Proceedings of the 2020 Mississippi Water Resources Conference

Year: 2020 Authors: Ouyang Y., Feng G., Moran M.

Climate change is a natural phenomenon, but anthropogenic activities such as fossil fuel burning, industrial pollution, deforestation, and population growth have greatly accelerated the greenhouse gaseous emissions and have resulted in abnormal climate change patterns. Climate change over the last several decades has been linked to atmospheric water vapor content increase, precipitation pattern shifts, snow cover reduction and ice melt, and surficial hydrological process cycle changes. Lower Mississippi River Alluvial Valley (LMRAV) is an economic artery of Mid-south USA, which is prone to natural disasters from extreme climate events and is well known for cyclic flooding events, groundwater level decline, and surface water quality degradation. Currently, our knowledge on long-term precipitation trends in this region is fragmented. Using the past 100 years measured daily precipitation data from six watersheds within the LMRAV in conjunction with nonparametric analyses (i.e., Kruskal-Wallis, Dunn, Mann-Kendall, and Pettitt tests), we found that there were significant increasing trends (p < 0.05) in annual precipitations near the coastal area. A spatial variation in seasonality was also observed at the decadal scale. Results from this study are useful to water resource managers for adapting the changing climate conditions in the LMRAV.