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Between the two of them, they are the entirety of the satellite global atmospheric temperature data sets. If you run a linear regression on the TLT (total lower

Between the two of them, they are the entirety of the satellite global atmospheric temperature data sets. If you run a linear regression on the TLT (total lower tropospheric) data from 1997 to current, you'll get a zero trend. If you allow for their level of confidence, you get a zero trend from 1994. These are two separate organizations, who's data (with UAH's 6.0 update) is within .2C of each other. UAH is University of Alabama in Huntsville in partnership with NASA. RSS is a private atmospheric research company. Both their data sets start in 1979. Without discounting their data, what theory of anthropogenic global warming accounts for this length of no warming during the period where 1/3rd of all man made CO2 was released into the atmosphere? I'm extremely curious and have had no luck getting an answer anywhere. The data is easy to find, but I can link it if you want to run it yourself. The UAH 6.0 data is still in Beta, but NASA started accounting for loss of orbit and are working on an updated record.

mikeash 11y ago
I'm not familiar enough with the data to say what the explanation might be. These folks are, though: http://www.le-telegraphe.ch/docus/warming.pdf http://www.le-telegraphe.ch/docus/warming.pdf So if you're interested in the latest, reading that is probably a good start. It looks to me like there's a lot more than just satellite data to examine.
- merpnderp 11y ago
  That study has not been well received in the climate change community. HADCRUT4 is already the de facto standard for land/sea based climate stations/buoys, and this does some questionable things with sea water and the land stations. And the HADCRUT4 people wave off the satellite data with "they don't adjust for satellite drift or sensor degradation", but that's all NASA/UAH and RSS do with the data. But even so, their data shows a pause going back 13 years. And this is exactly what I find everywhere when looking for info about the satellite data. Not an explanation of what it means, but attacks on its veracity. Which goes back to my original point or attacking the questioner instead of explaining what the satellite data means. Personally I find it hard to believe that a mishmash of thousands of types of land based weather stations, in thousands of different microclimates and variable conditions, could possible be superior to simply measuring the total energy released by a slice of 75% of the atmosphere.
  - mikeash 11y ago
    I sure hope you're not referring to my posts when you talk about "attacks," because "I don't really know but here's a paper that looks good" is about as far from that as you can get.
    - merpnderp 11y ago
      Absolutely not. Sorry for the confusion. I just can't find any papers on why the satellite data is wrong other than hand waving about how peer reviewed research into bias correction is wrong. And I also can't find anything explaining what the satellite data means. That NOAA paper you linked has some interesting issues. But even if it is correct (it's probably not), it shows a low sensitivity to CO2.
      - mikeash 11y ago
        I wasn't sure, so I'm glad I asked instead of assuming! Anyway, I'm afraid I can't really help, I just don't know enough about all the various issues involved. The interpretation of temperature data seems to boil down to a whole bunch of "it's complicated." I lean heavily towards the people who say "it's complicated, but when you analyze it properly it shows warming" over the people who say "the data shows there is no warming" just because the latter tend to see calibration as a ploy and tend not to be well versed in the actual science, whereas the former is usually from people who study this stuff for a living. I will certainly admit that this is not the most solid approach, but it seems to be about the best a person can do without dedicating a significant part of your life to studying it in depth.
        merpnderp 11y ago
        You are absolutely correct. It is complicated. And given a healthy dose of scientific skepticism, there is no good way to know for sure right now. For instance that NOAA study you linked uses UAH satellite tropospheric data to fill in for missing grounds stations, which is highly controversial (because how does that work), and even more so over the poles, since UAH data their is poor and scattered. Then the .12C difference between ship and buoy sea surface temps seems like is too convenient. I have a feeling that if they were honest with their confidence intervals, they'd be larger than the possible signal. After working through tons of this stuff, reading papers, replicating the math where I can (hard to get source data, and harder to get actual algorithms), I'm left with "who knows?" But the satellite data is clear (and is the only contiguous pole to pole measurement of the atmosphere we have). No warming for over 20 years.

mikeash 11y ago

I'm not familiar enough with the data to say what the explanation might be. These folks are, though: http://www.le-telegraphe.ch/docus/warming.pdf http://www.le-telegraphe.ch/docus/warming.pdf So if you're interested in the latest, reading that is probably a good start. It looks to me like there's a lot more than just satellite data to examine.

merpnderp 11y ago
That study has not been well received in the climate change community. HADCRUT4 is already the de facto standard for land/sea based climate stations/buoys, and this does some questionable things with sea water and the land stations. And the HADCRUT4 people wave off the satellite data with "they don't adjust for satellite drift or sensor degradation", but that's all NASA/UAH and RSS do with the data. But even so, their data shows a pause going back 13 years. And this is exactly what I find everywhere when looking for info about the satellite data. Not an explanation of what it means, but attacks on its veracity. Which goes back to my original point or attacking the questioner instead of explaining what the satellite data means. Personally I find it hard to believe that a mishmash of thousands of types of land based weather stations, in thousands of different microclimates and variable conditions, could possible be superior to simply measuring the total energy released by a slice of 75% of the atmosphere.
- mikeash 11y ago
  I sure hope you're not referring to my posts when you talk about "attacks," because "I don't really know but here's a paper that looks good" is about as far from that as you can get.
  - merpnderp 11y ago
    Absolutely not. Sorry for the confusion. I just can't find any papers on why the satellite data is wrong other than hand waving about how peer reviewed research into bias correction is wrong. And I also can't find anything explaining what the satellite data means. That NOAA paper you linked has some interesting issues. But even if it is correct (it's probably not), it shows a low sensitivity to CO2.
    - mikeash 11y ago
      I wasn't sure, so I'm glad I asked instead of assuming! Anyway, I'm afraid I can't really help, I just don't know enough about all the various issues involved. The interpretation of temperature data seems to boil down to a whole bunch of "it's complicated." I lean heavily towards the people who say "it's complicated, but when you analyze it properly it shows warming" over the people who say "the data shows there is no warming" just because the latter tend to see calibration as a ploy and tend not to be well versed in the actual science, whereas the former is usually from people who study this stuff for a living. I will certainly admit that this is not the most solid approach, but it seems to be about the best a person can do without dedicating a significant part of your life to studying it in depth.
      - merpnderp 11y ago
        You are absolutely correct. It is complicated. And given a healthy dose of scientific skepticism, there is no good way to know for sure right now. For instance that NOAA study you linked uses UAH satellite tropospheric data to fill in for missing grounds stations, which is highly controversial (because how does that work), and even more so over the poles, since UAH data their is poor and scattered. Then the .12C difference between ship and buoy sea surface temps seems like is too convenient. I have a feeling that if they were honest with their confidence intervals, they'd be larger than the possible signal. After working through tons of this stuff, reading papers, replicating the math where I can (hard to get source data, and harder to get actual algorithms), I'm left with "who knows?" But the satellite data is clear (and is the only contiguous pole to pole measurement of the atmosphere we have). No warming for over 20 years.