Isn’t there someone credible in the climate field that can really try to sort out the increasing divergence of satellite vs. surface temperature records? I know there are critical studies to be done on the effect of global warming on acne, but I would think actually having an idea of how much the world is currently warming might be an important fact in the science of global warming.
The problem is that surface temperature records are showing a lot more warming than satellite records. This is a screen cap. from Global Warming at a Glance on JunkScience.com. The numbers in red are anomalies, and represent deviations from a arbitrary period whose average is set to zero (this period is different for the different metrics). Because the absolute values of the anamolies are not directly comparable, look at the rankings instead:
Here is the connundrum — the two surface records (GISTEMP and Hadley CRUT3) showed May of 2009 as the fifth hottest in over a century of readings. The two satellite records showed it as only the 16th hottest in 31 years of satellite records. It is hard to call something settled science when even a basic question like “was last month hotter or colder than average” can’t be answered with authority.
Skeptics have their answer, which have been shown on this site multiple times. Much of the surface temperature record is subject to site location biases, urban warming effects, and huge gaps in coverage. Moreover, instrumentation changes over time have introduced biases and the GISS and Hadley Center have both added “correction” factors of dubious quality that they refuse to release the detailed methodology or source code behind.
There are a lot of good reasons to support modern satellite measurement. In fact, satellite measurement has taken over many major climate monitoring functions, such as measurement of arctic ice extent and solar irradiance. Temperature measurement is the one exception. One is left with a suspicion that the only barrier to acceptance of the satellite records is that alarmists don’t like the answer they are giving.
If satellite records have some fundamental problem that exceeds those documented in the surface temperature record, then it is time to come forward with the analysis or else suck it up and accept them as a superior measurement source.
Postscript: It is possible to compare the absolute values of the anamolies if the averages are adjusted to the same zero for the same period. When I did so, to compare UAH and Hadley CRUT3, I found the Hadley anamoly had to be reduced by about 0.1C to get them on the same basis. This implies Hadley is reading about 0.2C more warming over the last 20-25 years, or about 0.1C/decade.
The satellite records are spliced togther from multiple satellites. The MSU groups have published their splicing methods and the differences appear to be the primary reason for the trend different between RSS and UAH.
However, I am sceptical of these ad hoc methods for fixing data problems because of the confirmation bias in the process because methods are evaluated by their abilty to produce plausible results – i.e. methods that produce matches to the surface record are deemed correct and those that do not match the surface record are quietly discarded as “obviously wrong”.
This means we should expect the satellite records to diverage during the lifetime of a single satellite. The records will be synched up again when a new satellite is launched which and the alarmists will insist that it was ‘short term weather variations’.
Bottom line, I would not put too much faith in long term satellite trends.
It seems if the owners of a data set believe in climate change they obtain warming trends and if the owners of a data set do not believe in climate change they do not see warming. How do we get an objective archiver and honest broker for climate data?
We know that 90% of the US surface sites fail to meet basic scientific standards. We know that our climate scientists never bothered to check the quality of their thermometers. This tells us that their commitment to quality is abysmal. We also know that the US sites are better than most in the rest of the world. Accordingly, we can conclude that no rational person would ever rely on the surface numbers because the thermometers are bad and the scientists aren’t competent.
[I take it as a given that competent scientists routinely calibrate their instruments and check to see that they meet basic scientific standards.]
The surface records are crap. Ignore them.
Your wrong to say the climage scientists never check the quality of their thermometers. They do if the trend in the data does not follow the expected trend. That’s whe when the Argo bouys showed cooling, they checked everything and were eventually able to make corrections that subsequently showed no heating. I again say, the holders and archivers of the climate data base need an objective custodian whose only passion is accuracy and completeness.
Regarding the divergence of different temperature records, I believe that Mr. Meyer incorrectly advises us to focus on the ranking: such a focus overstates the divergence. For example, the satellite records show May to be 16th out of 31 while surface-based records show the month to be 5th out of 160 (or 130). If satellite records had started 160 years ago, May 2009 likely would have been 16th (or maybe 19th) out of 160 because GMT rose since the Little Ice Age.
Whether the various temperature records confirm each other or show divergence depends quite a bit on starting & ending points and the methodology used to compare.
I prefer to look at both UAH MSU and RSS MSU, even if they are both satellite based. One is managed by skeptics and the other is managed by GW pessimists; so they provide a good check on each other. Moreover, the collegial relationship between the two is commendable and remarkable in the politicized climate debate. It would be great to have what Sean Wise desires: an objective custodian to hold and archive climate data bases. However, that is not going to happen in the foreseeable future, so looking at multiple perspectives appears to be the next best alternative. (By the way, I do keep my own index of a global temperature based on sites in Greenland, Antarctica, and rural U.S. sites – sites where I feel good about minimal UHI and local siting issues. And my impression is that world temperatures were just as high 65 or 75 years ago as they are now.)
For the record, it is better to call GISTEMP a surface-based record rather than a surface record. GISTEMP uses satellite data for temperatures over oceans, but such a statement is a gross simplification. I tried to follow the algorithm by which it used satellite data, and terms such as “bizarre” and “absurd” and “awkward” came to my mind rather than “a pleasing blend of surface and satellite information.” Meanwhile, I cannot think of any scientific realm where credence is given to a record whose production is kept a secret and whose results are neither verifiable nor replicable. Although we should not be overly enamored with satellite estimates – for they have their issues, too – still, any alarms from surface records fail to cause me panic.
The satellite reports have been ‘adjusted’ at least 3 times, the last quite recently. Hard to say whether they are finished or whether they will need another tweak.
I have an Idea. Lets say you are a climatologist and you want (or need) a grant of some sort. What concept do you suppose will most likely get you that grant, gloom and doom man made global warming or data that shows a possible warming trend but further study is needed. I know this is drastically simplified but I think the idea may have merit.
The word is anomaly, not anamoly.
It appears that scientific “objectivity” is paralleling the lack of credibility with America’s concept of the rule of law. Race and social considerations now trump objective, understandable laws similiar to grants, fellowships, titles and Nobel awards trumping factual data. It’s become the “politics of pull” as Rand referred to current events.