Exceedance Probability of the Standardized Precipitation-Evapotranspiration Index in the Texas High Plains

Abstract

Drought is a common occurrence in many arid and semi-arid regions that can have large negative impacts on water resources and agricultural production. Since agricultural drought is affected by both water supply and demand (precipitation and evapotranspiration), it is beneficial to include both in agricultural drought monitoring. The Standardized Precipitation-Evapotranspiration Index (SPEI) was found to be a suitable drought index for monitoring agricultural drought. In this study, the SPEI calculated from agro-meteorological weather stations was used to determine exceedance probabilities at five levels in the Texas High Plains. In addition, the kriging method was used to interpolate between the stations to generate spatial maps for the exceedance probabilities. No significant differences were found between stations, indicating any station should be suitable to represent the Texas High Plains. Results showed drought conditions occurred at all five probability levels during the summer growing season for this region. Although differences were not significantly different, the interpolated maps showed a trend where minor differences in the SPEI values were associated with the West-East precipitation gradient. However, there was no trend associated with the North-South air temperature gradient. A risk analysis showed that the SPEI probability values can provide policy and decision makers with additional information for better water management in the Texas High Plains.

Global Sensitivity Analysis of the Standardized Precipitation Evapotranspiration Index at Different Time Scales in Jilin Province, China

“…Numerous studies have demonstrated that the SPEI is both multi-scale and comprehensive. In particular, in the context of global warming, considering T mean , T delta , RH, Rs, U 2 , G, and P, the SPEI is able to effectively identify different drought types [7,[9][10][11]. However, the effects of T mean , T delta , RH, Rs, U 2 , G, and P on the SPEI still remain unclear, especially at different time scales.…”

“…In particular, the SPEI, put forward by Vicente-Serrano et al (2010), is not only highly sensitive to changes in evaporation, but is also characterized by a simple calculation and its ability to consider multiple time scales. Due to a broad range of meteorological variables in the context of global warming, the SPEI is able to comprehensively identify different drought types [7,[9][10][11][12]. Thus, the SPEI has proved to be highly effective in the detection, monitoring, and exploration of drought [7].…”

Assessment of Landsat-Based Evapotranspiration Using Weighing Lysimeters in the Texas High Plains

“…Bushland Evapotranspiration and Agricultural Remote Sensing (BEARS) is an image processing and geographic information system (GIS) software developed by researchers at the USDA ARS CPRL in Bushland, TX, used for deriving hourly, daily, and seasonal ET maps, and other energy exchanges between land and atmosphere using Landsat 5,7, and 8 [42]. It is an open-source Java software, Version 1.0.1 available for download at: https://data.nal.usda.gov/dataset/bushlandevapotranspiration-and-agricultural-remote-sensing-system-bears-software.…”

Spatial and Temporal Characteristics of Drought and Flood in Quanzhou Based on Standardized Precipitation Index (SPI) in Recent 55 Years

“…The SPI index based on precipitation data not only has the advantages of simple calculation and multiple time scales, but also can compare droughts and floods in different spaces and has good stability. In extreme cases, it is superior to the widely used Z index in the country and has been widely used in drought monitoring [2] [3] [4] [5]. Livada and Assimakopoulos [6] used the rainfall data from the Greek meteorological station to calculate the SPI values in Greece and analyzed the temporal and spatial changes of the drought in the region.…”