Climate change induced changes in moisture availability in eastern Wyoming ranchlands with management recommendations for adaptation

Abstract

In the future there is an expectation for climate change to have impacts on both natural systems and agricultural enterprises. A number of studies have been conducted for the purpose of determining the effects of a changing climate on agricultural enterprises, but most of these studies are large scale in their scope and give non-specific recommendations for adaptation. In the United States much of agriculture, including ranching, requires large capital shifts to change their products and as such they need to have more specific advice as to how to respond. Having more specific advice today also means that individuals in agriculture can start planning to adapt today, rather than being surprised a few decades from now. This project utilizes historical climate information and projections of future temperature and precipitation based on IPCC regional expectations and local climate variability. These projected values were used in two versions of the Thornwaite moisture balance model to calculate a range of possible changes for moisture availability from 2009 to the year 2100. The estimated changes in available moisture (potential evapotranspiration, soil moisture, atmospheric moisture deficit, etc.) were compared to the baseline values to determine the decrease from normal values. The literature was searched to determine the amount of decrease in moisture availability that would likely result in ecological drought and hinder production. The evidence indicates that there will be varying degrees of diminishing of available moisture dependent upon the amount of temperature increase. Because of the range of possible impacts, a variety of management practice recommendations are included, as well as mechanisms to monitor the climate more carefully to better spot droughts as they begin. For scenarios with severe shifts in the climate, recommendations are made to make strong changes in their production methods or the uses of the land.