T265 Geologic Research in the Cascades: Understanding Glacier Change, Geologic Hazards, and Mountain Hydrology along an Active Margin in a Changing Climate (Posters)

Wednesday, 25 September 2024
8:00 AM - 5:30 PM
Hall D

EVALUATING THE EFFECT OF AIR TEMPERATURES ON SUSPENDED SEDIMENT IN THE WHITE RIVER, WA

Paper number: T265-9
Program: Technical Sessions
Time: 8:00 AM – 5:30 PM

Authors

  • Jose Garcia Presenting Author
    California State University San Bernardino, San Bernardino, CA
  • Claire Todd
    California State University San Bernardino, San Bernardino, CA

Abstract

Glaciated peaks release high sediment loads into the meltwater streams they produce. Meltwater from Emmons Glacier on Mount Rainier flows into the White River, a tributary of the Puyallup River in Washington State. This study analyzes the effects of air temperature on suspended sediment concentrations (SSCs) and turbidity in the White River. Over two 48-hour periods in July 2023, we collected glacial meltwater emerging from the terminus of Emmons Glacier, and monitored water level, air temperature, and turbidity using a pressure transducer, handheld weather station, and a multiparameter probe, respectively. During one 48-hour period, we also collected glacial meltwater ~ five km downstream using an autosampler. The glacial meltwater samples were filtered, and the dried suspended sediments were weighed to determine the average SSC at each sample time. We compared these data with turbidity data from USGS stream gages located approximately 112 km downstream of Emmons Glacier. Our results show that diurnal peak air temperatures coincided with the peak weights of sediment per unit volume at the glacier terminus; the minimum SSCs at the terminus occurred in the morning when air temperatures are cooler. We measured a 70-75 percent increase between diurnal minimum and maximum sediment load. Over the same time period, USGS stream gages capture diurnal peaks in discharge and turbidity indicative of glacial influence, and a lag between peak discharge and peak turbidity. Our results suggest that glacially-derived suspended sediment concentrations in the White River are sensitive to air temperatures, and that glacial change may impact sediment supply to downstream locations.

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

doi: 10.1130/abs/2024AM-405270

© 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.