Global Warming is Happening Now
Scientists are no longer telling us what will happen, they are telling us what is happening.
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Pristine Habitat : Few places on Earth remain undisturbed by human impacts, and now as a result of global warming, even the far stretches of the Arctic Ocean are no longer safe from our reach. |
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Climate change is projected to cause northward shifts in vegetation, and because warmer temperatures favor taller, denser vegetation, boreal forests will encroach on the arctic tundra, and the tundra will shift northward into the realm of the polar desert. The consequences of such change will be varied and sometimes seemingly contradictory: tree growth rates will increase in some areas and decline in others; disturbances such as fires and floods will likely either speed up or inhibit forest growth; and although the range of trees such as black and white spruce may expand, higher temperatures and drier conditions will make them more vulnerable to disease and to insect pests such as the spruce bark beetle and the black-headed budworm, which in turn will benefit from those changing conditions.
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As a result of encroaching forests and rising sea levels, tundra area is expected to shrink to its lowest extent in at least the past 21,000 years, potentially reducing the breeding area for many migratory bird species and the grazing areas for land animals that depend on the open landscape of tundra and polar desert habitats.
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