Mike Crimmins, Extension Specialist - Climate Science, University of Arizona
Tracking patterns of drought is a tough job across the semi-arid, Southwestern U.S. Complex topography drives steep gradients in precipitation patterns over short distances. Further, monsoon thunderstorms can drop flooding rains in one location while nearby areas remain dry, sometimes for the entire summer season. This variability is not abstract to ranchers and land managers who see these patterns expressed in varying levels of forage production and range condition across the vast grazing lands of Arizona and New Mexico. Precipitation observations become important data points to help make management decisions within the grazing season and to assess the role of climate in longer-term changes observed in range monitoring data.
These precipitation observations don’t come easy, and often aren’t readily available through official monitoring networks run by the National Oceanic and Atmospheric Administration (e.g. Cooperative Observer data). Official monitoring networks are located where people live and work and where observations can be taken frequently. Rangeland areas are often far away from these official networks, so if precipitation observations are needed, producers and managers have to set up their own rain gauges. These gauges are often simple PVC tubes, capped at one end and filled with an oil evaporation barrier that can be read once a year when monitoring is done ,a clever approach that helps provide a key data point when interpreting range monitoring data over time.
Simple PVC gauges work well and are used widely across Arizona and New Mexico. However, in our work with ranchers and land managers, we have found that there is interest in exploring new ways to make the collection of precipitation observations easier and more frequent as well as to develop tools to help manage and interpret these observations. This led to the development of a new rain gauge design and an online tool called myRAINge Log. MyRAINge Log is a web-based data management and visualization tool designed specifically for cumulative precipitation observations at remote sites -- the type of monitoring done in rangeland management. A key feature of myRAINge Log is the ability to plot observations against a historical climatology of precipitation estimates for that location drawn from a gridded precipitation product (PRISM). This provides context for interpreting rain gauge observations with short records and can help highlight how an observation compares to the historical climatology.
MyRAINge Log was co-developed with a group of ranchers and land managers in Arizona. These individuals provided feedback at several points in the design process. Their specifications included that the tool be able to handle numerous gauges within one account, work offline, chart observations with historical data, and generate reports with field notes and photos. All of these features have been implemented in an effort to make precipitation data collection easier and faster to incentivize the collection of more data throughout the year – more data points to help interpret changes on the range. Registration is free and the site is continuing to undergo updates and enhancements based on user feedback.