Human-€induced climate change requires urgent action

Discussion in 'Politics' started by futurecurrents, Aug 7, 2014.

  1. The greenhouse effect works like this: Energy arrives from the sun in the form of visible light and ultraviolet radiation. The Earth then emits some of this energy as infrared radiation. Greenhouse gases in the atmosphere 'capture' some of this heat, then re-emit it in all directions - including back to the Earth's surface.

    Through this process, CO2 and other greenhouse gases keep the Earth’s surface 33°Celsius (59.4°F) warmer than it would be without them. We have added 42% more CO2, and temperatures have gone up. There should be some evidence that links CO2 to the temperature rise.
     
    #11     Aug 7, 2014
  2. How long has CO2 been contributing to increased warming? According to NASA, “Two-thirds of the warming has occurred since 1975”. Is there a reliable way to identify CO2’s influence on temperatures over that period?

    There is: we can measure the wavelengths of long-wave radiation leaving the Earth (upward radiation). Satellites have recorded the Earth's outbound radiation. We can examine the spectrum of upward long-wave radiation in 1970 and 1997 to see if there are changes.


    [​IMG]

    Figure 2: Change in spectrum from 1970 to 1996 due to trace gases. 'Brightness temperature' indicates equivalent blackbody temperature (Harries 2001).

    We see that during the period when temperatures increased the most, emissions of upward radiation have decreased through radiative trapping at the wavelengths of each GHG.
     
    #12     Aug 7, 2014
  3. We know CO2 absorbs and re-emits longwave radiation (Tyndall). The theory of greenhouse gases predicts that if we increase the proportion of greenhouse gases, more warming will occur (Arrhenius).

    Scientists have measured the influence of CO2 on both incoming solar energy and outgoing long-wave radiation. Less longwave radiation is escaping to space at the specific wavelengths of greenhouse gases. Increased longwave radiation is measured at the surface of the Earth at the same wavelengths.

    These data provide empirical evidence for the predicted effect of CO2.
     
    #13     Aug 7, 2014
  4. Arnie

    Arnie

    And there you have it. The one important word in that whole paragraph....a theory
     
    #14     Aug 8, 2014
  5. Well, you think it is important because you don't know what the word means with regards to science.

    Let me help you out, because honestly, this confuses many ignorant people.


    The United States National Academy of Sciences defines scientific theories as follows:

    The formal scientific definition of "theory" is quite different from the everyday meaning of the word. It refers to a comprehensive explanation of some aspect of nature that is supported by a vast body of evidence. Many scientific theories are so well established that no new evidence is likely to alter them substantially. For example, no new evidence will demonstrate that the Earth does not orbit around the sun (heliocentric theory), or that living things are not made of cells (cell theory), that matter is not composed of atoms, or that the surface of the Earth is not divided into solid plates that have moved over geological timescales (the theory of plate tectonics)...One of the most useful properties of scientific theories is that they can be used to make predictions about natural events or phenomena that have not yet been observed.[17]


    We can add to the above the "theory of greenhouse gasses". No new information will change the fact that GHG's absorb then reemit longwave radiation (heat).
     
    #15     Aug 8, 2014
  6. Arnie

    Arnie

    #16     Aug 8, 2014
  7. Lucrum

    Lucrum

    Yeah there seems to be more and more of this going around lately.

    :D
     
    #17     Aug 8, 2014
  8. jem

    jem

    NASA recently stated CO2 is one of the most efficient coolants in the atmosphere.
    It is a thermostat. It does not just warm... it cools and balances.


    http://science.nasa.gov/science-news/science-at-nasa/2012/22mar_saber/

    Carbon dioxide and nitric oxide are natural thermostats,” explains James Russell of Hampton University, SABER’s principal investigator. “When the upper atmosphere (or ‘thermosphere’) heats up, these molecules try as hard as they can to shed that heat back into space.”
    That’s what happened on March 8th when a coronal mass ejection (CME) propelled in our direction by an X5-class solar flare hit Earth’s magnetic field. (On the “Richter Scale of Solar Flares,” X-class flares are the most powerful kind.) Energetic particles rained down on the upper atmosphere, depositing their energy where they hit. The action produced spectacular auroras around the poles and significant1 upper atmospheric heating all around the globe.
    “The thermosphere lit up like a Christmas tree,” says Russell. “It began to glow intensely at infrared wavelengths as the thermostat effect kicked in.”
    For the three day period, March 8th through 10th, the thermosphere absorbed 26 billion kWh of energy. Infrared radiation from CO2 and NO, the two most efficient coolants in the thermosphere, re-radiated 95% of that total back into space.

    here is some of the data in a graph... this is what we will need from the agw nutters... real data supporting opinion.

    [​IMG]
     
    #18     Aug 8, 2014
  9. jem

    jem

    agw science scoreboard at the end of the intial round.
    agw nutters are down by 1.

    Science showing that adding man made co2 is currently warming the earth - 0
    Science showing we are not sure what adding man made co2 does - 1
    ----------------------
    In this second round... we ask the agw nutters...
    To provide science that man made co2 is currently warming the earth.
    Not that the earth is warming... not that man is causing warming...
    but science showing man made co2 is causing warming.

    you have 24 hours for round 2.
    links to the data or graphs of the data supporting opinions are necessary.
     
    #19     Aug 8, 2014
  10. You must have missed post # 12 Look again.
     
    #20     Aug 8, 2014