Problem

Science

• We have had 27 consecutive years with the global average temperature greater than the 120 year historical average.
• The polar ice caps are melting.
• The four highest average world temperature years all occured within the last 6 years:
  1. 1998 58.17°
  2. 2002
  3. 2003
  4. 2001
• In 2003 Glaciers in Argentina and Chile are melting at double the rate of 1975
• Ice shelves the size of Rhode Island have broken off of Antartica since 1995.
• The Intergovernmental Panel on Climate Change's (IPCC) Fourth Assessment Report in 2007 states that the probability of human influence on Climate Change is over 90%.
• Temperatures are rising 3 times as fast ofer the last three decades as it did over the entire 20th century.

Some of their arguments:
Warming is part of a natural cycle:
There are hisorical cycles of warming and cooling (e.g. an ice age every 100,000 years):
However, the current rate of change (1°F in the northern hemisphere in the last 50 years) is much greater than any in the last 500 (some say 1,300) years.

There are several theories for these natural cycles:
One the earth's orbit is not round and we get closer to the sun every so often.
And the suns output increases every 11 years or so. However the change in solar radiation has only benn about 0.1% over the last 50 years which would not account for magnitude of the warming.
Also, the lower atmosphere (troposphere) is warming while the upper atmosphere (stratosphere) is cooler. If the sun was causing the warming both would be getting warmer.

Intresting Plots

Al Gore shows a similar chart to the above in his 2006 movie "An Inconvenient Truth".

I don't know why they use this chart because it seems to indicate there are natural cycles way before our current increase in greenhouse gas emissions and CO₂ increases seem to lag the warming.
One explanation is the time resolution of these two records is too low to provide a accurate comparison.
Another explanation at RealClimate.org says "The CO₂ does not initiate the warmings, but acts as an amplifier once they are underway. CO2 might be stored in the deep ocean during ice ages, and then get released through natural ocean currents when the climate warms."

1,000 yrs:

Source: http://www.manicore.com/anglais/documentation_a/greenhouse/rise_start.html

80 yrs:

Source: www.climatechange.govt.nz

Sources of CO₂ and greenhouse gasses

Politics

Solutions

Slow Population Growth:
The world population has grown from 2.5 Billion in 1950 to 6.1 Billion in 2000 and is expected to reach 9.2 Billion by 2050, 50% growth. Europe and Japan will have negative growth (due primairly to lower fertility rates) over the next 50 years. China will have a growth rate of 11%, the U.S. will grow by 41%, India by 58%, Nigeria at 131% and Pakistan at 102%.
See Top 10 countries for growth.
Recent data shows that fertility (average number of children per woman is dropping faster than expected in developing countries. This has been attributed to better education and women having more choice rather than government policy.

See: World Population

A Friday October 17, 2003 article in The Guardian "Warming doubles glacier melt" said:

Glaciers in Argentina and Chile are melting at double the rate of 1975 because of global warming scientists said yesterday, after calculating that the ice lost between 1995 and 2000 was equivalent to a rise in sea level of about 0.105mm a year.

Scientists combined space observation and survey data of the 63 largest Patagonian ice fields. Comparing ice loss rates from 1968-1975 and 1975-2000 they found it had more than doubled.

The researchers, led by Eric Rignot, from the Jet Propulsion Laboratory in Pasadena, California, wrote in the journal Science that the Patagonian glaciers accounted for 9% of the glacial contribution to sea level rises, while those in Alaska were behind sea level rises of 30%. Yet in Patagonian the area covered by glaciers was five times smaller than that in Alaska.

The greater "vulnerability" of Patagonia to climate change was due to the glaciers' higher turnover rates and a "dominance of calving glaciers".

Solutions: (pros and cons)
Sequestration - burying the CO₂

Terms:
  * Anthropogenic - derived from human activities.
  * Carbon sequestration - the process through which plant life removes CO2 from the atmosphere and stores it in biomass.
  * Geologic sequestration - a chain of activities that result in collection and transport of concentrated CO₂ gas from large emission sources, such as power plants, and subsequent injection into deep underground reservoirs.
Related Issues:
Global warming was blamed on the increase in hurricanes in 2005, but 2006 and 2007 have had a below average number of hurricane.

links:
Green Living (Cool Cities, Green Buildings)
Energy Statistics
National Climatic Data Center - NCDC Climate Monitoring at NOAA
Greenhouse Gases, Climate Change, and Energy at the Dept. of Energy (DOE)
Sources of Carbon Dioxide, 1997 from the EPA
Emissions of Greenhouse Gases in the United States 2005
United Nations Framework Convention on Climate Change (UNFCCC)
Greenhouse gas at Wikipedia
Climatology; Ice Ages at U. Oregon
Global Warming and Clean Energy at the National Sierra Club
TEN POPULAR MYTHS About Global Climate Change at the Sierra Club of Canada
WorldViewOfGlobalWarming.org - The World View of Global Warming project is documenting this change through science photography from the Arctic to Antarctica, from glaciers to the oceans, across all climate zones.
Global Warming page at Raritan Valley Sierra Club
Skeptics at the above page.
Global Warming Center at AccuWeather.com