Transcript Modelling of near-surface permafrost and hydrological

Modelling of near-surface permafrost
and hydrological processes across
different scales and landscapes
Lebedeva L.1,4, Semenova O.2,3
1Nansen
Environmental and Remote Sensing Centre
2Gidrotehproekt Ltd
3St. Petersburg State University
4State Hydrological Institute
St. Petersburg, Russia
Variety of landscapes and complex process interactions
Bare rocks
Bush tundra
Deep active layer
Subsurface runoff
Larch forest
Riparian zone
Shallow active layer, surface runoff
www.hydrograph-model.ru
Two possible mechanisms of snowmelt water dynamics in
permafrost zone of North-Eastern Russia
Bare rocks
Riparian zone
Subsurface flow
Ground ice formation
Surface flow
Motivation
• Water fluxes in permafrost zone are highly variable in space and
time and interrelate closely with seasonal thawing and freezing.
• Modelling of active layer dynamics and hydrological processes
could not be performed separately and requires explicit accounting
for both heat and water fluxes in seasonal thawing layer.
• Large remote Arctic territories still lack any observations.
Transferable across space, scales and time modelling approaches are
needed
Goal
Developing a multi-scale approach to simulate nearsurface permafrost and hydrological processes that can be
applicable at scales from a soil column to a large river basin
Methodology
Parameters –
properties of the
basin
Algorithms & parameters adjustment on:
• point observations of soil freeze/thaw
• slope scale homogeneous watersheds
Hydrological
model
Verification on large
poorly-gauged basins
Parameterization
scheme
multi-scale modelling approach
for near-surface permafrost and
hydrological processes
5
The Hydrograph model
 Process-based (explicitly
describes all processes)
 Observable parameters,
no calibration (values can be
obtained apriori)
 Common daily data input
(air temperature and moisture,
precipitation)
 Free of scale problem
(from soil column
to large basin)
initially developed by Prof. Yury Vinogradov
www.hydrograph-model.ru
Study objects: three research sites in Russian permafrost
zone
Igarka research site,
Lower Yenisei River
Kolyma station,
Upper Kolyma River
Bomnak station,
Amur River basin
Study objects: three research sites in Russian
permafrost zone
Igarka site
Bomnak station
Kolyma station
-8°C
-5.1°C
-11.4°C
510 mm/year
590 mm/year
320 mm/year
30-100 m
300-500 m
800-1700 m
Landscapes
Birch and spruce
forest, raised bogs
Larch, pine, birch
forest; mires
Bare rocks, sparse,
larch forest
Permafrost
Discontinuous
Unmerging
Continuous
MAAT
Precipitation
Altitudes
Landscape control on permafrost presence in Igarka:
1) Deciduous forest – no permafrost;
2) Coniferous forest – deep active layer;
3) Raised bogs – shallow active layer
1
2
3
Simulated ground temperature in different landscapes, Igarka:
1 - Deciduous forest on mineral well-drained loams with thin
organic layer lacks permafrost
3 - Raised bogs with 30 cm moss layer and permanently wet peaty
soil has active layer up to 50-60 cm.
cm
1
3
- soil thaw depths at the CALM site, averaged across landcover type “tundra on peat”
Observed and simulated flow in Graviyka River basin, 323 km2
Results for the wettest (1971) and driest (1976) years, for the years
with highest (1972) and lowest (1985) Nash-Sutcliffe efficiency (NS)
Scheme of the typical landscapes for the Kolyma basin
Bare
rocks
Bush
tundra
Sparse Larch forest
forest
Physical ground properties that drive the processes of active
layer formation
Density, kg/m3
Porosity, %
Water holding capacity, %
Infiltration coefficient,
mm/min
Heat capacity, J/(kg oC)
Heat conductivity,
W/(m oC)
Wilting point, %
Moss and
lichen
Peat
Bedrock
1720
80
20-40
0.0005-0.5
Clay with
inclusion of
rocks
2610
55
13
0.0005
500
90
60
10
1930
0.8
1930
0.8
840
1.2
750
1.5
8
6-8
4
2-3
www.hydrograph-model.ru
2610
35
7
0.05-1
Kolyma station
Bare rocks
80
Observed and simulated
river runoff, mm
0
50
P, mm
Observed and simulated
seasonal thaw depth, m
F, mm
60
40
1979 г.
20
0
Bush tundra
01.06
01.07
01.08
1
2
01.09
3
1978 г.
Larch forest
1980 г.
1 – observed, 2 – simulated, 3 - precipitation
Larger poorly-gauged basins of North-Eastern Siberia
Results of runoff modelling at poorly gauged basins in NorthEastern Russia
The Ayan-Yuryakh river, 9560 км2, 1978-1979, Upper Kolyma River, m3/s
1200
1000
1000
800
800
м3/с
1200
600
600
400
400
200
200
0
0
05.1978
07.1978
Наблюденный
11.1978 05.1979
09.1978
07.1979
Наблюденный
Рассчитанный
09.1979
11.1979
Рассчитанный
The Tenke river, 1820 км2, 1978-1979, Upper Kolyma River, m3/s
400
350
350
300
300
250
250
м3/с
400
200
200
150
150
100
100
50
50
0
0
05.1978
07.1978
Наблюденный
09.1978
Рассчитанный
05.1979
11.1978
07.1979
Наблюденный
09.1979
Рассчитанный
Mountainous relief and absence of meteorological stations. Input data
were interpolated from
stations located outside the basins
www.hydrograph-model.ru
11.1979
Results of runoff modelling at poorly gauged basins in
North-Eastern Russia
The Suntar River, 7680 km2, 1959-1962, Upper Indigirka River, m3/s
Conclusions
- near-surface permafrost and hydrological processes are
closely related to the observable landscape properties
- explicit implementation of this relation into models is a
proper basis of simulation of ground thaw and runoff generation
across different scales
www.hydrograph-model.ru
Acknowledgements:
The authors acknowledge the support of the EUCOP4 organizers and PYRN in
attending the Conference
Various help and data sharing from the Igarka Geocryology Lab is very much
appreciated
Thanks for your attention!
Obrigado pela sua atenção!
Permafrost influence on the river runoff in two small
permafrost and non-permafrost adjusted basins, Amur
River basin
Period I “Frozen”
• Frozen ground
• No water losses
• Uniform flow in
two watersheds
Period II “In transition”
Peakflow rate is
decreasing with ground
thawing in nonpermafrost basin
Period III “thawed”
• No frozen ground, large
water losses and low
streamflow in non-permafrost
basin
• High flow with peaks in
permafrost watershed