The Effects of Local Weather Patterns on Nitrate and Sulfate Rainwater Concentrations in Wilmington, North Carolina

Abstract

Analysis of weather patterns on a synoptic or regional scale is the common direction of study in air pollution meteorology with few studies analyzing weather conditions proximal to collection sites. A study that focuses on local weather conditions may lead to better understanding and more accurate forecasting of rain water chemistry than synoptic or regional scale studies. The objective of this project is to determine the relationship between local weather patterns and rain water chemistry in Wilmington, NC. Daily and hourly meteorological data (average temperature, relative humidity, wind speed and direction, and maximum and minimum temperatures) were collected for the 48 hour period prior to each rain event. In addition, the nitrate and sulfate concentrations were obtained from the Marine and Atmospheric Chemistry Research Laboratory (MACRL) at UNCW. Data analysis of local weather conditions 48 hours prior to 24 storm events, including review of descriptive statistics, graphical and linear regression analysis, t-tests, and synoptic weather map analysis, was completed to determine any relationship between variables. The overall conclusion of the study is that there are no obvious or significant relationships between nitrate and sulfate concentrations and local meteorological variables. However, wind direction frequency and statistical tests suggest that trajectory, whether terrestrial or marine, is the most important factor influencing rain water chemistry.