Released on = January 19, 2007, 10:03 pm

Press Release Author = Global Warming Awareness2007

Industry = Education

Press Release Summary = Global warming is the observed increase in the average
temperature of the Earth's atmosphere and oceans in recent decades and its projected
continuation into the future.

Press Release Body = Global warming is the observed increase in the average
temperature of the Earth's atmosphere and oceans in recent decades and its projected
continuation into the future.

Global average near-surface atmospheric temperature rose 0.6 ± 0.2 °Celsius (1.1 ±
0.4 °Fahrenheit) in the 20th century.

The prevailing scientific opinion on climate change is that "most of the warming
observed over the last 50 years is attributable to human activities."[1] Most
national governments have signed and ratified the Kyoto Protocol aimed at combatting
global warming. (See List of Kyoto Protocol signatories.)

The main cause of the human-induced component of warming is the increased
atmospheric concentration of greenhouse gases (GHGs) such as carbon dioxide (CO2).
This leads to warming of the surface and lower atmosphere by increasing the
greenhouse effect. Greenhouse gases are released by activities such as the burning
of fossil fuels, land clearing, and agriculture.

The measure of the response to increased GHGs, and other anthropogenic and natural
climate forcings is climate sensitivity. It is found by observational and model
studies.[2] This sensitivity is usually expressed in terms of the temperature
response expected from a doubling of CO2 in the atmosphere. The current literature
estimates sensitivity in the range 1.5-4.5 °C (2.7-8.1 °F). Models referenced by the
Intergovernmental Panel on Climate Change (IPCC) predict that global temperatures
may increase by between 1.4 and 5.8 °C (2.5 to 10.5 °F) between 1990 and 2100. The
uncertainty in this range results from both the difficulty of predicting the volume
of future greenhouse gas emissions and uncertainty about climate sensitivity.

An increase in global temperatures can in turn cause other changes, including a
rising sea level and changes in the amount and pattern of precipitation. These
changes may increase the frequency and intensity of extreme weather events, such as
floods, droughts, heat waves, hurricanes, and tornados. Other consequences include
higher or lower agricultural yields, glacier retreat, reduced summer streamflows,
species extinctions and increases in the ranges of disease vectors. Warming is
expected to affect the number and magnitude of these events; however, it is
difficult to connect particular events to global warming. Although most studies
focus on the period up to 2100, warming (and sea level rise due to thermal
expansion) is expected to continue past then, since CO2 has a long average
atmospheric lifetime.

Remaining scientific uncertainties include the exact degree of climate change
expected in the future, and especially how changes will vary from region to region
across the globe. A hotly contested political and public debate has yet to be
resolved, regarding whether anything should be done, and what could be
cost-effectively done to reduce or reverse future warming, or to deal with the
expected consequences.


Web Site = http://www.globalwarmingawarenessusa.com

Contact Details = globalwa@globalwarmingawarenessusa.com