Main articles: Polar ice packs and Climate change in the Arctic
The decline in Arctic sea ice, both in extent and thickness, over the last several decades is further evidence for rapid climate change.[60] Sea ice is frozen seawater that floats on the ocean surface. It covers millions of square miles in the polar regions, varying with the seasons. In the Arctic, some sea ice remains year after year, whereas almost all Southern Ocean or Antarctic sea ice melts away and reforms annually. Satellite observations show that Arctic sea ice is now declining at a rate of 11.5 percent per decade, relative to the 1979 to 2000 average.[61]
This video summarizes how climate change, associated with increased carbon dioxide levels, has affected plant growth.
Vegetation …show more content…
Some changes in climate may result in increased precipitation and warmth, resulting in improved plant growth and the subsequent sequestration of airborne CO2. A gradual increase in warmth in a region will lead to earlier flowering and fruiting times, driving a change in the timing of life cycles of dependent organisms. Conversely, cold will cause plant bio-cycles to lag.[62] Larger, faster or more radical changes, however, may result in vegetation stress, rapid plant loss and desertification in certain circumstances.[63][64] An example of this occurred during the Carboniferous Rainforest Collapse (CRC), an extinction event 300 million years ago. At this time vast rainforests covered the equatorial region of Europe and America. Climate change devastated these tropical rainforests, abruptly fragmenting the habitat into isolated 'islands' and causing the extinction of many plant and animal