Tag Archives: ushcn

USHCN V2 Deletions and Additions

Menne et al (J Clim 2009) reported that there were 62 station deletions and 59 station additions from the most recent roster (which itself had been modified from the original USHCN in the mid-1980s. Menne et al: Since the 1996 release (Easterling et al. 1996), numerous station closures and relocations again necessitated a revision of […]

What a great USHCN station looks like: Tucumcari

I’ve spent a lot of time on this blog showing how badly maintained and situated the stations in the USHCN network are. And rightly so, the majority of them have issues. But, finding the good ones is actually more important, because they are the ones that hold the true unpolluted temperature signal. Unfortunately, the “good […]

A Second Look at USHCN Classification

Yesterday, I posted up a first look at differences between station histories classified as CRN=1 (good) versus CRN=5 (bad) – a simple comparison of averages, noting that other factors may well enter into the comparison. A couple of other points that I’ve made consistently as we look at these results which I’d like people to […]

First Look at the USHCN Quality Classification

Anthony Watts has posted up a quality assessment of the USHCN stations here. John V presented some graphics in the comments thread here and below is my first pass – this comment is not intended to exhaust all possible cross-cuts of the data is merely the first thing that I looked at. I compared the […]

Tom Karl’s Station Adjustments

The USHCN Station History Adjustment procedure is credited to Tom Karl in Karl and Williams 1987. Karl has been very prominent in the IPCC movement. That’s not to say that the potential adjustment is wrong or unjustified, but that the adjustment needs to be scrutinized with the same care as one would scrutinize an adjustment […]

Adjusting USHCN History

Although the USHCN version used in Hansen’s 1999 press release seems to be expunged from official U.S. government records, it was fortunately preserved by John Daly. Jerry Brennan sent me a link to a version preserved by John Daly yesterday, from which I was able to replicate the version in the 1999 press release, as […]

The 1930s are getting Colder

According to the National Climatic Data Center (NCDC),, covered here, a new Beta version of the U.S. Historical Climatology Network will be released next year. They say that the new data set uses “recent scientific advances that better address uncertainties in the instrumental record. Because different algorithms were used in making adjustments to the station […]