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Polar Forests Of The Cretaceous
Cretaceous polar forests were temperate forests that grew at polar latitudes during the final period of the Mesozoic Era, known as the Cretaceous Period 145–66 Ma. During this period, global average temperature was about higher and carbon dioxide (CO2) levels were approximately 1000 parts per million (ppm), 2.5 times the current concentration in Earth's atmosphere. The abundance of atmospheric carbon dioxide had a very significant impact on global climate and Earth's natural systems as its concentration is considered one of the main factors in the development of a pronounced greenhouse Earth during the Cretaceous, with a very low average global temperature gradient. As a consequence, high paleolatitudes in both hemispheres were much warmer than at present. This temperature gradient was partly responsible for the lack of continental ice sheets in polar regions. As a response to elevated global temperatures, the Earth's hydrologic cycle was significantly enhanced due to greate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Temperate Forest
A temperate forest is a forest found between the tropical and boreal regions, located in the temperate zone. It is the second largest terrestrial biome, covering 25% of the world's forest area, only behind the boreal forest, which covers about 33%. These forests cover both hemispheres at latitudes ranging from 25 to 50 degrees, wrapping the planet in a belt similar to that of the boreal forest. Due to its large size spanning several continents, there are several main types: deciduous, coniferous, mixed forest, and rainforest. Climate The climate of a temperate forest is highly variable depending on the location of the forest. For example, Los Angeles and Vancouver, Canada are both considered to be located in a temperate zone, however, Vancouver is located in a temperate rainforest, while Los Angeles is a relatively dry subtropical climate. Types of temperate forest Deciduous They are found in Europe, East Asia, North America, and in some parts of South America. Deciduous fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Fern
The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissues that conduct water and nutrients, and in having life cycles in which the branched sporophyte is the dominant phase. Ferns have complex leaf, leaves called megaphylls that are more complex than the microphylls of clubmosses. Most ferns are leptosporangiate ferns. They produce coiled Fiddlehead fern, fiddleheads that uncoil and expand into fronds. The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the Polypodiopsida, comprising both the leptosporangiate (Polypodiidae (plant), Polypodiidae) and eusporangiate ferns, the latter group including horsetails, Psilotaceae, whisk ferns, marattioid ferns, and ophioglossoid ferns. The fern crown group, consisting of the leptosporangiates and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Paleoclimate
Paleoclimatology ( British spelling, palaeoclimatology) is the scientific study of climates predating the invention of meteorological instruments, when no direct measurement data were available. As instrumental records only span a tiny part of Earth's history, the reconstruction of ancient climate is important to understand natural variation and the evolution of the current climate. Paleoclimatology uses a variety of proxy methods from Earth and life sciences to obtain data previously preserved within rocks, sediments, boreholes, ice sheets, tree rings, corals, shells, and microfossils. Combined with techniques to date the proxies, the paleoclimate records are used to determine the past states of Earth's atmosphere. The scientific field of paleoclimatology came to maturity in the 20th century. Notable periods studied by paleoclimatologists include the frequent glaciations that Earth has undergone, rapid cooling events like the Younger Dryas, and the rapid warming durin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Mount Glossopteris
The Ohio Range () is a range in the Transantarctic Mountains of Antarctica. It is about long and wide, extending west-southwest – east-northeast from Eldridge Peak to Mirsky Ledge. The range forms the northeast end of the Horlick Mountains and consists primarily of a large snow-topped plateau with steep northern cliffs and several flat-topped ridges and mountains. The highest point, , is the summit of Mount Schopf. Exploration and naming The range was surveyed in 1958–59 by the United States Antarctic Research Program (USARP) Horlick Mountains Traverse. In October 1958 William E. Long (for whom the Long Hills are named) made a round trip by air from the Byrd Station in West Antarctica over the Wisconsin Range, Ohio Range, Thiel Mountains and Whitmore Mountains. Long noted that the Ohio Range has a thick layer of stratified rocks. Later a tractor train visited the base of Mount Glossopteris, where four of the party climbed the mountain and collected samples of rock and fos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
