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More repercussions of a warming planet

  1. Oct 18, 2005 #1
    From last week's Science Daily headlines:

    Underlying Cause Of Massive Pinyon Pine Die-off Revealed


    The article says nothing about man's contribution to warming; it is merely another datapoint of the changing face of the planet.
  2. jcsd
  3. Oct 18, 2005 #2
    However, the summary for policy makers is mainly concerned about increasing precipitation:

    Obviously if global warming is about water vapor feedback, the atmospheric contents of water vapor should also be increasing, causing more precipitation.

    Perhaps indeed we see a problem here, accounting aridness to global warming. Incidentely, if you have Google earth installed, why not fly over the Sahara and see the incredible density of empty river beds, not caused by anthropogenic global warming.
    Last edited: Oct 18, 2005
  4. Oct 18, 2005 #3
    (I assume the river beds had millennia (times millennia) to dry out... so I don't know that such a google-earth would be informative of anything relevant to the present question!)

    My understanding of the models include more extreme weather across the board. More "climate dysjunction" as I linked a few weeks ago. More severe rains, more droughts, more heat waves, and so on.

    I am glad to see from your source that we will not become a desert planet (not that I thought we would). Your information is also consistent with models --- climate change is predicting changes in weather patterns.

    thanks Andre, always a pleasure.
  5. Oct 18, 2005 #4
    Coincidentally this headline ran the same day as the pinyon pine story. It describes how precipitation intensity (the strength of a downpour) and drought could both increase in the same area.

    Warmer Seas, Wetter Air Make Harder Rains


    Again, nothing in this article concrete about man's contributions, though greenhouse gasses are said to be increasing in the article, which hints that the authors lie within the consensus opinion. The *science* in the article is looking simply at how a warming planet affects the extremes of weather. Heavier rains, more droughts, etc.
  6. Oct 19, 2005 #5
    Incidentely noticing the pertinent language (will this, will that) your article is an excellent example of the promotion of models from producing predictions to verify the validity of a hypothesis to a prediction of the future.

    or from http://www.crichton-official.com/speeches/speeches_quote04.html [Broken]:

    Moreover it does not make sense. Strong weather hinges on two factors, high surface temperatures and more importantly high temperature gradients in the lower atmosphere causing the atmosphere to be unstable. The way greenhouse gas is supposed to work, the atmosphere warming up due to IR absorption hence the gradients will decrease, making the atmosphere more stable. Hence it's not logical at all that greenhouse gas warming causes more extreme weather.
    Last edited by a moderator: May 2, 2017
  7. Oct 19, 2005 #6
    Oh and the Sahara turned from moist to arid and back several times some 4000 years ago.
  8. Oct 19, 2005 #7
    Furtermore, I wonder why these kind of hell and disaster shouting publications, which are actually only discussing (GIGO) models, get all the attention; whilst conveniently overlooking reality check publications like http://www.cru.uea.ac.uk/~nathan/pdf/437496a.pdf [Broken]

    Last edited by a moderator: May 2, 2017
  9. Oct 19, 2005 #8
    Intriguing stuff.

    My position is certainly not "The models are right" and again, I know of no scientists with that mindset. (models serve many functions but are certainly not something to be adhered to blindly, particularly climate change models!) Crichton earns his pay by writing science-based disaster scenario fiction. He has a unique perspective but is given to extremity in his writing.

    My position is more along the lines of "Our best scientific understanding is that GHG emissions are contributing to climate change. We see dramatic change in climate already (not modelled, but real and present) so let's try to curb emissions, as we recognize those are a likely significant contributing factor. Curbing emissions may or may not solve the problem completely, but based on our current understanding it could help the situation."
    Last edited: Oct 19, 2005
  10. Oct 19, 2005 #9
    Dear Patty,

    How sure are we that "dramatic change in climate already" are really unnatural? We say dramatic climate changes thoughout the Pleistocene and Holocene. Is there really something new?

    if you'd have the time to study the comprehensive overview of Spencer Weart, you will see that are two main incentives for global warming, a little bit of Arrhenius' inaccurate GHG effect calculations but mostly the perception of the ice ages, assuming that big warming and GHG concentrations are perfectly synchronised.

    That second factor however is completely out of control. Not everybody has taken the time to read and combine a few hundred ice ages papers and abstracts very critically, knowing what the main problems are: misinterpretation of isotope ratio changes and the failure to correct old carbon datings with the modern calibration tables (like INTCAL04 Reimer et al 2004). Abbarations accumulate to over 4500 years or some 25% which makes apparantly codating events to be in fact thousands of years apart - but nobody is interested anymore.

    After having done that, remaining is a perfectly clear mechanism that answers most of the questions like the Mammoth extinction for instance but it also makes clear that we are seeing totally different -noneless physically sound and quantifiable- things in the cores. This falsifies the alleged correlation between CO2 and temperature. Of course there have been major temperature changes but not synchronized with the isotopes.

    If science would have know about those mentioned factors 20 years ago, then there would not have been a global warming hype at all, because it would not have made sense whatsoever.
    Last edited: Oct 19, 2005
  11. Oct 19, 2005 #10
    I have never said that we know that present warming is "unnatural." Rather, I have said that we know that the planet is warming. It's warming dramatically (from a climate standpoint; this is not to be seen as a doomsday statement), and it's warming hand-in-hand with humans coming to dominate the planet. We are past the "natural" carrying capacity of the planet, and are needing to deforest and burn fossil fuels (etc, genetic engineering of crops, diversion of waterways, etc etc) in order to feed the population load of humans on the planet.

    To the extent that we have changed the planet to sustain our own lives (converting large tracts of diverse biological systems such as forests to single-plant-species environments like cornfields, and using "artificial" methods such as burning petroleum products to accomplish large scale farming), and remembering that systems on the planet are interconnected, it seems likely to me that you simply cannot remove humans from the equation of how climate is changing.

    I've never personally put a percentage on how much of climate change can be attributed to people's activity, but it is obvious that we are a part of the system. Since we are fortunate enough to have intelligence and foresight, it seems reasonable to "make our best guess" to avoid further disruption of non-human natural systems on the planet (ecosystems, etc.) This best guess, in my opinion, includes reduction of fossil fuel consumption.

    Thank you for the link. I'll visit it.
  12. Oct 19, 2005 #11
    Why? Is 0,6 degrees C in more than a century dramatical or the current trend of some 0,15 degrees per decade? Oh yes we had a few good summers. But according to the ice core specialists Earth endured temperature changes of about 10 degrees per decade at the end of the Pleistocene. They are wrong and I can explain why, but several spikes of the Moberg 2000 years reconstruction are certainly matching the current temperature changes. Moreover despite the shouting headlines, the lower troposphere is still unwilling to concur with those fast temperature changes.

    My early investigations brought me to Plato's Atlantis very quickly. Why? The Mammoths went extinct at the end of the Younger Dryas, some 11,600 Before Present ("Present" being 1950) and Atlantis was supposed to be destroyed 9000 years before Solon's trip to Egypt. Which is 1950+530+9000=11,480 years BP. Is the stunning accuracy of about 1% enough to assume that the destruction of Atlantis and the extinction of the Mammoth had the same cause..?

    Perhaps you understand that I was fully convinced of that idea for several months until somebody else explained/proved that Atlantis is really a myth indeed in a most brilliant way. It thaught me about the "affirming the consequence"-fallacy the hard way. Coincidence can never be ruled out.

    A definite maybe. Use of fossil fuels should be terminated (eventually) to transit to a sustainable/renewable energy source but it does not have much (if any) impact on climate. The essential difference is where to put priorities. I don't know the schedule to accomplish a sustainable energy management but I'm sure that there is considerable priority for a lot of environmental issues to solve directly, disregarding futile CO2 and climate issues
  13. Jan 20, 2006 #12
  14. Jan 20, 2006 #13


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    Ethiopia is a bad example. It is "chronically food insecure" meaning even the slightest reduction in food output due to normal year-to-year fluctuations causes a famine. Ie, the 1984 famine.


    So far, there have not been any climate issues that can really be pinned on global warming.
  15. Jan 20, 2006 #14
    Lack of foreign investment in infrastructure and technology (electricity, cars and distillation facilities) makes things much worse.
  16. Jan 20, 2006 #15


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    Oh yes, blame it on the US and Europe. Everything is their fault.

    I would like to see a reference for that so as to expand my knowledge.

    Thanks you,
  17. Jan 20, 2006 #16
    Droughts are caused mainly due to natural conditions rather than political ones. Thus global dimming, contamination, distruction of forests and lack of infrastructure and technology all worsen the situation.
  18. Jan 21, 2006 #17
    Well since you ask so politely :biggrin:

    This one mentions the 4000 years:

    http://www-bprc.mps.ohio-state.edu/Icecore/589.pdf [Broken]

    the basic standard work on the African Humid Period makes it end a little earlier (5,5 Kya) is:

    deMenocal, P. et al., 2000. Abrupt onset and termination of the African Humid Period: rapid climate responses to gradual insolation forcing. Quat. Sci. Rev. 19, 347-361.

    But I can't find a easy link right now. If you want a copy PM your E-mail address.


    http://www.ldeo.columbia.edu/~peter/Resources/deMenocal.Science.2000.pdf [Broken]

    http://www.pik-potsdam.de/~claussen/papers/claussen+al_africa-hotspot_igbp_02.pdf [Broken]

    The African Humid Period ties in extremely well with the Non calor sed umor hypothesis.
    Last edited by a moderator: May 2, 2017
  19. Feb 3, 2006 #18
    recent studies seem to have shown a rapid meltdown of arctic ice cap. it is also being predicted(i saw this in the news) that melting is so rapid that arctic icecap would vanish in 100 years (about). so it seems the planet is warming. now the question is why? the standard explanation is due to greenhouse effect of fossil fuels. do you have an alternative mechanism of rising temperatures that we see today?
  20. Feb 4, 2006 #19
    Hi Sage,

    That 100 year is the result of positive feedback of scaremongering and the need to be scared as explained http://www.opinion.telegraph.co.uk/opinion/main.jhtml?xml=/opinion/2006/02/02/do0201.xml&sSheet=/opinion/2006/02/02/ixopinion.html [Broken]

    So it's probably the best to allow the scaremongering. Suppose that there was no global warming myth what else would we find to scare the h... out of us.

    Anyway, can't find a reference so far but the difference in rate of accumulation of the summit and the melt off at the edges is such that melting would take some 20,000 years. But it had not melted during the much warmer Holocene thermal optimum (Hypsithermal), Roman warm period and the Medieval Warm Period, so why should it now? Anyway the extend of the ice is still bigger than at that time when the Vikings settled there and called it "green"-land (and that's not green snow)

    We have an excellent explanation for the current warming nowadays: lack of clouds. It's in this thread.
    Last edited by a moderator: May 2, 2017
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