a set of physical conditions of the lower atmosphere such as temperature, precipitation, humidity, wind speed, cloud cover, and other factors in a given area over a period of hours or days.
an area's general pattern of atmospheric conditions over periods of at least 3 decades and up to thousands of years.
major surface winds that blow almost continuously and help to distribute heat and moisture over the earth's surface and drive ocean currents.
a tropical atmospheric circulation that is defined by the average over longitude, which features rising motion near the equator, poleward flow 10-15 kilometers above the surface, descending motion in the subtropics, and equatorward flow near the surface. This circulation is intimately related to the trade winds, tropical rainbelts, subtropical deserts and the jet streams.
mass movements of surface water created by prevailing winds blowing over the oceans.
El Nino Southern Oscillation or ENSO
Part of the broader Southern Oscillation climate pattern. It is the WARM phase. Where a warm water pool approaches South American coast. Absence of cold upwelling increases warming.
Part of the broader Southern Oscillation climate pattern. It is the COLD phase. Warm water is farther west than usual. During this period, the sea surface temperature across the equatorial Eastern Central Pacific Ocean will be lower than normal by 3-5 °C.
small amounts of several gases in the atmosphere, including water vapor, CO2, CH4, and N2O absorb and release heat that warms the atmosphere, thus playing a role in determining the earth's average temperatures and its climates.
natural greenhouse effect
natural warming of the troposphere due to heat absorbing molecules that emit longer-wavelength IR that warms the atmosphere.
rain shadow effect
a dry area on the leeward side of a mountainous area because the mountains block the passage of rain-producing weather systems casting a dryness behind them.
large terrestrial regions, each characterized by certain types of climate and dominant plant life.
a biome where annual precipitation is low and often scattered unevenly throughout the year.
a type of desert such as the Sahara and the Namib of Africa that are hot and dry most of the year.
a type of desert such as the Sonoran Desert of CA/SW AZ/Mexico where daytime temperatures are high in summer and low in winter and there is more precipitation than in tropical deserts.
a type of desert such as the Gobi in Mongolia, where vegetation is sparse, winters are cold, summers are warm or hot, and precipitation is low.
biomes that occur mostly in the interiors of continents in areas that are too moist for deserts to form and too dry for forests to grow.
tropical grassland or savanna
a type of grassland that contains widely scattered clumps of trees, has warm temperatures year-round and alternating dry and wet seasons. Many found in East Africa.
temperate grassland or prairies
a type of grassland where winters can be bitterly cold, summers are dry and hot, and annual precipitation is fairly sparse and falls unevenly throughout the year. Many found in mid to western parts of the U.S. and Canada.
cold grasslands or arctic tundra
a type of grassland that lie south of the arctic polar ice cap. These treeless plains are bitterly cold, swept by frigid winds, and covered with ice and snow. They also have permafrost.
underground soil in which captured water stays frozen for more than 2 consecutive years.
temperate shrubland or chaparral
found in coastal regions that border on deserts that consist mostly of dense growths of low-growing evergreen shrubs and occasional small trees with leathery leaves that reduce evaporation.
tropical rain forests
a type of forest that are found near the equator where hot, moisture-laden air rises and dumps its moisture. They are dominated by broadleaf evergreen plants and have a high degree of biodiversity, but nutrient poor soils.
broadleaf evergreen plants
plants which keep most of their leaves year-round.
emergent layer of tropical rainforests
This layer of a tropical rainforest contains a small number of very large trees , which grow above the general canopy, reaching heights of 45-55 m. They need to be able to withstand the hot temperatures and strong winds that occur above the canopy in some areas. Eagles, butterflies, bats and certain monkeys inhabit this layer.
canopy layer of tropical rainforests
This layer of a rainforest contains the majority of the largest trees, typically 30-45 m tall. The densest areas of biodiversity are found here, a more or less continuous cover of foliage formed by adjacent treetops. It is home to 50 percent of all plant species, suggesting that perhaps half of all life on Earth could be found there. Epiphytic plants attach to trunks and branches, and obtain water and minerals from rain and debris that collects on the supporting plants. The fauna is similar to that found in the emergent layer, but more diverse. A quarter of all insect species are believed to exist in this layer.
understory layer of tropical rainforests
This layer lies between the canopy and the forest floor. It is home to a number of birds, snakes and lizards, as well as predators such as jaguars, boa constrictors and leopards. The leaves are much larger at this level. Insect life is also abundant. Only about 5% of the sunlight shining on the rainforest canopy reaches this layer.
forest floor of tropical rainforests
This is the bottom-most layer of a rainforest and receives only 2% of the sunlight. Only plants adapted to low light can grow here. It is relatively clear of vegetation because of the low sunlight penetration. It also contains decaying plant and animal matter, which disappears quickly, because the warm, humid conditions promote rapid decay. Many forms of fungi growing here help decay the animal and plant waste.
temperate deciduous forests
a type of forest that grows in areas with moderate average temperture that change significantly with the seasons. These areas have long, warm summers, cold but not too severe winters, and abundant precipitation, often spread evenly throughout the year. It is dominated by broadleaf deciduous trees that lose their leaves in the fall.
evergreen coniferous or boreal forests or tiagas
these forests are cold and found just south of the arctic tundra. The winters are long, dry, and extremely cold. Most are dominated by coniferous (cone bearing) evergreen trees that keep most of their leaves year-round.
coastal coniferous or temperate rain forests
these are forests found in scattered coastal temperate areas with ample rainfall or moisture from dense ocean fogs. Ex.: redwood forests of NW U.S. and Canada.