Correlating the effects of evapotranspiration changes to Lake Mead reservoir water inflow during the period 2000-2020
(2025) In Student thesis series INES NGEK01 20251Dept of Physical Geography and Ecosystem Science
- Abstract
- Warming due to global climate change has led to various natural anomalies, such as increases in forest fires, water level rise and droughts. A region being affected heavily by climate change is the Colorado River Basin, having an arid, semi-arid climate with the Colorado Mountain snowmelt supplying Colorado river, which flows throughout the basin, accumulating water in Lake Mead Reservoir. The Basin supplies water to millions of people, animals and plants, spanning 630,000 km2 and producing green electricity through many hydropower plants across its rivers, such as Hoover Dam, making its importance vital for modern infrastructure and nature. The relevant South-western megadrought, occurring since around 2000, is affecting extensive regions... (More)
- Warming due to global climate change has led to various natural anomalies, such as increases in forest fires, water level rise and droughts. A region being affected heavily by climate change is the Colorado River Basin, having an arid, semi-arid climate with the Colorado Mountain snowmelt supplying Colorado river, which flows throughout the basin, accumulating water in Lake Mead Reservoir. The Basin supplies water to millions of people, animals and plants, spanning 630,000 km2 and producing green electricity through many hydropower plants across its rivers, such as Hoover Dam, making its importance vital for modern infrastructure and nature. The relevant South-western megadrought, occurring since around 2000, is affecting extensive regions of US, including the Colorado River Basin, likely stemming from climate change induced warming and increased frequency and variability of La Niña events. One of the primary effects of climate change in many regions is the increase in instability of evapotranspiration, which stems from deviations of temperature and precipitation patterns, flora coverage and soil water retention. To quantify evapotranspiration, it can be split into potential evapotranspiration (PET) (a theoretical measure, reliant on temperature) and actual evapotranspiration (AET) (obtained through semi-realistic modelling, using PET, precipitation and soil water properties), with various methods of calculating both. Thornthwaite’s water balance model is one of the oldest and most reliable methods of obtaining these quantities over large areas of interest and is used in this study. With the increase of temperature, particularly PET, snowmelt follows, decreasing snowpack in the mountains which is a likely cause of decreased streamflow. Finally, Lake Mead water storage, gauge height and surface area data are used to compare with evapotranspiration to produce correlation statistics, which reveal significant negative relationships between changes in evapotranspiration and delayed Lake Mead inflow rate, with insignificant relationships with the direct storage, gauge height and surface area, with some relatively stronger relations with snowpack changes. Alternative method of calculating storage change instead of storage shows promising potential results. While the resulting data is conclusive, the great decrease of Lake Mead reservoir by over 60% during the 21-year study period shows a genuine threat to the Colorado River Basin and the South-Western US, promoting the need of continuing studies. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9201366
- author
- Businskis, Povilas LU
- supervisor
- organization
- course
- NGEK01 20251
- year
- 2025
- type
- M2 - Bachelor Degree
- subject
- keywords
- hydrology, water, reservoir, Lake Mead, Colorado River
- publication/series
- Student thesis series INES
- report number
- 692
- language
- English
- id
- 9201366
- date added to LUP
- 2025-06-17 15:49:29
- date last changed
- 2025-06-17 15:49:29
@misc{9201366,
abstract = {{Warming due to global climate change has led to various natural anomalies, such as increases in forest fires, water level rise and droughts. A region being affected heavily by climate change is the Colorado River Basin, having an arid, semi-arid climate with the Colorado Mountain snowmelt supplying Colorado river, which flows throughout the basin, accumulating water in Lake Mead Reservoir. The Basin supplies water to millions of people, animals and plants, spanning 630,000 km2 and producing green electricity through many hydropower plants across its rivers, such as Hoover Dam, making its importance vital for modern infrastructure and nature. The relevant South-western megadrought, occurring since around 2000, is affecting extensive regions of US, including the Colorado River Basin, likely stemming from climate change induced warming and increased frequency and variability of La Niña events. One of the primary effects of climate change in many regions is the increase in instability of evapotranspiration, which stems from deviations of temperature and precipitation patterns, flora coverage and soil water retention. To quantify evapotranspiration, it can be split into potential evapotranspiration (PET) (a theoretical measure, reliant on temperature) and actual evapotranspiration (AET) (obtained through semi-realistic modelling, using PET, precipitation and soil water properties), with various methods of calculating both. Thornthwaite’s water balance model is one of the oldest and most reliable methods of obtaining these quantities over large areas of interest and is used in this study. With the increase of temperature, particularly PET, snowmelt follows, decreasing snowpack in the mountains which is a likely cause of decreased streamflow. Finally, Lake Mead water storage, gauge height and surface area data are used to compare with evapotranspiration to produce correlation statistics, which reveal significant negative relationships between changes in evapotranspiration and delayed Lake Mead inflow rate, with insignificant relationships with the direct storage, gauge height and surface area, with some relatively stronger relations with snowpack changes. Alternative method of calculating storage change instead of storage shows promising potential results. While the resulting data is conclusive, the great decrease of Lake Mead reservoir by over 60% during the 21-year study period shows a genuine threat to the Colorado River Basin and the South-Western US, promoting the need of continuing studies.}},
author = {{Businskis, Povilas}},
language = {{eng}},
note = {{Student Paper}},
series = {{Student thesis series INES}},
title = {{Correlating the effects of evapotranspiration changes to Lake Mead reservoir water inflow during the period 2000-2020}},
year = {{2025}},
}