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Topic Review
Cleveland-Lloyd Dinosaur Quarry
The Cleveland-Lloyd Dinosaur Quarry, well known for containing the densest concentration of Jurassic dinosaur fossils ever found, is a paleontological site located near Cleveland, Utah, in the San Rafael Swell, a part of the geological layers known as the Morrison Formation. Well over 15,000 bones have been excavated from this Jurassic excavation site and there are many thousands more awaiting excavation and study. It was designated a National Natural Landmark in October 1965. All of these bones, belonging to different species, are found disarticulated and indistinctly mixed together. It has been hypothesised that this strong concentration of mixed fossilised bones is due to a "predator trap", but any kind of definitive scientific consensus hasn't been reached yet and debates still continue to the present day.
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Topic Review
Gulf of Mexico Basin
The formation of the Gulf of Mexico, an oceanic rift basin located between North America and the Yucatan Block, was preceded by the breakup of the Supercontinent Pangaea in the Late-Triassic, weakening the lithosphere. Rifting between the North and South American plates continued in the Early-Jurassic, approximately 160 million years ago, and formation of the Gulf of Mexico, including subsidence due to crustal thinning, was complete by 140 Ma. Stratigraphy of the basin, which can be split into several regions, includes sediments deposited from the Jurassic through the Holocene, currently totaling a thickness between 15 and 20 kilometers.
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Topic Review
Archaeology of Wales
The Archaeology of Wales is the study of human occupation within the country of Wales, which has been occupied by modern humans since 225,000 BCE, with continuous occupation from 9,000 BCE. Analysis of the sites, artifacts and other archaeological data within Wales details its complex social landscape and evolution from Prehistoric times to the Industrial period. This study is undertaken by academic institutions, consultancies, charities as well as government organisations.
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Topic Review
Clean Development Mechanism
The Clean Development Mechanism (CDM) is one of the Flexible Mechanisms defined in the Kyoto Protocol (IPCC, 2007) that provides for emissions reduction projects which generate Certified Emission Reduction units (CERs) which may be traded in emissions trading schemes. The market crashed in 2012 when the value of credits collapsed and thousands of projects were left with unclaimed credits. The struggle about what to do with the old credits sank the 2019 COP 25 in Madrid. The CDM, defined in Article 12 of the Protocol, was intended to meet two objectives: "Annex I" parties are the countries listed in Annex I of the treaty, the industrialized countries. Non-Annex I parties are developing countries. The CDM addresses the second objective by allowing the Annex I countries to meet part of their emission reduction commitments under the Kyoto Protocol by buying Certified Emission Reduction units from CDM emission reduction projects in developing countries. Both the projects and the issue of CERs units are subject to approval to ensure that these emission reductions are real and "additional." The CDM is supervised by the CDM Executive Board (CDM EB) under the guidance of the Conference of the Parties (COP/MOP) of the United Nations Framework Convention on Climate Change (UNFCCC). The CDM allows industrialized countries to buy CERs and to invest in emission reductions where it is cheapest globally. Between 2001, which was the first year CDM projects could be registered and 7 September 2012, the CDM issued 1 billion Certified Emission Reduction units. As of 1 June 2013, 57% of all CERs had been issued for projects based on destroying either HFC-23 (38%) or N2O (19%). Carbon capture and storage (CCS) was included in the CDM carbon offsetting scheme in December 2011. However, a number of weaknesses of the CDM have been identified. Several of these issues were addressed by the new Program of Activities (PoA), which moves to approving 'bundles' of projects instead of accrediting each project individually. In 2012, the report Climate Change, Carbon Markets and the CDM: A Call to Action said governments urgently needed to address the future of the CDM. It suggested the CDM was in danger of collapse because of the low price of carbon and the failure of governments to guarantee its existence into the future. Writing on the website of the Climate & Development Knowledge Network, Yolanda Kakabadse, a member of the investigating panel for the report and founder of Fundación Futuro Latinamericano, said a strong CDM is needed to support the political consensus essential for future climate progress. "Therefore we must do everything in our hands to keep it working," she said.
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Topic Review
Atmospheric Carbon Cycle
The atmosphere is one of the Earth's major carbon reservoirs and an important component of the global carbon cycle, holding approximately 720 gigatons of carbon. Atmospheric carbon plays an important role in the greenhouse effect. The most important carbon compound in this respect is the gas carbon dioxide (CO2). Although it is a small percentage of the atmosphere (approximately 0.04% on a molar basis), it plays a vital role in retaining heat in the atmosphere and thus in the greenhouse effect. Other gases with effects on the climate containing carbon in the atmosphere are methane and chlorofluorocarbons (the latter is entirely anthropogenic). Emissions by humans in the past 200 years have almost doubled the amount carbon dioxide in the atmosphere.
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Topic Review
Gorgonopsia
Gorgonopsia (from the Greek Gorgon, a mythological beast, and óps 'aspect') is an extinct clade of sabre-toothed therapsids from the Middle to Upper Permian roughly 265 to 252 million years ago. They are characterised by a long and narrow skull, as well as elongated upper and sometimes lower canine teeth and incisors which were likely used as slashing and stabbing weapons. Postcanine teeth are generally reduced or absent. For hunting large prey, they possibly used a bite-and-retreat tactic, ambushing and taking a debilitating bite out of the target, and following it at a safe distance before its injuries exhausted it, whereupon the gorgonopsian would grapple the animal and deliver a killing bite. They would have had an exorbitant gape, possibly in excess of 90°, without having to unhinge the jaw. They markedly increased in size as time went on, growing from small skull lengths of 10–15 cm (4–6 in) in the Middle Permian to bear-like proportions of up to 60 cm (2 ft) in the Upper Permian. The latest gorgonopsians, Rubidgeinae, were the most robust of the group and could produce especially powerful bites. Gorgonopsians are thought to have been completely terrestrial and could walk with a semi-erect gait, with a similar terrestrial locomotory range as modern crocodilians. They may have been more agile than their prey items, but were probably inertial homeotherms rather than endotherms unlike contemporary therocephalians and cynodonts, and thus were probably comparatively less active. Though gorgonopsians were able to maintain a rather high body temperature, it is unclear if they would have also had sweat glands or fur (and by extension whiskers and related structures). Their brains were reminiscent of modern reptilian brains, rather than those of living mammals. Most species may have been predominantly diurnal (active during the day) though some could have been crepuscular (active at dawn or dusk) or nocturnal (active at night). They are thought to have had binocular vision, a parietal eye (which detects sunlight and maintains circadian rhythm), a keen sense of smell, a functional vomeronasal organ ("Jacobson's organ"), and possibly a rudimentary eardrum. The major therapsid groups had all evolved by 275 million years ago from a "pelycosaur" ancestor (a poorly defined group including all synapsids which are not therapsids). The therapsid takeover from pelycosaurs took place by the Middle Permian as the world progressively became drier. Gorgonopsians rose to become apex predators of their environments following the Capitanian mass extinction event which killed off the dinocephalians and some large therocephalians after the Middle Permian. Despite the existence of a single continent during the Permian, Pangaea, gorgonopsians have only been found in the Karoo Supergroup (primarily in South Africa, but also in Tanzania, Zambia, and Malawi), the Moradi Formation of Niger, and western Russia, with probable remains known from the Kundaram Formation of India. These places were semi-arid areas with highly seasonal rainfall. Gorgonopsian genera vary very little, and consequently, many species have been named based on flimsy and likely age-related differences since their discovery in the late 19th century, and the group has been subject to several taxonomic revisions. They became extinct during a phase of the Permian–Triassic extinction event taking place at the very end of the Permian, in which major volcanic activity (which would produce the Siberian Traps) and resultant massive spike in greenhouse gases caused rapid aridification due to temperature spike, acid rain, frequent wildfires, and potential breakdown of the ozone layer. The large predatory niches would be taken over by the archosaurs (namely crocodilians and dinosaurs) in the Mesozoic.
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Topic Review
Appalachia (Mesozoic)
During most of the Late Cretaceous (100.5 to 66 million years ago) the eastern half of North America formed Appalachia (named for the Appalachian Mountains), an island land mass separated from Laramidia to the west by the Western Interior Seaway. This seaway had split North America into two massive landmasses due to a multitude of factors such as tectonism and sea-level fluctuations for nearly 40 million years. seaway eventually exapanded, divided across the Dakotas, and by the end of the Cretaceous, it retreated towards the Gulf of Mexico and the Hudson Bay. This left the island masses joined in the continent of North America as the Rocky Mountains rose. From the Cenomanian to the end of the Campanian ages of the Late Cretaceous, Appalachia was separated from the rest of North America. As the Western Interior Seaway retreated in the Maastrichtian, Laramidia and Appalachia eventually connected. Because of this, its fauna was isolated, and developed very differently from the tyrannosaur, ceratopsian, hadrosaurid, pachycephalosaur and ankylosaurid dominated fauna of the western part of North America, known as "Laramidia". Due to the fact that Appalachia was largely flat and had less erosion compared to Laramidia, no terrestrially formed deposits have survived, with most dinosaur remains originating from seaborne carcasses that were transported into marine environments. Some sediments have been removed by glacial erosion during the last ice age, but it is difficult to ascertain how much sediment has been removed, or whether these sediments would have been any more productive than those that remain. Thus relatively little is known about Appalachia in comparison to Laramidia, with exception of plant life, marine life and the insects trapped in amber from New Jersey. In addition, due to a lack of interest in Appalachia, many fossils that have been found in Appalachia lie unstudied and remain in the inaccurate genera to which they were assigned in the days of E. D. Cope and O. C. Marsh. Only a few fossils of the terrestrial creatures that were found in this region have given us a brief glimpse into what life was like here during the Cretaceous period. However, the area has seen a bit of a resurgence of interest due to several discoveries made in the past few years. As mentioned earlier, not much is known about Appalachia, but some fossil sites, such as the Woodbine Formation, Navesink Formation, Ellisdale Fossil Site, Mooreville Chalk Formation, Demopolis Chalk Formation, Black Creek Group and the Niobrara Formation, together with ongoing research in the area, have given us a better look into this forgotten world of paleontology.
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Topic Review
Adaptation to Climate Change in Jordan
Adaptation to climate change in Jordan describes measures with the objective to prepare the country for the impacts of climate change. Water resources in Jordan are scarce. Besides the rapid population growth, the impacts of climate change are likely to further exacerbate the problem. Temperatures will increase and the total annual precipitation is likely to decrease, however with a fair share of uncertainty. Hence, existing and new activities with the objective to minimize the gap between water supply and demand contribute to adapt Jordan to tomorrow's climate. This might be accompanied by activities improving Jordan's capacity to monitor and project meteorological and hydrological data and assess its own vulnerability to climate change. This article focuses on the impacts of climate change on the Jordanian water sector.
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Topic Review
Spruce-fir Forests
Fir and spruce forests are greatly affected by slight fluctuations in climate. Temperature is the primary determinate for spatial patterns of fir and spruce. The two dominant trees in this type of forest are Picea engelmannii (Engelmann spruce) and Abies lasiocarpa (subalpine fir). Although thick-barked trees, such as the Pinus resinosa, frequently survive fire, the thin bark of spruce make them more vulnerable. Trees such as the Douglas fir withstand much of the fire due to the thicker bark they have. The scale of the burn mosaic during a fire, relative to species niche requirements and mobility, can have major impacts on flora and fauna dynamics.
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Topic Review
Mangalore
Mangalore (/mæŋɡəˈlɔːr/), officially known as Mangaluru, is a major port city of the Indian state of Karnataka. It is located between the Arabian Sea and the Western Ghats about 352 km (219 mi) west of Bangalore, the state capital, 20 km north of Karnataka–Kerala border, 297 km south of Goa. Mangalore is the state's only city to have all four modes of transport—air, road, rail and sea. The population of the urban agglomeration was 619,664 (As of 2011) national census of India. It is known for being one of the locations of the Indian strategic petroleum reserves. The city developed as a port in the Arabian Sea during ancient times; it has since developed into a major port of India that handles 75 per cent of India's coffee and cashew exports, and is the country's seventh largest container port. Mangalore has been ruled by several major powers, including the Kadambas, Alupas, Vijayanagar Empire, Keladi Nayaks and the Portuguese. The city was a source of contention between the British and the Kingdom of Mysore rulers Hyder Ali and Tipu Sultan, and was eventually annexed by the British in 1799. Mangalore remained part of the Madras Presidency until India's independence in 1947 and was unified with Mysore State (now called Karnataka) in 1956. Mangalore is also the administrative headquarters of the Dakshina Kannada district, and is a commercial, industrial, educational, healthcare and startup hub. This city's International Airport is the second-largest and second-busiest airport in Karnataka. Mangalore City Corporation is responsible for the civic administration, which manages the 60 wards of the city. The city's landscape is characterised by rolling hills, coconut palms, rivers and hard laterite soil. India's first 3D planetarium with 8K resolution display is situated in this city. Mangalore is also included in the Smart Cities Mission list and is among the 100 smart cities to be developed in India. The city has an average elevation of 22 m (72 ft) above mean sea level. Mangalore has a tropical monsoon climate and is under the influence of the southwest monsoon. (As of 2017), Mangalore was ranked the 48th best city to live in the world by a US survey, and the only Indian city in the top 50.
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