T44 A Showcase of Undergraduate Research in Hydrogeology (Posters)

Sunday, 22 September 2024
8:00 AM - 5:30 PM
Hall D

AN ANALYSIS OF NOAA MONTHLY AND DAILY PRECIPITATION DATA TO IDENTIFY LONG-TERM TRENDS SINCE 1900 IN THE TENNESSEE RIVER BASIN

Paper number: T44-12
Program: Technical Sessions
Time: 8:00 AM – 5:30 PM

Authors

  • Theo Kline Presenting Author
    Tennessee Tech University, Cookeville, TN
  • Evan Hart
    Tennessee Tech University, Cookeville, TN

Abstract

Precipitation patterns across the Tennessee River basin are dependent on many factors including elevation, proximity to the Gulf of Mexico, and the occurrence of mid-latitude frontal systems. Much of the state is rural and climate trends remain understudied as a result. Control structures in the Tennessee basin provide flood mitigation for the basin and downstream areas (i.e., the Mississippi River). The aim of this project is to investigate long-term trends in precipitation within the Tennessee River basin using version 4 of the National Oceanic and Atmospheric Administration’s (NOAA) Global Climate Historical Network monthly data (www.ncei.noaa.gov). This dataset includes a file for each station containing the station ID, location, elevation, 4 digit year and 2 digit month, precipitation value (tenths of mm) and other index data.

We chose stations within the Tennessee River basin defined by latitude 37°34’ - 34°04’ N and longitude 90°18’ - 81°12’ W. Stations that did not meet 100 years of data were removed from the dataset. In addition, seven stations were excluded due to large data gaps, leaving 121 stations that met these specifications.

We utilized the Mann-Kendall statistical test to detect increasing or decreasing trends in precipitation data. To apply this over the course of one year, each station’s records were first processed in a program to separate each year into 12 months. The Mann-Kendall test was then processed in an auxiliary program for the monthly datasets.

Results from the analysis show that monthly average precipitation trends (p < 0.05) increased at a greater frequency than they decreased. However, most stations showed no trend in monthly average precipitation. The months with the highest percentage of stations showing increasing trends were May (36%), October (28%), and November (27%). Decreasing trends were found for stations during the months of July (8%), February (3%), and August (2%). The majority of stations showed no significant trends whatsoever, ranging from 65% of stations in November to 98% of stations in March. During six months (Jan-Apr, Jun, and Dec) more than 90% of stations showed no trend in monthly average precipitation over the last 100 years.

The daily and hourly data will later be used to better understand high intensity storm events. Statistical analysis has yet to begin on that portion but it is the focus of future work.

Geological Society of America Abstracts with Programs. Vol. 56, No. 5

doi: 10.1130/abs/2024AM-402650

© Copyright 2024 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.