Some questions occurred to me: Are the MMTS systems automatic recording, or do the maximum and minimum readings have to be manually recorded? If they are manually recorded and the attendant misses a day, there is no way to tell which day the maximum and minimum readings represent. The deployment of the MMTS system began in the mid-80’s. How far along is that deployment and what effect does that have on temperature records?

REPLY: The early MMTS display had no memory, while the newer display model, the “Nimbus” has a 5 day hi/lo memory I believe. So yes, it’s possible in the early models (and many are still in service) to miss a day. The deplayment of equipment cna be seen here:

http://www.surfacestations.org/images/USHCN_equip.gif

- Anthony

That’s how heat sinks work. The more heat, the more heat sink effect.

The flip side is that if a serious cool phase sets in, the effect “undoes” itself an may produce an exaggerated cooling trend.

It would be ironic if they fix the problems just as a cool phase begins so there is a normal cooling trend, but they never account for the artificial warming that proceeded it.

Winter months are nearly “the same”. But summer months are “more” warmer/hotter due to the station’s surroundings. The parking lot itself but I think far more the car-ovens (they warm up to 60-70 deg Celcius – 122-140 F) contribute to the warmness/hotness of the area and its vicinity. Let’s make 12 charts with annual mean temperature for the 12 months (for the years period). Draw the trend lines and compare them on joint chart. I am very curious were the “warming culprit” hid in the data.

I would also make another assesment. I’d select all July days with fully sunny days with 4 types of wind (null, gentle, light, small strong) and two directions (1) from the lot and 2) from a “cooling” direction against the lot). I’d be able to check how far the temperatures differ with or without “warming/cooling” winds. In other words I could find out how much the lot-pans contribute to the temp readouts.

The best method would be to put for a week in neutral place a similar station plus wind meter and match the results according to wind direction and strength. But assuming yearly percentage of wind directions for the given area would suffice.

What is it with the siting of these screens that they insist on having a sidewalk leading up to them?

It’s a “don’t walk on the grass” thing. You can see the path in the aerial view and of course the shrubbery is needed to make the site less unsightly. And don’t worry, the tree will correct for the asphalt eventually (grin).

it is becoming clearer to me that looking for a clean climate change signal in surface data is a complex excercise in uncertainty.

You are rather generous here. I would have chosen the phrase “an exercise in futility.”

REPLY: It’s in the high 20’s I believe, I’m about ready to do another compiliation and I’ll report on it soon.

But what if there was a change in winds pattern or cloudness over the place from 40s? Or droughts which resulted in lawn sprinkling limits?

Wouldn’t it be advisable to select, let’s assume, 5 such locations and perform meticulous research taking into consideration all possible factors? I wonder how the Annual Mean Temperature would look like then? Perhaps such research would reveal a practical method how to deal with such placed stations which in turn would enable to correct more scientifically all the station results without resorting to population densities?

Despite all of the localized warming effects, it appears from the GISS graph that the site has cooled significantly since Dr. Hansen made his 1988 speech to Congress forecasting imminent and catastrophic warming.

http://www.hprcc.unl.edu/products/maps/acis/mrcc/YearTDeptMRCC.png