Changing Global Land Surface

Plants on the Move
A changing climate could cause some migration of plant biomes. For example, under a warming climate we might expect the northern boreal forests in Canada, Alaska and Siberia to creep northwards and replace the treeless tundra. This migration would be associated with changes in evapotranspiration, changes in how much sunlight is reflected by the surface, and changes in "aerodynamic roughness" (which refers to the fact that different vegetation types have varying effects on wind patterns)-all of which will directly impact the local climate.

There is also anthropogenic (human-induced) interaction with plant biomes. Humankind has already set in place vast areas of cropland in the mid-latitudes, and deforestation continues in the tropics as developing nations try to provide for their populations. While these anthropogenic changes in the biomes are significant, especially with regard to species diversity, it is likely that they play less critical roles in the carbon cycle and global climate. But, monitoring these changes to the biosphere is vital to our understanding of how humans may be affecting other species on this planet.

Snow and Ice

In addition to land vegetation, other surface features are expected to change that require continuous monitoring from orbit. Snow and ice are critical players in determining high-latitude climates as many increased-carbon dioxide climate simulations predict a large-scale retreat of glaciers and permanent land ice, as well as a reduction in Northern Hemisphere snowfall. Changes in snow and ice cover can have profound effects on the climate system, as snow and ice reflect most of the incoming solar radiation. Thus, their replacement by dark vegetation or bare rock would act to reinforce a warming trend.

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Changing Global Land Surface
The Carbon Cycle
Greenhouse Warming
Plants, Snow & Ice
Terra & Landsat Observations
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