Characterizing rain/snow partitioning
in mountain watersheds for
present-day and future projected climates
Eric A. Sproles
Dr. Anne Nolin
Water Resources Graduate Program
Department of Geosciences
Oregon State University
2
3
4
5
Research Questions
Can we characterize sub-basins based upon SWE
and precipitation?
How will projected climate change affect this
characterization?
6
7
Snow Water Equivalence (SWE)
at Santiam Junction on April 1st
8
Concept of SWE/Pre
9
SWE/Pre and Degree Days
at Santiam Junction on April 1st
10
SWE/Pre and Degree Days
at Santiam Junction on April 1st
11
Model-based Approach
SnowModel (Liston and Elder, 2006)
With modifications for the Pacific Northwest by Sproles and Nolin
Landscape defined:
- Topography
- Landcover
Model Inputs:
- Meteorologic Data
Resolution:
- Grid resolution 100m
- Daily time steps
Outputs:
- SWE
- SWE melt
- Precipitation
- Runoff
12
~ 10 mm of snowpack
~ 6 mm of snowpack, 4mm of rain
+ its advective energy
Dai, 2008; USACE, 1956
13
15
16
17
Climate Perturbations
Temperature (°C)
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
2020s
1.22 0.99 1.11 0.99
1.01
1.28
1.59
1.60
1.37
1.00 0.83
1.17
2040s
1.99 1.75 1.90 1.74
1.68
2.13
2.79
2.72
2.50
1.86 1.56
1.94
2020s 0.01 0.16 2.04 1.30 -1.24 -5.87
-9.89
-9.78
-8.53
2.41 5.66
2.93
2040s 4.38 0.77 6.28 5.75 -0.56 -9.97
-15.45
-12.17
-12.51 6.94 8.11
5.53
Precipitation (%)
A1B Scenario – Economic Growth, new technologies, and balanced
energy production
Composite of 19 IPCC models downscaled to the Pacific Northwest
by the Climate Impacts Group at UW (Salathé and Mote)
18
20
21
Research Questions
- Can we characterize sub-basins based upon SWE
and precipitation?
- How will projected climate change affect this
characterization?
Next Steps
- Run for a longer time series
- Include a degree day component and hydrologic
data
- Finalize a probabilistic approach
22
http://sharnator.com - Toumei Mingen
23