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| Thread ID: 83145 | 2007-09-20 23:04:00 | Climate change caused by man ? | wmoore (6009) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 593470 | 2007-09-21 08:04:00 | Pollution from us is certainly a very large factor in global warming. However the planet does heat up and cool down - it's been happening all the earth's life, apparently. Kinda weird though, the last ice age was only about 12000 years ago - seems kinda too fast for the planet to warm up this quick. |
qazwsxokmijn (102) | ||
| 593471 | 2007-09-21 08:26:00 | Nope, women did it. ;) :lol: :lol: :lol: |
rob_on_guitar (4196) | ||
| 593472 | 2007-09-21 09:33:00 | The climate change we are experiencing had it's genesis in the industrialisation of the 19th century . Factories spewing out millions of tons of soot . And we've just continued on that way for 150 years . Our factories may be relatively clean in the West but our vehicles more than make up for that . In the developing world it is business as usual . Most of Asia (including China) is covered by a brown haze from pollutants . The Artic tundra is warmng up, releasing organic carbon . This reaches the oceans and acidifies the water . Marine life forms commonly use calcium compounds to make shells, exoskeletons etc which dissolve in acid water . Whether you accept this or not - and there is plenty of scientific research - the political steps to counter global warming are really anti-pollution measures . Pollution will kill us unless we can halt poisoning our environment . Rant over . :thumbs: Things are not always as simple as they seem Winston . Pollution actually prevents warming . Clear skies allow more solar energy to reach the earth with the obvious result . . nature . com/news/2005/050502/pf/050502-8_pf . html" target="_blank">www . nature . com |
Safari (3993) | ||
| 593473 | 2007-09-21 09:45:00 | Thanks Safari, I understand that but that is where greenhouse gases come in - they trap re-radiation of infra-red from the surface back into space. Indeed it is very complex and I'm no expert. I simply think anti-pollution is a good thing whether the earth is warming or not. IMHO the greatest threat to humans is our population explosion and possible collapse of the biosphere. | Winston001 (3612) | ||
| 593474 | 2007-09-21 09:57:00 | Our present climate change is not caused by man its just a natural cycle. Bit like the holocaust which didnt happen tedheath |
tedheath (537) | ||
| 593475 | 2007-09-21 10:04:00 | I'd say we aren't helping | Agent_24 (57) | ||
| 593476 | 2007-09-21 10:47:00 | Ostriches - Sand - Head | zqwerty (97) | ||
| 593477 | 2007-09-21 11:33:00 | Can't vote on this. I need the "Caused by nature, assisted by Man" option Ken I'd say we aren't helping ditto but apparently if we can get atmospheric CO2 to over 560ppm we'll prevent the next ice age and since the start of the industrial revolution we've gotten half way there!:lol: and of course as things warm up so will the ocean and co2 solubility in it decreases, releasing more co2 into the atmosphere and the cycle continues but then of course one stray asteroid or nuclear weapon and who'd be left to care? |
motorbyclist (188) | ||
| 593478 | 2007-09-21 11:39:00 | There is no real doubt that the climate is changing . The doubt (for me) is whether we are affecting the climate in any material way . I remember as recently as the seventies that climate scientists were saying we were heading for another ice age . It seems they were wrong . Maybe they're wrong again . Everyone knows how accurate weather forecasts are - NOT! But none of the above means that we shouldn't take steps to prevent pollution - but for me this is merely a side issue in the climate change debate . |
johcar (6283) | ||
| 593479 | 2007-09-21 13:36:00 | From a post I made awhile ago on another site, forgive the choppiness: "Actually, a simple model of what is going on is this. We are in a system with negative feedback applied, as the system is disrupted by internal or external forces the feedback loop acts to hold the system in stability, the bigger the changes the bigger the fluctuations within the control loop which normally have a sine wave shape. As the stability of the system is tested in our case by more energy in the system ie global warming, as the feedback loop loses control the sine wave shape will tend to become a square wave as the limits of control are reached. In this case the world's weather is kept in some form of stability by the sharing of the heat at the Equator with the cold at the poles and vice-versa. See: Gulf Stream and Atlantic Conveyor our feedback loop. The melting of the North Pole (fact) is allowing more fresh water into the North Atlantic which is disrupting the process in ways not fully understood as yet. As this system is disrupted by whatever, we would expect to see more energy at the equator ie more hurricanes and less energy at the poles ie colder Winters on average. The predictions are that there will be wilder weather for a while as the Global warming is exacerbated by our activities then as the feedback loop loses control completely we will go into an ice age for a few thousand years in as little time as 100 years as has happened many times before in the history of the earth. Think of a bi state circuit which temporarily is maintained as a sine wave oscillator by feedback but has now flopped into one or other of the two states possible for a while to get a more accurate picture, I think. Next Summer we will wait with trepidation to see what happens, Europe is already having the predicted colder Winter. Please note that the main factors that make the Earth what it is, ie able to sustain complex life forms unlike anywhere else that we know, is the relatively circular orbit at the right distance from a Sun (stable small star) that puts out most of its energy with a peak in the spectrum where visible light is, the properties of water (H2O being a polarized molecule that floats when it freezes), the moon causing the tides and the tilt in the Earth's axis causing the seasons, also the feedback loop I mentioned above. The net energy coming into the Earth is much the same for a long time now, the "Global Warming" is the poorer distribution of that energy over the planets surface. It is hard to believe that our activities are not making any difference it defies common sense to think otherwise unless you think that god is looking after us, and that is even harder to believe." |
zqwerty (97) | ||
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