Dan Kump

CE547, GIS in Water Resources Engineering

UNM Spring 2008

February 17, 2008

RE: New Mexico Pan Evaporation

The Pan Evaporation Homework Assignment provided training in the use of shape files for the New Mexico Counties and for the pan evaporation stations. One item that Homework Assignment No. 2 (HW#2) allowed me to do is to gain greater familiarity with the locations and names of the New Mexico Counties. I now know that there are 33 counties in New Mexico. Another item that HW#2 allowed me to learn is that there are 25 pan evaporation stations in New Mexico. Given the preceding statements, there are counties in New Mexico that don’t have evaporation stations. Actually, some counties have multiple stations; and some counties don’t have any.

Probably the easiest thing to do for pan evaporation in New Mexico would be to simply take the average of the station data and use that value for New Mexico Pan Evaporation. Keep in mind that the convention for converting pan evaporation to average expected evaporation is to multiply pan evaporation by 0.7. One could develop various schemes to more accurately estimate the evaporation in the various counties.

The third item that I learned doing this homework is to create a graph using the GIS software. The deliverables for this assignment are:

(1) a map of the counties in New Mexico; (2) a graph of the evaporation for an area of New Mexico using three of the stations. I used the Estancia, Los Lunas and Santa Fe pan evaporation stations to make a graph for pan evaporation in Central New Mexico.

Map of New Mexico Counties and Pan Evaporation Stations

Graph of Three Selected Pan Evaporation Stations