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I've been developing an increasing interest in climate change lately, and I've also been digging into the numbers and arguments on both sides. Frankly, the cla

by jeremyt 11y ago

I've been developing an increasing interest in climate change lately, and I've also been digging into the numbers and arguments on both sides. Frankly, the claims made in this article are a bit ridiculous. To anyone with any kind of math or science background, the claim that one can accurately measure the temperature of the earth down to two decimal places is hubris. But it's even worse when one considers that the distribution of temperature recording stations isn't uniform, that large swaths of the earth have barely any coverage at all, and that the most accurate way of measuring temperature has only been available for the last couple of decades (satellite measurements). And I might add that the article above uses surface temperatures and not satellite measurements. In many of these temperature stations, temperatures are still recorded by hand, on a piece of paper, by observing a thermometer. One has to deal with different measurements made by different people and equipment as things are replaced or repaired. Additionally, lots of these temperature stations have had their recorded temperatures adjusted upward. I always wondered why, and I did some investigation and found out that it was because the temperature stations had been moved from an urban environment to a more rural environment. However, the measurements have not been subsequently adjusted down as those new environments urbanized. What we see is a ratchet effect, not in actual temperature but in observed temperature. What's the upshot? The supposed 0.02 increase in temperature is well within the margin of error for both the surface level temperature measurements and the estimation made in the upward temperature adjustments at many sites.

yuvadam 11y ago
So we're in the clear?
epoxyhockey 11y ago
Perhaps the scatter chart in the middle of the article may be more scientific and convincing? My household scale is accurate to 1 decimal place, is it hard to believe that the Japan Meteorological Agency is able to measure temperature to 2 decimals and account for margins of error? The scatter chart trend is most convincing.
- jeremyt 11y ago
  Please correct me if I'm wrong, but my understanding is that the scatter plot uses adjusted temperatures and not measured temperatures. Part of my anxiety over the temperature records is that many sites have been adjusted upwards at one time but not subsequently revisited based on changing conditions
cwal37 11y ago
Have you happened across this[1] (which ars sums up here[3]) in your comprehensive research on the topic? It's almost entirely about exactly what seems to be your big sticking point, that we're bad at measuring temperature, and the results aren't worthwhile as a result. This is something that absolutely consumes the scientists and technicians involved in taking these measurements, because they know it's going to catch heat no matter what. Here's a fairly comprehensive post[2] with numerous links to publications and explanations. Satellite vs. surface is mentioned explicitly near the bottom. [1]http://www.sciencemag.org/content/348/6242/1469 http://www.sciencemag.org/content/348/6242/1469 [2] http://www.skepticalscience.com/surface-temperature-measurements-advanced.htm http://www.skepticalscience.com/surface-temperature-measurem... [3] http://arstechnica.com/science/2015/06/updated-noaa-temperature-record-shows-little-global-warming-slowdown/ http://arstechnica.com/science/2015/06/updated-noaa-temperat...
- jeremyt 11y ago
  Appreciate the links. I will look them over.
- jeremyt 11y ago
  I dug a little deeper on your first link, and it appears that in order to come to a different conclusion, the scientists have just applied a different correction to the data... And, mind you, they're using extraordinarily unreliable ocean temperature measurements... Here's a key quote from a critique of the paper: "K15 have made some relatively minor changes to the bias correction methods, and the result is a large increase in the post-1998 trend. A. They added 0.12 oC to readings collected by buoys, ostensibly to make them comparable to readings collected by ships. As the authors note, buoy readings represent a rising fraction of observations over recent decades, so this boosts the apparent warming trend. B. They also gave buoy data extra weight in the computations. C. They also made adjustments to post-1941 data collected from ships, in particular a large cooling adjustment applied to readings over 1998-2000. Taken together these changes largely explain the enhanced trend over the past 15 years. So now everybody needs to decide if they think these adjustments are valid. Perhaps they are. The main problem for us observers is that other teams have looked at the same issues and come to different conclusions. And the post-1998 K15 data don’t match that from other independent sources, including weather satellites." To put it plainly: if the data doesn't fit, just make some convenient corrections and then suddenly it'll fit exactly what you want it to. I encourage you to read the whole critique: http://wattsupwiththat.com/2015/06/04/a-first-look-at-possible-artifacts-of-data-biases-in-the-recent-global-surface-warming-hiatus-by-karl-et-al-science-4-june-2015/ http://wattsupwiththat.com/2015/06/04/a-first-look-at-possib... The more I dig into this stuff the more I realize that the data, at least prior to satellite measurements, is just crap and needs to be discarded.

by jeremyt 11y ago

yuvadam 11y ago

So we're in the clear?

epoxyhockey 11y ago

Perhaps the scatter chart in the middle of the article may be more scientific and convincing? My household scale is accurate to 1 decimal place, is it hard to believe that the Japan Meteorological Agency is able to measure temperature to 2 decimals and account for margins of error? The scatter chart trend is most convincing.

jeremyt 11y ago
Please correct me if I'm wrong, but my understanding is that the scatter plot uses adjusted temperatures and not measured temperatures. Part of my anxiety over the temperature records is that many sites have been adjusted upwards at one time but not subsequently revisited based on changing conditions

cwal37 11y ago

Have you happened across this[1] (which ars sums up here[3]) in your comprehensive research on the topic? It's almost entirely about exactly what seems to be your big sticking point, that we're bad at measuring temperature, and the results aren't worthwhile as a result. This is something that absolutely consumes the scientists and technicians involved in taking these measurements, because they know it's going to catch heat no matter what. Here's a fairly comprehensive post[2] with numerous links to publications and explanations. Satellite vs. surface is mentioned explicitly near the bottom. [1]http://www.sciencemag.org/content/348/6242/1469 http://www.sciencemag.org/content/348/6242/1469 [2] http://www.skepticalscience.com/surface-temperature-measurements-advanced.htm http://www.skepticalscience.com/surface-temperature-measurem... [3] http://arstechnica.com/science/2015/06/updated-noaa-temperature-record-shows-little-global-warming-slowdown/ http://arstechnica.com/science/2015/06/updated-noaa-temperat...

jeremyt 11y ago
Appreciate the links. I will look them over.
jeremyt 11y ago
I dug a little deeper on your first link, and it appears that in order to come to a different conclusion, the scientists have just applied a different correction to the data... And, mind you, they're using extraordinarily unreliable ocean temperature measurements... Here's a key quote from a critique of the paper: "K15 have made some relatively minor changes to the bias correction methods, and the result is a large increase in the post-1998 trend. A. They added 0.12 oC to readings collected by buoys, ostensibly to make them comparable to readings collected by ships. As the authors note, buoy readings represent a rising fraction of observations over recent decades, so this boosts the apparent warming trend. B. They also gave buoy data extra weight in the computations. C. They also made adjustments to post-1941 data collected from ships, in particular a large cooling adjustment applied to readings over 1998-2000. Taken together these changes largely explain the enhanced trend over the past 15 years. So now everybody needs to decide if they think these adjustments are valid. Perhaps they are. The main problem for us observers is that other teams have looked at the same issues and come to different conclusions. And the post-1998 K15 data don’t match that from other independent sources, including weather satellites." To put it plainly: if the data doesn't fit, just make some convenient corrections and then suddenly it'll fit exactly what you want it to. I encourage you to read the whole critique: http://wattsupwiththat.com/2015/06/04/a-first-look-at-possible-artifacts-of-data-biases-in-the-recent-global-surface-warming-hiatus-by-karl-et-al-science-4-june-2015/ http://wattsupwiththat.com/2015/06/04/a-first-look-at-possib... The more I dig into this stuff the more I realize that the data, at least prior to satellite measurements, is just crap and needs to be discarded.