Ryan J. MacDonald, Sarah Boon, and James M. Byrne
University of Lethbridge
MTCLIM, 2010
 Background and rationale
 Field techniques
 Modelling concepts
 Conclusions
It is a key environmental control, governing aquatic
ecosystem function.
1.
1.
2.
3.
2.
Dissolved oxygen
Metabolic rates
Species interaction
Fisheries management concerns
http://www.keepbanderabeautiful.org/climate-change.jpg
 “Are we spawning a generation of computer
hydrologists?” (Sidle, 2006)
 Few studies have quantified the energy and mass
balance components – particularly sub-surface
 Due to the complexities in energy and mass balance,
few fine-scale physically based spatial models exist
 Little is known about the potential impacts of
environmental change on stream thermal regimes
1.
Define key atmospheric and hydrologic variables
controlling stream temperature
2.
Incorporate reach-scale stream temperature mass and
energy balance into a watershed-scale spatial model
3.
Use the resulting model to assess how environmental
change (landscape disturbance and climate change) may
affect stream temperature regimes
Lethbridge
Shortwave Radiation
Longwave Radiation
Surface water flow
Surface water temp
Sensible heat flux Latent heat flux
Groundwater flow
Groundwater temp
F (streamflow)
Q* (net radiation)
Qh (sensible heat flux)
Qe (latent heat flux)
LOSING
GAINING
qin (G.W. flow)
Tw (stream temp)
Tin (G.W. temp)
Upstream flow – downstream flow = Net loss or gain
3 Sites:
Star Main – 1506 masl
Star East – 1575 masl
Star West – 1690 masl
Star_Main
Star_West
Star_East
9
Temperature (deg C)
8
7
6
5
4
3
2
1
0
15-May-10
17-May-10
19-May-10
21-May-10
23-May-10
Date
25-May-10
27-May-10
Star_Main
45
40
35
Stage (cm)
30
25
20
15
10
5
0
Star_West
Star_East
7
Star_East
9
y = 0.2106x + 2.4331
R² = 0.8413
Stream Temp (Deg C)
8
Star_Main
6
5
4
3
2
1
0
y = 0.1201x + 2.064
R² = 0.8056
8
7
6
5
4
3
2
1
0
-5
0
5
10
15
20
-5
25
0
5
Air Temp (Deg C)
10
9
y = 0.0667x + 2.3022
R² = 0.5109
8
7
6
5
4
3
2
1
0
-5
15
Air Temp (Deg C)
Star_West
Stream Temp (Deg C)
Stream Temp (Deg C)
9
0
5
10
15
Air Temp (Deg C)
20
25
20
25
 Uses a combination of empirical and physical modelling with
GIS derived hydrological response units (HRUs) to spatially
represent hydrometeorological variables
 air temperature
 precipitation
 Incoming radiation
 humidity
 evapotranspiration
 SWE
 interception
 sublimation
 melt
 soil water
 runoff
y = 0.9962x
R² = 0.9656
-25
-15
P< 0.0001
RMSE = 0.52
-5
5
15
Observed Tmean (Deg C)
350
25
Daily incoming radiation- Burned (2008)
300
250
Observed K
200
150
Simulated K
100
30 per. Mov. Avg.
(Observed K)
50
0
1
18
35
52
69
86
103
120
137
154
171
188
205
222
239
256
273
290
307
324
25
20
15
10
5
0
-5
-10
-15
-20
-25
Daily incoming radiation (Wm2)
Simulated Tmean (deg C)
Mean daily air temperature – Star Main (2007)
Day of year
dT (Change in temperature)
dx (Change in distance)
W (Stream width)
Q* (Net radiation)
Qh (Sensible heat flux)
Qe (Latent heat flux)
Qin (Groundwater flow)
Tin (Groundwater temperature)
Tw (Stream temperature)
F (Streamflow)
C (Specific heat capacity of water)
Leach and Moore, 2010
Scale?
 Stream temperature dynamics are complex in mountainous
environments
 Fine-scale surface/subsurface interactions likely dominate
the stream temperature energy and mass balance
 Incorporating process knowledge into a large-scale spatial
model may provide insight into which variables are
important at varied spatial and temporal scales
 Any good ideas??
 Funding sources – ACA, PARC, TU Canada, ASRD
(Forest Management Branch), AWRI, NSERC
 Uldis Silins , Chris Williams, Mike Wagner, Jeremy
Fitzpatrick and Jolene Lust from the U of A forest
Hydrology Lab
 Katie Burles and Dave Dixon from the U of L mountain
hydrology lab
 Dez Tessler – Field assistant