Cloud Fields

The cloud amount data is consists of 20 hourly fields of cloud amount on a 55X26 grid at a resolution of .7° x .7°. The latitude ranges from -10° to 10° and the longitude ranges from 135° to 175°.

The 20 images start on Feb 1, 1993 and are every 6 hours. Thus there are 4 snapshots per day for 5 days (from the first hour on Feb 1,1993 to the 18th hour on Feb 5, 1993). postscript image plots of the data

The file has cloud amounts in one long listing with the subscripts in order latitude (1-26), longitude (1-55), time (1-20) from fastest to the slowest varying. Cloud amount compressed data file (138K) To unzip this file in UNIX:


The following S code reads in the data from the text file and reformats as a 3 dimensional array. The rest of the S code plots the 20 fields in sequence. The ordering of the subscripts is reversed to make the image plots come out right. The first subscript is over latitude and the second is over longitude. Use the aperm function in S if you want to reverse these.

# reading the data into R,S

scan( "")-> out
array( out,c(26,55,20))-> out

#Plot of 20 cloud images (see above)

for(k in 1:20) {
image(out[,,k], xaxt ="n", yaxt= "n", xlab = "", ylab = "", zlim = c(0, 1))
title(paste( "time=", k))