“As world celebrates Earth Hour, scientist finds global warming data has overestimated warming.”
Roy Spencer reports:
The supposed gold standard in surface temperature data is that produced by Univ. of East Anglia, the so-called CRUTem3 dataset. There has always been a lingering suspicion among skeptics that some portion of this IPCC official temperature record contains some level of residual spurious warming due to the urban heat island effect. Several published papers over the years have supported that suspicion.
The Urban Heat Island (UHI) effect is familiar to most people: towns and cities are typically warmer than surrounding rural areas due to the replacement of natural vegetation with manmade structures. If that effect increases over time at thermometer sites, there will be a spurious warming component to regional or global temperature trends computed from the data.
Here I will show based upon unadjusted International Surface Hourly (ISH) data archived at NCDC that the warming trend over the Northern Hemisphere, where virtually all of the thermometer data exist, is a function of population density at the thermometer site…
According to Muller –
“Urban areas are heavily overrepresented in the siting of temperature stations: less than 1% of the globe is urban but 27% of the Global Historical Climatology Network Monthly stations are located in cities with a population greater than 50000.”
How many more are, say, between 5000 and 50000?
http://notalotofpeopleknowthat.wordpress.com/2011/10/23/mullers-problem-with-uhi/
Saw this over on Watts Up With That. It just confirms what we’ve been surmising for years now.
Some warmist came up with the strawman argument that cities are only a very small part of the total landscape so the errors will also be very small. That is, until someone paying attention noted that the greatest number of thermometers are located in and around cities thus making the concentration of errors much higher. duh.
This is further evidence of the exaggeration of the effects of atmospheric CO2. In the next decade, the U.S. will start up its massive shale oil ICP extraction process. The current estimated yield from this 1.5 trillion barrel reserve is 750 billion barrels (42 gal/brl). Enough for us for the next 100 years. This plus our massive coal reserves makes us potentially the energy king of the world. Barring the lunatic fringe idea that CO2 needs to be completely curbed, we will have plenty of energy.