Arstechnica Defends Junk Science (Or Tampering In California)
By Paul Homewood
There’s a long winded piece out on something called arstechnica (whatever that is), which attempts to defend the thoroughly discredited surface temperature datasets. It looks as if it might as well have been written by Gavin and his cronies.
It is full of errors and falsehoods, like:
- Sceptics say temperatures should never be adjusted – nobody I know argues this. What they do query are adjustments that cannot be explained by NOAA etc, and fly in the face of factual evidence.
- Ignoring the fact that NOAA, GISS and HADCRUT have all been adjusted in stages in recent years, with each miraculously adding to the warming trend
- Claiming that UHI has been proven not to affect global temperature trends, when there are many studies that show it does exist and is not being properly accounted for.
- Rubbishing satellite data.
- Ignoring the vast areas of the world not covered by measurements
But they show one interesting graph, apparently from BEST. Whilst showing the effect of TOBS, it also shows another chunk being added on for “homogenisation”, (the difference between the blue and green curves).
The only justification they can offer for this is:
Some weather station changes are pretty straight-forward. The desire for weather information at new airports around the 1940s led to station moves. Some of these stations had been set up on the roofs of post office buildings and later found themselves in an open environment on the edge of town. Looking at the temperature records, you might see a sudden and consistent drop in temperatures by a couple of degrees.
It is true that the homogenisation process will pick this up, because it is a step change. However, what gets ignored is the fact that, over the decades, the new airport site goes from being little more than a grass field to a busy, tarmac covered airport, with jets flying in and out, and an urbanised environment with car parks, airport buildings etc. All of this will add to a growing UHI trend.
By the time this lot is accounted for, it is likely that the UHI effect is more than it was in the city seventy years ago. In the meantime, the original station move is adjusted for, but the UHI effect at the airport is not.
In reality, of course, the above graph does not show any big adjustments in the 1940’s and 50’s, when most station moves to airports took place. Instead, they seem to suddenly take off around the 1990’s.
San Diego’s International Airport, Lindbergh Field, is a case in point, which shows that homogenisation is failing to account for UHI. It is the busiest single runway commercial airport in the US, handling 18 million passengers a year. Lindbergh Field was actually built in 1929, and the station metadata shows that the temperature station has been pretty much in the same spot ever since.
It does not really take a genius to work out that the UHI effect will have grown substantially there over the years.
Yet when we check GHCN we find that, far from allowing for UHI, they have actually done the opposite and cooled the past! (The top, red graph is unadjusted, and yellow adjusted. The bottom graph shows the actual adjustments).
The cooling adjustments kick in in 1941, since when 0.9C has been effectively added to current temperatures (or deducted from old ones). This clearly is a nonsense.
So, what has this been based on? When we look at some of the surrounding stations, we find that matters get even worse.
When we check the GISS list of GHCN stations near to San Diego, the only rural site with up to date records (in fact, 2014) is Cuyamaca. If you are going to homogenise, it should only be done against reliable, high quality rural sites.
Incredibly, when we check out Cuyamaca, we find that it has been even more heavily adjusted up than San Diego.
On what basis, therefore, have Cuyamaca and San Diego been adjusted up? The clue lies in that GISS list.
All of the other rural sites disappeared years ago, and current temperature measurements are dominated by Los Angeles sites.
Like the International Airport there:
Or in the heart of the city of Pasadena.
As more and more rural stations disappear, the few good stations left will be homogenised up to the UHI affected city and airport sites, rather than the other way around.
There is actually no secret about any of this. The fact that “scientists” can publish such garbage, and get away with it, is a disgrace.