Spatial and Temporal Assessment of Meteorological Drought Using the Standardized Precipitation Index (SPI) and Its Effect on Crop Yield Over the Corn Belt Region of the United States from 2000 to 2023

Abstract

Climate change and global warming have contributed to extreme weather events and patterns, including severe flooding, earthquakes, wildfires, and drought. Drought happens to be the deadliest catastrophic event around the world. Drought's impact on ecosystems and local communities has been increasing in many parts of the world, including the United States and, most importantly, the Corn Belt, which also happens to be the country's food basket. Drought prediction and mitigation can be investigated through drought indices. The standardized precipitation index (SPI) is considered the most reliable in this study. The index is the most reliable as it serves as one of the most fundamental.  It is used in this study to present the critical identifier for diagnosing the intensity, duration, and frequency of drought severity. Additionally, SPI is a key identifier in extreme precipitation events. It is comparable to various landscapes across a region and is simple to use concerning its calculation process. This study focuses on the Midwest Corn Belt Region of the United States, between the climate record from 2000–2023. This study is designed to understand precipitation regimes and their impact on cropland cover and yield (condition monitoring and crop progress) over the climate record. Results of the study showed drought affecting portions of the region, especially during the first half of the period, with 2012 indicating peak severity plaguing both corn belts. Generally, pre-2012 and post-2012 indicated the wettest conditions, especially in 2010, 2014, and 2016. While cropland cover highlighted the widespread distribution of corn and soybean cover in both Corn Belts, crop condition and progress corresponded and responded well to low yields during the intense drought years and high yields during the wettest years. Our analysis shows that climate change has undoubtedly resulted in a temperature rise, exacerbating the frequency and severity of heat waves and extreme precipitation events impacting parts of the United States, including the Corn Belt.