Thomas Swetnam of the tree ring research laboratory (Univ. Ariz)
has compared fire size and number to hydrology. For example, in
"Fire Effects in Southwestern Forests, proceedings of the Second
La Mesa Fire Symposium," (USFS, Rocky Mtn Forest and Range
Experiment Station, 1996) he created a graph that compares fire
size /frequency to the Palmer drought severity index for the period
from 1700 to 1980 for the southwestern U.S.. The two are -- as you
would intuitively expect -- quite well correlated, with the more /
bigger fires occurring in the dry years, fewer smaller fires in the wet
years.
John
See http://basin.org/forum/fire-flood.html for more information on this list.