More on global warming

Discussion in 'General Science & Technology' started by timojin, Jun 13, 2017.

  1. Xelasnave.1947 Valued Senior Member

    Messages:
    8,502
    I know I am being negative but I sat thinking and tried to imagine a world where it has gone down hill but somehow some survive and adapt to this new world. Houses under ground maybe...er caves.
    Alex
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. mcurie Registered Member

    Messages:
    6
    I always wonder if humans will someday populate mars. They would need to find a way to create a magnetic field first though... maybe... possibly?
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. exchemist Valued Senior Member

    Messages:
    12,451
    Why do you focus on that? Deflection of high energy particles?
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Xelasnave.1947 Valued Senior Member

    Messages:
    8,502
    So they can use a compass in the dust storm.
    Alex
     
    exchemist likes this.
  8. DaveC426913 Valued Senior Member

    Messages:
    18,935
    Pretty sure we won't be colonizing Mars without GPS satellites.
     
  9. DaveC426913 Valued Senior Member

    Messages:
    18,935
    We would survive. But it would suck.
     
  10. Thales Registered Member

    Messages:
    36
    What is the central argument of proponents of "anthropocentric climate change"? Where should I begin?
     
  11. sculptor Valued Senior Member

    Messages:
    8,466
    Atmospheric forcing via injection of CO2
     
  12. Thales Registered Member

    Messages:
    36
    What?
     
  13. DaveC426913 Valued Senior Member

    Messages:
    18,935
  14. mcurie Registered Member

    Messages:
    6
    I'm not sure if it's synonymous...
     
  15. Thales Registered Member

    Messages:
    36
    This other thread posted under "Earth Science" has been very interesting.
     
  16. billvon Valued Senior Member

    Messages:
    21,634
    Well, it's "anthropogenic climate change." That word is important; anthropogenic means "created by Man."

    The climate changes all the time, and has for as long as the Earth has been around. In Man's history we have seen a few climactic changes - the Maunder Minimum for example. This is natural.

    However, lately we have been forcing rapid changes to the climate. Specifically, we are adding greenhouse gases to the atmosphere (mainly CO2 and methane) that cause an increase in retained heat. This warms the climate rapidly. This can cause various problems for the biosphere and Man himself, from mass extinctions as the environment changes to property loss as seas rise.
     
  17. Thales Registered Member

    Messages:
    36
    How do you know, billvon?
     
  18. origin Heading towards oblivion Valued Senior Member

    Messages:
    11,888
    He probably is looking at the data and listening to the Climatologist.
     
  19. Thales Registered Member

    Messages:
    36
    ?
     
  20. billvon Valued Senior Member

    Messages:
    21,634
    Well, there are three parts to it:

    1) Carbon dioxide and methane are greenhouse gases; they pass short wavelength light but block long wavelength infrared. You can demonstrate this in a high school chemistry lab with some simple equipment, so there's not much controversy there.

    2) Increasing the concentration of greenhouse gases in a planet's atmosphere will warm a planet. We've seen extreme examples on Venus, which has a surface temperature hot enough to melt lead. Here on Earth we can observe the infrared we emit from the ground vs the amount that makes it into space, and can then calculate how much more heat we are retaining.

    3) We are increasing the amount of CO2 in the atmosphere by burning fossil fuels, and we are releasing methane because in many cases it's a waste product from human projects (i.e. sewers, oil wells, landfills) We can easily calculate how much CO2 we release, for example, by calculating the amount of coal and oil we burn, and since we know the composition of those materials, we know how much carbon they contain (and thus how much carbon is released into the atmosphere.) We also know how much atmosphere there is. Using those two facts, we can calculate how much we are increasing CO2 concentrations every year. And in fact they have been rising year after year - from 280 ppm to over 400ppm today.

    To validate all this, it would make sense to model it, then see if actual climate matches the model. To do this, the above three facts were fed into models as early as 1990, and predictions were made as to what would happen to global temperatures in the future. Those predictions have come very close to reality, thus validating the models.
     
    James R, origin and exchemist like this.
  21. iceaura Valued Senior Member

    Messages:
    30,994
    Side point: we can also measure how much we are increasing the CO2 concentration every year directly, by frequently sampling the air over many years in suitable locations and analyzing the samples (the CO2 we add comprises an identifiable combination of isotopes, different from CO2 from other sources). This has been done: https://www.esrl.noaa.gov/gmd/ccgg/trends/
     
    Last edited: Dec 4, 2017
  22. DaveC426913 Valued Senior Member

    Messages:
    18,935
    Well, if you Google 'atmospheric forcing', the first page of hits is 'radiative forcing'.

    But you're right; I didn't mean literally synonymous; radiative forcing would be the term to research if you wanted to gets answers to the question(s)asked in the OP.
     

Share This Page