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Global Terrestrial Network for Permafrost
Contributions to cryospheric and climate
monitoring
Sharon Smith
Geological Survey of Canada
Kananaskis, March 2, 2005
Permafrost is soil or rock that remains below 0°C throughout
the year
Permafrost is an important component of the cryosphere and an
integral part of the climate system
• variations in permafrost
temperatures can be a sensitive
indicator of climate change and
variability
• warming and thawing of permafrost
can have impacts on natural and
human systems:
– Permafrost variations have
implications for terrain stability,
hydrology, gas fluxes, infrastructure,
northern development and
ecosystems.
Permafrost is an important feature of the
northern landscape
Massive ice
Pingo
Patterned ground
Permafrost
affected peatlands
Presence of permafrost and ground ice presents challenges
to northern development
•
•
presence of permafrost and thaw settlement/frost heave considered in
design of infrastructure
techniques used to preserve infrastructure integrity
Foundation design for
permafrost environments
Thawing of massive
ice
Techniques to preserve
frozen ground
Utilidors
Warming and thawing of frozen ground can
lead to instabilities in the landscape
Unstable ground
Thawing of ground ice and
thermokarst terrain
Active layer
detachment
Damage to buildings
and infrastructure
Global Climate Observing System (GCOS) and the Global
Terrestrial Network for Permafrost (GTN-P)
• Key cryospheric variables for monitoring through WMO’s GCOS
– Active layer
– Permafrost thermal state
• GTN-P established under leadership of International Permafrost
Association (IPA) in 1999
• Provide long-term observations of active layer and permafrost
temperature that are required for:
– understanding the present permafrost conditions
– detection of terrestrial climate signal in permafrost and its temporal and
spatial/regional variability
– development and validation of permafrost, climate change and impact models
– assessment of carbon sources and sinks in permafrost regions
– northern development and land use decisions
– design of adaptation strategies to mitigate the impacts of climate warming in
permafrost
– improving our ability to provide ongoing, large area, timely assessment of
cryospheric change
GTN-P web site
gtnp.org
GTN-P Thermal monitoring sites
Circumpolar Active Layer Monitoring (CALM) Network
• 125 sites contribute to CALM
• Active layer thickness determined
through
– probing
– thaw tubes
– temperature measurements
• Measurements maybe done
– at points
– along transects
– on grids
Active layer, Mackenzie Delta
Thaw
depth determined from interpolation of
2.5
ground temperature profile at Baker Lake BH4
Ground surface
2
Thaw Depth (m)
Measurement of thaw settlement
1.5
1
Thaw depth
0.5
0
1997
1998
1999
2000
2001
2002
2003
Permafrost Thermal State
• Borehole monitoring
– few metres to several 100 m
deep
– frequency of measurements
varies from daily to monthly to
annual to several years
• Method
– Single probe
– Permanent multi-sensor cable
• manual measurements
• continuous measurements with
data loggers
Alert 15 m Trend 1994-2000 +0.15°C/yr
Manual Measurements
Alert BH5
Temperature (oC)
0
-10
-20
-30
.76m 4.57m
1990
1995
15.24m
High frequency data collection with data loggers
2000
Alert BH5
0
Borehole 5 July 2000 to August 2001
-5
Temperature Envelopes - Alert
-25
0
-20
Temperature ( C)
-15
-10
-5
0
Temperature (°C)
-10
o
-15
-20
0.762m
1.524m
-25
2.286m
Depth (m)
3.048m
4.572m
20
-30
7.62m
9.144m
15.24m
-35
01-Jul
40
60
BH1
BH2
BH3
BH5
31-Jul
30-Aug
29-Sep
29-Oct
28-Nov
28-Dec
27-Jan
26-Feb
28-Mar
27-Apr
27-May
26-Jun
26-Jul
25-Aug
Collection of Climate Data
Wrigley daily air temperature and snow depth
Air Temp
Wind Speed
Sep-03
Aug-03
Jul-03
Jun-03
May-03
Apr-03
Mar-03
Jan-03
Feb-03
Dec-02
25-09-03
25-08-03
25-07-03
25-06-03
25-05-03
25-04-03
25-03-03
25-02-03
25-01-03
25-12-02
25-11-02
25-10-02
0
Nov-02
10
Snow Depth
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
Oct-02
20
Air Temp
20
15
10
5
0
-5
-10
-15
-20
-25
-30
Alert
20
Air
0
-20
Temperature (oC)
30
Temperature (C)
40
Snow Depth (m)
50
Wind speed (m/s)
60
25-09-02
Temperature (c)
Wrigley monthly mean air temperature and wind speed
25
20
15
10
5
0
-5
-10
-15
-20
-25
-30
-35
-40
-45
-40
20
Ground Surface
0
-20
-40
BH3
July
2000
Sep
Nov
Jan
2001
Mar
BH5
May
July
Peatland site – Northern Alberta
16
Ground surface temperature Mackenzie Delta region
92TT1 Ground Surface Temperature
12
8
Ground surface
Temperature (°C)
4
Thaw depth
0
-4
-8
-12
-16
1995
1996
1997
1998
1999
2000
-20
Jan
Feb
Mar
Apr
May
Jun
Jul
Model validation
Analysis of trends in air and permafrost tempeature
Iqaluit Monthly Ground Temperature HT142
Iqaluit - Monthly ground temperatures at 5 m depth
-2
-4
-8
-10
-12
-14
12 month running mean air temp
Jul-01
Jan-02
Jul-00
Jan-01
Jul-99
Jan-00
Jul-98
Jan-99
Jul-97
Jan-98
Jul-96
Jan-97
Jul-95
Jan-96
Jul-94
Jan-95
Jul-93
Jan-94
Jul-92
Jan-93
Jul-91
Jan-92
Jul-90
Jan-91
Jul-89
Jan-90
Jul-88
Jan-89
-16
Jan-88
Temperature (°C)
-6
12 month running mean
Sep
Oct
Nov
Dec
Determination of onset of freezing and thawing
Evaluation of impact of warming
5m
Aug
High Arctic Observatories – Hydrocarbon Wells
• Deep temperature measurements
using single probe
• High frequency temperature
measurement to depths of 80 m
since 1991
• Data used to determine ground
surface temperature history
Alert
Gemini
Pat Bay
Marryatt
Data retrieval from Gemini
near Eureka
Grise Fiord
Resolute
Challenges of Arctic field work
Data retrieval from Pat Bay,
Lougheed Island
-15
-15.1
88 m
-15.2
High Arctic Observatories
•
•
-15.4
68 m
-15.5
67 m
58 m
-15.6
53 m
-15.7
-15.8
47 m
48 m
37 m
43 m
High resolution data collection
Development of ground surface
temperature histories through
application of mathematical
inversion techniques
32 m
-15.9
38 m
33 m
-16
1991
1992
1993
1994
1995
1996
1997
-15
65.75m
-15.1
Mean annual permafrost temperature
from Gemini, near Eureka
-15.2
Temperature (°C)
Temperature (°C)
-15.3
Mean annual permafrost temperature
from Pat Bay, Lougheed Island
-15.3
-15.4
35.75m
30.75m
25.75m
47.75m
-15.5
-15.6
-15.7
1990
20.75m
1991
1992
1993
1994
1995
1996
3.5
Gemini GSTH
-12
Reconstruction of Ground
Surface Temperature History
3
MAAT - Eureka Weather Station
GSTH - #175 - GSTH 1992 800-m manual log + 8 1-
2.5
2
MAAT (oC)
-14
-16
-18
-20
1.5
GSTH (°C)
• Inversion of deep logs for
hydrocarbon wells (Pat Bay and
Gemini) + inversion of shallow
temperature logs (1991-97)
1
-1.5
1500
Comparison of Gemini
and Pat Bay GSTH
1960
1970
1980
1990
2000
350
Total Snow (mm)
-0.5
-1
300
Total snow - Eureka
250
200
150
100
50
Environment Canada 2000a
0
1550
1600
1950
16501960 1700
1750
1970
1800
1980
1850
1900
1990
1950
2000
2000
4
3
GSTH (oC)
4
1950
0.5
0
o
+0.101 C/a
1977-98
o
-0.026 C/a
1950-76
-22
3
2
2
1
0
GSTH - #175 1992.35 manual log + 8 1-yr means cable 1991-97
GSTH - #175 1992.35 800-m cable
-1
GSTH (°C)
-2
1
1950
1960
1970
1980
1990
2000
Date (year)
0
Comparison of inversion of 800 m
log with inversion of 800 m log and
8 one year means for Gemini
-1
-2
-3
1800
FIG. 175-GSTH/CLIMATE
1820
1840
1860
1880
1900
Gemini
1920
Pat Bay
1940
1960
1980
2000
Alert – Ground Surface Temperature History Reconstruction
-10
BH1 48.8 m
-11
BH1 30.5 m
Temperature (°C)
-12
-13
BH3 57.3 m
-14
BH3 32.9 m
•
-15
BH2 54.8 m
GSTH determined from shallow (to
60m) temperature logs
Simultaneous inversion of 9 one
year means (1979-2000)
BH2 30.5 m
-16
80
85
90
95
00
•
3
2
3
2
1
0
GSTH (°C)
GSTH (°C)
1
-1
0
-1
-2
BH1
BH2
-2
BH3
BH1
-3
1950
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
-3
1800
1820
BH2
1840
BH3
1860
1880
1900
1920
1940
1960
1980
2000
Development of Remote Sensing Techniques
• Remote sensing techniques can potentially extend the
in situ measurements from GTN-P to the broader
spatial domain
• GTN-P can provide data for development and
validation of remote sensing techniques
• Information provided through remote sensing can
complement the in situ measurements and lead to for
example
– quantification of freeze-thaw states
– quantification of carbon budgets
– improved climate change impact assessments
Summary
GTN-P provides information that can be used to:
• Document and quantify fluctuation in permafrost conditions
• Improve understanding of cryosphere-climate processes
• Develop and validate permafrost-climate models
• Including improved representation of ground thermal regime in climate
models
• Development and validation of remote sensing techniques
0.0
-0.2
-0.4
Temperature °C
-0.6
-0.8
-1.0
-1.2
-1.4
Manners Creek 10 m
Petitot River 10 m
Table Mountain 12 m
Canyon Creek 12 m
-1.6
-1.8
-2.0
1984
1988
1992
1996
2000
Permafrost temperature
trends, Mackenzie Valley,
south of Norman Wells