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Global Dimming

September 6th, 02007 by Alexander Rose

This documentary by the BBC on Global Dimming is probably the most alarming global climate issue I have seen to date (and I was reminded of it this morning as the sun was dimmed from a local fire). It points out the simple long term agricultural measurements that show the amount of sunlight hitting the earth has been decreasing over the last century by anywhere from 10-30% (depending on the continent). If this is true, the ambient temperature should be cooling drastically, but the current trend is the opposite. This would mean that the soot and particulates being put into the atmosphere by human activity such as fires and industry, are actually masking the effects of global warming by a huge degree.

Discussed in the documentary are the ten days that planes stopped flying in the US after 9/11. This had a measurable increasing effect on sunlight and ambient temperature. The most daunting part about this dimming notion, is that it means that if we continue to clean up emissions that are dimming the planet, we might accelerate global warming. This would mena that we MUST also reduce greenhouse gases at the same time, and it must be coordinated globally. If these are not done in concert with one another, the countries that are decreasing their emissions, will be increasing their temperature instead of decreasing it. It is postulated in this documentary that the recent deadly heat waves of Europe and Africa are in fact the earths response to decreased emissions in Europe.

This entry was posted on Thursday, September 6th, 2007 at 10:41 am and is filed under Futures, The Big Here. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

One Response to “Global Dimming”

  1. Ville Says:

    Posted on September 7th, 2007 at 12:59 am

    Didn’t your mom tell you not to trust random tv programs? The documentary is discussed on realclimate at http://www.realclimate.org/index.php/archives/2005/01/global-dimming/ (or at http://www.realclimate.org/index.php/archives/2006/04/global-dimming-and-climate-models/ if you actually saw the edited US version). Summing up the detailed article a bit (or my understanding of it): the documentary in question is alarmist, exaggerates things and does not reflect the general understanding of the effect of aerosols on climate change.

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