This is a next stage in the display of Earth data with WebGL. It uses the general framework described here. BEST and GISS are temperature anomaly datasets, available on a 2° by 2° grid. In fact, BEST has 1° resolution, but I amalgamated cells to match GISS, mainly to alleviate download time. GISS uses ERSST ocean data.
For each cell, an OLS trend coefficient over time (°C/century) is calculated and shown with color shading. You can choose start and end years, from 1889 to 2013. Press "Plot New" when you have made a choice. The Earth is a trackball, as in Google Earth. You can press "Orient" to get it right way up.
When you click on any point, the location and trend are shown on the right.
BEST describe their methodology in various papers, access from here. GISS methods are described here, with links.
Update. I've implemented Carrick's suggestions - see below plot for details.
UpdateFollowing Carrick's suggestions I have provided a new set of inputs, blue box on right. The simplest is "Level"; you can enter a level (eg 0) that you want to show in white. It isn't complete for contouring because in some gradients that level will be skipped. But it gives a guide.
The top window is marked mean,sd. The color scheme is set by two parameters, mean and sd of data. These are shown below the text box. If you enter two corresponding numbers in the text box, that will override. Two ways you might use this:
- You can force two plots to have matching color levels. Just copy the numbers from one into the text box of the other.
- If you really want to emphasise the transition through a certain level, choose that as the mean, and put in a fairly small sd. The result will be mainly red and blue, but showing the transition region (eg 0) in colors.