Cold Regions Hydrology and
Sustainable Water Management
John Pomeroy
Canada Research Chair in
Water Resources & Climate Change,
C t ffor Hydrology,
Centre
H d l
University of Saskatchewan, Saskatoon
and
Sean Carey (Carleton University)
Mike Demuth (Natural Resources Canada)
Richard Essery (Edinburgh University)
Masaki Hayashi
y
(University
(
y of Calgary)
g y)
Rick Janowicz (Yukon Environment)
Phil Marsh (Environment Canada, U of Sask)
Alain Pietroniro (Environment Canada, U of Sask),
Bill Quinton (Wilfred
(
Laurier University)
y)
Chris Spence (Environment Canada, U of Sask)
www.usask.ca/hydrology
Purpose of Talk
z
z
z
Show how water supplies in cold regions are
governed by the hydrological cycle
Show what is new in cold regions
g
hydrological
y
g
science that can be useful for sustainable water
management
Show how major hydrological changes are
threatening sustainable water management in
western and
d northern
h
C
Canada
d
z
z
Land cover change
Cli t change
Climate
h
Hydrological
y
g
Cycle
y
– elsewhere….
Where are the cold regions in Canada? Snow cover change over the year.
1 10 05
1 12 05
1 02 06
1 04 06
1 06 06
1 07 06
Permafrost in Canada
Cold Regions
g
Hydrological
y
g
Cycle
y
Precipitation
Snowfall
Sublimation
Blowing Snow
Ice
Evaporation
Rainfall
Evaporation
Snowmelt
Infiltration to
Frozen Ground
Lakes
Runoff
Interflow
Groundwater Flow
‘NATURAL’ FLOWS OF THE SOUTH
SASKATCHEWAN RIVER LEAVING ALBERTA
18 000 000 000
18,000,000,000
Annual Flow m3
16,000,000,000
14,000,000,000
12 000 000 000
12,000,000,000
10,000,000,000
8,000,000,000
6 000 000 000
6,000,000,000
4,000,000,000
2,000,000,000
0
1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Year
Highly variable
Natural and Actual Flow of South
Saskatchewan
Sas
atc ewa River
ve leaving
eav g Alberta
be ta
18,000,000,000
Natural
Annua
al Flow m3
16,000,000,000
Actual
14 000 000 000
14,000,000,000
12,000,000,000
10,000,000,000
8 000 000 000
8,000,000,000
6,000,000,000
4,000,000,000
2 000 000 000
2,000,000,000
0
1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Year
Natural flow: Decline of 1.2 billion m3 over 90 years (-12%)
Actual flow: Decline of 4 billion m3 over 90 years (-40%)
Note: 70% of decline due
d e to consumption,
cons mption 30% due
d e to hydrology
h drolog
Upstream consumption: 7%-42% of naturalized flows in last 15 years
Where does river flow come from?
z
Snowfall and Rainfall!
z
L k
Lakes,
wetlands,
tl d soilil water,
t groundwater,
d t
permafrost, snowpacks and glaciers are
merely
l ttemporary storage
t
reservoirs
i that
th t
are supplied by snowfall and rainfall and
either
ith store
t
precipitation
i it ti as water
t & iice,
evaporate back to the atmosphere, or
d i tto streams
drain
t
& rivers
i
Snowfall
Super-cooled cloud water droplets
form ice
Coalescence of crystals
Heavier snowfall on upslopes,
water to land transitions
Snowfall vs. rainfall. Depends on
air temperature and humidity
Blowing
g Snow Redistribution
Computer simulation of wind flow over mountains
Windspeed
Direction
3000
2500
2000
1500
1000
500
0
0
3 km
500
1000
1500
2000
2500
3000
Simulation of Hillslope Snowdrift
3 km
Snow Interception
S no
ow W ater E quivvalent m m
140
Forest
120
Clearing
100
80
60
40
20
0
North
South
East
West
4
snow load
15
12
9
6
3
0
3
-3
-6
-9
-12
-15
15
-18
-21
-24
27
-27
-30
-33
-36
-39
39
air temp
Intercepted
d snow load (mm) .
3.5
3
2.5
2
1.5
1
0.5
0
38
42
46
50
54
58
62
Julian Day
66
70
74
78
82
Air Tempe
erature (C) .
Interception & Sublimation of Snow
on a Hanging Tree
Snowmelt
Even though snowmelt is less than half of
the annual water applied to land or
glaciers it forms from 60% to 90% of runoff
g
z Snowmelt water can pass through
glaciers, soils, g
g
groundwater, lakes and
emerge as streamflow long after snowmelt
occurs
z Snowmelt causes flooding in some cold
regions
z
Snowmelt
z
z
z
Incoming solar
and thermal
radiation
Warm air
masses
Terrain and
vegetation
effects
Snow Energetics
g
Change in snow covered area and snow water
equivalent during melt at a tundra shrub site, Arctic
1 .0
14
SCA
12
10
SWE
0 .8
0 .6
8
6
4
2
0
1 6 /M a y
0 .4
T
S
S
T
u n d ra S W E
h ru b S W E
h ru b s n o w c o v e r a re a
u n d ra s n o w c o v e r a re a
2 0 /M a y
2 4 /M a y
D a te (2 0 0 3 )
0 .2
2 8 /M a y
0 .0
0 1 /J u n
Snow cov
vered area
Sn
now Water E
Equivalent (c
cm)
16
Cumula
ative Net R
Radiation MJ m-2
Net Radiation to Snowmelt on 25o Mountain
F
Forest
t Slopes,
Sl
Marmot
M
t Creek
C k
South Facing Forest Slope
Level & North Facing Forest Slopes
Level Clearing
Snowcover Depletion in Alpine Basins
08-May
Snow co
overed area (%)
02-Jun
100
75
North-east facing
slopes
p
50
South facing
slopes
25
0
01-May
21-May
10-Jun
30-Jun
20-Jul
09-Aug
Date
04 Jul
04-Jul
¾ Temporal snow cover depletion patterns
differ considerably between slopes within ~1
km2 cirque basin
¾ Single snow cover depletion curve cannot be
applied even for relatively ‘small’ scales in
mountain terrain
Water to Soils and Runoff Generation
f Streamflow
for
S
fl
over Frozen
F
Ground
G
d
Thermokarst – thaw of permafrost causing subsidence and landslides. We need to be able to predict W
d b bl
di
runoff for small streams
River crossings of roads (and pipelines) routinely fail because we have insufficient
because we have insufficient understanding of hydrology, runoff generation processes and permafrost or frozen d
f
f
ground in our designs. Soil Moisture and Snowpack
in a Tundra Mountain Valley
Soil Water Content %
100
50
40
50
30
20
10
0
0
50
100
North Face
150
200
250
300
350
Valley Bottom
1
400
South Face
0
100
500
50
300
100
0
0
50
100
150
200
250
300
350
400
0
Snow Water Equivalent mm
Snowmelt Runoff
500
100
400
300
50
200
150
100
0
0
50
100
North Face
150
200
250
300
Valley Bottom
350
400
South Face
100
50
0
0
50
100
150
200
250
300
350
400
1
0
Permafrost wetland runoff is controlled
b ffrostt table
by
t bl topography
t
h
a) 5 mm
b) 10 mm
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0.01
c)) 20 mm
(d) 35 mm
0
WT depth (m)
Average
g Flow in Bow River at Banff
snowmelt
lt in
i
mountains
What is the
source?
3
Flow rate
e (m /s)
150
100
50
0
3/2
4/1
5/1
6/1
7/1
8/1
8/31
9/30 10/31 11/30
Sources of Mountain Streamflow
z
z
z
Streamflow contribution related to glacier area
Study of Lake O’Hara (5% glacier cover on
Opabin Plateau)
Fl
Flow
to
t Lake
L k O’Hara
O’H
z
z
z
60% snowmelt
35% rainfall
5% glacier melt
Water Input to the Opabin Watershed
snow melt
glacier melt
flux
x (m3/s)
1.5
1
0.5
0
5/1
5/21
6/10
6/30
7/20
2006
8/9
8/29
9/18
10/8
Water Input to the Opabin Watershed
snow melt
glacier melt
rain
flux
x (m3/s)
1.5
1
0.5
0
5/1
5/21
6/10
6/30
7/20
2006
8/9
8/29
9/18
10/8
Lake O’Hara
O Hara Water Inputs and Output in
2006
snow melt
glacier melt
rain
stream flow
flux
x (m3/s)
1.5
1
0.5
0
5/1
5/21
6/10
6/30
7/20
8/9
8/29
9/18
10/8
Groundwater Discharge Rate
Controls Opabin Lake Water Level
0.8
4
Opabin Lake
Water Level
0.6
3
04
0.4
02
0.2
2
GW discharge
g
0
6/20
1
0
7/5
7/20
8/4
2006
8/19
9/3
9/18
Opab
bin WL (m abov
ve BM)
GW
W discha
arge (m 3 s -1)
snowmelt
Climate Change Predictions
Difference from 19801980-1999 to 20802080-2089
A1B – balanced scenario
Wetter and warmer, more to come!
IPCC 2007
Date of Spring Peak Streamflow in Northern
C
Canada
d
M k i Ri
Mackenzie
River at F
Fort Si
Simpson
150
Hay River at Hay River
Date of Annual Peak Discharge
210
Date of Annual Freshet Peak
July
180
Julia
an Day
Julian Day
Ma
May
120
June
150
April
May
90
1960
1970
1980
1990
Year
2000
120
1930
2010
1940
1950
1960
1970
Year
1980
1990
2000
2010
P
Permafrost
f t Decrease
D
30% iin 53 Y
Years
1947
5
2000
4
degreess C
3
2
1
0
-1
1
-2
1897
1907
1917
1927
1937
1947
Years
1957
1967
1977
1987
1997
Mountain High Elevation Snow Accumulation
in Spring
p g
450
Upper Bow Valley, 1 April
Snow survey @ 1580 m
400
SW
WE mm
350
300
250
200
150
100
50
0
1930
1940
1950
1960
1970
1980
1990
2000
2010
Snow-covered
SnowPeriod is Declining
in many places
Average change
(days/yr) in snow
cover duration in
the second half
(Feb.--Jul.) of the
(Feb.
snow year over the
period 19721972-2000.
Derived from the
NOAA weekly
satellite snow
cover dataset
Glacier Retreat in the Columbia Icefields
Mapped from
LANDSAT
satellite
Shrinking glaciers
release
l
water,
t
growing glaciers
store water
Glaciers are also a
valuable record of
climate variability
and change
Glacier Retreat – Satellite Analysis
LANDSAT satellite, 1975 and 1998.
z The decline of the total glacier area of the
North Saskatchewan basin between 1998
(306 km2) and 1975 (394 km2) was -22%
of g
glaciated area
z The decline of the total glacier area of the
South Saskatchewan basin between 1975
(138 km2) and 1998 (88 km2) was -36% of
glaciated area
z
Current Glacier Melt
Cont ib tion to River
Contribution
Ri e Di
Discharge
h ge
Fall
%
11.5
7.1
Fall
%
Annual
%
6.2
Mike Demuth, Natural Resources Canada
Annual
%
2.8
Deforestation
Snow
w in Fores
st / Snow in Clearin
ng
Effect of Forest Removal on Snow
A
Accumulation
l i
1
0.9
0.8
07
0.7
Sparsely Wooded
0.6
0.5
M di
Medium
D
Density,
it Y
Young
0.4
0.3
Dense Mature Canopy
Measured
0.2
Parametric Model
0.1
0
0
1
2
3
Leaf Area Index
4
5
Snowmelt Runoff Decreases with
Increasing Forest Cover
- infiltration to frozen soils –
60
50
40
Pine
Mixed-wood
Plantation
Clear-cut
Meltwater
30
Runoff (mm)
20
10
0
1994
1995
1996
Physically Based Hydrological Modelling
can answer water
t managementt questions
ti
Environment Canada Environmental
Prediction
P di ti F
Framework
k
Upper air
observations
GEM atmospheric
model
4DVar
data assimilation
CaPA:
C
PA
Canadian
precipitation
analysis
y
Surface
observations
CaLDAS:
C
Canadian
di
land data
assimilation
“ On-line”
mode
“ Off-line”
mode
Surface scheme
(EC version of
Watflood CLASS or
ISBA)
and routing model
MESH
Modélisation environnementale
communautaire (MEC)
de la surface et de l’hydrologie
IP3...
...is devoted to understanding water
supply and weather systems in cold
Regions
at high
R i
hi h altitudes
l i d andd high
hi h
latitudes (Rockies and western Arctic)
...will contribute to better prediction
of regional and local weather, climate,
and water resources in cold regions,
regions including ungauged basin
streamflow, changes in snow and water supplies, and calculation
of freshwater inputs to the Arctic Ocean
...is composed over about 40 investigators and collaborators from
Canada, USA, UK, Germany
…runs from 2006-2010
Concluding Remarks
z
z
z
z
z
z
Cold regions hydrology is very sensitive to both precipitation and
“energy” inputs
Snowpack, vegetation, permafrost, glaciers, wetlands, lakes and
groundwater all play an important role in governing streamflow in
cold regions
Physically--based computer models are having initial successes in
Physically
estimating these effects for water resource prediction
Changes in climate (wetter, warmer) are having complex effects on
cold regions hydrology – streamflow could go up or down depending
on latitude and complicating factors (pine beetle, permafrost thaw,
glacier melt
melt, gro
groundwater
nd ater depletion)
With dramatically increasing use of water from cold regions in
southern Canada, water managers will have to take into account
g g precipitation and energy
gy inputs and the cold
both the changing
regions hydrology processes with much greater precision in order to
manage the competing demands for limited water as the 21st
Century unfolds.
Our observation and hydrological modelling capacity will require
further development to meet the needs of precision water
management.
Thank You!
This research is supported by:
- IP3 Network, Canadian Foundation for Climate
and Atmospheric Science
-Alberta
Alb t IIngenuity
it C
Centre
t for
f Water
W t Research
R
h
-Natural Sciences and Engineering Research
Council of Canada
-Canada Research Chairs
-Canada Foundation for Innovation
-Environment Canada
-Natural Resources Canada
-Indian Affairs and Northern Development
Canada
-Biogeoscience Institute, Univ of Calgary
-Kananaskis Country,
-Nakiska Ski Area,
-Parks Canada
-Yukon Environment
-UK Natural Environment Research Council
-USDA Agricultural Research Service
-many others