March 8, 2017
At the Judith Currys’ blog Climate etc here, a comment here by Geoff Sherrington presents the link to a temperature dataset of 44 (45 for me) stations selected as the available most pristine ones (i.e. as less affected by human activity as possible). Data are available at the support site (DM40) and at Geoff’s site here.
The author of the dataset confirms he filled lost data by eyeballing a suitable mean and that data are not much useful apart the case where a comparison is needed with non-australian data.
I downloaded the dataset and used both my calculations and Geoff’s results (e.g. he gives slopes without errors or doesn’t compute spectra). For sake of clarity I divided all stations (alphabetically ordered) in 7 groups: 6 of them contain 7 stations and the last one the remaining 3.
In fig.1 (pdf) an example of the first group is shown, the other ones beeing available at the support site.
Fig.1. TMAX (top plot) and TMIN temperature for the first 7 stations listed on the right side.
The stations have been linearly fitted and the first 7 fits are in fig.2 (pdf)
Fig.2. Linear fit of the first 7 stations for both TMAX and TMIN. Numerical values are at the support site.
The MEM spectra have been also computed and, again, the first 7 stations
are shown in fig.3 (pdf). Numerical values are at the support site.
Fig.3. MEM spectra of the first 7 stations, both TMAX and TMIN. Spectral shape of top and bottom plots, also for the other groups, appears different.
The slopes of the stations have been set in relation (by Geoff) with Longitude, Latitude, Altitude asl, Distance from Sea and, as (almost) a joke, with WMO code and Ordinal (i.e. alphabetical order) of the stations, for both TMAX and TMIN. Results for TMAX are in fig.4 (pdf) and fig.5 (pdf)
Fig.4. Longitude, Latitude, Altitude asl vs. Slope of all stations.
Fig.5. Distance from Sea, WMO # and Station # vs. Slope of all stations. Numerical values available as max.app and min.app at the support site.
Some connection appears between slope – longitude and slope – altitude.
With surprise, slopes seems to be not related with the distance from sea shore.
The funny plot of slopes vs station ordinal doesn’t give any relation at all, of course. The slope shown a (weak) relation with the WMO code, depending, may be, on the choice of WMO (related to long and lat).
|All plots and numerical data for this article are at the support site here|
January 10, 2016