Do the locations of surface temperature stations create a bias in the temperature record?

Question

The argument that the surface record is biased is based upon photos taken of the temperature stations by Anthony Watts and little else, so it's hardly even worth discussing. However, I came upon a discussion by NASA GISS on the subject which I found interesting:

"Don't such concerns cast a shadow of doubt on the NOAA weather station data? Initially, perhaps, but not after the data have been carefully tested in several ways. First, Hansen's team (and others) finds good agreement of the weather station data with "proxy" data sets that are sensitive to surface temperature changes...Second, Hansen's team "cleans" the weather station data by finding and filtering out flawed data entries... The team uses satellite data to determine if a given station is in an urban or near-urban location. If so, then the team uses the nearest rural stations to determine the long-term trend at the urban site. If there are no rural neighbors, then Hansen's team throws out the urban station data."

Answer 1

Truly sorry your question got deleted...I loved my answer to it.  Instead of repeating it, I'll try this instead:

"It is commonly accepted that proxy indicators may contain nonclimatic trends. This is particularly true with tree-ring data (8), which were intensively used in the study by MBH98."

http://www.sciencemag.org/cgi/content/fu...

Answer 2

"...in 1997 there were concerns expressed by a National Research Council panel about the state of the climate measuring network.

In 1999, a U.S. National Research Council panel was commissioned to study the state of the U.S. climate observing systems and issued a report entitled: “Adequacy of Climate Observing Systems. National Academy Press”, online here  The panel was chaired by Dr. Tom Karl, director of the National Climatic Center, and Dr. James Hansen, lead climate researcher at NASA GISS. That panel concluded:

"The 1997 Conference on the World Climate Research Programme to the Third Conference of the Parties of the United Nations Framework Convention on Climate Change concluded that the ability to monitor the global climate was inadequate and deteriorating."

Yet, ten years later, even the most basic beginning of a recovery program has not been started. No online photographic database existed of the USHCN stations, and despite repeated requests from Dr. Robert A. Peilke Senior at CIRES the project has not been undertaken. Given the lack of movement on the part of NOAA and NCDC, Dr. Peilke also made requests of state climatologists to perform photographic site surveys. A couple responded, such as Roger Taylor in Oregon, and Dev Nyogi in Indiana, but many cited "costs" of such work to thier meager budgets as a reason not to perform surveys."

Answer 3

The surface record has a few more problems than poorly placed sites.

For starters the following equation has some issues.

T(average) = [T(max) + T(min)]/2.

"Our results also indicate that the 1.5 or 2 m minimum long term temperature trends over land are not the same as the minimum long term temperatures at other heights within the surface boundary layer (e.g., 9 m), even over relatively flat landscapes such as Oklahoma. For landscapes with more terrain relief, this difference is expected to be even larger. Therefore, the use of minimum temperatures at 1.5 or 2 m for interpreting climate system heat change is not appropriate. This means that the 1.5 to 2 m observations of minimum temperatures that are used as part of the analysis to assess climate system heat changes (e.g., such as used to construct Figure SPM-3 of the Intergovernmental Panel on Climate Change Parker lead to a greater long term temperature trend than would be found if higher heights within the surface boundary layer were used. Our exploration of near-surface lapse rate changes including wind effects should, therefore, be extended to longer-term time series as well as cover larger spatial areas.”

and the conclusion:

"From our papers (Pielke and Matsui 2005 and Lin et al. 2007), a conservative estimate of the warm bias resulting from measuring the temperature near the ground is around 0.21 C per decade (with the nightime T(min) contributing a large part of this bias) . Since land covers about 29% of the Earth’s surface (see), the warm bias due to this influence explains about 30% of the IPCC estimate of global warming. In other words, consideration of the bias in temperature would reduce the IPCC trend to about 0.14 degrees C per decade, still a warming, but not as large as indicated by the IPCC.

"

Answer 4

With the careful vetting of data NASA gathers, I can't see how there would be a bias. I would consider it accurate.