Drifter Tracking Chart is also available for download. While this remains a useful site for ocean researchers, an educational activities section provides classroom tools as well. Scientists have known for years that cloud formation is an extremely dirty business that depends on microscopic particles from the surface of the Earth. You can find out what scientists have discovered about clouds and the effect of fossil fuel burning on cloud formation in Every Cloud Has a Filthy Lining now available in the Study at NASA's Earth Observatory . This final revision reflects changes in response to public comments and goes into effect November 8, 1999.
Additional articles cover activities in the United Kingdom and Mexico.
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