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Atmospheric rivers (ARs) are large and narrow filaments of poleward horizontal water vapor transport. AR carry over 90% of moisture from the tropics to higher latitudes but cover only between 2% and 10% of the earth’s surface. When ARs are forced upwards frequently lead to heavy precipitation. ARs are associated with up to half of the extreme events in the top 2% of the precipitation and wind distribution across most mid-latitude regions. ARs can lead to hydrological hazards, and a better understanding of AR can help in the study, forecasting, and communication of flooding. Because of its direct relationship with horizontal vapor transport, extreme precipitation, and overall AR impacts over land, the AR size is an important characteristic that needs to be better understood. Furthermore, most of the ARs research work focuses on midlatitudes and polar regions. It is not until recently that ARs in tropical latitudes are starting to generate interest within the scientific AR community. We develop and implement five size estimation methods independent of the AR detection algorithms and use them to characterize the size of ARs. We create North American landfalling AR composites using ERA5 reanalysis data in the 1980-2017 period. To study how AR size changes with future climate scenarios, we use data from the Coupled Model Intercomparison Project 5 and 6 (CMIP5/6) to create historical and future AR composites in the 1950-2100 period. We apply our size estimation methods to study how AR size responds to climate change. Additionally, we use data from the ERA-20C reanalysis to study the relationship between lower latitude ARs and the extreme precipitation in Central-Western Mexico (CWM) during the dry season (November-March) in the 1900-2010 period.North American landfall ARs (NALFARs) that originate in the Northwest Pacific (WP) (100◦E-180◦E) have larger sizes and are more zonally oriented than those from the Northeast Pacific (EP) (180◦E-240◦E). ARs become smaller through their life cycle, mainly due to reductions in their width. They also become more meridionally oriented towards the end of their life cycle. NALFARs become smaller through their life cycle, mainly due to reductions in their width. They also become more meridionally oriented towards the end of their life cycle. Overall, the size estimation methods developed in this work provide a range of AR areas (between 7x1011m2 and 1013 m2) that is several orders of magnitude narrower than the current estimation by the AR detectors from the Atmospheric River Tracking Method Intercomparison Project (ARTMIP).From a global AR size analysis, we show an increase between 10% and 21% in the background IVT field among CMIP5/6 models. According to our results, AR width is more sensitive to climate change and has a larger contribution than length to the change in the AR area. We find a mean AR area of 3.15x106 (2.32x106-3.98x106) km2 for historical runs, and 3.42x106 (2.73x106-4.11x106) km2 for future runs. Most size estimation methods and CMIP5/6 models show positive trends in AR area, length, and width, between historical and strong radiative forcing future simulations (CMIP5: RCP-8.5, CMIP6: SSP-858). Regardless of the individual sign in AR size change, the mean AR cross-section water vapor transport increases between 8% and 37% for future simulations. Additionally, our results suggest that NALFARs are more likely to penetrate further inland under climate change.Regarding landfalling ARs in CWM, our results suggest that more than 25% of the extreme dry-season precipitation is associated with AR-like events, with up to 75% in December and January. This AR-associated precipitation is associated with an enhanced mean vertically integrated water vapor (IWV) and horizontal vapor transport (IVT) fields (30 kg m−2 and IVT 400 kg m−1s−1, respectively). The meteorological state of the atmosphere shows “ideal” conditions for orographic precipitation due to landfalling ARs: a high plume of horizontal vapor transport perpendicular to the mountain range. These events are associated with a weakening of the westward equatorial IVT and a tropospheric wave pattern, observable in the mean sea level pressure and geopotential height anomalies.We believe that the size estimation methods developed in this work provide statistical constraints for AR size and geometry, and how they change in future climates. These results could help as a reference for tuning existing ARDTs or designing new AR detection algorithms. Furthermore, we demonstrate the relationship between ARs and winter rainfall in CWM. This relationship leaves the question open of how similar are these tropical ARs to the more studied higher latitude ARs and how they will respond in a warming world.

While the terrestrial aurorae are known to be driven primarily by the interaction of the Earth's magnetosphere with the solar wind, there is considerable evidence that auroral emissions on Jupiter and Saturn are driven primarily by internal processes, with the main energy source being the planets' rapid rotation. Prior observations have suggested there might be some influence of the solar wind on Jupiter's aurorae and indicated that auroral storms on Saturn can occur at times of solar wind pressure increases. To investigate in detail the dependence of auroral processes on solar wind conditions, a large campaign of observations of these planets has been undertaken using the Hubble Space Telescope, in association with measurements from planetary spacecraft and solar wind conditions both propagated from 1 AU and measured near each planet. The data indicate a brightening of both the auroral emissions and Saturn kilometric radiation at Saturn close in time to the arrival of solar wind shocks and pressure increases, consistent with a direct physical relationship between Saturnian auroral processes and solar wind conditions. At Jupiter the correlation is less strong, with increases in total auroral power seen near the arrival of solar wind forward shocks but little increase observed near reverse shocks. In addition, auroral dawn storms have been observed when there was little change in solar wind conditions. The data are consistent with some solar wind influence on some Jovian auroral processes, while the auroral activity also varies independently of the solar wind. This extensive data set will serve to constrain theoretical models for the interaction of the solar wind with the magnetospheres of Jupiter and Saturn.

Os processos de erosão e produção de sedimentos constituem eventos de grande relevância na atualidade, ocorrendo em escala global e ocasionando prejuízos nas esferas ambiental, econômica e social. Diversas pesquisas concentram seus esforços no sentido de entender as variáveis e os condicionantes destes fenômenos, os quais vêm sendo compreendidos por meio da multidisciplinaridade de diversas áreas do conhecimento. Nesse contexto, o presente estudo teve como objetivo realizar um diagnóstico da produção de sedimentos e de seu transporte na bacia hidrográfica do Rio Itaqueri, localizada nos municípios de Itirapina e Brotas - SP, na qual está inserido o Reservatório do Lobo ou do Broa. Dentre os elementos de análise, foi utilizado o simulador hidrossedimentológico SWAT para estimar a produção de sedimentos na bacia, bem como foi realizado o monitoramento da qualidade da água, a quantificação da carga sólida em suspensão e a determinação da granulometria do material de leito em seções de amostragem localizadas nos principais tributários do reservatório. Por meio da simulação, verificou-se que ocorrem na bacia áreas com diferentes comportamentos hidrossedimentológicos, com locais onde a produção anual média de sedimentos chega a 18 t/ha e outras áreas onde esta é próxima de zero. Foi constatado que o Rio Itaqueri contribuiu com 65% do total anual médio de sedimentos que chega ao reservatório, sendo neste rio também observados os maiores valores de carga sólida em suspensão. A parte alta da bacia configurou-se como uma área de maior aporte de sedimentos na rede de drenagem, sendo os reflexos desta dinâmica observados na qualidade da água destes locais, enquanto nas áreas de médio e baixo curso evidenciou-se a predominância de processos deposicionais. Verificou-se que as análises de parâmetros de qualidade da água e de caracterização do sedimento permitiram complementar os resultados obtidos pelo SWAT, fornecendo subsídios para uma melhor compreensão da dinâmica sedimentológica da bacia. The soil erosion and the sediment yield are considered one of the biggest present environmental problems, a worldwide issue that inflicts environmental, economic and social damages. Many researches have efforts to understand the variables and constraints of these phenomenon, which have been understood through the multidisciplinarity of different areas of knowledge. In this context, this study attempts to obtain a diagnosis of sediment yield and its transport in Itaqueri River basin, in which is inserted the Lobo-Broa Reservoir. The hydrosedimentological model SWAT was used to estimate the sediment yield in the basin, as well was performed the monitoring of water quality, the quantifying of suspended-sediment discharge and the determination of bed material particle size distributions in streams. Through simulation, it was observed that occur in the basin different hydrosedimentological behaviors, where the average annual production of sediments is 18 t/ha, and its null in some places. It was observed that Itaqueri River contributed 65% of total average annual sediment reaching the reservoir, and this river also has the highest values of suspended-sediment discharge. The upper part of the basin was shown as an area of major input of sediment in drainage network, influencing the water quality in these sub-catchments, while middle course and low course of the river revealed the predominance of depositional processes. Water quality parameters and characterization of river bed sediment supplemented the results obtained by SWAT model, supporting a better understanding of hydrosedimentological processes.

Atividades antrópicas, nas últimas décadas, têm gerado quantidades significativas de resíduos, dentre os quais incluem-se elementos metálicos altamente poluentes. Desta maneira, reveste-se de grande importância o estudo dos mecanismos de fixação e mobilidade desses íons nos diferentes ambientes. Neste trabalho devido à ausência de vida aquática no Córrego da Anta, São José do Rio Preto, foram quantificados os íons poluentes metálicos oriundos de varias fontes e sua dispersão em solos, sedimentos, águas superficiais e subterrâneas; foram também avaliados riscos ecotoxicológicos em peixes considerados topo na cadeia alimentar em ecossistemas aquáticos. Foram utilizados bioindicadores, para estabelecerem-se correlações entre a distribuição dos metais pesados no ambiente físico e informações biológicas. O local de estudo compreende um trecho do Córrego da Anta, localizado no Distrito Industrial II, a noroeste do Município de São José do Rio Preto-SP. Na área têm-se um antigo lixão, encontra-se instalado um aterro sanitário, provido de sistema de captação e tratamento do chorume, uma indústria de processamento de matéria orgânica animal (sebo) e já conta com acelerado processo de ocupação antrópica. Com o objetivo de determinarem-se os mecanismos de fixação e mobilidade dos íons manganês, zinco, cobre, cromo e chumbo, foram coletadas e analisadas amostras de solos, sedimentos de fundo, águas superficiais, subterrâneas, pluviométricas e de bioindicadores. Os resultados analíticos mostraram concentrações anômalas, dos íons de interesse, especialmente nos locais onde havia lixo enterrado e no ponto de lançamento de efluente nas margens do córrego. Já nas águas superficiais e subterrâneas, excetuando-se o manganês, os teores dos cátions são bastante baixos. Através de extrações seqüenciais foram obtidos dados sobre o comportamento dos íons que, de modo geral, são semelhantes tanto para os solos das margens como para os sedimentos de fundo do Córrego, ou seja, nestes ambientes os íons acham-se associados a matéria orgânica. Os experimentos realizados com bioindicadores mostraram assimilação dos íons metálicos no tecido animal, indicando seu efeito cumulativo na cadeia alimentar. Comprovou-se também que a origem do material contaminante decididamente é oriundo dos lixos enterrados já há vários anos. Finalmente, pode-se afirmar que o chumbo e o cromo são os íons metálicos mais poluidores e encontram-se em condições latentes, apenas indisponibilizados, enquanto não ocorrerem eventos capazes de liberá-los Anthropic activities in the last decades have generated significant quantities of remains, among which highly polluting metallic elements are include. Thus it is of great importance the study of the mechanisms of fixation and mobility of these ions in different environments. In this work,due to the lack of water life in Anta Stream, São José do Rio Preto, we quantified the metallic polluting ions, from several sources and their dispersion in soils, sediments and superfial and groundwater waters. We also evaluated ecotoxicologic risks in fish, considered to be in food chains in aquatic ecosystems. Biondicators were used to establish correlations betwenn the distribution of heavy metals in the physical environment and biological information. The place of study includes a part of Antra stream located in the Industrial District II. In The northwest of São José do Rio Preto- São Paulo. In this área there is na old waste field and landfill provided with a system of captation and treatment of leachate, na industry of processing of animal organic matter (tallow) and there is a grooving process of anthropic occupation . In order to determine the fixation mechanisms and the mobility of the ions of manganese, zinc, copper,lead and chrome samples of soils, sediments of the bottom of superficial groundwater and pluviometric waters and of bioindicators were collected and analyzed. The analytical results showed anomalous concentration the interested ions, especially in places where was buried wastes and on the point of descarded of the influents of the borders or the stream. Yet, in the superficial and groundwaters waters, except for the manganese, the levels of cation were quite low. Through sequential extractions we obtained data about the behaviors or the ions which, in general, are similar to the soils of the borders and sediments of the bottom of the stream, that is in both environments the ions are associated with the organic matter. The experiments done with bioindicators showed the assimilation of the metallic ions in animal tissue, indicating its cumulative effect of the food chain. It was also proved that the origin of contaminating material definitely comes from wastes buried some years ago. Finally we can state that lead and chrome are the most polluting metallic ions and can be found in potential latent conditions, and are only not available, while events capable of freeing them, do not occur.

Indonesia is a developing country which economy relies heavily on agricultural production. From such activities a large amount of crop residues are produced each year which could be of potential for energy purposes. Unfortunately, there is an increasing concern over the open burning of biomass resources in the country and notably crop residues that are left unused in the field. Such practices lead to air pollution, human health and economic impacts. This study aimed at investigating farming practices in Indonesia for major crops and estimating the proportion of crop residues unused and subject to open burning that could potentially be available as energy feedstock. One specific location in Indonesia was selected as representative case-study and a field survey using questionnaires conducted. It was found that 21% of Indonesia's crop residues are subject to open burning. On an annual basis, this corresponds to about 45 million tonnes of residues, including, 19.3 million tonnes of rice straw, 18.5 million tonnes of cassava residues, 6.7 million tonnes of corn residues, and 0.4 million tonnes of sugarcane residues. The total energy potential such biomass could represent on a daily basis was estimated to amount to 1706 TJ.

The world has been dealing with the pressing issue of climate change, with carbon dioxide being the main offender and constituting more than 79% of all greenhouse gas emissions. Currently, over 80% of goods are being transported globally by the Maritime industry, and over 3% of the world’s GHG emissions are contributed by the Maritime industry. If the rise in GHG emissions is left uncurbed, the consequences on the environment will be catastrophic. In response to that, the IMO came up with a goal to cut GHG emissions by half by 2050. This has led to many industry players to begin adopting measures such as slow steaming, optimizing route plans, and storage of energy through batteries and cold ironing. In addition, alternative fuels have been receiving more attention as the potential reduction of GHG emissions have been found to be very significant. One such alternative fuel is Ammonia, and this research paper will aim to evaluate the economical feasibility of Ammonia as an alternative fuel throughout its entire lifecycle, which includes the production stage, storage & distribution stage, and usage stage. To get a reliable and accurate understanding of the feasibility and obstacles faced by Ammonia in becoming an alternative fuel, we conducted both primary and secondary research so that our findings were consistent and well founded. Our primary research consisted of survey responses from 54 respondents that came from varying industries and sectors. Our secondary research consisted of 4 interviews with members of the Maritime industry. The interviewees are Mr Shane Balani from Lloyd’s Register, Mr Statmatis Achillas from Wärtsilä, and 2 undisclosed individuals from PSA and Maran Asia respectively. From the data collected, analysis was conducted and the primary and secondary studies showed that there were many economical obstacles across the lifecycle of Ammonia that prevented it from being used as an alternative fuel. In the production stage of Ammonia, the main obstacles encountered were the cost of electricity being too high for Ammonia production to be feasible, and the cost of building more infrastructure and production facilities across the globe so that the demand of Ammonia could be met if it were used as an alternative fuel. The issues related to the storage & distribution stage were that the cost to design and develop infrastructure and distribution networks, as well as the materials and technology required to store Ammonia are still too costly for it to be feasible at the present moment. Lastly in the usage stage, the main obstacles would be the costs required to retrofit or design new engines and vessels capable of running on Ammonia. Overall, from the perspective of economic feasibility, Ammonia as an alternative fuel is found to be in its early stages. More studies and research have to be done to overcome the current existing obstacles, as well as any future uncertainties. For Ammonia to become a potential alternative fuel, the author has provided and discussed some recommendations. Some recommendations include the involvement of governments by providing more resources, infrastructure, and schemes to encourage innovation. The involvement of industry players by being more active in trial participation of alternative fuels, and setting funds aside for the purpose of carbon neutrality. Lastly, individuals can actively choose to buy goods from brands that use shipping companies that strive toward carbon neutrality, and insurance companies can share in the risks of the stakeholders. Bachelor of Science (Maritime Studies)

This study investigates the timing of environmental policies in free-entry mixed markets with excess burden of taxation. We consider two scenarios in which the government chooses the optimal tax before or after firms enter the market, and compare these ex-ante and ex-post taxations. When the excess burden of taxation is small (large), we find that ex-post taxation imposes a lower (higher) tax level than ex-ante taxation, which induces a larger (smaller) number of firms and a higher (lower) environmental damage. Finally, the effect of excess burden of taxation can increase the welfare, but ex-ante taxation always yields higher welfare than ex-post taxation.

Impact of Atlantic salmon (Salmo salar) cage culture in Mjoifjordur, Eastern Iceland on the chemistry of the sediment was investigated. Sediment samples were collected using a Shipek grab in December 2003. A core sub-sample was taken from each grab for analyzing total organic matter, total organic carbon, total nitrogen and phosphorus in different depths from three stations at various distances from the cage. These parameters were analyzed in the top layer of additional four stations. The results showed significant increase in all analyzed parameters in station 1, at 5m from the cage (p0.05), indicating localized impact of cage farming to the vicinity of cage. The analyzed parameters in various depth did not show significant differences (p>0.05). The value of analyzed parameters in the perimeter of the cage and their differences with reference stations showed small magnitude and localized impact on the chemistry of sediment. It might be due to deep water and moderate velocity of water current in this fjord. The magnitude of impact may differ during the summer season when biomass and feeding rate would be at the maximum level. Published

Resumo: O uso da geoquímica de gases ou emanometria é um método com grande potencial em prospecção mineral de depósitos não aflorantes e/ou encobertos por rochas não-mineralizadas, porém ainda é pouco utilizado. A temperatura de formação da mineralização é um fator determinante à presença de alguns elementos- traço, dentre eles o Hg. Existe uma predileção do Hg por depósitos de zinco de baixa temperatura do tipo epitermal e stratabound. O depósito de Zn-Pb-Cu de Santa Maria, localizado na Bacia do Camaquã, município de Caçapava do Sul (RS) contém Hg associado à mineralização e, por isso, foi escolhido como área piloto para testes de emanometria. O objetivo desta pesquisa foi medir a concentração de Hg gasoso in situ e avaliar a sua potencialidade na prospecção de depósitos sulfetados de zinco. A concentração de Hg gasoso no ar foi medida ao longo de um percurso de 11 km com um espectrômetro portátil de absorção atômica a fim de definir a concentração de Hg atmosférico local, que variou de 2 a 10 ng/m3. O Hg gasoso no solo foi medido em buracos escavados em profundidades de 30 e 50 cm e a sucção do ar para o interior do espectrômetro, atingindo valor máximo de 19 ng/m3 acima da mineralização. Amostras de solo e de duas espécies de vegetação também foram analisadas. O tratamento estatístico dos resultados mostrou que o background de Hg medido nas amostras de solo variou entre 3,9 e 28 ng/g Hg, enquanto o background obtido para as amostras de carqueja (Baccharis trimera) variou entre 10,5 e 38 ng/g Hg. Os valores de background local e o padrão de anomalia gerado demonstraram que o Hg atmosférico, o Hg gasoso (especialmente em 30 cm) e a carqueja foram os meios amostrais mais eficientes para detectar a mineralização pela medição do mercúrio. As amostras de solo e vassourinha (Dodonea viscous) geraram uma fraca resposta geoquímica da mineralização. A localização e a dimensão das anomalias de Hg puderam ser associadas à mineralização sulfetada de Santa Maria, ao sistema de Falha Três Figueiras e atividades antrópicas na área Abstract: The use of gas geochemistry or emanometry is a method with great potential in mineral exploration of deep ore deposits covered by non-mineralized rocks, although rarely used. The temperature of the mineralization is a determinant factor for the presence of certain trace elements, including Hg. There is an affinity of Hg for low temperature zinc deposits, especially epithermal and stratabounds type deposits. The Zn-Pb-Cu deposit of Santa Maria, located in Camaquã Basin, Caçapava do Sul (RS) contains Hg associated to the mineralization and was chosen as pilot area to test emanometry. The objective of this research was to measure gaseous Hg in situ and to evaluate the potentiality of its use in prospection of zinc sulfide deposits. The air Hg gas concentration was measured along a trajectory of 11 km with a portable atomic absorption spectrometer, resulting in atmospheric Hg concentrations that varied between 2 to 10 ng/m3. The Hg gas in soil was measured in holes excavated at depths of 30 and 50 cm by air suction into the spectrometer, attaining 19 ng/m3 over de mineralization. Soils and two species of vegetation were also sampled and analyzed. The statistical treatment of data showed that background Hg in soils samples varied between 3.9 and 28 ng/g, while the Hg in gorse (Baccharis trimera) varied between 10.5 and 38 ng/g. The local background values and the pattern of the anomaly showed that atmospheric Hg, gas Hg in soil (especially at 30 cm depth) and gorse were the most efficient sample media to detect the mineralization by using Hg. The soil and florida hopbush (Dodonea viscous) produced a weak geochemical response of the mineralization. The location and the dimension of Hg anomalies could be associated to the Santa Maria deposit, to the Três Figueiras fault system and to anthropogenic activities in the area Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências Orientadores: Jacinta Enzweiler, Otávio Augusto Boni Licht Geologia e Recursos Naturais Mestra em Geociências Mestrado