coupled modelling of soil thaw/freeze dynamics and runoff generation in permafrost landscapes, upper...
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Coupled modelling of soil thaw/freeze dynamics and runoff generation in permafrost landscapes, Upper Kolyma, Russia. Lebedeva L . 1, 4 , Semenova O. 2, 3 1 Nansen Environmental and Remote Sensing Centre 2 Gidrotehproekt Ltd 3 St. Petersburg State University 4 State Hydrological Institute - PowerPoint PPT PresentationTRANSCRIPT
Coupled modelling of soil thaw/freeze dynamics and runoff generation in permafrost landscapes,
Upper Kolyma, RussiaLebedeva L.1,4, Semenova O.2,3
1Nansen Environmental and Remote Sensing Centre2Gidrotehproekt Ltd
3St. Petersburg State University4State Hydrological Institute
St. Petersburg, Russia
The study is partially supported by Russian-German Otto Schmidt Laboratory for Polar and Marine research
Bare rocksBush tundra
Larch forest
Riparian vegetation
Variety of landscapes and complex process interactionsVariety of landscapes and complex process interactions
Deep active layerSubsurface runoff
Shallow active layer, surface runoff
www.hydrograph-model.ru
Motivation•variety of landscapes and dominated flow formation
mechanisms•sparse hydrometeorological network in North-Eastern Russia
and nearly absence of research stations•observed environmental changes impact differently in diverse
landscapes
- analysis of active layer formation and flow generation mechanisms in mountainous permafrost landscapes of the Kolyma Water Balance Station (North-Eastern Russia)
- simulate thaw/freeze depths and runoff in homogenious landscape typical for North-Eastern Russia using the Hydrograph model
- develop and verify unified approach for hydrological modelling in changing permafrost environments of North-East of Russia
Objectives
Study area: Kolyma water-balance station•Mean air temperature is -11,40С•Mean annual precipitation 320 mm•Elevation ranges 800-1700 m•Variety of landscapes •Continuous permafrost with the thickness up to 400 m•Representative for the vast territories of Upper Kolyma River Basin
Creek Area, km2
Average (and maximum) elevation, m
Average (and maximum) slope, º
Area occupied by a certain landscape, %
Rocky talus
Mountain tundra
Sparse trees
Forest and bogs
Morozova 0.63 1370 (1700) 33 (50) 98 2 0 0
Severny 0.33 1020 (1300) 21 (40) 24 63 0 13
Yuzhny 0.27 985 (1100) 17 (30) 5 17 56 22
Kontaktovy 21.2 1070 (1700) 25 (50) 34 27 12 27
List of measurements conducted at KWBS
Scheme of the typical landscapes
Bush tundra
Bare rocks
Sparse forest
Larch forest
The Hydrograph model
Process-based (explicitly includes all processes)
Observable parameters, no calibration (can be obtained apriori)
Common input daily data (air temperature and moisture, precipitation)
Free of scale problem (from soil column to large basin)
initially developed by Prof. Yury Vinogradovinitially developed by Prof. Yury Vinogradov
www.hydrograph-model.ru
Physical ground properties that drive the processes of active Physical ground properties that drive the processes of active layer formationlayer formation
www.hydrograph-model.ru
Moss andlichen
Peat Clay withinclusion of
rocks
Bedrock
Density, kg/m3 500 1720 2610 2610Porosity, % 90 80 55 35Water holding capacity, % 60 20-40 13 7Infiltration coefficient,mm/min
10 0.0005-0.5 0.0005 0.05-1
Heat capacity, J/(kg oC) 1930 1930 840 750Heat conductivity,W/(m oC)
0.8 0.8 1.2 1.5
Wilting point, % 8 6-8 4 2-3
Soil thaw/freeze processes and runoff formationSoil thaw/freeze processes and runoff formationType 1 – peaty soils and surface flowType 1 – peaty soils and surface flow
1 2 3 4 5 6 7 8 9
01.0901.0801.0701.0601.05
P (
mm
)
20
10
0
De
pth
(m
)
0
-0.2
-0.4
-0.6
-0.8
SW
E (
mm
)
100
80
60
40
20
0
T (d
egre
e C) 20
10
0IN
F (
mm
)
2 0
15
10
5
0
Q (
m3
/s)
0.05
0.04
0.03
0.02
0.01
0.00
Flo
w (
mm
)
20
15
10
5
0
observed runoffsimulated runoffsnow water equivalent
infiltration into soilsurface flowobserved soil thaw depthsimulated soil thaw depth
Peaty soil is fully saturated with ice during snow melt. It thaws slowly and surface flow occurs.
moss and lichen
peat
bedrock
clay inclusion of rocks
100
90
80
70
60
50
40
30
20
10
cm
Larch forestSparse forest
Bush tundraBare rocks
Soil thaw/freeze processes and runoff formationSoil thaw/freeze processes and runoff formationType 2 – rocky stratum and subsurface flowType 2 – rocky stratum and subsurface flow
1 2 3 4 5 6 7 8
01.0901.0801.0701.06
P (
mm
)
30
20
10
0
De
pth
(m
)
0.0
-0.5
-1.0
Wa
ter
de
pth
(m
m)
200
150
100
50
0
T (d
egre
e C)
20
15
10
5
0
Ice
co
nte
nt
(mm
) 2 50
200
150
Q (
m3
/s)
0.25
0.20
0.15
0.10
0.05
0.00
observed runoffsimulated runoffsnow water equivalent
liquid water content in soilice content in soilsimulated soil thaw depth
moss and lichen
peat
bedrock
clay inclusion of rocks
100
90
80
70
60
50
40
30
20
10
cm
Larch forestSparse forest
Bush tundraBare rocks
Snowmelt water is re-frozen in soil. Only subsurface flow is formed.
Stages of the soil thawing and spring flow formation (Bantsekina, 2003)
Data of ice content in the rocky stratum don’t exist. According to literature each year in freshet period 40-60 mm ground ice are formed. Modelling results for 1969-1990 show 21-48 mm.
flow dependence on air temperature
Observed and simulated thawing depths in bare rocks, bush tundra and larch forest, 1962
Bush tundra
Bare rocks
Larch forest
Runoff modelling at slope scaleRunoff modelling at slope scaleYuzny Creek,
area 0.27 km2 , sparse forest
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Severny Creek, area 0.33 km2, bush tundra
1 – observed runoff, 2 – simulated runoff, 3 - precipitation
1978: NS = 0.86
1980: NS = 0.74
1 2 301.0901.0801.0701.06
P,
mm
50
0
F,
mm
80
60
40
20
0
14
Kontaktovy Creek, 21.2 km2, 1978, m3/s
Наблюденный Рассчитанный
10.197808.197806.197804.1978
м3/с
8
6
4
2
0
Наблюденный Рассчитанный
10.197808.197806.197804.1978
м3/с
8
6
4
2
0
Morozova Creekarea 0.63 km2,bare rocks
Landscape distribution:Bare rock – 32 %Bush tundra – 29 %Sparse forest – 21 %Larch forest – 18 %
1 – observed runoff, 2 – simulated runoff, 3 - precipitation
Runoff modelling at slope and small scaleRunoff modelling at slope and small scale
1979: NS = 0.79
1978: NS = 0.85
•Hydrograph model proved its capability to successfully describe soil thawing and freezing, water and ice dynamics in rocky stratum in diverse landscapes based on relatively simple algorithms and observable parameters.
•Good agreement between observed and simulated active layer depth and runoff is achieved for small watersheds of the KWBS
•Developed set of model parameters which are systematized according to main landscapes of the Upper Kolyma River basin might be transferred to other basins without specific observations
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Conclusions
Semenova O., Lebedeva L., Vinogradov Yu., 2013 Simulation of subsurface heat and water dynamics, and runoff generation in mountainous permafrost conditions, in the Upper Kolyma River basin, Russia. Hydrogeology Journal vol. 21, iss. 1, 107 – 119. DOI:10.1007/s10040-012-0936-1
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Thank you for attention