Keep Earth Beautiful
Global Dimming |
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Sulfur = chemically S Oxygen = chemically O Sulfur can hold 2 particles of O = SO2 Everybody is talking about Global warmingbut rarely you hear about Global Dimming.When we calculated the effects of greenhouse gases in the 1980ties and compared our findings with reality, we found differences. Some people told us, that all these calculations were nonsense. But for many years now, our calculation are much more accurate - WHY? We had to calculate in a different factor: Global Dimming Visibility on clear days has declined on Earth since the 1970s because of a rise in airborne pollutants. "Global Dimming" can be clearly seen in over south and east Asia, South America, Australia and Africa, while visibility remained relatively stable over North America, except Los Angeles, and improved over Europe. ![]() Smog over Los Angeles Aerosols, tiny particles or liquid droplets belched into the air by the burning of fossil fuels and other sources, are responsible for the dimming. Robert Dickinson of the University of Texas said in an interview: "Aerosols are going up over a lot of the world, especially Asia .." Dickinson and 2 University of Maryland researchers tracked measurements of visibility -- the distance someone can see on clear days -- taken from 1973 to 2007 at 3,250 meteorological stations on Earth. Aerosols like soot, dust and sulfur dioxide particles have harmed visibility. Recent satellite data clearly confirm that the visibility measurements from the meteorological stations were a good indicator of aerosol concentrations in the air. The aerosols from burning coal, industrial processes and the burning of tropical forests influence our climate and are harmful to humans, animals and plants. Aerosols have variable cooling and heating effects on surface temperatures, reflecting light back into space and reducing solar radiation at the Earth's surface and can absorb solar radiation that heats our atmosphere. Carbon dioxide and other so-called greenhouse gases are pollutants too, but they are transparent and do not affect visibility. Scientists blamed increased industrial activity in places like China and India and the huge production of electricity in the US by coal fired powerplants for the decreased visibility. Air quality regulations in Europe helped to improve visibility there since the mid-1980s. So, what do we learn from these "news"? Our wasteful use of fossil fuels is producing massive amounts of greenhouse gases, but all the dust /pollution particles reduce in the moment the speed of "global heat up". NASA scientists have found that a decrease in airborne sulfates-- dirty smokestack particles caused by burning coal and regulated by the Clean Air Act since the 1970s to prevent acid rain and air pollution - may account for as much as 45% of Arctic warming. Dr. Drew Shindell of NASA's Goddard Institute of Space Studies reports: "Sulfates, which come primarily from the burning of coal and oil, scatter incoming solar radiation and have a net cooling effect on climate. Over the past three decades, the United States and European countries have passed a series of laws that have reduced sulfate emissions by 50%. While improving air quality and aiding public health, the result has been less atmospheric cooling from sulfates." These findings may be cause for a real rethinking of climate-change policies. Dr. Shindell works for Dr. James Hansen, earth's leading voice making the demon Carbon Dioxide synonymous with all of society's ills. But Dr. Shindell is recommending that focusing on the effects of aerosols rather than carbon dioxide emissions may be the more effective strategy against climate change and especially the melting of arctic ice. Aerosols--sources range from dirty coal plants to hairspray - include both the cooling sulfates and the ultra-warming, sunlight-absorbing black soot. They appear and dissolve in the atmosphere much more quickly than greenhouse gases, which hang around for centuries, making them an effective target for short-term "geo-engineering" type interventions. Bear Springs Blossom Nature Conservation research is very skeptical to the idea of 'geo-engineering". An engineer needs to know and understand the master plan, and we doubt that todays human knowledge is able to understand the perfection of Nature's plan. |


