6 ms·

Temperature chart for the last 425,000 years: http://ctdonath.blogspot.com/2012/02/global-climate-change-in-context.html?m=1 http://ctdonath.blogspot.com/2012/0

• davyjones 13y ago
  Wait...are we in "summer" on that time-scale now?!
  • ctdonath 13y ago
    Yup. At the end of the Dog Days of August, expecting an early hard frost. We'll be wishing for "warming" soon enough.
• kolbe 13y ago
  Do you know why the original 11,000 year chart doesn't look anything like the 10,000 year chart in your link?
  • wffurr 13y ago
    Different data set. The 10,000 year chart is only Antarctic ice cores. The 11,000 year chart is a composite of a number of temperature records - tree rings, etc.
    • ctdonath 13y ago
      The 11,000 year chart is a composite. Funny how the data takes a wild change right where a completely new data source is included.
      • anon1385 13y ago
        You realise that there is an entire paper in Science about how they synthesised the various temperature records? http://www.usu.edu/geo/physical/MarcottEtal_Science_2013.pdf http://www.usu.edu/geo/physical/MarcottEtal_Science_2013.pdf If you have something constructive to say about the methodology then let us know rather than making ignorant comments that tell us more about your political ideology than about the science.
        • metric10 13y ago
          Let me guess, you're a Republican? The OP made a perfectly legitimate observation. People should be skeptical of anyone trying to prove a point by showing a graph. Thanks for posting a link to the actual science.
        • ctdonath 13y ago
          Another comment notes of that paper:The Science paper says their reconstruction is smoothed and has low time resolution. They say it displays no variation at all on timescales <300 years, and attenuates even 1,000 year variations. Superimposing this with the 30-year Hadley data seems misleading, because it is on a very short timescale which is suppressed from the older data.
  • tehwalrus 13y ago
    I suspect that "geological record" quoted is only one source - the graph in the original link is many sources combined. Also, note the scales are totally different, and that the original link at least states sigma (uncertainty.)
  • anon1385 13y ago
    His chart is based on a single data set (the vostok ice core) for the majority of that period (plus modern temp records slapped on at the end, but it's not visible in the 10,000 year graph) which is not representative of global climate. Correlating proxy records with modern instrument records of temperature is not trivial either (which becomes far more apparent once you look at more than a single proxy record). It's just cherry picked data to make a cheap political point. The scale of the vertical axis makes it very hard to see what is happening during interglacials, which is what we are in at the moment. If we were worried about an ice age arriving in the next couple of centuries the choice of scale might have some merit, to show how much colder it could possibly get. But we are worried about rapid heating, which that scale does a good job of hiding.
    • sliverstorm 13y ago
      Why do people worry about the possibility of entering an ice age? That seems like the sort of thing humanity is much more prepared to survive.
      • EdiX 13y ago
        We are more prepared to survive a 10 degrees drop than a degree and a half increase?
        • sliverstorm 13y ago
          Not so much that a degree warmer is hard to survive, but the associated things that either come along with or are implied by global warming seem more damaging than colder weather and more ice, which we already know humans survived no problem ages ago when they migrated through Siberia and Alaska.
  • mistercow 13y ago
    Possibly because it's a three word AGW denying blog post, and includes only from ice core data from Antarctica, whereas the 11,000 year data in the original post is compiled from multiple combined sources. I'd hate to assume bad faith on the part of a climate change denier, but I can't help but speculate that the data source was chosen specifically because it made the point s/he wanted to make.
    • corresation 13y ago
      but I can't help but speculate that the data source was chosen specifically because it made the point s/he wanted to make You don't thing that isn't happening among those who raise the AGW alarm? As the morally "right" position to hold, it even grants leave to do so righteously.
      • mistercow 13y ago
        "And you are lynching Negroes". I'm not going to respond to this obvious fallacy beyond that.
        • corresation 13y ago
          There is no fallacy here, and your offensive, inappropriate retort has absolutely no place in this discussion. You specifically decided to label one proposing an unwelcome data point as "climate change denier", which in an instant made your position clear, hence my reply.
          • deleted 13y ago
            [deleted]
          • mistercow 13y ago
            >your offensive, inappropriate retort has absolutely no place in this discussion I assume that means you're unaware of the historical meaning behind the quote: http://en.wikipedia.org/wiki/And_you_are_lynching_Negroes http://en.wikipedia.org/wiki/And_you_are_lynching_Negroes The fallacy in question is also known as "tu quoque". Edit: Also, it's interesting how often I point out a fallacy in someone's reasoning, only to have them say "there's no fallacy". In virtually every case, the situation was that they simply didn't see the fallacy. A better answer would be "I don't see the fallacy you're talking about."
  • Gugel 13y ago
    Also, look at the scale of the Y-axis. One has a range of 1C and the other has a range of 15C.
• skoob 13y ago
  Right, lets just "cope" with climate change the same way we did 425,000 years ago. By dying, I guess? What's wierd is that despite that fact that's you've done your best to make AGW look like a non-issue, the chart for the 100 last years looks extremely worrying.
  • ctdonath 13y ago
    Fact is there's a 125,000 year cycle. We're at the high of one, due for a long drop. When I bring out this long term data, funny how many people shriek at it - but there it is, and the "warmers" won't produce any graphs covering the same (or longer) periods. Yes, the data is limited. BUT - I hunted it down, put it together, gave it what I considered fair context, and there it is. Don't like it? counter with your own half-million year graph, not snide religious insults.
    • tstactplsignore 13y ago
      It's almost as if the very scientists who collected, analyzed, and are most familiar with the 125,000 year cycle are also the ones who are very worried about the current trends. The simple point is that CO2 levels are likely higher now than in the last 20 million years[1], and the current rate of temperature change is likely faster now than any time in the last 65 million years [2]. The prehistorical cycles are large, but they are also slow- we're acting on unprecedentedly fast timescales now. How you can be so arrogant is beyond me. Do you think that climatologists, the very people who produced our complete understanding of our Earth's past, are merely unaware of prehistorical cycles? Perhaps they're "ignoring" it? (...while continuing to publish about and do research on them). Do you think you're more clever than scientists, who somehow haven't noticed that there are long term climate cycles in their published results, despite still managing to write extensively about them? It must be a bizarre mindset which leads to your arrogance. 1. http://www.grida.no/publications/other/ipcc_tar/?src=/climate/ipcc_tar/wg1/fig3-2.htm http://www.grida.no/publications/other/ipcc_tar/?src=/climat... 2. http://www.sciencemag.org/content/341/6145/486 http://www.sciencemag.org/content/341/6145/486
      • ctdonath 13y ago