EFFECTS OF EL NIÑO/SOUTHERN OSCILLATION ON HYDROLOGICAL CONDITIONS IN NORTH CAROLINA

El Niño/Southern Oscillation (ENSO) is the periodic shift in ocean and atmospheric circulation in the central and eastern Pacific that also has implications for global weather patterns. The effects of ENSO on climate and hydrologic variability have been documented in the southwestern USA and other regions bordering the Pacific Basin. However, few studies have quantified the effects of ENSO on the climate and hydrology of the southeastern US. Given recent concern over drought conditions across this region, more research is needed to understand the effects of ENSO on seasonal and interannual precipitation and water resource availability in the southeast.

We compiled up to 56 years of precipitation and streamflow data from monitoring stations across North Carolina and surrounding states. We compared seasonal trends in these data to the Multivariate ENSO Index (MEI). Correlation analysis indicates that ENSO conditions influence precipitation significantly in North Carolina, and that the magnitude of this influence is greatest along the southern Atlantic coast and decreases with distance inland. We applied similar statistical analyses to streamflow data to determine whether hydrological variables exhibit a similar response to ENSO. These results have implications for understanding interannual fluctuations in hydrological variables in the southeastern US.