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Topic Review
DPSIR Assessment on Ecosystem Services
The DPSIR framework (Driver – Pressure – State – Impact – Response) is a useful tool to assess and investigate the cause-effect within an ecosystem to aid better systems - thinking approach for stakeholders, policymakers and governance managers to draft response measures. The DPSIR framework helps to identify and analyse the different effects of human activities over the ecosystem services and human well-being in the different ecosystems such as estuarine, delta, river, coastal, etc. The varied human activities involves mining, construction, fishing, infrastructure development, etc. The DPSIR study shows a holistic view on several interlinked pressures and state changes in the ecosystems, also supporting the development of some potential responses to form systematic, sustainable approaches for mitigating and adapting the impacts caused by human activities. This contribution describes the application of DPSIR framework to study the impacts of sand mining and sand consumption in the Vietnam's Mekong Delta ecosystem services, 
  • 1.4K
  • 25 Nov 2020
Topic Review
Submarine Canyon
A submarine canyon is a steep-sided valley cut into the seabed of the continental slope, sometimes extending well onto the continental shelf, having nearly vertical walls, and occasionally having canyon wall heights of up to 5 km, from canyon floor to canyon rim, as with the Great Bahama Canyon. Just as above-sea-level canyons serve as channels for the flow of water across land, submarine canyons serve as channels for the flow of turbidity currents across the seafloor. Turbidity currents are flows of dense, sediment laden waters that are supplied by rivers, or generated on the seabed by storms, submarine landslides, earthquakes, and other soil disturbances. Turbidity currents travel down slope at great speed (as much as 70 km/h), eroding the continental slope and finally depositing sediment onto the abyssal plain, where the particles settle out. About 3% of submarine canyons include shelf valleys that have cut transversely across continental shelves, and which begin with their upstream ends in alignment with and sometimes within the mouths of large rivers, such as the Congo River and the Hudson Canyon. About 28.5% of submarine canyons cut back into the edge of the continental shelf, whereas the majority (about 68.5%) of submarine canyons have not managed at all to cut significantly across their continental shelves, having their upstream beginnings or "heads" on the continental slope, below the edge of continental shelves. The formation of submarine canyons is believed to occur as the result of at least two main process: 1) erosion by turbidity current erosion; and 2) slumping and mass wasting of the continental slope. While at first glance, the erosion patterns of submarine canyons may appear to mimic those of river-canyons on land, due to the markedly different erosion processes that have been found to take place underwater at the soil/ water interface, several notably different erosion patterns have been observed in the formation of typical submarine canyons. Many canyons have been found at depths greater than 2 km below sea level. Some may extend seawards across continental shelves for hundreds of kilometres before reaching the abyssal plain. Ancient examples have been found in rocks dating back to the Neoproterozoic. Turbidites are deposited at the downstream mouths or ends of canyons, building an abyssal fan.
  • 1.4K
  • 09 Nov 2022
Topic Review
Carbon Sequestration
Carbon sequestration or carbon dioxide removal (CDR) is the long-term removal, capture or sequestration of carbon dioxide from the atmosphere to slow or reverse atmospheric CO2 pollution and to mitigate or reverse global warming. Carbon dioxide (CO2) is naturally captured from the atmosphere through biological, chemical, and physical processes. These changes can be accelerated through changes in land use and agricultural practices, such as converting crop and livestock grazing land into land for non-crop fast growing plants. Artificial processes have been devised to produce similar effects, including large-scale, artificial capture and sequestration of industrially produced CO2 using subsurface saline aquifers, reservoirs, ocean water, aging oil fields, or other carbon sinks, bio-energy with carbon capture and storage, biochar, ocean fertilization, enhanced weathering, and direct air capture when combined with storage. The likely need for CDR has been publicly expressed by a range of individuals and organizations involved with climate change issues, including IPCC chief Rajendra Pachauri, the UNFCCC executive secretary Christiana Figueres, and the World Watch Institute. Institutions with major programs focusing on CDR include the Lenfest Center for Sustainable Energy at the Earth Institute, Columbia University, and the Climate Decision Making Center, an international collaboration operated out of Carnegie-Mellon University's Department of Engineering and Public Policy.
  • 1.4K
  • 28 Nov 2022
Topic Review
Radar-based Rainfall Information
Radar-based rainfall information has been widely used in hydrological and meteorological applications, as it provides data with a high spatial and temporal resolution that improve rainfall representation. However, the broad diversity of studies makes it difficult to gather a condensed overview of the usefulness and limitations of radar technology and its application in particular situations. 
  • 1.4K
  • 22 Feb 2021
Topic Review
Instrumental Temperature Record
The instrumental temperature record provides the temperature of Earth's climate system from the historical network of in situ measurements of surface air temperatures and ocean surface temperatures. Data are collected at thousands of meteorological stations, buoys and ships around the globe. The longest-running temperature record is the Central England temperature data series, which starts in 1659. The longest-running quasi-global record starts in 1850. In recent decades, more extensive sampling of ocean temperatures at various depths allows estimates of ocean heat content, but these samples do not form part of the global surface temperature datasets.
  • 1.4K
  • 25 Nov 2022
Topic Review
Sustainable Consumption of Food
The 2030 Agenda for Sustainable Development provides a global blueprint for dignity, peace, and prosperity for people and the planet, now and in the future. At its heart are the 17 Sustainable Development Goals (SDGs) as an urgent call to action by all countries—developed and developing—in a global partnership. The fact that food is the basic resource for life highlights the need for a comprehensive goal that can be achieved by reducing food waste, promoting healthy and balanced nutrition, raising awareness of the society on responsible food consumption and developing policies on food consumption by regulatory authorities in connection with ensuring the sustainability of food consumption. Therefore, ensuring sustainable food consumption can also be seen as a generic goal that can be supported by almost all SDGs. 
  • 1.4K
  • 20 Jul 2021
Topic Review
17O in Hydrological Cycle
17O is the one of the naturally occurring stable isotopes of oxygen, and also it has the lowest abundance, 0.038%(). The distribution of isotopes in hydrological systems is controlled by isotope fractionation processes. Oxygen isotopes fractionate through mass-dependent isotopic fractionation, which includes kinetic processes, isotopic exchange reactions, and physicochemical phenomena (diffusion, condensation, and evaporation).
  • 1.4K
  • 03 Aug 2021
Topic Review
"Zorbas" on Southeastern Sicily
Over the last few years, several authors have presented contrasting models to describe the response of boulders to extreme waves, but the absence of direct observation of movements has hindered the evaluation of these models. The recent development of online video-sharing platforms in coastal settings has provided the opportunity to monitor the evolution of rocky coastlines during storm events. In September 2018, a surveillance camera of the Marine Protected Area of Plemmirio recorded the movement of several boulders along the coast of Maddalena Peninsula (Siracusa, Southeastern Sicily) during the landfall of the Mediterranean tropical-like cyclone (Medicane) Zorbas. Unmanned autonomous vehicle (UAV) photogrammetric and terrestrial laser scanner (TLS) surveys were performed to reconstruct immersive virtual scenarios to geometrically analyze the boulder displacements recorded in the video. Analyses highlighted that the displacements occurred when the boulders were submerged as a result of the impact of multiple small waves rather than due to a single large wave. Comparison between flow velocities obtained by videos and calculated through relationships showed a strong overestimation of the models, suggesting that values of flow density and lift coefficient used in literature are underestimated.
  • 1.4K
  • 25 Aug 2021
Topic Review
Map Projections Classification
Many books, textbooks and papers have been published in which the classification of map projections is based on auxiliary (developable) surfaces and projections are divided into conic, cylindrical and azimuthal projections.
  • 1.4K
  • 13 Jun 2022
Topic Review
Dilophosaurus
Dilophosaurus (/daɪˌloʊfəˈsɔːrəs, -foʊ-/ dy-LOH-fə-SOR-əs, -⁠foh-) is a genus of theropod dinosaurs that lived in what is now North America during the Early Jurassic, about 193 million years ago. Three skeletons were discovered in northern Arizona in 1940, and the two best preserved were collected in 1942. The most complete specimen became the holotype of a new species in the genus Megalosaurus, named M. wetherilli by Samuel P. Welles in 1954. Welles found a larger skeleton belonging to the same species in 1964. Realizing it bore crests on its skull, he assigned the species to the new genus Dilophosaurus in 1970, as Dilophosaurus wetherilli. The genus name means "two-crested lizard", and the species name honors John Wetherill, a Navajo councilor. Further specimens have since been found, including an infant. Footprints have also been attributed to the animal, including resting traces. Another species, Dilophosaurus sinensis from China, was named in 1993, but was later found to belong to the genus Sinosaurus. At about 7 m (23 ft) in length, with a weight of about 400 kg (880 lb), Dilophosaurus was one of the earliest large predatory dinosaurs and the largest known land-animal in North America at the time. It was slender and lightly built, and the skull was proportionally large, but delicate. The snout was narrow, and the upper jaw had a gap or kink below the nostril. It had a pair of longitudinal, arched crests on its skull; their complete shape is unknown, but they were probably enlarged by keratin. The mandible was slender and delicate at the front, but deep at the back. The teeth were long, curved, thin, and compressed sideways. Those in the lower jaw were much smaller than those of the upper jaw. Most of the teeth had serrations at their front and back edges. The neck was long, and its vertebrae were hollow, and very light. The arms were powerful, with a long and slender upper arm bone. The hands had four fingers; the first was short but strong and bore a large claw, the two following fingers were longer and slenderer with smaller claws; the fourth was vestigial. The thigh bone was massive, the feet were stout, and the toes bore large claws. Dilophosaurus is a member of the family Dilophosauridae along with Dracovenator, a group placed between the Coelophysidae and later theropods. Dilophosaurus would have been active and bipedal, and may have hunted large animals; it could also have fed on smaller animals and fish. Due to the limited range of movement and shortness of the forelimbs, the mouth may instead have made first contact with prey. The function of the crests is unknown; they were too weak for battle, but may have been used in visual display, such as species recognition and sexual selection. It may have grown rapidly, attaining a growth rate of 30 to 35 kg (66 to 77 lb) per year early in life. The holotype specimen had multiple paleopathologies, including healed injuries and signs of a developmental anomaly. Dilophosaurus is known from the Kayenta Formation, and lived alongside dinosaurs such as Megapnosaurus and Sarahsaurus. Dilophosaurus was featured in the novel Jurassic Park and its movie adaptation, wherein it was given the fictional abilities to spit venom and expand a neck frill, as well as being smaller than the real animal. It was designated as the state dinosaur of Connecticut based on tracks found there.
  • 1.4K
  • 18 Oct 2022
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