Hydrologic and Related Environmental Changes in NW Canada: Mackenzie Delta Region
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Transcript of Hydrologic and Related Environmental Changes in NW Canada: Mackenzie Delta Region
Hydrologic and Related Environmental Changes in NW Canada: Mackenzie Delta Region
Philip MarshNational Water Research InstituteSaskatoon, Canada
Mackenzie R. basin
Beaufort Sea
Mackenzie Delta Region
treeline
Arctic Environmental Atlas
Alaska
- hydrology influenced by a complex suite of processes including:
- local climate, including temperature, snow, rain, radiation and wind for example.- runoff of the entire MRB;- Beaufort Sea;- changes in vegetation, with vegetation controlled in a complex manor by climate, fire, and possibly the grazing patterns of caribou and reindeer;
Objectives• Provide a few, brief examples of past changes in climate, vegetation
and hydrology in the Mackenzie Delta region over the past 40 years.
• In conjunction with observations of environmental change in this region, we have been carrying out detailed process and model validation studies to improve our understanding of the observed changes. This work has included a number of collaborators, including the Mackenzie GEWEX Study (MAGS) and the Climate Change Action Fund (CCAF).
Tra il Va lle y C k
Ha vikp a k C k.
M a c ke nzie Rive rEa st C ha nne l
C a b in C k.*
M a c ke nzie Rive rPe e l Rive r
Be a ufo rt Se a(3)
Trail Valley CreekMay 13, 1999
Havikpak CreekApril 30, 1999
Climate and hydrology during the last 40 years:
Ice Breakup in the Mackenzie Delta and Discharge of the Mackenzie River
Canadian Mean Temperature Trends (1950-98)
Winter Spring
Summer Autumn
B. Bonsal et al., NWRI
45
35
25
15
5
-5
-15
-25
-35
% ChangeSpring
Precipitation Change (1950-1998)
Summer Autumn
Winter
Barrie Bonsal et al., NWRI
Annual and Seasonal Mackenzie River Discharge
1960 1970 1980 1990
Observed
reconstructed
Dis
char
ge (m
m)
M. Mackay
Mackenzie at Arctic Red: Spring
-0.30-0.20-0.100.000.100.200.300.40
73 75 77 79 81 83 85 87 89 91 93 95
Norm
alised
Q
Mean Spring Q = 12910 cms SD =1775
Year
1950 1960 1970 1980 1990 2000
Pea
k w
ater
leve
l (m
asl
)
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
1950's
Julia
n D
ay
135
140
145
150
155
160
Annual peak level5-yr running meanBest fit line
May 20
May 25
May 30
June 4
June 91960's 1970's 1980's 1990's
Decadal mean
1950's
Mean = JD 152.5 = June 1 Date of Peak Water
levels
Elevation of peak water level
Mackenzie River East Channel at Inuvik
Year
1970 1975 1980 1985 1990 1995 2000 2005
Julia
n D
ay
130
140
150
160
170
180
190
200Mack. Peak flow E.C. Peak Level Col 1 vs Col 3
Date of East Channel Peak Water Level (Julian Day)
140 160 180 200D
ate
of M
acke
nzie
Riv
er a
t A
rctic
Red
Riv
er (J
ulia
n D
ay)
140
160
180
200
1:1
Date of peak discharge and peak water level is generally simultaneous between Mackenzie River at Arctic Red River
and East Channel at Inuvik
Climate and hydrology during the last 40 years:
Vegetation, snow and runoff in uplands to the east of the Mackenzie Delta
Ann
ual
-4
0
4
Tuktoyaktuk
InuvikA
utum
n
-4
0
4
Win
ter
-404
Spr
ing
-4
0
4
Year
1950 1960 1970 1980 1990 2000
Sum
mer
-4
0
4
(a)
(b)
(c)
(d)
(e)
-9.8oC
-8.9oC
-28.6oC
-13.3oC
11.5oC
Inuvik and Tuktoyaktuk air temperature
Ann
ual
0
100
200
300 Inuvik
Tuktoyaktuk
Aut
umn
0
100
Win
ter
0
50
Spr
ing
0
50
100
Year
1950 1960 1970 1980 1990 2000
Sum
mer
0
100
(a)
(b)
(c)
(d)
(e)
270
136
76
41
4618
4417
100
60
Inuvik and Tuktoyaktuk Precipitation
Increased shrub growth in the Mackenzie Delta Region
• J.R. Mackay presents numerous examples of increased shrub growth the areas north of Inuvik.
• For example, Mackay (1999) reported rapid increase in vegetation in drained lake bottoms since 1980.
• Similar increases observed at sites without drained lakes• Coincided with an increase in winter temperatures and
total snowfall
• However, there have few, if any, systematic studies of changes in vegetation in the Mackenzie Delta region over the last 40 years
Aug 28, 1976 Aug 13, 1993
18 years
J.R. Mackay,1995
Active layer thickness – 1968 to 1993
depressions
hummocks
0.0
1.4
SW
E (m
m)
0
50
100
150
200
250
peak SWEApril 15 SWE
Year1960 1970 1980 1990 2000
Dat
e of
pea
k S
WE
Mar/01
Apr/01
May/01
April 15
mean = 136 mm
Late winter snow cover
Year1950 1960 1970 1980 1990 2000
Dat
e
Apr 03
Apr 17
May 01
May 15
May 29mean = May 17
mean = April 28
air temp. first rises above 0Conset of continuous above 0C air temp. Estimation of the
start of spring melt
Apr 17
May 01
May 15
May 29
Jun 12
Cabin - onset of flowCabin - peak spring dischargeHavikpak - onset of flowHavikpak - peak spring discharge
Year
1980 1985 1990 1995 2000
Cab
in C
r.di
scha
rge
(m
3 /s)
0
10
20
30
Hav
ikpa
k C
r. di
scha
rge
0
1
2
3Cabin CreekHavikpak Creek
Cabin Creek
Apr 17
May 01
May 15
May 29
Jun 12
onset of flowpeak spring discharge
Year
1980 1985 1990 1995 2000
Dis
char
ge (m
3 /s)
0
2
4
6
8
10
Mean peak = May 23
Mean onset = May 16
Trail Valley Creek
Trail Valley Creek
Mean peak = May 29
Mean onset = May 21
Spring snowmelt runoff
Climate and hydrology of the Mackenzie Delta Region:
Process Studies
Trail Valley Creek: Shrub and Tundra Study Sites
Shrub site Tundra site
Shortwave radiation (daily average)
April/May 200321 28 05 12 19 26 N
et s
hortw
ave
(W/m
^2)
04080
120160200
Tundra snowShrub snow
Snow removed from shrub by end of Mayand at the shrub site during first week of
June
Mid-May 2003Mid-April 2003
April/May 200321 28 05 12 19 26 N
et lo
ngw
ave
(W/m
^2)
-100
0
100
200Tundra snowShrub snow
April/May 200321 28 05 12 19 26 N
et lo
ngw
ave
(W/m
^2)
-100
0
100
200Tundra snowShrub snow
Longwave (daily average)
Net Allwave (daily average)
Snow surface radiation
Climate and hydrology of the Mackenzie Delta Region:
Modelling
P-E (225 mm) S (-26 mm)
Qsfc (132 mm) Qtot (247 mm)
(P - E) - S - Qtot = error
(225) - (-26) -247 = 5 mm
CRCM est. of Annual basin water balance
Mackay et al. - MSC
P = 496 mmE = 271 mm
Mackenzie River 1998/99
measured: 2.68 x1011 m3
WATROUTE: 2.70 x1011 m3
WATFLOOD: 2.65 x1011 m3
Basin area = 1.8 million sq km.
Measured = 149 mmWATROUTE = 150 mmWATFLOOD = 147mm
Conclusion• Hydrologic and other environmental changes have occurred in the
MD over the last 40 years• These changes including warmer annual and spring air
temperatures, changes in precipitation and snow cover.• These have contributed to dramatic changes in the timing of spring
freshet and breakup, and in some areas increased shrub growth.• The links between climate, fire, vegetation and hydrology not well
understood• Ongoing process and modelling studies are making progress in
allowing us to better understand some of these past changes, and our ability to consider likely future changes