FUTURE OF THE PLANET WITH GLOBAL WARMING Almost all scientists believe that global warming has a great impact on the earth itself as well as on the human race. It is largely caused by an increase in greenhouse gases because of human activity. While global warming can occur for other reasons, most believe that climate change is happening from the activities of humans. Things that have already occurred are changes in season timing, glacial retreat, rising seawater, and extreme weather events. Climate change can occur because of sunspot activity, changes in the sun s output, or human activities. The temperature has clearly begun to rise as part of human activity in the last 100 years. This is largely due to an increase in greenhouse gases. Temperatures may rise in the 21st century to the same levels as existed 3 million years ago, in the Pliocene era. There are several indicators that change in a world that is warming. Increasing parameters are air surface temperature, humidity, ocean air temperature, sea surface temperature, sea level, land temperature, and ocean heat contact. Decreasing parameters are sea ice levels, snow cover, and glacier size. Biological systems have also changed, including the migration of flora and fauna to areas near the poles. The main greenhouse gases are methane, carbon dioxide, and nitrous oxide, which are increasing in concentration. With global warming, there is an increase in extreme weather events, particularly increases in heavy precipitation events. There will be a reduction in subtropical rainfall with increases in equatorial and subpolar precipitation. Dry regions will be drier and wet regions will be wetter. It isn t yet clear if tropical cyclones and flooding has been on the rise since global warming has started. Warm weather records are twice as likely to be broken as cold ones. In the far future, there will be more very hot days and fewer very cold days. The frequency of cyclones will stay unchanged but their severity will increase. The cryosphere or areas covered by snow and ice has diminished and will continue to diminish. Arctic sea ice may be lost altogether by 2100 CE. Snowpack in North America will decline and the loss of glaciers and snow in Greenland and Antarctica will cause sea level rise. Seasonal activities in winter and water supply from glaciers and snowpack will decrease. Oceans are a sink for carbon dioxide. Increases in carbon dioxide level will acidify the oceans so they cannot absorb any more. Oceans will not be able to absorb any more heat from the atmosphere, which can deplete oxygen from the ocean, affecting ocean life. Sea level rises will threaten coastal areas. The rise in sea level is from global expansion and the melting of glaciers and ice sheets. Thermal expansion takes on the greatest role in sea level rise so far.
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