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Simple view of Global Warming

  1. Mar 11, 2005 #1

    Hers's my simple idea about global warming.

    The suns energy is absorbed by the earth.

    The earth re-emits this energy as heat.

    Human technology emits greenhouse gasses and produces more heat.

    Green house gasses are increasing in the atmosphere.

    The more co2 and other greenhouse gasses in the atmosphere the more of this heat is reflected back to the earth and warms the earth and the lower atmosphere, while the upper atmosphere experiences cooling.

    The global average temperature has risen about one degree F in the last century with larger increases in the higher latitudes.

    Artic sea ice has thinned around 50% in the last century or less.

    Glaciers are melting at a much higher rate today all over the world.

    Seems like global warming is real to me.

  2. jcsd
  3. Mar 11, 2005 #2


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    Yes that is a very simple view of things. The suns energy is absored by the atmosphere but with higher concentrations of CO2, more energy is passing through. Human technology does emit these gases but no one can confirm that they are the acutal problem. There are a few CO2 pockets in the ocean that, if released, would make man kind's contribution to CO2 in the atmosphere seem like a mole hill compared to a mountain. Scientiests also do not know what is actually causing the warming and hte rise in temperature is much higher then that. So yes, very simple view on things.
  4. Mar 12, 2005 #3

    Still this simple view points to the fact that at least some of the warming is due to human activity. How much is yet to be determined. Could be a high, medium, or low percentage.

  5. Mar 27, 2005 #4
    Global Warming is caused by the sun. Have you ever noticed that it gets hotter & hotter from summer to the next summer?
  6. Apr 6, 2005 #5
    Because the Earth is experiencing a 1 degree change in overall temperature in the last century does not seem like evidence to me of global warming caused by humans. The Earth goes through natural changes all by itself. Throughout history there have been times when the Earth has been very warm and has also been through ice ages. What causes these changes could be catastrophic events like massive volcanic eruptions or massive meteor strikes, or it could be a natural evolution of the planet. However, I think it would be foolish to not account for human interference. We do release greenhouse gases into the atmosphere and they do have some effect on the environment. The question is, how much of an effect? Juju is right about CO2 deposits in the oceans, and as the temperature rises more of this CO2 will be released into the atmosphere. Also, as we deforest the planet, especially the rainforests, we release CO2 captured in trees and reduce the planets ability to transfer this gas into oxygen. It's a problem that we should be concerned with whether we are directly responsible or not. We could be headed for a positive feedback loop that continuously increases global temperature. Then again...
  7. Apr 8, 2005 #6


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    no, there has not been a global linear temperature increase (although recent summers have included some of the hottest on record in some areas)

    even if there was, how does that tie to your first statement that it's only sun induced?
  8. Apr 8, 2005 #7


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    Note that claims that anthropogenic global warming is occuring are not based on that observation alone. For example, the IPCC report includes graphs that show that the observational data best fit a climate model that includes both natural and anthropogenic effects (i.e., better fit than just natural effects alone or anthropogenic effects alone). As you said, the trick will be figuring out how much of the climate change is due to human activity vs. natural causes (the estimates on human input seem to range from 5% to 75%).
  9. Apr 8, 2005 #8
    Are the martian polar caps receding, year after year? Wouldn't that indicate if the sun is getting hotter, regardless of human intervention?
  10. Apr 9, 2005 #9
    Methane gas is a very good 'green gas' more effective than CO2. Methane is produced from human and animal excreta(especially cows in my country). Many industrial and chemical factories also produce this gas contributing to the 'Greenhouse Effect'.
  11. Apr 17, 2005 #10
    Here are some useful links for more information about global warming:

    A Brief History of Climate Change

    'Urgent need to cut greenhouse gases'

    The science debate behind climate change

    It seems that governments and scientists are now recognizing global warming to be a serious threat to the future of humanity and are taking steps to rectify this important issue.

    U.N. Study: Earth's Health Deteriorating

    Seeking solutions to a cooler planet

    Kyoto Report

    Text of the Kyoto Protocol (Treaty to cut greenhouse gasses)
  12. Apr 18, 2005 #11

    Ivan Seeking

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    Last edited: Apr 18, 2005
  13. May 14, 2005 #12
    There's no question that global warming is real. Even the oil industry accepts it as a matter of fact. But not everyone is happy about that. Once again, politics, rhetoric, and propaganda will probably win over facts, logic, and truth. The Scientific Alliance, btw, is partially funded by the oil industry. I found it interesting that they would report that article when it damages the reputation of one of their own advocates.

    I remember watching a program on Nova a couple of decades ago. It included a graph of the average temperature derived from ice cores going back millions of years. What I found particularly noteworthy was that all the ice ages began after a brief, (100 to 1000 years or so), spike in global temperatures. First the spike, then the plunge, lasting thousands to tens of thousands of years.

    I think the gaia theory is essentially correct, but there are limitations. Once a certain percentage of arable landmass becomes desert, something happens to the runaway greenhouse effect. It seems to plunge us into an ice age. For my money, it is this that we should be investigating.
  14. Jun 21, 2005 #13


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    Methane is about 21 times* more effective than CO2 as a greenhouse gas, but CO2 is believed to play a larger role in Global Warming due to its much higher concentration (something like 1 ppm vs. 370 ppm on average, IIRC) and much longer life in the atmosphere....over 50% of the effect is from CO2.

    * on a 100 year timescale...over longer timescales, the comparative effectiveness is less given that CO2 sticks around much longer than methane
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