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Advertising GOODBYE air pollution and smoky chimneys, hello brighter days. That's been the trend in Europe for the past three decades - but unfortunately cleaning up the skies has allowed more of the sun's rays to pierce the atmosphere, contributing to at least half the warming that has occurred. Since 1980, average air temperatures in Europe have risen 1 C: much more than expected from greenhouse-gas warming alone. Christian Ruckstuhl of the Institute for Atmospheric and Climate Science in Switzerland and colleagues took aerosol concentrations from six locations in northern Europe, measured between 1986 and 2005, and compared them with solar-radiation measurements over the same period.
"The decrease in aerosols probably accounts for at least half of the warming over Europe in the last 30 years," says Rolf Philipona, a co-author of the study at MeteoSwiss, Switzerland's national weather service. The latest climate models are built on the assumption that aerosols have their biggest influence by seeding natural clouds, which reflect sunlight. However, the team found that radiation dropped only slightly on cloudy days, suggesting that the main impact of aerosols is to block sunlight directly. Climate Change Want to know more about global warming: the science, impacts and political debate?
From issue 2663 of New Scientist magazine, 09 July 2008, page 16 Comment subject Comment No HTML except lower case italic tags or lower case bold tags, please: <i> or <b> Your name Your email We need your email in case we need to contact you about the comment.
VIEW THREAD >> Global Warming Myth By Michael W Morgan Thu Jul 03 19:21:49 BST 2008 Let's see: 1960 Pollution is bad. More 1980 Clean Air Legislation, minimum milage 1990 requirements.
REPLY Global Warming Myth By Dan Conine Thu Jul 03 21:31:08 BST 2008 Some of us are listening, and always have been. The problem is that the vast majority of human activity is based upon the economics and unchecked social drivers of advertising and incorporation (liability limiting). All of our governments and systems are designed only for perpetual growth. We even have rules and intellectual property systems designed to stimulate the conversion of natural resources at faster and faster rates, while more than 90% of those resources are in landfills or in the atmosphere within 6 months. There is little motivation to question these systems of reap and dump. The monetary Economy is really a non-recyclable waste product of human activity, and the Federal Reserve has run out of places to dump it.
REPLY Global Warming Myth By Hyonmin Sun Jul 06 01:31:49 BST 2008 Dan Go to engineering school and learn. Certainly get your numbers right (90% of resources in landfills, please we should all stop pooping for a day to conserve).
VIEW THREAD >> Global Warming Myth By Vendicar Decarian Wed Jul 09 19:17:44 BST 2008 "Let's see: 1960 Pollution is bad. If you want the air you breathe to be dirty, then take up smoking, or start an open fire in the middle of your living room.
VIEW THREAD >> Cleaned Up Skies By Tim Mcdonald Thu Jul 03 20:49:01 BST 2008 The reduction in vapour contrails due to fewer flights as a result of higher fuel prices will impact clean air warming even more. It may be an urban myth but I remember comments of measurable warming when US flights were grounded in the days following 9/11. If global air traffic reduces due to the rise in aviation fuel we will be able to check the link between air traffic and surface solar radiation.
VIEW THREAD >> Cleaned Up Skies By Chris Wininger Wed Jul 09 22:58:43 BST 2008 New Scientists had an article on this not long ago as well. There are lots of myths/conspiracy theories regarding contrails but what you are talking about is a real effect. I'm not sure if it is a strong enough effect to have actually been the sole cause of any warming that happened following 9/11 but contrails do have a slight cooling effect on global temperatures. I think the problem is there are simply too many variables for any one model we create to accurately predict the consequences of our actions. On top of that weather is a chaotic system and digital computers lack the noise to generate such systems. That's why our best bet is going to be to try and reduce consumption and scale down society. We are never going to be able to predict and control the consequence of actions performed on such mass scale inside such a sensitive system. That may be the positive side the economic downturn and rising fuel prices. You don't get energy from nothing and it never disappears, hence equal and opposite reactions. With as many people as we have on the earth today and with the scale of industry we are bound to alter the planet. Think of the old anecdote from chaos theory made popular by Jurassic Park, the butterfly flaps its wings in the Amazon and you have rain in New York. We cant predict the effect of this anymore than we can predict the effect of a single butterfly flapping its wings but guarantee you its going to be larger than rain in New York. Let's just hope we can keep up with the changes otherwise we'll die out to make way for something that can;
VIEW THREAD >> Agw By Stu Thu Jul 03 23:06:43 BST 2008 My main suspicion over this is the use of climate models. Climate models are not Science and they are prone to inherent weakness. I am no expert, not by a long shot, but this seems to be the consensus of opinion that I have encountered. The general public often fail to read between-the-lines of media reports of areas where they have no personal experience. I suspect AGW is now an axiom, which is worrying when you read reports like this one, where 50% of the warming is actually the result of positive measures. I realise other areas of the world experience effects of AGW and that this weakens my argument. However, if most climate models make such a false assumption, then a lot of the consequential political and social pressure is based on a false premise.
REPLY Agw By Mark King Thu Jul 03 23:19:04 BST 2008 I think it's going too far to say that climate models are not science. They are in effect hypotheses about the raltionship between climate and various factors considered to contribute to it, and they are constantly tested both prospectively and retrospectively - which is the ideal scientific process. If you're arguing that they are usually wrong, that's a different matter. Climate is very complex, and we can expect lots of inadequate models. But what is the alternative - do nothing and hope for the best?
VIEW THREAD >> Agw By Jose Luis Fri Jul 04 20:32:09 BST 2008 As climate models are the only scientific tool we have for medium to long term climate predictions, we are forced to take into serious account the models results. However, we are continually adding new variables to the models --no way to avoid this-- and those new variables may have a strong impact on the direction of the predictions. Right now there model predictions pointing to an accelerating warming and others that alert for a possible sudden cooling of the northern hemisphere (as a result of an eventual stop of the Gullf stream "conveyor belt"). So we have predictions for all tastes, but all of them are negative, I am afraid.
REPLY Agw By Bob Webster Sat Jul 05 12:53:36 BST 2008 The problem with relying on models is that they were not designed to be used as they are. They are intended to show trends based upon what is changed in the drivers input to the system. Then there is the inconvenient reality that climate science/climate change science is simply not that well understood to model in the first place, and if it were, the computation power simply doesn't exist, nor do the datasets, to drive the models with any sensible confidence. Oh yes, then there is the additional inconvenience of not being able to explain any of the past climate variations (over any meaningful time frame) where warming and cooling were far more significant than anything we have seen in the past 100 years. Add to this, the faulty analysis regarding atmospheric CO2 that fails to account for the decreasing capacity of CO2 to retain heat as more is added to the atmosphere and the ina...
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