David Rodale
Muse
- Joined
- Jun 29, 2006
- Messages
- 680
Exactly. So I think if Watts were on to something, he should be able to show some serious problems with the data, and he hasn't been able to do that. The pictures alone just can't be used to conclude that there are serious problems with the surface data.
It would be best if you'd change the subject before digging a hole you can't get out of. None of you have researched this, but instead raise your hands and waive furiously.
The WMO has internationally recognized standards for siting of surface stations. The pictures on Watts website document clearly differentiate those that meet the standards from those that do not.
There are numerous examples demonstrating statements such as yours is not supported by any empirical data. The "studies" your side provided are nothing but speculation or single-site evaluation. To say that wind evens out the UHI effect is ludicrous to be generous.
There are many details not addressed thus far, but one very simple reason why there are so many thermometers shown attached to roof tops, sides of buildings, parking lots, sidewalks etc., is because the cabling requirements do not allow for long distances to the data collection source.
We can go into more detail on other issues which you've likely never considered, but for now, dwell on these:
Detecting urbanization effects on surface and subsurface
thermal environment — A case study of Osaka
A B S T R A C T
Article history:
Tremendous efforts have been devoted to improve our understanding of the anthropogenic effects on the atmospheric temperature change. In comparison, little has been done in the study
of the human impacts on the subsurface thermal environment. The objective of this study is to analyze surface air temperature records and borehole subsurface temperature records for a better understanding of the urban heat island effects across the ground surface. The annual surface air
temperature time series from six meteorological stations and six deep borehole temperature profiles of high qualities show that Osaka has been undergoing excess warming since late 19th century. The mean warming rate in Osaka surface air temperature is about 2.0 °C/100a over the
period from 1883 to 2006, at least half of which can be attributed to the urban heat island effects.
However, this surface air temperature warming is not as strong as the ground warming recorded in the subsurface temperature profiles. The surface temperature anomaly from the Osaka meteorological record can only account for part of the temperature anomaly recorded in the
borehole temperature profiles. Surface air temperature is conventionally measured around 1.5m above the ground; whereas borehole temperatures are measured from rocks in the subsurface.
Heat conduction in the subsurface ismuch less efficient than the heat convection of the air above the groundsurface.Therefore, the anthropogenic thermalimpacts onthe subsurface can bemore
persistent and profound than the impacts on the atmosphere. This study suggests that the surface air temperature records alone might underestimate the full extent of urban heat island
effects on the subsurface environment.
“The Osaka station shows a warming trend of 1.99 °C/100a over the 124 year period from 1883 to 2006, more than triple the 20th century global warming rate 0.6 °C/100a (IPCC, 2001). The anomalous urban warming is consistently recorded in the
records from the nearby urban/suburban stations, of which the warming rates are 2.24 °C/100a for Kyoto, 1.45 °C/100a for Kobe, and 1.96 °C/100a for Nara, respectively. In comparison, the warming rates recorded in the two rural stations are more diverse. Over its 55-year life span, the Tsurugisan station showed a warming rate of 0.47 °C/100a which is slightly lower than the global average; whereas the 82-year Ibukiyama record showed a 1.60 °C/100a warming rate that is much greater than the global average.”
“The JMA (JMA, 2006) cautions that its regional estimate might be not entirely free of urbanization perturbation. Based on the records from the urban stations around Osaka and the JMA regional estimate, a conservative estimate of the urban heat island effects in Osaka would be in the range of 1–2 °C/ 100a. This estimate agrees in general with the early analysis of Kato (1996). Based on principal component score analysis of monthly mean temperature data for the period from 1920 to 1992 from 51 meteorological stations in Japan, Kato suggests that the maximum urban effects with a population of over 100,000 in 1993 were 1.0–2.5 °C/100a in Japan (Kato, 1996).”
MICROCLIMATE EXPOSURES OF SURFACE-BASED WEATHER STATIONS
The USHCN sites with good temperature exposure characteristics (i.e., meet all or almost all of the WMO standards) are in the minority in the set discussed in this paper. If the majority
of observing sites elsewhere have similar problems
to those in eastern Colorado, a significant number
will have nonrepresentative exposure features.
Anthropogenic heat island at Barrow, Alaska, during winter: 2001–2005
The village of Barrow (71_N latitude) is the largest native community in the Arctic,
with a population of approximately 4500 people. Situated on the coast of the Arctic Ocean in northernmost Alaska, the area is entirely underlain by permafrost. Although most
supplies must be imported, Barrow relies on local natural gas fields to meet all energy
requirements for building heat and electrical power generation. This energy eventually
dissipates into the atmosphere, and can be detected as a pronounced urban heat island
(UHI) in winter. Since 2001, a 150 km2 area in and around Barrow has been monitored using _70 data loggers recording air temperature at hourly intervals. The mean daily temperature of the urban and rural areas is calculated using a representative sample of core sites, and the UHI magnitude (MUHI) is calculated as the difference in the group averages. The MUHI is most pronounced in winter months (December–March), with temperatures in the urban area averaging 2_C warmer than in the surrounding tundra and occasionally exceeding 6_C.
Quantifying the influence of anthropogenic surface processes and
inhomogeneities on gridded global climate data
Local land surface modification and variations in data quality affect temperature
trends in surface-measured data. Such effects are considered extraneous for the purpose of measuring climate change, and providers of climate data must develop adjustments to filter them out. If done correctly, temperature trends in climate data should be uncorrelated with socioeconomic variables that determine these extraneous factors. This hypothesis can be tested, which is the main aim of this paper. Using a new database for all available land-based grid cells around the world we test the null hypothesis that the spatial pattern of temperature trends in a widely used gridded climate data set is independent of socioeconomic determinants of surface processes and data inhomogeneities. The hypothesis is strongly rejected (P = 7.1 _ 10_14), indicating that extraneous (nonclimatic) signals contaminate gridded climate data. The patterns of contamination are detectable in both rich and poor countries and are relatively stronger in countries where real income is growing. We apply a battery of model specification tests to rule out spurious correlations and endogeneity bias. We conclude that the data contamination likely leads to an overstatement of actual trends over land. Using the regression model to filter the extraneous, nonclimatic effects reduces the estimated 1980–2002 global average temperature trend over land by about half.
How much Estimation is too much Estimation?



