Date of Award

6-2025

Degree Name

Master of Science in Accountancy

Department

Geography

First Advisor

Lisa DeChano-Cook, Ph.D.

Second Advisor

Rudy Bartels, Ph.D.

Third Advisor

Lei Meng, Ph.D.

Keywords

Atmospheric rivers, California, drought, flood, Pacific Decadal Oscillation, standardized precipitation index

Access Setting

Masters Thesis-Open Access

Abstract

This research is investigating the climate states that produce droughts and floods and seeks to explain how a sudden shift from persistent drought to drought-alleviating flood is possible. Objectives include investigating how drought and flood in California are influenced by temperature and climate patterns, whether there are any correlation between climate/ocean indices and the Standardized Precipitation Index (SPI), and whether Atmospheric Rivers (ARS) are influenced by certain atmospheric/oceanic states.

All data is collected for 41 years, between 1983 and 2024. The SPI dataset is obtained by coding to filter for the mean value of all pixels in Sacramento County. Monthly temperature data are downloaded from the PRISM Climate Group, and monthly climate indices data are downloaded from the National Oceanic and Atmospheric Administration (NOAA). Pearson’s R is run to test the correlation between SPI values and temperature for rainy and dry seasons. Four sets of Sliding Window Correlation (SWC) tests are run to analyze the correlation between droughts and floods, based on anomalous wet and dry years derived from SPI calculations, and six climate/ocean indices.

Direct relationships are observed between the Pacific Decadal Oscillation (PDO) and both drought and flood events. PDO has the strongest correlation results with SPI compared to the other indices and may influence shifts from drought to flood. SPI values do not always align with real-world experiences of dryness and wetness. ARs and climate patterns, including PDO, can influence each other.

Download

Share

COinS