Let me now address the problem of
Poor Temperature Station Quality
Many temperature stations in the U.S. are located near buildings, in parking lots, or close to heat sources. Anthony Watts and his team has shown that most of the current stations in the US Historical Climatology Network would be ranked "poor" by NOAA's own standards, with error uncertainties up to 5 degrees C.
Did such poor station quality exaggerate the estimates of global warming? We've studied this issue, and our preliminary answer is no.
The Berkeley Earth analysis shows that over the past 50 years the poor stations in the U.S. network do not show greater warming than do the good stations.
Thus, although poor station quality might affect absolute temperature, it does not appear to affect trends, and for global warming estimates, the trend is what is important
Our key caveat is that our results are preliminary and have not yet been published in a peer reviewed journal. We have begun that process of submitting a paper to the Bulletin of the American Meteorological Society, and we are preparing several additional papers for publication elsewhere.
NOAA has already published a similar conclusion – that station quality bias did not affect estimates of global warming – -- based on a smaller set of stations, and Anthony Anthony Watts and his team have a paper submitted, which is in late stage peer review, using over 1000 stations, but it has not yet been accepted for publication and I am not at liberty to discuss their conclusions and how they might differ. We have looked only at average temperature changes, and additional data needs to be studied, to look at (for example) changes in maximum and minimum temperatures.
In fact, in our preliminary analysis the good stations report more warming in the U.S. than the poor stations by 0.009 ± 0.009 degrees per decade, opposite to what might be expected, but also consistent with zero. We are currently checking these results and performing the calculation in several different ways. But we are consistently finding that there is no enhancement of global warming trends due to the inclusion of the poorly ranked US stations.
Berkeley Earth hopes to complete its analysis including systematic bias avoidance in the next few weeks. We are now studying new approaches to reducing biases from:
1. Urban heat island effects. Some stations in cities show more rapid warming than do stations in rural areas.
2. Time of observation bias. When the time of recording temperature is changed, stations will typically show different mean temperatures than they did previously. This is sometimes corrected in the processes used by existing groups. But this cannot be done easily for remote stations or those that do not report times of observations.
3. Station moves. If a station is relocated, this can cause a "jump" in its temperatures. This is typically corrected in the adjustment process used by other groups. Is the correction introducing another bias? The corrections are sometimes done by hand, making replication difficult.
4. Change of instrumentation. When thermometer type is changed, there is often an offset introduced, which must be corrected.
Potential Legislation
I was asked what legislation could advance our knowledge of climate change. After some consideration, I felt that the creation of a Climate Advanced Research Project Agency, or Climate-ARPA, could help.
Without the efforts of Anthony Watts and his team, we would have only a series of anecdotal images of poor temperature stations, and we would not be able to evaluate the integrity of the data
This is a case in which scientists receiving no government funding did work crucial to understanding climate change. Similarly for the work done by Steve McIntyre. Their "amateur" science is not amateur in quality; it is true science, conducted with integrity and high standards.
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14 Comments
Add CommentDoes anybody have information on the median coefficient of thermal expansion of the earths tectonic plates?
Reply | Report Abuse | Link to thisPerhaps this could explain the recent surge in plate related catastrophic events.
I don’t have much issue that measured “Global Warming” is happening but I’d like clarification of what exactly is being measured.
Reply | Report Abuse | Link to thisIt seems to be air temperature near the Earth’s surface – but at what height, or is it the actual surface? Also it seems that some stations are located in the ocean, some even are from water intakes of passing ships. Water has a far different heat content from air and even its close proximity alters measured air temperatures. Of course, where measurements near ice, particularly melting ice, are concerned, eg Greenland, that problem is exaggerated. I imagine some kind of data-weighting is done. Perhaps Richard Muller could respond.
The problem is of particular concern when instrumental measurements are not available and proxies have to be used for these past times, and quite often they refer to soil, lake or ocean temperatures.
Of more concern is the ascription of this temperature rise to AGW. For example, the 30 year period, 1910 to 1940 – a “gold standard” non-AGW period - produced a 0.5C rise, yet the alleged AGW 60 year period from 1950 to 2010 produced a slower rise of 0.6C. How can that be!?
(One should also note that Greenland had about 50% faster temperature rise in the period 1920 to 1930 than in 1995 to 2005).
If one is anxious that CO2 is the cause of Global Warming via its greenhouse absorption, one can actually check that this is minimal now, using spectrophotometric measurements eg Gebbie et al 1951. These show that temperature rise due to CO2, let alone AGW CO2, cannot be more than 0.2C since then. (Even a 10-fold increase in CO2 would lead to less than 0.4C increase above that of 1951). I don’t think the IPCC even refers to such scientific data that would establish quantitative greenhouse effects; correct me if otherwise. It appears that climatologists and the IPCC assume that the temperature rise is due to CO2, then calculate further temperature rises from increasing CO2 levels (which I agree are happening). They compound this error further by extrapolating, usually linearly – forget about the Beer-Lambert Law! – to derive future temperature rises.
Overall, particularly when the period 1910-1940 are also considered, global temperatures are rising due to something other than greenhouse gas rises.
Ah yes ... just send us more money and we will study it further.
Reply | Report Abuse | Link to thisHow about we just concentrate on using energy wisely and stop the overemphasis on global warming? Regardless of whether or not CO2 is a problem, greenhouse gases will be efficiently reduced as a happy byproduct.
By wise use of energy, I mean produce and use it efficiently and economically.
Is not this bureaucrat-funded scientist doing what he had been paid to do? He certainly jumps through the hoops with ease - we are impressed by his ability really talented circus dog. Or, as George Orwell commented, the really well trained dog doesn't have to be told to jump through the hoops - he knows when he is supposed to please his masters.
Reply | Report Abuse | Link to thisClimate change skeptics are a dying breed.
Reply | Report Abuse | Link to thisI believe in climate change. Afterall, we are only a few thousand years out of the last glacial maximum which peaked about 25,000 years ago. Which means that the earth is getting warmer...wow...what a concept. And as the earth warms, poikilotherms' metabolism increases and yes, C02 increases. And we produce 27 billion tons of C02 into an atmosphere that already has 3,600 billion tons of C02.
Reply | Report Abuse | Link to thisI don't see why the method presented by the authors avoid the fundamental problems of previous analysis. Many stations around the world, can be providing an increase of temperatures for reasons not at all related with global warming and far more parsimonious (chiefly the approach of urbanization to stations which use to be in rural settings - see http://videolectures.net/kolokviji_singer_nnha/). By choosing "randomly from the complete set of 39,028 stations", those ones subject to such interferences are kept in the analytical pool and interfering in the same way than if the whole dataset would be used (that is the aim of a random selection). If the authors wanted to avoid such known bias, they would have no other choice than a non-random exclusion of all stations that could be affected by non-global warming interferences (for instance, leaving only stations in rural areas and national parks, and in which immediate environment -e.g. within a radius of 5 kilometers- was kept basically unaltered)
Reply | Report Abuse | Link to thisThe tectonic plates break up the earth's crust in a fair number of pieces. The tectonic activity is largely driven by convective flows inside the mantle.
Reply | Report Abuse | Link to thisThe earth's crust is a poor conductor of heat generally speaking. The current surface warming is by no means sufficient to alter the crust in any meaningful way.
The best way to think about that is paradoxically permafrost. In some places in Siberia the permafrost goes down to some 1400 meters.
It is estimated that this freezing took hundreds of thousands of years during the glacial cycles in the last 3 million years in the northern hemisphere.
The summer sunshine warms the surface and melts some of the permafrost down to about 4 meters maximum. The permafrost comes back during the followong winter.
A simple calculation would show that if you stopped all freezing during the wintertime it would take 400 years to melt all the permafrost. This is very simplistic.
The crust on land, i.e. the tectonic plates are between 10 to 30 kilometers thick. This should give you some idea how long it would take for global warming to increase the temperature of the crust by even a very small fraction of a degree.
There is no evidence at all that the current surface warming has or will in the foreseeable future affect the tectonic plates in any way so that it will change tectonic activity.
Mostly ,I think, some parts of the global warming get confused rather badly and mostly due to the complexity of the problem.
Reply | Report Abuse | Link to thisThe average surface temperature is one thing, the ocean upper layers temperature is another thing alltogether.
The warming caused by CO2 is one thing, warming caused by extra water vapor in the air is another thing and warming caused by non-anthropogenic factors such as solar heating variation is yet another thing.
Land surface temperatures is what most concerns us because we mostly live on the land. We think that the ocean is warming as a result of surface warming and that adds water vapor which has stronger warming potential than CO2 all by itself. In other words water vapor is a gas and it is a fairly strong greenhouse gas.
The story is roughly CO2 warms the planet's (prevents natural radiative cooling) atmosphere close to the surface. This in turn evaporates more water on land AND warms the top few meters of the ocean. This in turn increases evaporation which in turn causes more warming etc.
The really hard part is to distinguish between naturally caused warming such as perhaps more sunshine and warming caused by the extra fossil fuel CO2.
Nobody claims that the natural causes of warming and or cooling have suddenly ceased to exist. They carry on in their good old usual fashion.
We do claim that the extra CO2 is providing additional warming and that includes other feedbacks such as more water vapor and hence even more warming.
It is the combined effects of fossil fuel CO2 i.e. increased CO2 and any derivative warming caused by that which we call AGW.
The period from 1910 10 1940 was one of warming. It is said that this could not be caused by AGW because we did not then use fossil fuels in the quantities we use today. But you can rest assured that some of the warming was caused by AGW even then. It is just that the natural causes overwhelmed the AGW cause so that you could not clearly measure the human caused part of the warming but it was there nevertheless.
Reply | Report Abuse | Link to thisSo IF the period of 1950 to 2010 only produced 0.6 degrees of warming it could very well be that some natural warming factors were absent and most of the warming was caused by CO2 and it's feedbacks.
The best example of that is mount Pinatubo. It exploded in 199x and caused some cooling during the next couple of years. This is a natural cause of global cooling. But after that cooling the earth resumed it's warming as if nothing happened.That warming was largely caused by AGW unless you can come up with a natural cause in which case you would win the nobel prize.
Actually we just added 30 billion tons of CO2 measured by mass in 2010 and I do not think that the atmosphere holds 3600 billion tons of CO2 more like 3000. Check the figures.
Reply | Report Abuse | Link to thisSo we just added another 1 percent of CO2 by mass. That means we will have 6000 billion tons of CO2 by mass by the year 2111 if there is no compounding and if the planet does not produce even more CO2 from the warming we have caused so far.
The author clearly stated that the exclusion of urban center weather stations only produced a difference of 0.009 degrees. This has been done many times by now.
Reply | Report Abuse | Link to thisThe fact is that no matter how you look at the data the global average temperature increase is a fact of life. You may dispute the actual increase over a few thousands of a degree but the increase of 1.2 degrees is there. There are 1200 thousands of a degree in 1.2 degrees. You can have the 9 and call that the urban heat island effect. But it does not make a particle of difference.
Case closed.
umm...El Nino. Where's my prize?
Reply | Report Abuse | Link to thiswell jsobry, the case might be closed for you. I am far from convinced that the huge increase on urbanization population, energy production and transport on the last decades had great impact on temperatures a global level, but very little on the temperatures on the local level.
Reply | Report Abuse | Link to thisAnd in addition of not being convinced that we have a overall and consistent trend on the increases of global temperatures, I am not convinced that:
1st) such hypothetical change is causing any of the floodings, heat/cold waves, etc we see frequently being attributed to global change (if -big IF- happening, perhaps global warming would actually be not that bad - see http://video.google.com/videoplay?docid=-5576670191369613647)
2nd) if existent, they are due to human activity (let alone to CO2. Again, please check the video above before replying to this message)