Global warming and climate change refer to an increase in average global temperatures. Natural events and human activities are believed to be contributing to an increase in average global temperatures. This is caused primarily by increases in “greenhouse” gases such as Carbon Dioxide (CO2). A warming planet thus leads to a change in climate which can affect weather in various ways. What are the main indicators of Climate Change?
As explained by the US agency, the National Oceanic and Atmospheric Administration (NOAA), there are 7 indicators that would be expected to increase in a warming world (and they are), and 3 indicators would be expected to decrease (and they are):
Ten indicators for a warming world, Past Decade Warmest on Record According to Scientists in 48 Countries, NOAA, July 28, 2010
What is the Greenhouse Effect?
The term greenhouse is used in conjunction with the phenomenon known as the greenhouse effect. * Energy from the sun drives the earth’s weather and climate, and heats the earth’s surface; * In turn, the earth radiates energy back into space;
* Some atmospheric gases (water vapor, carbon dioxide, and other gases) trap some of the outgoing energy, retaining heat somewhat like the glass panels of a greenhouse; * These gases are therefore known as greenhouse gases;
* The greenhouse effect is the rise in temperature on Earth as certain gases in the atmosphere trap energy.
Six main greenhouse gases are carbon dioxide (CO2), methane (CH4) (which is 20 times as potent a greenhouse gas as carbon dioxide) and nitrous oxide (N2O), plus three fluorinated industrial gases: hydro fluorocarbons (HFCs), per fluorocarbons (PFCs) and sulphur hexafluoride (SF6). Water vapor is also considered a greenhouse gas.
This graph, based on the comparison of atmospheric samples contained in ice cores and more recent direct measurements, provides evidence that atmospheric CO2 has increased since the...