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Upwelling processes bring nutrient-rich waters from the deep ocean to the surface. Areas of upwelling are often associated with high productivity, offering great economic value in terms of fisheries. The sensitivity of spring/summer-time coastal upwelling systems to climate change has recently received a lot of attention. Several studies have suggested that their intensity may increase in the future while other authors have shown decreasing intensity in their equatorward portions. Yet, recent observations do not show robust evidence of this intensification. The Senegalo-Mauritanian upwelling system (SMUS) located at the southern edge of the north Atlantic system (12°N–20°N) and most active in winter/spring has been largely excluded from these studies. Here, the seasonal cycle of the SMUS and its response to climate change is investigated in the database of the Coupled Models Inter comparison Project Phase 5 (CMIP5). Upwelling magnitude and surface signature are characterized by several sea surface temperature and wind stress indices. We highlight the ability of the climate models to reproduce the system, as well as their biases. The simulations suggest that the intensity of the SMUS winter/spring upwelling will moderately decrease in the future, primarily because of a reduction of the wind forcing linked to a northward shift of Azores anticyclone and a more regional modulation of the low pressures found over Northwest Africa. The implications of such an upwelling reduction on the ecosystems and local communities exploiting them remains very uncertain.

As an archipelago, Indonesia has thousands of islands and stretched coastlines. It is, therefore, Indonesia has many mangroves as a characteristic of plants exists on the coast. There have been many studies and trials of mangrove utilization for economic and ecological purposes, yet it is limited use of mangroves for educational purposes. This study aims to promote the mangrove ecosystem for educational purposes, particularly as a source of biology learning, increase students ’interest in studying biology, and increase students’ interest in conserving mangroves. This study used a qualitative approach with three instruments, namely observation, interview and questionnaire. The result indicated that the mangrove ecosystem could be used as a source of learning biology and be able to increase students’ interest in studying biology and conserving mangroves.

Abstract Carbon capture, utilization, and storage (CCUS) is one of several mitigation options that must be implemented in order to reduce anthropogenic CO 2 emissions. The work presented in this paper is a part of the ongoing PRO_CCS project, where the emphasis is on Polish emitters located on or close to the Baltic Sea coast and possible whole chain CCS solutions for these. This paper will focus on the potential use of CO 2 from these sources in CO 2 -EOR projects in the Baltic Sea and/or North Sea. In addition, a number of technical and non-technical CO 2 -EOR related aspects have been identified and discussed. Two oilfields, B8 in the Polish economic sector of the Baltic Sea and Brage on the Norwegian Continental Shelf have been selected. These two fields are matched with suitable emitters in Poland to develop two separate CCUS scenarios. The scenarios will provide a prediction on operations during the CO 2 -EOR project lifetime. These predictions will be based on open information about the oilfields and their current operation, and on available literature on CO 2 -EOR operations. The goal of the project is to assess the economic viability of the two scenarios.

Recent geomorphic evidence from the inner shelf and shoreface to the east of Long Island's barrier island system indicates that reworking of glacial outwash deposits at the inner shelf-shoreface transition, as sea level rises, may be supplying much of the sediment needed to maintain barrier islands to the west. A conceptual model describing sediment dispersal from outwash source areas was developed from this hypothesis. It was reasoned that outwash sediments ranging from silts to coarse gravels would be subject to differential transport paths across and along the shoreface upon reworking. Coarser grain sizes would move onshore toward the intertidal beach, whereas finer sediments would move offshore. Sand of intermediate grain size would be concentrated in the surf zone an move alongshore in wave-generated longshore currents. To test this model, 400 samples from the beach and shoreface of Long Island were analyzed for grain-size frequency distribution and each grain-size class was examined for frequency of occurrence in the cross-shore and alongshore directions. On a spatially averaged basis, grain-size classes displayed peak abundance in specific zones across the shoreface as predicted by the model, but alongshore trends could not be recognized among the "noisy" data. Therefore, empirical orthogonal functions (EOF) were used to examine uncorrelated (orthogonal) modes of variability in the occurrence of each grain-size class in the alongshore direction. The first function, representing more than 60% of the variability among the data, showed that grain sizes subject to longshore transport in the surf zone i crease in frequency in the alongshore direction relative to coarser grain sizes. Results also show that peak concentrations of coarse sediments correspond to zones subject to frequent overwashing. It is concluded that EOF analysis of individual grain-size classes holds promise for extracting trends from noisy data sets. End_of_Article - Last_Page 318------------

We utilize a variety of climate datasets to examine impacts of two mechanisms on precipitation in the Greater Horn of Africa (GHA) during northern-hemisphere summer. First, surface-pressure gradients draw moist air toward the GHA from the tropical Atlantic Ocean and Congo Basin. Variability of the strength of these gradients strongly influences GHA precipitation totals and accounts for important phenomena such as the 1960s–1980s rainfall decline and devastating 1984 drought. Following the 1980s, precipitation variability became increasingly influenced by the southern tropical Indian Ocean (STIO) region. Within this region, increases in sea-surface temperature, evaporation, and precipitation are linked with increased exports of dry mid-tropospheric air from the STIO region toward the GHA. Convergence of dry air above the GHA reduces local convection and precipitation. It also produces a clockwise circulation response near the ground that reduces moisture transports from the Congo Basin. Because precipitation originating in the Congo Basin has a unique isotopic signature, records of moisture transports from the Congo Basin may be preserved in the isotopic composition of annual tree rings in the Ethiopian Highlands. A negative trend in tree-ring oxygen-18 during the past half century suggests a decline in the proportion of precipitation originating from the Congo Basin. This trend may not be part of a natural cycle that will soon rebound because climate models characterize Indian Ocean warming as a principal signature of greenhouse-gas induced climate change. We therefore expect surface warming in the STIO region to continue to negatively impact GHA precipitation during northern-hemisphere summer.

Abstract In some shelf sea regions of the world, the tidal range is sufficient to convert the potential energy of the tides into electricity via tidal range power plants. As an island continent, Australia is one such region – a previous study estimated that Australia hosts up to 30% of the world’s resource. Here, we make use of a gridded tidal dataset (TPXO9) to characterize the tidal range resource of Australia. We examine the theoretical resource, and we also investigate the technical resource through 0D modelling with tidal range power plant operation. We find that the tidal range resource of Australia is 2004 TWh/yr, or about 22% of the global resource. This exceeds Australia’s total energy consumption for 2018/2019 (1721 TWh/yr), suggesting tidal range energy has the potential to make a substantial contribution to Australia’s electricity generation (265 TWh/yr in 2018/2019). Due to local resonance, the resource is concentrated in the sparsely populated Kimberley region of Western Australia. However, the tidal range resource in this region presents a renewable energy export opportunity, connecting to markets in southeast Asia. Combining the electricity from two complementary sites, with some degree of optimization tidal range schemes in this region can produce electricity for 45% of the year.

Biodiversity analysis underlies macroevolutionary studies and allows to identify mass extinctions. Numerous studies of mass extinctions show that geological factors play a central role in determining the diversity dynamics. The late Cretaceous extinction is of interest to science as the closest to us extinction of the five mass extinctions that occurred in the Phanerozoic. There is currently no scientific consensus on the scenario in which the extinction occurred on land. In order to assess the features of superorderDinosauriadevelopment during the Cretaceous-Paleogene, the authors have analysed the diversity of terrestrial taxa of Mesozoic dinosaurs. Based on data from the paleobiodb paleontological database using the Python programming language and its libraries, the features of the species diversity ofDinosauriahave been studied. An attempt was made to quantify the species diversity of this group based on the ratio of predators to herbivores using data on dinosaur food types. The simulated diversity data were compared with observed patterns and existing estimates. It is likely that less than one-third of the dinosaurs that existed are currently known, as indicated by the geography of the fossils, and the proportions of dinosaurs by type of diet.