An investigation of climatic controls in the
upper Laramie River watershed during
low stream flow years
Josh Heyer
with Dr. J. J. Shinker
Department of
Geography
PROPOSED RESEARCH PROJECT
Figure C. Surface Soil Moisture
Time-series plots of precipitation from the National Oceanic and Atmospheric
Administration (NOAA) will be constructed to identify drier-than-normal years from 1950 to
2010. Stream flow data from the United States Geologic Survey (USGS) National Water
Information System will be compared to five selected lower-than-normal precipitation years.
Based on the selected five years, composite anomalies will be calculated for surface
conditions and atmospheric controls using data from the National Center for Environmental
Prediction and National Center for Atmospheric Research (NCEP-NCAR) Regional
Reanalysis dataset. Analysis of how these climate components control spatial (e.g. local-toregional) and temporal (e.g. monthly-to-seasonal) variations via composite-anomaly maps
will establish how the variables contribute to drought conditions leading to low stream flow.
Data Analysis
2002 Proof of Concept
Stream flow data
Obtained from USGS Gage Site 06661585,
located near Bosler, Wyoming
(approximately 30 miles north of Laramie).
Normal Stream flow (example)
1998 156.9 cfs
Low Stream flow (example)
2002 18.9 cfs
Western U.S. Digital
Elevation Map
Time Series Plot for North Platte River,
U.S. Climate Division 10
Precipitation Anomalies
This study will investigate which
climate controls suppress precipitation
amounts and how these climate
controls are connected to low stream
flow years in the upper Laramie River.
Year
Hypothesis
During lower-than-normal stream flow
years in the upper Laramie River
watershed, large and small scale
climatic controls suppress precipitation
and regulate drought conditions.
Figure D. Precipitation Amounts at Surface
2002
Composite-anomaly maps for dry/low stream flow year 2002:
Figure A. 500 mb Geopotential Height
Higher than normal
Lower than normal
Figure A displays higher-than-normal heights
associated with a ridge in the atmosphere over
Wyoming and much of the U.S.
Figure B. 500 mb Omega
Rising motions
Sinking motions
Figure B shows patterns of sinking motions in the
atmosphere centered around Wyoming, which lead
to lower-than-normal precipitation (Figure D).
Lower than normal
Statement of the
Problem
Figure C displays patterns of low surface soil moisture content,
associated with suppressed precipitation amounts (Figure D) in
the upper Laramie River watershed for the year 2002.
Higher than normal
The upper Laramie River is located in
the drought-prone intermountain west.
During low stream flow years climate
controls at the surface (e.g. decreased
precipitation and soil moisture) and in
the atmosphere (e.g. sinking motions in
the atmosphere suppressing uplift of
moisture) can lead to decreased stream
flow in the Laramie River watershed.
Insight into how precipitation varies
allows for a better understanding of
how climatic controls are connected
with low stream flow years in this, and
potentially other watershed.
Lower than normal
Methods
Higher than normal
Introduction
Figure D shows lower-than-normal surface precipitation
amounts in the upper Laramie River for the year 2002.
Importance of Study
This study is important to water
management, agriculturalist, natural
resource managers, and populations
reliant on the water resources
provided by the Laramie River.
Furthering our understanding of how
climatic controls are associated with
low stream flow years and drought is
important for improving future water
management of the Laramie River.
Acknowledgments: I would like to thank Dr. Jacqueline
J. Shinker, the McNair Scholars Program: Zackie
Salmon, Susan Stoddard, Pilar Flores, and all my family
and friends for their support.
References available upon request: jheyer1@uwyo.edu