Journal articles on the topic 'Nautical Astronomy'

The last three years have been marked by changes, highlights and progress. Organizationally, commission 7 has joined Division I and plans proceed for commissions 8 and 24 to merge in 2000. They have had a common vice president during this triennium. Sadly, the Royal Greenwich Observatory was closed after over 200 years, but Her Majesty’s Nautical Almanac Office has continued at Rutherford Appleton Laboratory. In St Petersburg, Russia, the Institute of Theoretical Astronomy was abolished, with some of the personnel relocated to the Institute of Applied Astronomy and Pulkova Observatory. In Paris, France, the Bureau des Longitudes was reorganized as the Institute of Celestial Mechanics-Bureau des Longitudes as part of the Paris Observatory.

Resumo Descreve-se a evolução do Observatório Astronómico da Universidade de Coimbra de 1930 a 1970, destacando- se o exercício das funções de diretor por Manuel dos Reis (1900-1992), de 1934 a 1970. Fonte primordial é o espólio documental de Manuel dos Reis à guarda do Arquivo da Universidade de Coimbra, que inclui programas, lições, problemas, exames, estudos e notas, e outros manuscritos sobre História da Astronomia, Astronomia (Geral, Mecânica, Esférica e Geodésica), Astronomia Medieval, e Astronomia Náutica dos Descobrimentos. Engloba ainda listas bibliográficas, rascunhos das comunicações e discursos sobre Astronomia Náutica proferidos na Academia das Ciências de Lisboa. Apresenta-se, em particular, um documento datilografado, inédito, provavelmente da década de 30, com o título “Reorganização do ensino da Astronomia e da investigação astronómica”, onde Reis, após descrever brevemente a história da Astronomia, refere a Astrofísica como o “novo capítulo da Astronomia”, e reflete sobre o ensino e investigação da Astronomia, e sobre o funcionamento dos Observatórios Astronómicos de Coimbra e de Lisboa (Tapada da Ajuda), e do Observatório Meteorológico do Porto (Serra do Pilar).Palavras-chave: História da Astronomia em Portugal; Astrofísica, Observatório Astronómico da Universidade de Coimbra. Abstract The evolution of the Astronomical Observatory of the University of Coimbra from 1930 to 1970 is described, highlighting Manuel dos Reis (1900-1992) role as director from 1934 to 1970. Main source is the collection of Manuel dos Reis documentation in the Archive of the University of Coimbra, which includes programs, lessons, problems, exams, studies and notes and other manuscripts on the History of Astronomy, Astronomy (General, Mechanical, Spherical and Geodesical), Medieval Astronomy, Nautical Astronomy of the Portuguese Discoveries. It also includes lists of bibliographical references, minutes of communications and speeches on Nautical Astronomy delivered at the Academy of Sciences of Lisbon. A typewritten, unpublished document, with the title "Reorganization of the teaching of astronomy and astronomical investigation”, probabbly from the 1930s, is presented. Reis, after a brief description of the history of Astronomy, describes Astrophysics as the "new chapter of Astronomy", reflects on the teaching and research on Astronomy, and on the operation of the Astronomical Observatories of Coimbra and Lisbon (Tapada da Ajuda), and the Meteorological Observatory of OPorto (Serra do Pilar). Keywords: History of Astronomy in Portugal; Astrophysics; Astronomical Observatory of the University of Coimbra.

In this technological age, when anartistof nautical astronomy is fast becoming a figure of history, there is a tendency to regard astro-navigation as something that went out with the dodo. It would be as well to remember, therefore, that despite the widespread use of radio navaids from the early years of World War II, astronomical navigation remained the only world-wide fixing system until the launch of the Transit navigation satellites during the 1960s. The truth is that the first half of the present century saw enormous advances in both its methods and practice and the fact that it is still in wide use can be judged by the large number of Nautical Almanacs sold annually.

The universe of marine navigators and surveyors is basically a geocentric one. All calculations necessary for reducing celestial observations to obtain directional or positional information can be carried out within the pre- Copernican two sphere hypothesis. Some mature students on the degree courses have practical experience of navigation at sea but are not used to more abstract ways of thinking. However, most courses in navigation require students to understand the many corrections that have to be applied in astro-navigation. The planetarium can be used to illustrate the basic concepts of the two sphere hypothesis, although other methods are needed to understand the nautical almanac and the principles used in its calculation.

Of the great oceans of the world, the Atlantic, because of its violence, was the last to be mastered by man. The task in its entirety had to wait for the Portuguese sailors of the Renaissance. Isidore of Seville (c. 570–636), a Christian writer of the late Roman Empire, had written of the Atlantic that it was ‘incommensurable and uncrossable’. Although Pliny (a.d. 23–79) refers vaguely to the Canary Islands, all knowledge of them disappears in the Middle Ages until a Portuguese expedition under the command of the Italian Lanzarotto Malocello ‘re- discovered’ them in 1336. Italian charts of the XIVth century begin progressively to show the Canaries, Madeira, Porto Santo and the Azores, but all aligned along a N/S axis without any appreciation of the relative distances between them or how far they lay from the European shore. The first written evidence of the Portuguese ‘discovery’ of the islands of Madeira and Porto Santo appears in 1419–20 and of the Azores in 1427, about the same time as they began to be colonised under the aegis of Prince Henry of Portugal, called the ‘Navigator’. The difficulties of returning to them on regular voyages was to motivate the Portuguese to develop methods of measurement using the Pole Star as a navigational aid and this led, not only to a greater accuracy in placing the islands on the charts, but also to a greater precision in the charting of the west African coastline which they were progressively exploring during the second half of the XVth century.Claims that Portuguese nautical astronomy originated in Aragon and was transmitted from there to Portugal or was introduced into Portugal from Germany by Regiomontanus and Martin Behaim have long ago been shown to be baseless.

A escrita da história da astronomia foi conduzida por alguns pontos chaves: a relação deste saber com as viagens de expansão e o aprimoramento da náutica, a diferenciação da astrologia e o questionamento do lugar da ciência e da superstição para o estudo do céu, bem como a construção das estruturas deste saber pelos escritos que desdobraram o assunto. Todas estas tópicas foram desenvolvidas em maior ou menor grau nos estudos historiográficos das décadas passadas que trataram da ciência do céu. Assim, este texto trata da astronomia dos séculos XV e XVI como objeto de estudos historiográficos que privilegiaram determinados aspectos deste saber, confluindo muitas vezes com a recusa – que já estava explícita nos escritos quatrocentistas – daquilo que veio se afirmar no futuro como algo totalmente desvinculado da astronomia – a astrologia.*The writing of the history of astronomy was conducted by a few key points: the relation of this knowledge to voyages of expansion and improvement of nautical, the differentiation of astrology and the questioning of the place of science and superstition for the study of the sky, as well as the construction of structures of this knowledge by the writings that unfolded the subject. All these topics were developed to a greater or lesser extent in the historiographical studies of the past decades about the science of the sky. Thus, this text deals with the astronomy of the fifteenth and sixteenth centuries as an object of historiographical studies that privileged certain aspects of this lore, often converging with the refusal - which was already explicit in the writings of the fourteenth century - of what came to be affirmed in the future as something totally unrelated to astronomy - astrology.

It is believed that Vasco da Gama carried nautical tables on his first voyage to the Indies, 1497–1499, that had especially been produced for the years 1497–1500 by Abraham Zacut, then Royal Astronomer in the service of the Portuguese court. Maritime history writers have suggested two manuscripts as surviving copies of these da Gama tables. One of them is a set of declination tables in the 1519 edition of Suma de Geographia by Martín Fernández de Enciso. Analysis of all available data shows that these tables are indeed good candidates, though their production from the 1505–1508 astronomical tables of Regiomontanus and of Stöffler and Pflaum would be about equally likely. The other candidate is a set of solar ecliptic longitudes, found in the Livro de Marinharia, attributed to André Pires. It is shown that with certainty these have been taken from 1505 to 1508 of Regiomontanus/Stöffler-Pflaum and therefore cannot have served da Gama on his first voyage.

Fajr in syar’i concept is divided into two; Fajr Kazib and Fajar Shadiq. The Fajr Kazib is time to having breakfast before doing fasting and have no salah Subuh. The second is fajr Shadiq. It is time to have no having meal (because it is fasting time) and time to do salah Subuh. Fajr Kazib arises at the early morning whose the light is not bright, but it is longer to the top of East to West vertically. Then the sky comes dark like wolf tail. While Fajr Shadiq arises at the early morning whose light is bright spreading in East horizontally. It arises just before sunrise. Time between Fajr Shadiq and the sunrise is the time for salah Subuh.
 In Astronomy, the word Fajr means Morning Twilight. Twilight in Astronomy is divided into three; astronomical twilight, nautical twilight and civil twilight. First, astronomical twilight is as the end of night. That is when starlight is not bright because of sunrise. The sun position is level 18 below the horizon. At that time, there ios still dark because of the sun going to rise ( an hour and 12 minutes later the sun rises). The second is nautical twilight. It looks so bright is East horizon for the sailors who are going to land. The sun position is level 12 below the horizon (48 minutes later the sun rises). The third is civil twilight. It is Fajr whose the light is so bright in which the position is level 6 below the horizon. At that time, the sunlight is so really bright, and many people do their morning activities. And then 24 minutes later the sun rises.

This paper explores Aristotle's remarks in Posterior Analytics on certain special disciplines that are subordinate to pure mathematical sciences. Optics, harmonics and mechanics prove their own contents by means of premises belonging to arithmetic or geometry. Even though subaltern sciences are exceptions to the prohibition on kind crossing, the premises to their demonstrations are legitimately appropriate to the relative conclusions. In order to delineate the demonstrative structure of subordinate sciences, Aristotle introduces the distinction between knowledge of a fact and knowledge of the reason for it. In his view, these two different levels of knowledge, characterizing respectively empirical and theoretical approaches, are closely related. Nautical astronomy, for instance, deals with the observation and recording of the astral motions, which are made intelligible by mathematical astronomy. The Aristotelian ideal of an explanatory connection between appearances and mathematical principles seems to be the main aspect in the treatment of subordinate sciences in Posterior Analytics.

AbstractNevil Maskelyne, the Cambridge-trained mathematician and later Astronomer Royal, was appointed by the Royal Society to observe the 1761 transit of Venus from the Atlantic island of St Helena, assisted by the mathematical practitioner Robert Waddington. Both had experience of measurement and computation within astronomy and they decided to put their outward and return voyages to a further use by trying out the method of finding longitude at sea by lunar distances. The manuscript and printed records they generated in this activity are complemented by the traditional logs and journals kept by the ships’ officers. Together these records show how the mathematicians came to engage with the navigational practices that were already part of shipboard routine and how their experience affected the development of the methods that Maskelyne and Waddington would separately promote on their return. The expedition to St Helena, in particular the part played by Maskelyne, has long been regarded as pivotal to the introduction of the lunar method to British seamen and to the establishment of the Nautical Almanac. This study enriches our understanding of the episode by pointing to the significant role played by the established navigational competence among officers of the East India Company.

Analysis of fifteenth- and sixteenth-century solar tables which have been used in navigation, and of declination tables derived from them, reveals that much of the accepted history needs revision. In particular, the celebrated astronomical tables of Abraham Zacut contain systematic and accidental errors by which later tables may be identified as derived from them. The tables of Pedro Nunez and Martín Cortes are not their own, but have been copied from those of Philipp Imsser, which are usually, but incorrectly, attributed to his predecessor Johannes Stöffler. William Bourne used an incorrect conversion table to calculate his declinations and had to manipulate his data to hide it. Pedro de Medina’s Dutch translation by Marten Everaert has declination tables that fit neither the Alfonsine nor the Copernican scheme and are inconsistent within themselves. Also, the declination tables of Lucas Jansz. Waghenaer need amendment and those of Willem Jansz Blaeu are older than he suggests himself. The absolute accuracy of declination tables is assessed in retrospect by comparison with modern celestial mechanics programmes.

Transit of Venus over the solar disc is an extremely rare event. The phenomenon occurred last time on June 8, 2004 when the entire event was visible from all parts of India. Another Transit of Venus is going to occur on June 6, 2012, though the entire event will not be visible from India. The Positional Astronomy Centre publishes data on Transit of Mercury and Venus in its annual publication ‘The Indian Astronomical Ephemeris’. In this paper an attempt has been made to provide documentation on the methodology for computation of contact timings of the event. Using the methodology, the geocentric contact timings and local contact timings for important places of India for the event of Transit of Venus of June 6, 2012 have been predicted. The result thus obtained for different geocentric phases of the event has been compared with the predicted timings published by The Nautical Almanac Office, United States Naval Observatory and NASA.

This paper distinguishes four perspectives in the process of reception of Copernicanism in colonial Rio de la Plata: (1) the discussion of the systems of the world in the University of Córdoba by the Jesuits until 1767, (2) the treatment of this topic by the Franciscans in Córdoba and in their convent school in Buenos Aires, (3) the teaching by the secular clergy in the Colegio de San Carlos in the same city, and (4) the celebration of Copernicus by the enlightened naval engineer Pedro Cerviño in the Nautical School of the Consulado de Buenos Aires. The examination of these cases on the basis of manuscript sources and colonial printings shows that the reception of Copernican theory was an erratic process rich in incidences.

<p class="Abstract">In astronomy, there are three types of dawn. They are astronomical, nautical, and civil dawn. The sunlight is starting to appear on the east horizon when the Sun altitude is 18<sup>o</sup> below the horizon. Hence, there is a change on the sky brightness. The sky brightness can be affected by the moon phases. The sky brightness level is monitored by Sky Quality Meter (SQM). The SQM was installed upward to the zenith. There are 4 locations of measurement in Yogyakarta. The data has been collected for nine months to obtain the complete moon phases. The beginning of astronomical dawn is time when the sky brightness level is starting to decrease. The moving average algorithm was employed to determine the beginning of astronomical dawn. The time when the astronomical dawn begins is compared with the sun altitude calculation. The sun altitude calculation has been done using accurate times software. The difference of the beginning of astronomical dawn by measurement and calculation are 18.61±6.81 minutes, 19.12±3.28 minutes, 31.12±7.76 minutes, and 27.24±8.04 minutes, on the new moon (0), on the first quarter (0.25), on the full moon (0.5) and on the last quarter (0.75), respectively. The weather condition is also contributing to the results.</p>

Currently, in ocean navigation, one of the backup methods, and often the only one, is the astronomical method of determining the ship’s position. To jointly determine the latitude and longitude of a place from the end of the 19th century to the present day, only one navigation parameter is used - the altitude, although in nautical astronomy other navigation parameters can theoretically be used - altitude difference, sum of altitude, azimuth, azimuth difference, etc. In practice, there is no acceptable method for determining the latitude and longitude of a ship’s position from the measured altitude difference. The existing method of position lines for plotting isolines on a navigation map makes it possible to develop a method acceptable for navigation practice for determining the latitude and longitude of a vessel from the measured altitude difference. In this study, the author justifies the practical possibility of determining the coordinates of a vessel astronomically from the altitude difference, based on separate measurements of the altitude with a navigation sextant. The developed method for determining the coordinates of a ship's location from the measured altitude difference allows us to significantly increase the accuracy of determining the latitude and longitude of the ship's location by reducing the influence of random method errors caused by the geographical coordinates of the ship's location and the position of the Luminary illumination pole on the Earth's surfac e, as well as eliminating the influence of systematic altitude measurement errors. Another advantage of the method is that it is completely autonomous and makes it possible to use the sextant for measurements available on board. Keywords: celestial navigation, position measurement, astronomical ship positioning, altitude difference.

Early in 1967, a few months before the restored Meridian Building of the Old Royal Observatory was opened to the public by Sir Richard Woolley, the Astronomer Royal, I received a visitor in my office then in the Meridian Building — later, I was to move to the west summer house of Flamsteed House. My visitor was Colonel Humphrey Quill, Royal Marines, Master of the Worshipful Company of Clockmakers that same year and author of the hookJohn Harrison, the Man who Found Longitude, which has become a standard work. He brought with him some manuscripts written by the subject of this lecture — Nevil Maskelyne, fifth Astronomer Royal, who lived in Flamsteed House for 46 years from 1765, making most of his important astronomical observations in the very building in which Col. Quill and I were sitting.

Several studies on distance and size estimation have focused on normal and night vision goggles (NVGs), but none of them have been performed during the twilight period. Hence, in this study, distance was estimated for the first time during nautical twilight. According to the findings, the accuracy of distance estimation reduces as visibility decreases and is restricted. When compared with Day Limited Helmet Mounted Display Vision (M = 5.27, SD = .59), Twilight Normal Vision (M = 5.33, SD = .69) and Twilight Helmet Mounted Display Vision (M = 5.20, SD = .61), NVG (M = 4.79, SD = .57) appears to have a lower error rate. In this study, distance was estimated considering objects determined during the helicopter flight by the pilots in different visibility conditions, which are significant in the field of aviation. This work is unique owing to its coverage of helicopter pilots and the estimation during the twilight period. In view of our findings, it may be reasonable to postpone the planned helicopter flights during poor visibility conditions.

RESUMENEn este artículo se trata de analizar los textos de pilotaje utilizados en el siglo xviii y su adecuación a la ciencia del momento. Para ello, abordamos el estado de la ciencia mediante el establecimiento de los hitos que marcaron la evolución de la navegación astronómica científica y, por otra parte, realizamos el análisis comparativo de los textos, para finalmente determinar si estos adoptaron o no los adelantos de la ciencia náutica y en su caso el periodo transcurrido hasta incluirlos en los textos. Palabras clave: ciencia, náutica, astronomía de posición, textos náuticos Topónimos: EspañaPeriodo: siglo xviii ABSTRACTThis article tries to analyze the pilotage texts used in the 18th century and their adaptation to the existing science. To do this, we address the state of science by establishing the milestones that marked the evolution of scientific astronomical navigation; on the other hand, we perform a comparative analysis of the texts. 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The mid-nineteenth century was a highpoint of empire building, and reliable navigation across the oceans was crucial. While the effects of magnetic variation and deviation on compasses were well known by 1800, iron ships brought with them an even bigger challenge. The nautical world divided between ‘applied’ and ‘theoretical’ approaches to addressing the ‘compass problem’. This article focuses on the role of Janet Taylor, who lived and worked in the heart of this community, as a writer, teacher, inventor, chart-seller and compass adjuster, as a follower of the system of compass adjustment advocated by the Astronomer Royal, Professor George Airy. Janet Taylor’s achievements in the compass adjusting field and her interactions with the Astronomer Royal are explored, adding another insight into Mrs Taylor’s distinctive story.

Dalam menjalankan shalat, umat muslim tidak boleh asal-asalan waktunya, karena shalat merupakan ibadah yang telah ditentukan waktu dan caranya (kitaban mauqutan). Dizaman sekarang, kita tidak kesulitan mengetahui waktu shalat, dikarenakan adanya jadwal waktu shalat. Jadwal waktu shalat yang beredar kesemuanya merupakan hasil dari penelitian atas fenomena fajar. Fajar terbagi menjadi 2, yakni Fajar Kadzib dan Fajar Shadiq; Fajar Kadzib ialah fajar yang mempunyai bentuk seperti ekor srigala yang terlihat memanjang keatas, lalu Fajar Shadiq ialah cahaya pagi yang bersinar di ufuk timur saat akan terbitnya Matahari. 
 Secara astronomi nilai ketinggian fajar ini terbagi menjadi tiga; 1) Fajar Astronomi, 2) Fajar Nautika dan 3) Fajar Sipil. Fajar Astronomi ialah keadaan munculnya hamburan cahaya Matahari oleh atmosfer Bumi, posisi Matahari berada di 18° dibawah ufuk; Fajar Nautika ialah ketampakan ufuk bagi para pelaut, yakni saat Matahari berada di 12° dibawah ufuk; dan Fajar Sipil ialah ketampakan benda-benda di sekitar kita secara jelas, yakni saat Matahari berada di 6° dibawah ufuk. 
 Di Indonesia, fajar sebagai penanda awal waktu shubuh menggunakan kriteria 20° dibawah ufuk (1 jam lebih 20 menit) sebelum Matahari terbit, ini dipilih oleh BHR Kemenag RI sebagai awal munculnya fajar.

Israel Lyons grew up among the academic luminaries of mid–eighteenth–century Cambridge, but his humble Jewish origins prevented him from becoming a member of the university. Nevertheless, his precocious mathematical genius and his botanical enthusiasm led to a publication on fluxions at the age of 19, and a survey of Cambridge flora a few years later. His botanical skills made him Oxford's choice to lecture on the principles of botany to the young Joseph Banks and 60 of his fellow students, and his mathematical abilities made him the Astronomer Royal's choice for one of the first two computers for the Nautical Almanac. Eventually chosen, through Banks's patronage, as the astronomer for the 1773 voyage toward the North Pole, led by the Hon. Constantine Phipps, F.R.S., his career ended with a tragically early death at the age of 36, but his contemporary fame had been considerable and his achievements were remarkable in the light of his background.

Data of solar coordinate such as longitude and latitude of the ecliptic, declination, and right ascension are the data that are often involved in astronomical reckoning and practical islamic astronomy. These data are often found in ephemeris tables such as the ephemeris of Hisab Rukyat by Ministry of Religious Affairs of the Republic of Indonesia, Nautica Almanac and others. One of the algorithms used in the preparation of ephemeris data tables is the Jean Meeus Higher Accuracy algorithm. Calculation of ephemeris data of solar coordinates using these algorithms starts with counting Julian Day (JD) and Julian Day Ephemeris (JDE). By using advanced algorithms based on VSOP87 theory, we can then calculate the longitude and latitude of the solar ecliptic, the distance of the earth to the Sun, the true obliquity (angle between the celestial equator and the ecliptic), the right ascension and declination, the equation of time and the Sun's semi diameter. The calculation of the solar coordinate in this paper is for June 7, 2017 at 19.00 WIB or 12.00 GMT. The results will then be compared with the data of solar coordinate in Ephemeris Hisab Rukyat 2017 at the same time.

AbstractWe study to what extent the Milky Way was used as an orientation tool at the beginning of the Islamic period covering the 8th to the 15th century, with a focus on the first half of that era. We compare the texts of three authors from three different periods and give detailed comments on their astronomical and traditional content. The text of al-Marzūqī summarises the information on the Milky Way put forward by the astronomer and geographer ʾAbū Ḥanīfa al-Dīnawarī. The text makes it clear that in some areas the Milky Way could be used as a geographical guide to determine the approximate direction toward a region on Earth or the direction of prayer. In the 15th century, the famous navigator Aḥmad b. Māǧid describes the Milky Way in his nautical instructions. He frequently demonstrates that the Milky Way serves as a guidance aid to find constellations and stars that are useful for precise navigation on land and at sea. On the other hand, Ibn Qutayba quotes in his description of the Milky Way a saying from the famous Bedouin poet Ḏū al-Rumma, which is also mentioned by al-Marzūqī. In this saying the Milky Way is used to indicate the hot summer times in which travelling the desert was particularly difficult. Hence, the Milky Way was useful for orientation in space and time and was used for agricultural and navigational purposes.

Fajr in syar’i concept is divided into two; Fajr Kazib and Fajar Shadiq. The Fajr Kazib is time to having breakfast before doing fasting and have no salah Subuh. The second is fajr Shadiq. It is time to have no having meal (because it is fasting time) and time to do salah Subuh. Fajr Kazib arises at the early morning whose the light is not bright, but it is longer to the top of East to West vertically. Then the sky comes dark like wolf tail. While Fajr Shadiq arises at the early morning whose light is bright spreading in East horizontally. It arises just before sunrise. Time between Fajr Shadiq and the sunrise is the time for salah Subuh. In Astronomy, the word Fajr means Morning Twilight. Twilight in Astronomy is divided into three; astronomical twilight, nautical twilight and civil twilight. First, astronomical twilight is as the end of night. That is when starlight is not bright because of sunrise. The sun position is level 18 below the horizon. At that time, there ios still dark because of the sun going to rise ( an hour and 12 minutes later the sun rises). The second is nautical twilight. It looks so bright is East horizon for the sailors who are going to land. The sun position is level 12 below the horizon (48 minutes later the sun rises). The third is civil twilight. It is Fajr whose the light is so bright in which the position is level 6 below the horizon. At that time, the sunlight is so really bright, and many people do their morning activities. And then 24 minutes later the sun rises.
 
 Keywords: dawn, time of dawn (time of Subuh)

Urban air pollution poses a significant challenge, negatively affecting visibility, agriculture, health, and transportation. This research focused on exploring the variability of aerosols using the autoregressive distributed lag (ARDL) approach. To achieve this, monthly aerosol data were obtained from the Aura satellite’s Ozone Monitoring Instrument (OMI) at a distance of 500 nautical miles. In addition, meteorological factors such as Cloud Fraction (CF), Relative Humidity (RH), Tropopause Height (TH), Total Column Water Vapor (TCWV), Water Vapor Mass Mixing Ratio (WVMMR), Surface Skin Temperature (SST), Surface Air Temperature (SAT), and Geopotential Height (GH) were gathered from the atmospheric infrared sounder (AIRS) onboard the AQUA satellite. The MERRA-2 model provided the Total Surface Precipitation (TSP) and Surface Wind Speed (SWS). To assess the short- and long-term relationship between aerosols and meteorological parameters, the ARDL bounds testing technique was applied. The study found evidence of a long-term relationship and co-integration between the variables of interest and aerosols when aerosols were the dependent variable. Particularly, GH, SST, and SWS exhibited both long-term and short-term impacts on aerosol variability. SWS, in particular, was found to have a significant influence on aerosol variability. Conversely, CF, TSP, and WVMMR were found to have no significant impact on aerosol variability. To ensure the stability of the model, the CUSUM test was employed, confirming its stability. Furthermore, the prediction model demonstrated a good fit, bolstering the reliability of our findings.

Ergonomic issues with the design of ships and on-board equipment have been reported to hinder the crew’s performance, increase the chance of erroneous actions and, consequently, lead to negative outcomes of maritime operations. One solution to such issues is following a human-centred approach in system design and evaluation, which helps improve usability. While being widely applied in other sectors such as in designing aviation systems, medical equipment, or consumer electronics, HCD practice is still limited within the maritime field. Acknowledging this issue, the Nautical Institute organised a focus group with the participation of 78 people representing various maritime stakeholders. The participants jointly discussed and proposed solutions to improve HCD adoption in the maritime industry. Proposed solutions were aimed toward promoting awareness of usability and HCD among all stakeholders, increase HCD practices through regulatory documents, provide means to support designers in adopting HCD, and introducing a sector-based strategy to adopt HCD.

AbstractAn environmentally friendly and economical ship operation can be accomplished through many different methods. Most of these approaches focus on technological solutions, e.g. internal engine measures in order to make the engine more eco-friendly, by changing engine control parameters for a better connection between propulsion system and ship, by usage of different fuels or fuel supplements or installation of exhaust gas-treatment systems. For many ships, it is neither efficient nor economically viable to replace or improve existing power generation or propulsion systems in order to improve efficiency or reduce emissions. Some of the internal measures used to reduce NOx-emissions like exhaust gas recirculation even lead to a higher fuel consumption. The vessel itself is still controlled by a crew and they should be kept in the loop to improve efficiency. Therefore optimal operational procedures for handling ships and specifically the outcome of engine manoeuvres is a substantial source for eco-friendly ship operations. The German research project MEmBran (Modelling Emissions and Fuel Consumption during Ship Manoeuvres) addresses especially the basis for optimising ship engine manoeuvres. It focusses on very detailed simulation of the processes of currently existing ship diesel engines, especially in a first step 4-stroke engines in order to implement models in wider comprehensive ship handling simulation software. As part of an existing planning and prediction software that can be used on board, it enables the watch keeping nautical officer and the shipping company to forecast and compare the fuel consumption of the ship for each manoeuvre. In order to reach this goal it is necessary to use fast calculating and stable methods that can be used to forecast the power output of the engine and the fuel consumption. This paper discusses an approach to calculate friction mean effective pressure.