Date of Award
January 2025
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Geology
First Advisor
Taufique H. Mahmood
Abstract
The Prairie Pothole Region (PPR) of North and South Dakota is highly sensitive to climate variability, with its numerous depressional wetlands and shallow lakes responding dynamically to shifts in snow accumulation, melt, and evaporation. This study investigates the hydrological processes driving lake level fluctuations and watershed responses across 25 subbasins in PPR of North Dakota and South Dakota over a 23-water year (2001-2023) using the Cold Regions Hydrological Model (CRHM). Key state variables, including Snow Water Equivalent (SWE), open water evaporation, snowmelt runoff, and contributing area extent, were modeled to quantify the spatial and temporal variability of cold-region hydrology under changing climatic conditions. A distinct temperature gradient was noted, with warmer temperatures in southern and eastern subbasins resulting in decreased SWE and earlier snow melt. In contrast, cooler northern and western areas preserved higher SWE, postponing runoff and supporting spring flows. Evaporation, modeled using the Penman-Monteith approach, was highest in the southern and eastern PPR, driven by warmer temperatures. Results reveal distinct hydroclimatic periods, 2004-2008, 2009-2013, and 2014-2021, each dominated by different processes. The 2009-2013 period exhibited increased snowmelt-driven connectivity and extensive fill-and-spill runoff, whereas 2004-2008 and 2014-2021 were evaporation-dominated, leading to lake level declines and reduced contributing areas. By addressing a key regional-scale knowledge gap in PPR hydrology, this work enhances understanding of how climate variability translates into hydrological change, offering valuable insights for water resource management, landscape resilience planning, and the sustainability of recreational fisheries in the PPR.
Recommended Citation
Saha, Ayon, "Impacts Of Climate Variability On Cold Region Hydrologic Change In The Prairie Pothole Region" (2025). Theses and Dissertations. 7536.
https://commons.und.edu/theses/7536