Global Climate ChangeIntroduction:Climate change is a lasting change in weather patterns around average conditions. Some factors like global warming, greenhouse effect and biotic processes are some of the reasons for global climate change. Global average temperatures have changed, as have precipitation patterns. Over the past century, human activities have led to increased emissions of heat-trapping gases like carbon dioxide. The Earth's average temperature has increased by 1.4°F, and it is also expected to increase further by about 2°F to 13.5°F in the coming decades. Significant, and potentially significant, changes in weather and climate conditions could result from weak average weather conditions. Many places have experienced changes in the form of floods, intense rains, frequent heat waves, droughts and poor distribution of precipitation. These climate changes have also had an impact on the oceans and glaciers. Glaciers are melting, causing sea levels to rise and oceans to become more acidic. These climate changes will pose more challenges to our environment. Greenhouse effect and greenhouse gases: The Earth absorbs a lot of energy from the sun and heats up during the day. It cools by releasing infrared radiation. But greenhouse gases don't let infrared radiation escape into space. This trapping of long-wavelength infrared radiation results in higher temperature and more heat on the Earth's surface. Over the past decades, human activities have tended to release many greenhouse gases into the atmosphere, such as carbon dioxide (Co2), methane, carbon monoxide, nitrous oxide, carbon tetrafluoride carbon and hexafluoroethane. Most of these greenhouse gases come from deforestation of the Arctic sea cap and increased thawing of glaciers in Greenland and Antarctica, as well as earlier flowering of trees and plants in spring. Earth's temperature measurements show surface warming that corresponds to warming of the troposphere and cooling of the stratosphere. This trend is consistent with global climate change and also with the depletion of the ozone layer in the stratosphere. There is also the possibility of greater climate change than current scenarios and satellite records predict. The occurrence of unanticipated climate change increases as human disruption of the climate system increases. References: http://www.epa.gov/climatechange/basics/http://www.epa.gov/climatechange/science/causes . htmlhttp://downloads.globalchange.gov/usimpacts/pdfs/Global.pdfhttp://www.ucar.edu/learn/1_4_1.htmhttp://hyperphysics.phy-astr.gsu.edu/hbase/thermo/grnhse. HTML