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Continued Permafrost Warming on the Arctic Slope of Alaska,
2014 Update
Gary Clow USGS/INSTAAR
Alaska Climate Divisions
Bieniek et al. (2014)
Statewide Air-Temperature Anomaly
5-yr running ave Bieniek et al. (2014)
dT = +0.9 K
5-yr running ave Bieniek et al. (2014)
Statewide Air-Temperature Anomaly
Arctic Slope Air-Temperature Anomaly
5-yr running ave Bieniek et al. (2014)
Sea Ice Extent
NSIDC/NOAA
Sep-2011
Air temperature reanalyses produced using the WRF model, 3.3-km resolution.
Warm Chukchi sector
Cool Chukchi sector
Cool NPR-A / Warm Arctic NWR
NE wind
A common pattern
Air-Temperature Patterns, Arctic Alaska
• With the juxtaposition of the Chukchi Sea, Beaufort Sea, and Brooks Range, weather and climate patterns are somewhat complicated on the Arctic Slope.
Chukchi Sea
Beaufort Sea ground temps
soil moisture
wind
snow depth
rainfall
air temp
radiation
telemetry USGS Climate-Station Network, Arctic Alaska
GTN-P
+1.63
+1.44
+0.70
+0.87
+0.27
+0.92
°C/decade
Mean-Annual Air-Temperature Trends Stations with at least 10 years of data
Chukchi Sea
Beaufort Sea
+1.63
+1.44
+0.70
+0.87
+0.27
+0.92
°C/decade
Mean-Annual Air-Temperature Trends Stations with at least 10 years of data
Chukchi Sea
Beaufort Sea
Seasonal Air-Temperature Trends Fish Creek 1992-2013
Atmosphere Active Layer (thaws in summer)
Permafrost
30 cm
+1.63 +1.86
+1.44 +1.62
+0.70 +1.48
+0.87 +0.66
na +1.46
+0.27 +0.36
+0.92 +0.65
°C/decade air active layer
Mean-Annual Active-Layer Temperature Trends Stations with at least 10 years of data
Fish Creek 1998-2013 Seasonal Ground-Temperature Trends
Active Layer (10 cm)
Maximum Active-layer Depth
Year
Dep
th (c
m)
Active-layer Freeze-up Date
Day
of Y
ear
Year
Snow Depth
winter trend +10.8 cm / decade
Snow
Dep
th (c
m)
Snow and Active-Layer
Fish Creek
Fish Creek Fish Creek
Chukchi Sea
USGS Deep-Borehole Array Thermal State of Permafrost
Beaufort Sea GTN-P
Chukchi Sea
USGS Deep-Borehole Array Thermal State of Permafrost
Beaufort Sea GTN-P
Permafrost Temperatures: South Meade Well
1980
1981
Permafrost Temperatures: South Meade Well
1983
Permafrost Temperatures: South Meade Well
1984
Permafrost Temperatures: South Meade Well
1989
Permafrost Temperatures: South Meade Well
2002
Permafrost Temperatures: South Meade Well
2007
Permafrost Temperatures: South Meade Well
Permafrost Temperatures: South Meade Well
2012
2012
20-m temps
Permafrost Temperatures: South Meade Well
+2.4°C warming since 1980 +2.9°C warming since 1989
1989 1980
Permafrost Temperatures Deep Borehole Array
ESN, Beaufort Coast +1.8°C
Dep
th (m
) Temperature (°C)
FCK, Coastal Plain
TLK, Chukchi Coast
Dep
th (m
)
Dep
th (m
)
Temperature (°C)
SME, Coastal Plain
Dep
th (m
)
Temperature (°C)
2012
2012
2012 +1.9°C
+2.4°C
2012
+2.9°C
Chukchi Sea
Permafrost Warming since 1990 (20-m depth)
Beaufort Sea
2.8 K
1.8 K 2.1 K
- 4.1
- 6.6
- 6.5 - 6.4
- 6.2
- 6.3
- 7.0 - 7.4
- 7.2 - 6.2
- 5.4
- 7.7
- 2.7 - 1.4
- 3.9
- 4.3
Current Permafrost Temperatures at 20-m Depth
Chukchi Sea
Beaufort Sea
Permafrost
Active Layer
Continuous Permafrost Discontinuous Permafrost
Permafrost Zones Alaska
Permafrost
Active Layer
Continuous Permafrost Discontinuous Permafrost
Tair = -8°C Tg = -5°C
mean-annual
Permafrost Zones Alaska
Current Permafrost Temperatures at 20-m Depth
Discontinuous Permafrost
Chukchi Sea
Beaufort Sea
Summary: • Air temperatures across the Arctic Slope are continuing to warm during the autumn.
• Active-layer temperatures are increasing during all seasons except summer.
- increased autumn air temperatures - thicker cold-season snowpacks
• Permafrost temperatures have warmed 2-3 K since 1990 and are continuing to do so. (1 K / decade)
• The discontinuous permafrost boundary is primed to jump north of the Brooks Range.
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