows adjustments that increase UK profits (a feature often referred to as the “one-way street”), with exceptions only for mutual agreement procedure outcomes or compensating adjustments between UK resident entities, resulting in careful consideration of intercompany arrangements being required to minimize year-end adjustments.
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Jupp, A., K. Heggs et A. Rigby. « Transfer Pricing End-of-Year Adjustments in the United Kingdom ». International Transfer Pricing Journal 31, no 7 (18 novembre 2024). http://dx.doi.org/10.59403/20xjafx.
Texte intégralRésumé :
The United Kingdom’s transfer pricing legislation, contained in Part 4 of the Taxation (International and Other Provisions) Act 2010, mandates that profits and losses for tax purposes be calculated as if arm’s length provisions were made between related parties, aligning with OECD guidance. This legislation generally only allows adjustments that increase UK profits (a feature often referred to as the “one-way street”), with exceptions only for mutual agreement procedure outcomes or compensating adjustments between UK resident entities, resulting in careful consideration of intercompany arrangements being required to minimize year-end adjustments.This article is part of a special issue of the International Transfer Pricing Journal on transfer pricing end-of-year adjustments. The other articles include the General Report and contributions on Belgium, France, Germany, Ireland, Italy, Korea,the Netherlands, Spain and the United States.