Arkansas - the homogenized data results

Unfortunately I still do not have access to the CDIAC server showing the information on the USHCN sites in Arkansas, so as I discussed last time I have obtained the information from the surface stations site and then downloaded the various station temperatures from the GISS site. Unfortunately this does not include the TOBS data, only that homogenized before being published. There are some problems with that homogenization, which really requires both sets of data to illustrate, but I’ll leave that for now, just to do an initial review of the Arkansas initial data set, and to look at the population data.

There are only 15 USHCN stations, and one GISS station (Fort Smith) on the list, so that the initial work was not that demanding.

Fort Smith GISS temperatures

The difference between the GISS station and the average of the USHCN curves uses the same data set as in the rest of the series:

Difference between the GISS temperature and the average of the homogenized station data for the USHCN stations in Arkansas

The shape of the curve seems to show an increasing difference through about 1948, and then a decline since that time. Given the switch in some series to only using data after 1948 this is slightly curious.

Turning to the overall change in temperature of the state over the century, and now using the homogenized data (hence the purple) rather than the TOBS raw data, the line still does not show very much of an increase over the past century.

Average temperature change in Arkansas over the past 115 years.

The temperature has been increasing at the rate of some 0.05 deg F per century, which is not a lot.

Arkansas is some 260 miles by 240 miles in size running from roughly 89.6 deg to 94.7 deg W in Longitude, and 33 deg to 36.5 deg N in Latitude. The highest point is at 839 m, and the lowest is at 16.7 m, with the average elevation of the state being at 198 m. The average USHCN station is at 176 m, and the GISS station is at 134 m.

Checking the populations, that of Rohwer is too small for citi-data, so I used zip area code to find 77. Fort Smith (the site of the GISS station) has the largest population of the stations.

Looking at the effects of the geography on the temperatures, beginning with the effect of Latitude.

Effect of latitude on temperature in Arkansas

There is the usual strong correlation, whereas with Longitude:

Effect of longitude on temperature in Arkansas

As has been discussed before, any correlation is likely an artifact reflecting changes in elevation.

Effect of elevation on station temperature in Arkansas

When one looks at the effect of population, using the homogenized data, rather than the TOBS data, then there is sensibly no effect of population, in fact such correlation as exists is negative.

Effect of population on temperature in Arkansas after the data has been homogenized.

Arkansas unavailable - hopefully just a short break on the temperature study

How long should a government run website be down? I ask because I was getting ready to download the data for the continuing study of state temperatures on Friday, intending to download the statistics from the USHCN network for Arkansas, and then compile the data, plot the curves, and write the post today. Unfortunately when I went to the site through which I go to get to where the data is:

http://cdiac.ornl.gov/epubs/ndp/ushcn/ushcn_map_interface.html

my laptop got a notice that:


Well without the data, it is hard to do any analysis. I presumed that it was a transient glitch, and went off to do other things. Came back this evening (after driving through the driving snow to Dartmouth College at noon) and got the same message, about a day later. So I went back to the NASA main website for climate change at GISS, and clicked on the:

http://cdiac.esd.ornl.gov/epubs/ndp/ushcn/newushcn.html

pointer and got the same message. (Which is also where the NOAA folk tell you to go and look).


The long way around would be to download the names of the Arkansas state stations from the Surface Stations website and then go to the GISS site, and download the data from there. Unfortunately that would only provide the homogenized data for the stations (as I found in an earlier state) not the TOBS data, which correlates better with the geographical information and population.

So I will presume that this is just a temporary problem at the site, and that, after the Easter Weekend is over, perhaps the server will be put back on line, and I can get back in business.

For now, Happy Easter, and my apologies.

Oh, a small update, I (out of curiosity) entered one of the file data references that I have used before to see if I could get around the problem that way, and got the information that:

Safari can't find the server "cdiac.csd.ornl.gov

Which was where it came from - wonder what's going on??