Global warming effects

Source 1:Some impacts from increasing temperatures are already happening.

• Ice is melting worldwide, especially at the Earth’s poles. This includes mountain glaciers, ice sheets covering West Antarctica and Greenland, and Arctic sea ice.
• Researcher Bill Fraser has tracked the decline of the Adélie penguins on Antarctica, where their numbers have fallen from 32,000 breeding pairs to 11,000 in 30 years.
• Sea level rise became faster over the last century.
• Some butterflies, foxes, and alpine plants have moved farther north or to higher, cooler areas.
• Precipitation (rain and snowfall) has increased across the globe, on average.
• Spruce bark beetles have boomed in Alaska thanks to 20 years of warm summers. The insects have chewed up 4 million acres of spruce trees

Author: national geographic

Website:http://environment.nationalgeographic.com/environment/global-warming/gw-effects/

Date:2007

Source 2: A large fraction of plant and animal species are likely to be at an increased risk of extinction if global average surface temperatures rise another 1.5 to 2.5 °C (2.7 to 4.5 °F) by the year 2100. Species loss estimates climb to as much as 40 percent for a warming in excess of 4.5 °C (8.1 °F)—a level that could be reached in the IPCC’s higher emissions scenarios. A 40 percent extinction rate would likely lead to major changes in the food webs within ecosystems and have a destructive impact on ecosystem function
Author:Henrik Selin
http://global.britannica.com/EBchecked/topic/235402/global-warming/274853/Environmental-consequences-of-global-warming. Date:Avaliable 3 of September of 2014

Source 3:Most scientists recognize that global warming does seem to be happening, but a few don't believe that it is anything to be worried about. These scientists say that the Earth is more resistant to climate changes on this scale than we think. Plants and animals will adapt to subtle shifts in weather patterns, and it is unlikely anything catastrophic will happen as a result of global warming. Slightly longer growing seasons, changes in precipitation levels and stronger weather, in their opinion, are not generally disastrous. They also argue that the economic damage caused by cutting down on the emission of greenhouse gases will be far more damaging to humans than any of the effects of global warming.
Author: Jonathan Strickland and Ed Grabianowski

Website: http://science.howstuffworks.com/environmental/green-science/global-warming7.htm

Date: Avaliable 4 of September