33% of the USHCN network has been surveyed

10 09 2007

I’m pleased to announce that 33% of the USHCN network of 1221 weather stations has been surveyed now by www.surfacestations.org volunteers. With 404 stations surveyed so far, 817 to go. The Midwest is filling in, and distribution of surveyed stations is more balanced than before. See the map below to see the distribution:

I’d like to give special recognition to five volunteers; Bob Thompson, Eric Gamberg, Russ Steele, David Smith, and Don Kostuch, whom turned summer travels into survey expeditions. Don Kostuch has surveyed more stations, and covered a broader geographic area than any other surveyor. Thanks to all who have helped make this possible.

Trends related to station siting and station equipment that started emerging in the early stages of the survey have held through 20%, 25%, 30% and now 33%. Given that, I feel confident enough to release some preliminary tallies which illustrate those trends and to keep a running trend tally on the website.

The tabulation method and output is currently under review for any errors, and I expect to be able to release it in the next 2-3 days. Once released, it will remain on the www.surfacestations.org website and will be updated regularly.

Now for those whom will likely say that “the USA only has 2% of the worlds area, so it really doesn’t matter”, I’d point out this graphic from NCDC which shows the distribution of weather stations that have mean temperature records going back to 1900. The USA makes up the lions share of the weather stations in the world with complete data sets spanning 100 years.

GHCN mean temperature data back to 1900
GHCN stations with mean temperature data from present to the year 1900.

The USA data clearly makes up the bulk of the last century’s worth of mean temperature data. And there are few candidates that span 100 years in many continents. More detail described in this NCDC report:

www1.ncdc.noaa.gov/pub/data/documentlibrary/tddoc/td9100.pdf

One of the most true and revealing statements in that NCDC report on the worldwide GHCN data is this:

“Because most instrumental networks were established to monitor local weather and not the long-term climate, there are practical problems in using these data to study climate change.”

In the next couple of days, I’ll be highlighting some of the new “practical problems” that have been discovered in the USHCN network in the United States.