Examining Soil and Drought Dynamics to Improve Fire Forecasting in the southern Great Plains 2002-2011

Precipitation amounts, and frequencies are major regulators of soil heat-load profiles as the interval between rainfall events allows for increased heat storage during cloudless days. The extreme drought of 2011 and the subsequent Flash Drought that occurred in summer, 2012, developed in part due to soil temperature dynamics across the landscape of the Southern High Plains. For both agroecosystems and natural landscapes within the South-Central Region, soil temperature has a major role in determining the success of annual cropping systems, the ability of perennial plants to either establish or maintain themselves and the ability of the soil bacteria and fungi to carry out important decomposition and nutrient cycling, which are crucial for ecosystem services. Not only does soil temperature dynamics influence plant growth and contribute to drought development, soil temperatures levels and the amount of variability in soil temperatures across a 24 hr period can also have a role in creating and promoting conditions that increase the capabilities of dried vegetation to maintain a fire. This project utilized the soil temperature data collected by the West Texas Mesonet (WTM) system for the period 2000 to 2014 to evaluate landscape level soil temperature dynamics across the Southern High Plains. For our analyses, we used thirty-three WTM locations that had continuous data from 2000 to 2014. We used several analytical approaches to look at how seasonal and yearly weather patterns influences soil temperatures and temperature variability across the landscape. From the Mesonet data we were able to generate three types of graphic representations of the soil temperature dynamics: 1) soil temperature profiles for a wet year (2004), an average year (2006) and a dry year (2011), three-dimensional representation soil temperature profiles from 12:00 AM through 11:59PM for the period 2000-2014 and daily temperature profiles for the period 2000-2014. Based upon these analyses two major determinants of soil temperature dynamics across the region were observed: 1) rainfall amounts and frequency was a major determinant of soil temperature patterns and amount of daily temperature variability observed, and 2) the responses of soils to precipitation/temperature interactions and subsequent seasonal patterns is highly dependent on soil type (amount of sand, silt and clay). Based upon these analyses how the landscape enters and subsequently responds to drought and contributes to drought is very location specific and is dependent upon soil type and vegetation cover. Moreover, how soils store heat and differ in their seasonal temperature dynamics at various locations on the SHP in response to yearly differences in weather contribute to the high variability in fire weather outcomes.

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  "010:00"
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  "geospatial"
]