Global Warming is often described with the more neutral sounding phrase Global Climate Change or simply Climate Change. This is, in part, because mere "warming" did not succeed in convincing the public of climate changes predicted by a number of scientists to occur, such as increases in frequency and severity of tropical storms, a possible alteration of ocean circulation leading to drastically changed (though not necessarily warmed) local climates, and so on. And while most models predict a net warming of Earth's climate, it's not uniform and there are smaller areas of cooling (e.g., most of Antarctica, along with the far northeast North America and the north Atlantic).
Global warming has become a major concern of humanity since the middle of the 20th century. It was namely then that the first increase in the Earth’s temperature was registered. The temperature became less than one degree higher, but just think of what it means on a global scale.
Greenhouse gases are compounds in the atmosphere whose odd number of atoms enable them to absorb infrared radiation (heat). Natural examples include H2O (water vapor), CO2, CH4, N2O, and O3. Their presence in the atmosphere is essential for most life as we know it; without them, Earth's temperature would be well below freezing.
In the past century, human activities have greatly increased the concentrations of all these gases (except H2O, but we'll come back to that) in the atmosphere through industrial, transportation and agricultural activities and urbanization, and added a new class as well: the Chlorofluorocarbons, or CFCs. These increases appear to have gradually increased the temperature of the Earth over the past century. The concern is that further large increases of these gases will translate into potentially damaging changes in climate. Though few believe that these will result in a "runaway" greenhouse effect leading to the hell hole conditions found on Venus, positive feedbacks (e.g., through water evaporation) do exist and are of concern. Continued emissions threaten to melt polar ice caps, cause mass ecological disruption on Earth, and destabilize some economic systems.
The science of Global Climate Change is complex. The evidence that human activities are the primary reason for global climate change is disputed. It is acknowledged, however, the planet's climate is changing and evidence may point to increased levels of greenhouse gases.. The uncertainty is to what extent the increases in greenhouse gas concentrations are responsible for climate changes over and above natural variations in climate. The sources of that uncertainty are manifold, but include whether (for example) increasing cloud cover will result in more warming (through trapping heat) or more cooling (from reflecting more light). In a series of widely and carefully reviewed reports produced by the UN's Intergovernmental Panel on Climate Change (IPCC), a broad consensus of climate scientists concluded that human activities, through changes in greenhouse gas concentrations and other effects, are having a discernible effect on global climate. There is mounting evidence that the effect is not only discernible but important.
The Kyoto Protocol, the first attempt to slow the progress of global climate change through limiting CO2 emissions, was initialed by President Clinton in 1998. However, the United States has refused to ratify the treaty, starting with the Republican-dominated Senate during the Clinton presidency and continuing through the Bush administration. This was due to three objections: First, the Bush Administration and its allies in Congress do not accept the scientific consensus that human activities play an important role in global climate change; second, they object that developing economies, such as that of China, would not be subject to the CO2 emissions caps; and third, they believe that adapting to climate change would be less expensive than attempting to mitigate it.
Supporters of the Kyoto Protocol argued that it was a first step, not the final solution to global climate change; that moderate actions now would be more effective and less expensive than more drastic actions later; and that economic calculations of adaptation vs. mitigation have not included important non-economic values compromised by unmitigated climate change.
On August 31, 2006, the California leaders of both political parties agreed to terms in the California Global Warming Solutions Act. When this legislation goes into effect it will limit the state’s global warming emissions to 1990 levels by 2020, and institute a mandatory emissions reporting system to monitor compliance. The legislation will also allow for market mechanisms to provide incentives to businesses to reduce emissions while safeguarding local communities. (source:  Environmental Defense)
- Discovery of Global Warming
- Ad Council Advertisements
- Vattenfall’s Global Climate Impact Abatement Map
- Climate Crisis Website for An Inconvenient Truth (starring Al Gore)
- RealClimate Climate Scientists' blog
- "Laurie David: Waking Up Ameerica to Climate Change." E Magazine Article
- Who Killed the Electric Car Movie written and directed by Chris Paine about how the EV1 was taken out of production and the last cars crushed.
- the IwantCleanAir site California Global Warming Solutions Act Will Be Law
- Intergovernmental Panel on Climate Change
- Happy is the Columnist who has no history William F. Buckley's Problem With the Climate Science Consensus
- The Myth of 1970s Global Cooling Consensus a survey of climate change literature from 1965 through 1979 by Thomas Peterson and William Connolley
dKos diaries and discussion
Climate Change Effects:
Climate Change Action: