This function calculates the spatial correlation between two variables over an X-Y domain. It returns a single number. The syntax is:

`scorr(`*expr1, expr2, xdim1, xdim2, ydim1, ydim2*)

where:

*expr1*

- any valid GrADS expression *expr2*

- any valid GrADS expression *xdim1*

- starting X dimension expression *xdim2*

- ending X dimension expression *ydim1*

- starting Y dimension expression *ydim2*

- ending Y dimension expression For global averaging, a shorthand may be used:

`scorr(`*expr1, expr2*, global)

or`scorr(`*expr1, expr2*, g)

`scorr(`*expr1, expr2*, lon=0, lon=360, lat=-90, lat=90)

`scorr`

may be used in conjunction with`tloop`

or`define`

to create time series or time/height plots.`scorr`

assumes that the world coordinates are longitude in the X dimension and latitude in the Y dimension, and does weighting in the latitude dimension by the delta of the sin of the latitudes. Weighting is also performed appropriately for unequally spaced grids.

This example calculates the correlation between the surface temperature and the latent heat flux over the tropical Pacific:

set lat -10 10 set lon 120 280 d scorr(tsfc, lhtfl, lon=120, lon=280, lat=-10, lat=10)