National rainfall datasets have limited coverage in the Sonoran Desert region of Southwest Arizona. Due to the large geographical area which needs to be covered, and the limited rain gauge locations, it can be impractical to use the national precipitation dataset estimations on a local scale. The Arizona Cooperative Rangeland Monitoring Program (ACRMP) has placed rain gauges at all of its vegetation monitoring key areas in La Paz County, Arizona, in an effort to better understand the local annual rainfall patterns in grazing allotments that are underserved by the national datasets. Spatial interpolation is a useful tool for estimating rainfall patterns in areas between rain gauges. Through the use of the ArcGIS inverse distance weighted (IDW) interpolation tool, it is possible to calculate a simple gradient of rainfall over a large area which could not be feasibly measured otherwise. The local rain gauge IDW interpolation is compared with the national precipitation estimates to further refine the accuracy. The resulting geostatistical model can help land managers and land users working with the ACRMP to visually understand local climate irregularities so they can make more informed decisions.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.