Climate means the usual condition of the temperature, humidity, atmospheric pressure, wind, rainfall, and other Meteorology|meteorological Weather|elements in an area of the Earth's surface for a long time. In simple terms climate is the average condition for about thirty years. Climate and weather are different. Weather is the day to day conditions in the atmosphere. The types of climates are: Tropical, Desert/dry, Temperate, Polar, Mediterranean.
The latitude, ground, and height can change the climate of a location. It is also important to note if oceans or other large bodies of water are nearby. Climates are most commonly classified by temperature and precipitation. The most commonly used classification was the Köppen climate classification, first made by Wladimir Köppen. The Thornthwaite system, which was used from 1948, not only uses temperature and precipitation information, but evapotranspiration too. This makes it useful for studying how many different kinds of animal species there are, and about the things that could happen when climates change. The Bergeron and Spatial Synoptic Classification systems focus more on where the air masses which help make climates come from.
Climates can change after a long time. Nowadays people are making the world warmer.
Fold (geology)
Rock often deforms in such a way that it bends instead of breaking. This is called a fold. The term fold is used in geology when one or a stack of originally flat, level surfaces, such as sedimentary strata, are bent or curved as a result of pressure and high temperature. The basic cause is likely to be some aspect of plate tectonics.
When two forces act towards each other from opposite sides, rock layers are bent into "folds". The process by which folds are formed due to compression is known as folding. Folding is one of the endogenetic processes; it takes place within the Earth's crust.
Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur singly as isolated folds and in extensive fold trains of different sizes, on a variety of scales. A set of folds distributed on a regional scale constitutes a "fold belt", a common feature of orogenic zones.
There are large-scale and small-scale folds. Large-scale folds are found mainly along a collision boundary between two tectonic plates.
The upfold is called an anticline. The downfold is called a syncline.
The imaginary line joining the highest points along the upfold is called the crest line.
The flanks of a fold are known as the limbs.
The central line from which the rock strata dip away in opposing directions is called the axis of fold.
According to the degree of folding of the layers, folds can be classified into five main types.
Large depressions called geosynclines form between plates. Seas filled the geosynclines and rivers flowing into them carried sediments (sand and silt) which build up on the sea bed.
Over millions of years the sediments were compressed, by their own weight, into sedimentary rocks, e.g. sandstone, limestone etc.
Large-scale folding will develop parallel ranges of round-top mountains along destructive plate boundaries. These mountains are known as fold mountains.
Examples of fold mountain ranges:
Volcanism
Volcanism (or vulcan activity) is the eruption of magma onto the surface of the Earth.
Magma under the crust is under very great pressure. When folding and faulting occur, cracks or fractures appear. These are lines of weakness.
When these lines of weakness develop downward in the crust and reach the magma, they will release the pressure in the magma. This allows magma to rise up along the lines of weakness and intrude into the crust. Some magma may even reach the Earth's surface as lava.
Volcanoes are places where magma reaches the earth's surface. The type of volcano depends on the location of the eruption and the consistency of the magma.
Intrusive volcanism is when magma is forced into the rocks that make up the Earth's crust. When it cools and become solid while still underground, different features called plutons are formed. The rock formed is intrusive igneous rock.
These plutons will be exposed at the surface of land when the overlying rocks are removed after a long time of denudation (laid bare by erosion).
Major features formed by intrusive volcanicity include: batholith, laccolith, dyke, pipe and sill.
The molten magma under great pressure forces its way through the fissure of underground rocks and reaches the Earth's surface to form "igneous extrusion".
Major extruded materials include gas, liquid and solid.
Features formed are:
Pacific Ocean
The Pacific Ocean is the body of water between Asia and Australia in the west, the Americas in the east, the Southern Ocean to the south, and the Arctic Ocean to the north. It is the largest named ocean and it covers one-third of the surface of the entire world. It joins the Atlantic Ocean at a line drawn south from Cape Horn, Chile/Argentina to Antarctica, and joins the Indian Ocean at a line drawn south from Tasmania, Australia to Antarctica.
As the Atlantic slowly gets wider, the Pacific is slowly shrinking. It does this by folding the sea floor in towards the centre of the Earth - this is called subduction. This bumping and grinding is hard so there are many earthquakes and volcanoes when the pressure builds up and is quickly released as large explosions of hot rocks and dust. When an earthquake happens under the sea, the quick jerk causes a tsunami. This is why tsunamis are more common around the edge of the Pacific than anywhere else. Many of the Earth's volcanoes are either islands in the Pacific, or are on continents within a few hundred kilometers of the ocean's edge. Plate tectonics are another reason which makes Pacific Ocean smaller.
Antarctica
Antarctica is the Earth's southernmost continent. It is on the South Pole. It is almost entirely south of the Antarctic Circle. Around Antarctica is the Southern Ocean. It is the fifth-largest continent in area after Asia, Africa, North America, and South America. About 99% of Antarctica is covered by ice. This ice averages at least 1.6 kilometers (1.0 miles) thick.
Antarctica is the coldest, driest and windiest continent. It is also, on average, the highest of all the continents. Antarctica is considered a desert. It has yearly precipitation of only 200 mm (8 inches) near the sea and far less inland. No humans live in Antarctica permanently. However, about 1,000 to 5,000 people live through the year at the science stations in Antarctica. Only plants and animals that can live in cold live there. The animals include penguins, seals, nematodes, tardigrades and mites. Plant life includes some grass and shrubs, algae, lichen, fungi, and bacteria.
The first known sighting of the continent was in 1820. Antarctica was mostly forgotten for the rest of the 19th century. This was because of its hostile environment, few resources, and isolation. The first official use of the name "Antarctica" as a continental name in the 1890s is said to have been used by Scottish cartographer John George Bartholomew.
The Antarctic Treaty was signed in 1959 by 12 countries. More countries have signed the treaty since then. So far, 46 countries have signed the treaty. The treaty declares that military activities and mineral mining are against the law. However, it supports scientific research. It also helps the continent's ecozone. More than 4,000 scientists from different nations and different interests experiment together.
Antarctica is covered by an ice sheet about four kilometres thick. Under the ice it is mostly land, although the ice shelves are over the ocean. The Transantarctic Mountains divide the land between East Antarctica in the Eastern Hemisphere and West Antarctica in the Western Hemisphere.