Global warming

Consequence: ecosystem shifts and species die-off
The increase in global temperatures is expected to disrupt ecosystems and result in loss of species diversity, as species that cannot adapt die off. The first comprehensive assessment of the extinction risk from global warming found that more than one million species could be committed to extinction by 2050 if global warming pollution is not curtailed. Some ecosystems, including alpine meadows in the Rocky Mountains, as well as tropical montane and mangrove forests, are likely to disappear because new warmer local climates or coastal sea level rise will not support them.[Photo] Warmer temperatures may cause some ecosystems, including alpine meadows in the Rocky Mountains, to disappear. Warning signs today

A recent study of nearly 2,000 species of plants and animals discovered movement toward the poles at an average rate of 3.8 miles per decade. Similarly, the study found species in alpine areas to be moving vertically at a rate of 20 feet per decade in the 2nd half of the 20th century.

The latest IPCC report found that approximately 20 to 30 percent of plant and animal species assessed so far are likely to be at increased risk of extinction if global average temperature increases by more than 2.7 to 4.5 degrees Fahrenheit.

Some polar bears are drowning because they have to swim longer distances to reach ice floes. The U. S. Geological Survey has predicted that two-thirds of the world's polar bear sub-populations will be extinct by mid-century due to melting of the Arctic ice cap.

In Washington's Olympic Mountains, sub-alpine forest has invaded higher elevation alpine meadows. In Bermuda and other places, mangrove forests are being lost.

In areas of California, shoreline sea life is shifting northward, probably in response to warmer ocean and air temperatures.

Over the past 25 years, some penguin populations have shrunk by 33 percent in parts of Antarctica, due to declines in winter sea-ice habitat.

The ocean will continue to become more acidic due to carbon dioxide emissions. Because of this acidification, species with hard calcium carbonate shells are vulnerable, as are coral reefs, which are vital to ocean ecosystems. Scientists predict that a 3.6 degree Fahrenheit increase in temperature would wipe out 97 percent of the world's coral reefs