Wednesday, January 27, 2010

Global Temperature databases "seriously flawed and can no longer be trusted"

Anthony Watts of Watts Up With That and Joe D'Aleo of ICECAP released a comprehensive review of the historical Surface Temperature databases. Their assessment is that the data has been systematically cooked:
1. Instrumental temperature data for the pre-satellite era (1850-1980) have been so widely, systematically, and unidirectionally tampered with that it cannot be credibly asserted there has been any significant “global warming” in the 20th century.

2. All terrestrial surface-temperature databases exhibit very serious problems that render them useless for determining accurate long-term temperature trends.

3. All of the problems have skewed the data so as greatly to overstate observed warming both regionally and globally.

4. Global terrestrial temperature data are gravely compromised because more than three-quarters of the 6,000 stations that once existed are no longer reporting.

5. There has been a severe bias towards removing higher-altitude, higher-latitude, and rural stations, leading to a further serious overstatement of warming.

6. Contamination by urbanization, changes in land use, improper siting, and inadequately-calibrated instrument upgrades further overstates warming.

7. Numerous peer-reviewed papers in recent years have shown the overstatement of observed longer term warming is 30-50% from heat-island contamination alone.

8. Cherry-picking of observing sites combined with interpolation to vacant data grids may make heat-island bias greater than 50% of 20th-century warming.

9. In the oceans, data are missing and uncertainties are substantial. Comprehensive coverage has only been available since 2003, and shows no warming.

10. Satellite temperature monitoring has provided an alternative to terrestrial stations in compiling the global lower-troposphere temperature record. Their findings are increasingly diverging from the station-based constructions in a manner consistent with evidence of a warm bias in the surface temperature record.
Other than that, Mrs. Lincoln, how did you like the play?

This is 100 pages, and so is not a quick read. Much of this will be familiar to long time readers, and documents the numerous - and disturbing - problems with the historical climate databases. It's almost like someone was trying to manufacture a scientific consensus, or something.

With the recent complete unraveling of the last IPCC report (AR4), NASA had better hope that the Republicans don't gain control of one or both houses of Congress in the November elections. This paper is a primer for hours of photogenic, embarrassing questions from a Coal-State politician.


wolfwalker said...

To be fair, Jeff Masters over at Weather Underground has fired a serious shot at Anthony Watts's signature achievement, the survey of USHCN sensor stations that is described at He describes a paper that argues the bad placement of many USHCN stations has no significant effect on the overall temperature pattern.

Borepatch said...

Wolfwalker, there are likely all sorts of errors on the skeptic's side as well - no one side has a monopoly on truth.

However, there's an old saying that bad money drives out good money - when you debase the coinage, people expect debased coins (even if the coin is sound).

The problem for the warming side is that there are so many examples of them with their fingers on the scales that everything they publish is now under a cloud.

My opinion is that the only way to address this is to publish all data and algorithms. Transparency is the only thing that is likely to maintain credibility over time.

wolfwalker said...

I agree. None of the science is trustworthy anymore -- not the IPCC, and not the skeptics. Tear it all down and rebuild from the ground up.