## Category Archives: NASA (Hansen)

### Homogeneity Adjustment – Part II

Yesterday I described the work done to the surface station records in Hansen Step 2 in preparation for adjusting urban stations to match the trend of nearby rural stations. The basic substeps are Deciding which stations are rural and which are urban. The methodology used for most of North America differs from that applied to […]

### Homogeneity Adjustment – Part I

My curiosity in the mathematics behind the homogeneity adjustment caused me to finally take a close look at Hansen Step 2. This turned out to be an incredibly torturous task. A quote from a Stephen King short story, The Jaunt, came to mind as I plowed through lines of code: “It’s eternity in there…“. However, […]

### Rewriting History, Time and Time Again

Update: As noted in the comments below, GISS updated the GLB.Ts+dSST anomalies which show a large 0.67 degC value for March. This addition of March 2008 temperature data to the record caused a corresponding drop in annual average temperature for the years 1946 and 1903. According to GISS, 1946 is now colder than 1960 and […]

### Hansen and "False Local Adjustments"

Over the last few days, I’ve shown that Hansen et al 1999 illustrated and discussed the effect of the NASA adjustment for two stations (Phoenix, Tokyo) where the NASA urban adjustment yielded the expected adjustment (denoted in these posts as a “positive” adjustment). In an earlier post, I’d observed that negative urban adjustments (i.e. for […]

### Positive and Negative Urban Adjustments

A few days ago, I commented on the surprisingly large negative urban adjustments made by NASA at several Peruvian stations. I’ve now calculated the maximum negative and maximum positive urban adjustments at all NASA stations – something that I was able to do only because of my scraping of NASA data from their website (something […]

### Phoenix and Tokyo: "Traditional" UHI

In my discussion of Peruvian stations, I noted several examples of negative urban adjustments. A couple of readers inquired as to whether there were any examples of the opposite effect. In fact, Hansen et al 1999, the primary reference for the present-day GISS adjustment methodology provides using two such examples (the only ones discussed): Phoenix […]

### Hansen's "Rural" Peru

Hansen’s downward adjustments of Peruvian temperature records by as much as 3 deg C is based on the presumptive quality of Peruvian “rural” sites. If one even spends 40 minutes examining the locations of these sites, any resemblance to rural USHCN sites disappears. In addition, the failure of NOAA and NASA to update their records […]