Posted by Jason Polak on 30. June 2013 · Write a comment · Categories: statistics · Tags: , ,

The internet has enabled researchers and organisations of various kinds to make their data available for free to download and hence anyone with a computer and some rudimentary R knowledge can observe and analyse all sorts of trends in everything from economics to society to natural phenomena. Obviously this can provide endless hours of fun and distraction!

One such data set, available at Willmott, Matsuura, and Collaborators’ Global Climate Resource Page is a dataset that was compiled by Legates and Willmott and described in their paper [1].

This dataset is a set of estimated mean monthly surface air temperature values for various (points on a 0.5 by 0.5 degree grid) geographical locations and was made from 17986 land weather stations (most densely concentrated in the United States and Europe) and 6955 ocean recorded points. These observations came from various sources and span a period of sixty years, and were used to estimate and interpolate the temperature at various points. To give you an idea of how much data was collected, here is a map from their paper [1] showing the location of the stations (I figure showing this map is fair use):


The details of the estimations are documented in the paper, and estimated errors are also available on the website above. Although there are some pictures in the paper, they are in black and white and I thought it would be fun to make some in colour.
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