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Topic Review
Oceania
Oceania (UK: /ˌoʊsiˈɑːniə, ˌoʊʃi-, -ˈeɪn-/, US: /ˌoʊʃiˈæniə/ (listen), /-ˈɑːn-/) is a geographical region that includes Australasia, Melanesia, Micronesia, and Polynesia. Spanning the Eastern and Western hemispheres, Oceania is estimated to have a land area of 8,525,989 square kilometres (3,291,903 sq mi)[discuss] and a population of over 41 million. When compared with the other continents, the region of Oceania is the smallest in land area and the second smallest in population after Antarctica. Its six major population centres are Sydney, Melbourne, Brisbane, Perth, Auckland, and Adelaide. Oceania has a diverse mix of economies from the highly developed and globally competitive financial markets of Australia , French Polynesia, Hawaiʻi, New Caledonia, and New Zealand, which rank high in quality of life and Human Development Index, to the much less developed economies of Kiribati, Papua New Guinea, Tuvalu, Vanuatu, and Western New Guinea, while also including medium-sized economies of Pacific islands such as Fiji, Palau, and Tonga. The largest and most populous country in Oceania is Australia, and the largest city is Sydney. Puncak Jaya in Papua is the highest peak in Oceania at 4,884 m (16,024 ft). The first settlers of Australia, New Guinea, and the large islands just to the east arrived more than 60,000 years ago. Oceania was first explored by Europeans from the 16th century onward. Portuguese explorers, between 1512 and 1526, reached the Tanimbar Islands, some of the Caroline Islands and west Papua New Guinea. On his first voyage in the 18th century, James Cook, who later arrived at the highly developed Hawaiʻian Islands, went to Tahiti and followed the east coast of Australia for the first time. The arrival of European settlers in subsequent centuries resulted in a significant alteration in the social and political landscape of Oceania. The Pacific theatre saw major action during the Second World War, mainly between Allied powers the United States, Philippines (a US Commonwealth at the time) and Australia, and Axis power Japan. The rock art of Aboriginal Australians is the longest continuously practiced artistic tradition in the world. Most Oceanian countries are multi-party representative parliamentary democracies, with tourism being a large source of income for the Pacific Islands nations.
  • 17.6K
  • 03 Mar 2023
Topic Review
Application of Google Earth Engine
Google Earth Engine (GEE) is a cloud computing platform that was launched by Google in 2010. Since then, GEE has demonstrated its capacity of preprocessing and mining of geographic big data. GEE enables cloud computation and is an effective tool for carrying out the analysis of global geospatial big data.
  • 4.0K
  • 08 Oct 2021
Topic Review
Carcharodontosaurus
Carcharodontosaurus (/ˌkɑːrkəroʊˌdɒntoʊˈsɔːrəs/; lit. sharp-toothed lizard) is a genus of large carcharodontosaurid theropod dinosaur that existed during the Cenomanian age of the Late Cretaceous in Northern Africa. The genus Carcharodontosaurus is named after the shark genus Carcharodon, itself composed of the Greek karchar[os] (κάρχαρος, meaning "jagged" or "sharp") and odōn (ὀδών, "teeth"), and the suffix -saurus ("lizard"). It is currently known to have two species: C. saharicus and C. iguidensis.
  • 3.6K
  • 09 Nov 2022
Topic Review
Early Chinese Cartography
Early Chinese cartography began in the 5th century BC during the Warring States period when cartographers started to make maps of the Earth's surface. Its scope extended beyond China's borders with the expansion of the Chinese Empire under the Han dynasty. It entered its golden age with the invention of the compass in the 11th century during the Song dynasty, and reached its peak in the 15th century when the Ming dynasty admiral Zheng He went on a series of voyages to the South China Sea, Indian Ocean, and beyond.
  • 3.2K
  • 10 Oct 2022
Topic Review
Adaptation
The term “adaptation” is currently used in the climate field. It originated from natural science in the field of population biology and evolutionary ecology. It originally referred to the general characteristics that ensure the survival and reproduction of organic individuals in living environments. The definition of “adaptation” has many attributes, including the two most important points. First is the spatial scale of adaptation, which depends on who is responsible. Second is the nature of adaptive behavior, whether it is spontaneous or conscious or it is planned or prescriptive. The former is usually short-term and tactical adaptation, which is directly related to specific climate change. The latter is more strategic, long-term, and proactive and is usually formulated by government departments and used as part of policy adaptation measures. The adaptation to climate change in the literature is sometimes divergent at the temporal and spatial scales. Short-term adaptation is more of a reaction, and higher-scale adaptation is considered an expected adaptation through policies, projects, and recent plans and actions.
  • 3.2K
  • 15 Nov 2021
Topic Review
Triangulation Station
A triangulation station, also known as a triangulation pillar, trigonometrical station, trigonometrical point, trig station, trig beacon, or trig point, and sometimes informally as a trig, is a fixed surveying station, used in geodetic surveying and other surveying projects in its vicinity. The nomenclature varies regionally: they are generally known as trigonometrical or triangulation stations in North America, trig points in the United Kingdom, trig pillars in Ireland, trig stations or points in Australia and New Zealand, and trig beacons in South Africa; triangulation pillar is the more formal term for the concrete columns found in the UK.
  • 3.1K
  • 02 Dec 2022
Topic Review
Allosaurus
Allosaurus (/ˌæləˈsɔːrəs/) is a genus of large carnosaurian theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic epoch (Kimmeridgian to late Tithonian). The name "Allosaurus" means "different lizard" alluding to its unique (at the time of its discovery) concave vertebrae. It is derived from the Greek ἄλλος (allos) ("different, other") and σαῦρος (sauros) ("lizard / generic reptile"). The first fossil remains that could definitively be ascribed to this genus were described in 1877 by paleontologist Othniel Charles Marsh. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles. Allosaurus was a large bipedal predator. Its skull was light, robust and equipped with dozens of sharp, serrated teeth. It averaged 8.5 meters (28 ft) in length for A. fragilis, with the largest specimens estimated as being 9.7 metres (32 ft) long. Relative to the large and powerful hindlimbs, its three-fingered forelimbs were small, and the body was balanced by a long and heavily muscled tail. It is classified as an allosaurid, a type of carnosaurian theropod dinosaur. The genus has a complicated taxonomy, and includes at least three valid species, the best known of which is A. fragilis. The bulk of Allosaurus remains have come from North America's Morrison Formation, with material also known from Portugal. It was known for over half of the 20th century as Antrodemus, but a study of the abundant remains from the Cleveland-Lloyd Dinosaur Quarry brought the name "Allosaurus" back to prominence and established it as one of the best-known dinosaurs. As the most abundant large predator in the Morrison Formation, Allosaurus was at the top of the food chain, probably preying on contemporaneous large herbivorous dinosaurs, and perhaps other predators. Potential prey included ornithopods, stegosaurids, and sauropods. Some paleontologists interpret Allosaurus as having had cooperative social behavior, and hunting in packs, while others believe individuals may have been aggressive toward each other, and that congregations of this genus are the result of lone individuals feeding on the same carcasses.
  • 2.8K
  • 16 Nov 2022
Topic Review
List of Highest Mountains on Earth
There are at least 108 mountains on Earth with elevations of 7,200 metres (23,622 ft) or greater above sea level. The vast majority of these mountains are located on the edge of the Indian and Eurasian plate- namely, in China , Pakistan , Nepal and India .
  • 2.7K
  • 10 Nov 2022
Topic Review
Irritator
Irritator is a genus of spinosaurid dinosaur that lived in what is now Brazil during the Albian stage of the Early Cretaceous Period, about 113 to 110 million years ago. It is known from a nearly complete skull found in the Romualdo Formation of the Araripe Basin. Fossil dealers had acquired this skull and sold it to the State Museum of Natural History Stuttgart. In 1996, the specimen became the holotype of the type species Irritator challengeri. The genus name comes from the word "irritation", reflecting the feelings of paleontologists who found the skull had been heavily damaged and altered by the collectors. The species name is a homage to the fictional character Professor Challenger from Arthur Conan Doyle's novels. Some paleontologists regard Angaturama limai—known from a snout tip that was described later in 1996—as a potential junior synonym of Irritator. Both animals hail from the same stratigraphic units of the Araripe Basin. It was also previously proposed that Irritator and Angaturama's skull parts belonged to the same specimen. Although this has been cast into doubt, more overlapping fossil material is needed to confirm whether they are the same animal or not. Other spinosaurid skeletal material, some of which could belong to Irritator or Angaturama, was retrieved from the Romualdo Formation, allowing for a replica skeleton to be made and mounted for display at the National Museum of Rio de Janeiro in 2009. Estimated at between 6 and 8 meters (20 and 26 ft) in length, Irritator weighed around 1 tonne (1.1 short tons), making it one of the smallest spinosaurids known. Its long, shallow and slender snout was lined with straight and unserrated conical teeth. Lengthwise atop the head ran a thin sagittal crest, to which powerful neck muscles were likely anchored. The nostrils were positioned far back from the tip of the snout, and a rigid secondary palate on the roof of the mouth would have strengthened the jaw when feeding. Belonging to a subadult, Irritator challengeri's holotype remains the most completely preserved spinosaurid skull yet found. The Angaturama snout tip expanded to the sides in a rosette-like shape, bearing long teeth and an unusually tall crest. One possible skeleton indicates it, like other spinosaurids, had enlarged first-finger claws and a sail running down its back. Irritator had been mistaken initially for a pterosaur, and later a maniraptoran dinosaur. In 1996, the animal was identified as a spinosaurid theropod. The holotype skull was thoroughly prepared before being redescribed in 2002, confirming this classification. Both Irritator and Angaturama belong to the Spinosaurinae subfamily. A generalist diet—like that of today's crocodilians—has been suggested; Irritator might have preyed mainly on fish and any other small prey animals it could catch. Fossil evidence is known of an individual that ate a pterosaur, either from hunting or scavenging it. Irritator may have had semiaquatic habits, and inhabited the tropical environment of a coastal lagoon surrounded by dry regions. It coexisted with other carnivorous theropods as well as turtles, crocodyliforms, and a large number of pterosaur and fish species.
  • 2.2K
  • 03 Nov 2022
Topic Review
Climate Change Education in Finland
The climate change education (CCE) is understood as a component of environmental education and education for sustainable development. Its core concept is CC literacy, which means that students understand the scientific concepts related to CC and the relationships between them, as well as the effects of CC and their own activities on the environment. CCE is multidisciplinary and interdisciplinary. Multidisciplinarity means that knowledge of various individual sciences is needed. Interdisciplinarity, on the other hand, incorporates elements from a variety of disciplines and also integrates environmental, economic, social and political issues.
  • 2.2K
  • 30 Mar 2022
Topic Review
Tools for Shoreline Change Analysis and Detection
A shoreline is the point of the physical border between land and water. While this definition looks simple, it is indeed challenging in its practical application. The position of the shoreline changes through time due to cross-shore and alongshore sediment movement in the littoral zone, and through changes in water levels. Shoreline change analysis and detection studies have progressed from using simple observation (description) from historical maps and topographical maps to employing high-resolution multi-temporal satellite images with remote sensing and Geographic Information System (GIS) approaches for a better understanding of the subject.
  • 2.0K
  • 05 May 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.
  • 1.9K
  • 18 Oct 2022
Topic Review
Geoheritage
“Geoheritage” is a new term that assumes complete perception of Man for nature and the environment. As stated by McBriar “Geological-geomorphological heritage is the collection of geotopes, deposits, forms, and processes that comprise the geological history of each region, and the concept of preserving geological-geomorphological heritage is a cultural concept”.
  • 1.9K
  • 23 Sep 2021
Topic Review
Calcareous Tufa
The term calcareous tufa, or freshwater travertine, is widely used in the scientific literature to describe carbonate deposits precipitated from cool groundwaters of meteoric origin enriched in CO2 (carbon dioxide) by percolating through organic soils.
  • 1.7K
  • 11 May 2023
Topic Review
3D City Models
3D city models are digital models of urban areas that represent terrain surfaces, sites, buildings, vegetation, infrastructure and landscape elements in three-dimensional scale as well as related objects (e.g., city furniture) belonging to urban areas. Their components are described and represented by corresponding two-dimensional and three-dimensional spatial data and geo-referenced data. 3D city models support presentation, exploration, analysis, and management tasks in a large number of different application domains. In particular, 3D city models allow "for visually integrating heterogeneous geoinformation within a single framework and, therefore, create and manage complex urban information spaces."
  • 1.5K
  • 04 Nov 2022
Topic Review
Eurypterus
Eurypterus (/jʊəˈrɪptərəs/ yoo-RIP-tər-əs) is an extinct genus of eurypterid, a group of organisms commonly called "sea scorpions". The genus lived during the Silurian period, from around 432 to 418 million years ago. Eurypterus is by far the most well-studied and well-known eurypterid. Eurypterus fossil specimens probably represent more than 95% of all known eurypterid specimens. There are fifteen species belonging to the genus Eurypterus, the most common of which is E. remipes, the first eurypterid fossil discovered and the state fossil of New York. Members of Eurypterus averaged at about 13 to 23 cm (5 to 9 in) in length, but the largest individual discovered was estimated to be 60 cm (24 in) long. They all possessed spine-bearing appendages and a large paddle they used for swimming. They were generalist species, equally likely to engage in predation or scavenging.
  • 1.5K
  • 09 Nov 2022
Topic Review
Thalassocnus
Thalassocnus is an extinct genus of semiaquatic ground sloths from the Miocene and Pliocene of the Pacific South American coast. It is monotypic within the subfamily Thalassocninae. The five species—T. antiquus, T. natans, T. littoralis, T. carolomartini, and T. yuacensis—represent a chronospecies, a population gradually adapting to marine life in one direct lineage. They are the only known aquatic sloths. They have been found in the Pisco Formation of Peru and the Bahía Inglesa, Coquimbo, and Horcón formations of Chile. Thalassocninae has been placed in both the families Megatheriidae and Nothrotheriidae. Thalassocnus evolved several marine adaptations over the course of 4 million years, such as dense and heavy bones to counteract buoyancy, the internal nostrils migrating farther into the head to help with breathing while completely submerged, the snout becoming wider and more elongated to consume aquatic plants better, and the head angling farther and farther downwards to aid in bottom feeding. The long tail was probably used for diving and balance similarly to the modern day beaver (Castor spp.) and platypus (Ornithorhynchus anatinus). Thalassocnus probably walked across the seafloor and dug up food with its claws. They probably could not do high-powered swimming, relying on paddling if necessary. Early Thalassocnus were probably generalist grazers eating seaweed and seagrasses close to shore, whereas later species specialized on seagrasses farther off the coast. They were probably preyed upon by sharks and macroraptorial sperm whales such as Acrophyseter. Thalassocnus were found in formations with large marine mammal and shark assemblages.
  • 1.4K
  • 27 Sep 2022
Topic Review
List of Paleobiota of the Morrison Formation
The Morrison Formation is a distinctive sequence of Late Jurassic sedimentary rock that is found in the western United States, which has a wide assortment of taxa represented in its fossil record, including dinosaur fossils in North America. It is composed of mudstone, sandstone, siltstone and limestone and is light grey, greenish gray, or red. Most of the fossils occur in the green siltstone beds and lower sandstones, relics of the rivers and floodplains of the Jurassic period. (mostly from Foster ; the higher-level classifications will vary as new finds are made.
  • 1.4K
  • 09 Nov 2022
Topic Review
GeoAI in Integrated Hydrological and Fluvial Systems Modeling
Geospatial artificial intelligence (GeoAI) allows the harnessing of big and high-dimensional data to better understand the hydrological processes in a particular system. Specifically, GeoAI provides new data analytic tools to the entire data processing cycle, such as sensor data fusion, hydrological modeling, data assimilation, multi-objective scenario optimization, smart decision support, evaluation of climate change impact, construction of early warning systems, and geo-visualization. 
  • 1.4K
  • 22 Jul 2022
Topic Review
Miragaia Longicollum
Miragaia (named after Miragaia, the parish in Portugal and geologic unit where its remains were found) is a long-necked stegosaurid dinosaur. Its fossils have been found in Upper Jurassic rocks in Portugal (Lourinhã Formation, Sobral Unit) and possibly also Wyoming, United States (Morrison Formation). Miragaia has the longest neck known for any stegosaurian, which included at least seventeen vertebrae.
  • 1.3K
  • 14 Nov 2022
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