Archive for the 'Greenhouse gases' Category

As governments around the world consider more rigorous controls on carbon emissions to fight the effects of global warming, I’ve noticed that many critics of these measures are quick to cite the fact that many scientists during the 1970’s were talking about global cooling and the beginning of a new Ice Age.

At first, this seems like a compelling argument against regulating carbon emissions, but that was the 1970’s and this is 2007. Climate change is extremely difficult to predict and a climate study in 2007 is going to be much more accurate considering the advances technology during the last several decades. Plus, there were more pressing problems then the carbon dioxide emissions that trap heat in the lower atmosphere. Scientists, politicians, and public were focused on particulate and sulfuric acid pollution because of problems like acid rain. In addition, it was feared that all this particulate matter in the atmosphere would block some of the sun’s energy and cause the surface to cool down. Finally, there was evidence that the planet was entering into the ice age part of the planet’s climate cycle. (This is a big topic that deserves a lot of articles, so stay tuned for that.)

Anyway, as laws that mandated cleaner air were (for the most part) a success, more and more attention was directed towards carbon dioxide emissions. Scientists began to realize that warming effects were overwhelming the trend of global cooling!

So, the moral of the story is that bringing up climate science from the 1970’s isn’t really an effective argument because of the advances in technology.

Stay tuned for more on climate change on our planet: look for articles about the past, present, and future of our climate.

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew

Source:
1. “Remember Worries About Global Cooling?”

“Friday, 2 February 2007 may go down in history as the day when the question mark was removed from the question of whether climate change has anything to do with human activities” — Achim Steiner, Executive Director of the United Nations Environment Program (UNEP) [1]

In an important report published yesterday in Paris, France the Intergovernmental Panel on Climate Change (IPCC) declared that human are “very likely” a cause of global warming. While this isn’t exactly breaking news, what is significant is that in a 2001 report the IPCC said humans are “likely” a cause of global warming. In more concrete terms, the IPCC definition for likely is a 66-90% probability. This means the probabilty of a human effect is now greater than 90%. [2]

Another interesting paragraph of the IPCC Executive Summary read the following:
“The observed widespread warming of the atmosphere and ocean, together with ice mass loss, support the conclusion that it is extremely unlikely that global climate change of the past fifty years can be explained without external forcing, and very likely that it is not due to known natural causes alone.” [3]

Other highlights from the IPCC report:
1. By the end of the century, temperatures will probably rise 1.8-4C (3.2-7.2F) and could possible rise between 1.1-6.4C (2-11.5F)
2. Sea level likely to go up by 28-43 cm (11-16 inches)
3. By the second half of the century, Arctic sea ice will disappear entirely during the summer months.
4. Eleven of the last 12 years are some of the warmest on record
5. Changes in weather patterns will lead to longer and more intense droughts, heatwaves, and tropical storms.

The IPCC will release a full report later this year and will release reports on how to adapt to climate change and suggestions towards reducing greenhouse gases. Stay tuned for more updates.

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew

Sources:
1. “Analysis: Through the climate window” by Richard Black, BBC News
2. “Humans blamed for climate change” by Richard Black, BBC News
3. IPCC report (PDF), released on February 2, 2007