The attached archive contains long term mean precipitation values in autumn (September, October, November) and in spring (March, April, May) measured in the Baltic meteorological stations.

1. Calculate spatial correlogram between these variables at 10 km wide distance intervals up to 500 km. Add the correlogram to the answer.
2. At which interval is the spatial correlation between spring and autumn precipitation amount statistically significant at p < 0.01 level?
3. How to interpret this correlation climatologically?

The online calculator of spatial data offers tools to solve also this exercise.
Find Spatial correlation, set paremeters, press calculate and analyze the results. Correlation is significant if the quotient value is outside the envelope calculated from randomly permutated data.