You are taking this very seriously… so
while Anthony and his merry men are out and about please everyone consider the colors, mass and reflectivity of everything in the microclimate around the instruments… Black or dark Masses absorb… then re-radiate the heat… lighter colors reflect… but still absorb some heat… mirror glass on buildings may reflect the sun onto the instruments depending upon time of day, year, etc.

Watch out for refracted energy…

You have correctly indentified exhaust heat from AC units, Heaters, Boilers etc. – irrigaton, ponds, waterways and pools all usually reduce the local temperature.

I need to understand what is happening as I try to best serve my clients in Passive Solar Architecture, but clearly – much work remains and AGW will at best remain a hypothesis for a long time, at least.

I seriously question all of the “weather” data collected… it would seem that we need to develop a sealed package with built in wireless telemetry to report to an independant 3rd party as well as giss… Dr. Hansen requires observation.

I appreciate all of your work…

It is easy to speculate that the improper orientation of the screen could have caused by some past maintenance activity that resulted in a worker that removed and inproperly replaced the weather station as part of some roof top work. One has to wonder how many times this sort of thing has happened.

I’m going to try my hand at doing a blog (http://dmchatham.wordpress.com/). I’m starting with some of the more obvious arguments using the Vostok ice-core charts.

I bought one of the data-loggers advertised on your site and have used it to compare the difference between Maximum/Minimum (MMTS) temperatures with an average of five-minute readings. I’ll include the results and raw data as I develop enough data to be meaningful. So far, one month’s data shows that the daily average of the maximum and minimum temperatures is ~2 deg. F higher than the daily average of the five-minute readings (ranging from -0.7 to ~4.5, with only one below 0)

25 years writing about the weather? And you haven’t seen it all yet, it appears!

The most important thing to point out to the NWS is that the Stevenson Screen door is not facing north, as is required by NOAA’s own siting specifications. This is to prevent sunlight from striking the thermometers directly when a reading is being taken, possibly raising the temperature. It only takes a few seconds.

Also please see the 100 foot rule that NOAA recommends for station placement:

http://www.nws.noaa.gov/om/coop/standard.htm

Temperature sensor siting: The sensor should be mounted 5 feet +/- 1 foot above the ground. The ground over which the shelter [radiation] is located should be typical of the surrounding area. A level, open clearing is desirable so the thermometers are freely ventilated by air flow. Do not install the sensor on a steep slope or in a sheltered hollow unless it is typical of the area or unless data from that type of site are desired. When possible, the shelter should be no closer than four times the height of any obstruction (tree, fence, building, etc.). The sensor should be at least 100 feet from any paved or concrete surface.

So far, based on our surveys of over 500 stations, proper station siting has been the exception, rather than the rule, nationwide:

http://www.surfacestations.org/images/CRN-USMAP-534.png
and
http://www.surfacestations.org/images/CRN-Rating-534.png

See more stations at http://www.surfacestations.org

Thanks for your consideration – Anthony Watts

Anthony and I swapped emails not long after my story came out. He said that it might be possible that the weather station at Santa Ana Fire Station might not be taking accurate readings. Anthony emailed me an image that didn’t really show the guts of the station. So I had little to follow up on. However, I did call the NWS in San Diego and asked if they’d had any numbers issue with the Santa Ana Fire Station data. I was told that they had not.

But …

Anthony posted more photos and pressed the issue. So I called Ivory Small, the chief science officer at NWS-San Diego. Ivory — who lives in OC — said that forecaster Noel Isla had examined Anthony’s concerns and decided that the weather station was fine. But it’s worth one more look. So I emailed Anthony’s web pages to Noel Isla and asked him to explain how he concluded that the station is operating correctly. Noel’s next work shift doesn’t begin until Saturday afternoon. So I don’t expect to get a response until Saturday or Sunday. But we are looking into the matter.

I’ve got to say, I’m totally impressed by Anthony’s persistence in getting images by having a firefighter go up on the roof with a camera. I like Anthony’s website, too, and I’ll be referring to it off my own blog (ocregister.com/sciencedude).

I’ve been writing about the weather for 25 years. It’s a touchy business. Readers are quick to point out information that they believe is in error. When we’re wrong, we admit it. Most recently, we ran an update from Bill Patzert at JPL, who admitted that he’d overstated the impact of climate change on the average high temperature in Santa Ana. But we hold fast when we think we’re right. I’ve been getting roughed up by readers by reporting that the average high temperature has been higher than normal for the past six months. Many readers have said that the last three months in particular — summer, in other words — was cooler than normal. But the weather readings taken at John Wayne Airport and Fullerton Airport say otherwise.

Either way, this is all fascinating stuff. And I wanted to tip my hat to Anthony for his persistence and for his wonderful blog.

Gary

EUREKA!

G

Amen. Based upon my electronics experience, I would like to add: Including a regular calibration schedule for all stations against a Federal standard.

At GTE we had to send our resistance and capacitance standards out every year to a lab to have them checked against Federal standards, and we were not doing anything as important as this (determining the future lifestyles of the world).

Current temperature readings:
Instruments 90.1 (wireless), 89.2 (wired sensor)

Grass in sun: 91.5 F
Grass in shade: 76.5

Bark in sun: 132.5
Bark in shade: 85.0

Sidewalk in sun: 119.5

Driveway in sun: 121.0
Driveway in shade: 87.0

Light brown wall near instrument shelter in shade: 90.5
Light brown wall near shelter in sun: 124.5
Dark brown wall near shelter in sun: 139.0

Concrete near shelter in sun: 116.0
Concrete near shelter in shade: 86.0

Gardening soil in sun: 113.0
Gardening soil under plants: 83.5

Road surface in sun: 132.5

REPLY: at 12:45 Mather AFB in Sacramento reports 88F, A weather Underground Station in South Natomas reports 91F and Arden Arcade at 91F

-Anthony