Permafrost

Cryosphere
This indicator shows trends in permafrost temperature at select sites in Alaska.

Figures

Figure 1. Permafrost Temperatures in Alaska, 1978–2023

Data source: University of Alaska Fairbanks, 2024
Web update: December 2024

Figure data (CSV) EPA source data (CSV)

This figure shows permafrost temperature at borehole sites in interior and northern Alaska, measured at the end of summer (approximately September of each year). Measurements at these sites were taken at depths between 49 and 85 feet.

Show the data behind this figure
Year Livengood C’uul C’ena’ (Gulkana) Birch Lake Old Man T’eedrinjik (Chandalar Shelf) Deenaalee (Healy) Troth Yeddha’ (College Peat) Coldfoot West Dock Deadhorse Franklin Bluffs Happy Valley Galbraith Lake Utqiagvik (Barrow) Qaaktugvik (Kaktovik)
1978 NA NA NA NA NA NA NA NA 13.91000 16.37600 NA NA NA NA NA
1979 NA NA NA NA NA NA NA NA NA 16.88000 NA NA NA NA NA
1980 NA NA NA NA NA NA NA NA 14.75600 16.88000 NA NA NA NA NA
1982 NA NA NA NA NA NA NA NA NA 17.33000 NA NA NA NA NA
1983 30.79580 30.20720 NA NA NA NA 27.3452 NA 14.75960 17.37140 20.33600 22.94420 NA NA NA
1984 NA 30.16220 NA 26.25800 NA NA 27.4298 29.4818 14.25380 16.84400 20.08760 22.61120 NA NA NA
1985 NA 30.18740 NA 26.16800 27.2120 29.9084 NA 29.4098 14.18000 16.84760 19.83200 22.56620 21.98120 NA NA
1986 NA NA 28.43780 26.11040 27.0842 NA NA NA 13.96220 17.32280 19.66640 22.45640 21.81560 NA NA
1987 NA 30.23960 28.59260 26.16800 27.3344 NA 27.3758 29.0948 14.23760 16.94300 19.52060 22.40960 21.74900 NA NA
1988 NA 30.24320 28.57820 26.23100 27.5360 NA 27.2876 29.0930 14.38160 17.00420 19.51340 22.50320 21.85700 NA NA
1989 NA 30.24320 28.54220 26.38400 27.7340 NA 27.3650 29.1524 14.66240 17.44700 19.50620 22.59680 22.10360 NA NA
1990 NA 30.29720 28.56020 26.22200 27.7214 NA 27.3776 29.2334 14.92340 17.72420 19.74560 22.71740 22.05320 NA NA
1991 NA 30.36920 28.90040 26.37500 27.5414 NA 27.5684 29.1218 14.96480 17.93120 19.81040 22.62920 21.70220 NA NA
1992 NA NA NA 26.50100 27.4694 NA NA 29.1830 14.82980 18.02300 19.92920 22.74260 21.87140 NA NA
1993 30.66798 30.52040 29.18300 26.48660 27.3992 30.3044 28.0292 29.1434 14.65700 17.95100 19.94000 22.88300 22.05140 NA NA
1994 30.68958 30.57800 29.37920 26.82140 27.7844 30.3962 28.1624 29.2172 14.94140 18.21920 20.13260 22.99640 22.17560 NA NA
1995 30.70128 30.64280 29.50160 27.03380 27.9230 30.4790 28.1894 29.3720 15.11060 18.35060 20.15960 22.95680 22.22505 NA NA
1996 30.70848 30.68420 29.45480 27.01580 28.0202 30.5564 28.1318 29.5250 15.41840 18.73760 20.22980 23.13140 22.41093 NA NA
1997 30.70670 30.72614 29.27592 26.76763 28.0454 30.5744 27.9176 29.5160 15.60319 19.12858 20.50639 23.31010 22.70174 NA NA
1998 30.66980 30.73217 NA 26.99524 28.0742 30.6068 27.8168 29.4980 15.82043 19.55779 20.75000 23.50742 22.95684 NA NA
1999 30.64629 30.69720 NA 27.20260 28.1300 30.6410 NA 29.5250 16.23232 19.97407 21.02151 23.72108 23.15667 NA NA
2000 30.62809 30.68672 NA 27.14875 28.6160 30.5510 27.6368 29.5448 16.55071 20.05045 21.26691 23.80636 23.03197 NA NA
2001 NA 30.69514 29.37054 27.26316 28.4738 30.5168 27.6584 29.5322 16.49446 19.97893 21.31365 23.72464 23.10463 NA NA
2002 NA NA 29.40807 27.34160 28.3856 30.4844 NA 29.4890 16.52729 20.12301 21.25400 23.62735 23.14220 NA NA
2003 NA NA NA NA NA NA NA NA NA NA 21.34040 NA 23.18000 15.6740 NA
2004 NA NA NA NA NA NA NA NA NA NA NA NA NA 15.8180 NA
2005 30.63200 NA NA 27.66200 28.7510 NA 27.7124 NA 16.72340 20.26760 21.34760 23.79398 22.87400 15.9440 NA
2006 NA NA NA 27.78800 28.8014 NA 27.8024 29.8076 16.79936 20.21047 21.37059 23.84960 22.87544 NA NA
2007 30.63560 30.71660 29.44760 27.84200 28.7888 NA 27.8042 29.9246 17.12120 20.55740 21.46640 23.84960 23.02520 16.1600 NA
2008 30.63740 NA 29.15600 27.59180 28.8698 30.4664 27.5954 30.0002 17.06180 20.35580 21.46280 23.79380 22.91360 16.1600 16.4030
2009 30.60500 30.67520 29.04980 27.51440 28.8950 30.4664 27.5954 29.9750 17.29940 20.49980 21.40700 23.68400 22.96940 16.1906 NA
2010 30.59420 30.67700 29.02460 27.38480 28.8428 30.4376 27.4244 30.0254 17.24180 20.72840 21.63200 23.90360 23.30060 16.3418 16.4084
2011 30.58700 30.67700 29.02460 27.43700 28.8446 30.3962 27.4892 29.9732 17.53700 21.01100 21.74360 24.12140 23.52020 16.5056 16.5830
2012 30.58700 30.70940 28.99760 27.64760 28.9472 30.3836 27.3848 30.0254 17.53700 21.01100 21.96860 24.28520 23.68400 16.6046 16.6424
2013 30.58700 30.72740 28.81040 27.62060 28.9472 30.3836 27.3830 30.1424 17.65580 21.23780 21.96860 24.17540 23.68400 16.6424 16.6730
2014 30.61220 30.72920 28.99940 27.46940 28.8446 30.4700 27.3830 NA 17.89160 21.46280 22.08020 24.23120 23.84960 16.7018 16.7612
2015 30.63740 30.74180 29.24600 27.73760 28.9472 30.5618 27.5450 29.8724 18.19580 21.93980 22.30340 24.42020 24.04400 16.8224 16.8818
2016 30.65180 30.77240 29.63120 27.80600 29.1560 30.6140 27.7538 29.9246 18.37220 21.91820 22.53200 24.77840 24.39860 17.0114 17.0726
2017 30.68960 30.79040 29.82740 27.91040 29.2064 30.6140 27.9626 29.9336 18.60620 22.08740 22.58780 24.94040 24.34460 17.0726 17.1914
2018 30.69680 30.81740 30.05240 28.14440 29.3108 30.6392 28.1156 29.9246 18.88160 22.42040 22.69760 24.94040 24.45260 17.2040 17.2922
2019 30.71120 30.81740 30.18020 28.61060 29.4116 30.6626 28.2722 30.0254 19.14800 22.63280 22.91000 25.14920 24.77120 17.4110 17.5298
2020 30.72560 30.82640 30.30800 28.83020 29.5646 30.6878 28.4288 NA NA 22.63280 23.07560 25.30940 24.82520 NA NA
2021 30.74360 30.85160 30.35840 28.75280 29.6168 30.7400 28.5332 30.3332 19.18760 22.35560 23.13140 25.22840 24.39140 17.8250 NA
2022 30.73460 30.88580 30.45920 28.45490 29.5142 30.7652 28.5836 30.4214 18.88160 22.18820 23.07560 25.12220 24.06380 17.8250 17.8250
2023 30.73460 NA 30.50960 28.50710 29.4620 30.8156 28.5332 NA 18.85100 22.29980 23.13140 25.09520 23.98460 17.8250 17.8844

Figure 2. Changes in Permafrost Temperatures in Alaska, 1978–2023

Data source: University of Alaska Fairbanks, 20245
Web update: December 2024

Figure data (CSV) EPA source data (CSV)

This map shows the change in permafrost temperature per decade for long-term borehole sites in Alaska. Larger circles correspond to greater rates of warming per decade. The blue circle represents a cooling trend. Borehole measurement depths range from 49 to 85 feet.

Show the data behind this figure
Site Native name Region Depth (m) Latitude Longitude Elevation (m) Change (°F per decade)
Deadhorse Northern Alaska 20 70.16°N 148.47°W 17 +1.46
West Dock Northern Alaska 20 70.37°N 148.55°W 3 +1.27
Kaktovik (ANWR / Barter) Qaaktugvik Northern Alaska 20 70.12°N 143.63°W 12 +1.10
Barrow 2 (N. Meadow Lake No.2 / NML-2) Utqiagvik Northern Alaska 16 71.31°N 156.66°W 5 +1.10
Franklin Bluffs Northern Alaska 20 69.67°N 148.72°W 88 +0.93
Galbraith Lake Northern Alaska 20 68.48°N 149.50°W 823 +0.76
Happy Valley Northern Alaska 20 69.16°N 148.84°W 319 +0.71
Chandalar Shelf T’eedrinjik Interior Alaska 20 68.07°N 149.58°W 976 +0.62
Old Man Interior Alaska 15 66.45°N 150.62°W 390 +0.62
Birch Lake Interior Alaska 15 64.32°N 146.69°W 262 +0.37
Coldfoot Interior Alaska 26 67.24°N 150.16°W 335 +0.31
College Peat Troth Yeddha’ Interior Alaska 20 64.87°N 147.78°W 137 +0.16
Gulkana C’uul C’ena’ Interior Alaska 15 62.17°N 145.47°W 479 +0.16
Healy Deenaalee Interior Alaska 15 63.88°N 149.25°W 673 +0.11
Livengood Interior Alaska 15 65.51°N 148.60°W 179 -0.01

Key Points

  • Between 1978 and 2023, permafrost temperatures increased at 14 of the 15 borehole sites shown in this indicator (see Figures 1 and 2). Warming was statistically significant at all 14 of the boreholes that had increases.
  • In general, permafrost has warmed more quickly in northern Alaska than interior Alaska (see Figure 2). The increasing rate of change in the north is consistent with changes in air temperatures, which have increased more quickly in northern Alaska than in other parts of the state4 (see Figure 3 of EPA’s U.S. and Global Temperature indicator).
  • The Deadhorse site in northern Alaska had the highest rate of temperature change, at +1.5°F per decade. The Livengood site in interior Alaska was the only site to get cooler over the period of record, though only slightly. Overall, permafrost temperatures have increased at an average rate of 0.6°F per decade.
  • Changes in permafrost temperature shown in this indicator are consistent with changes observed in Russia, Canada, and other parts of the Arctic.1

Background

Permafrost is defined as rock or soil that remains at or below the freezing point of 32°F for two or more years. Permafrost usually lies below an “active layer” of ground that freezes and thaws every year with seasonal changes in temperature.1 Permafrost occurs in many different forms with various amounts of ice (continuous and discontinuous) and is mainly found in areas near the Arctic. In Alaska, about 80 percent of the ground has permafrost underneath it.2 A key characteristic affecting the state of permafrost is the temperature at the ground surface and shallow depths. The seasonal timing, amount, and extent of snow cover (see the Snow Cover indicator) also affect permafrost.3 A warming climate has brought higher temperatures to Alaska and other areas with permafrost, causing some permafrost to thaw. While the impacts of climate change on permafrost vary at regional and local scales, permafrost thawing has been observed in many locations around the world.

A thawing permafrost layer can lead to severe impacts on people and the environment. For instance, as ice-filled permafrost thaws, it can turn into a muddy slurry that cannot support the weight of the soil and vegetation above it. Infrastructure such as roads, buildings, and pipes could be damaged as permafrost thaws.4 Infrastructure damage and erosion, due in part to permafrost thaw, has already caused some communities in western and southern Alaska to have to relocate. Additionally, organic matter (like the remains of plants) currently frozen in the permafrost will start to decompose when the ground thaws, resulting in the emission of methane and carbon dioxide into the atmosphere. This contributes to further global climate change.1

About the Indicator

For more than 40 years, a group of scientists from the University of Alaska Fairbanks has been studying permafrost across Alaska. They measure temperature every year in 15 boreholes drilled at least 50 feet deep and analyze the data for long-term trends. This data set provides valuable information about how rapid climate changes observed in Alaska are influencing permafrost. Because permafrost temperatures can also be influenced by land use change such as urban development, agriculture, and other human activities, this indicator focuses on a select set of boreholes that are relatively remote and undisturbed for better assessment of changes associated with climate. Figure 1 shows temperature measurements for each borehole site in the interior and northern Alaska regions. Figure 2 shows the long-term rate of permafrost temperature change per decade, for all boreholes.

About the Data

Indicator Notes

Some borehole sites used in this indicator rely on data collected at depths less than 65 feet, which may be influenced by seasonal or short-term surface temperature change. Additionally, some sites were not measured every year, creating gaps of two to four years, but all the sites included in this indicator meet minimum data completeness required for long-term change calculation. Logistical issues caused minor fluctuation in the exact timing of when measurements were collected each year, which could also add some uncertainty to the results.

This collection of sites is not necessarily representative of all types of permafrost or all temperature trends throughout Alaska. Permafrost temperature can vary depending on local environmental factors such as soil type, vegetation characteristics, and snow cover depth. Notably, permafrost in northern Alaska is naturally colder and more continuous than permafrost in the interior region.

Data Sources

The data in this indicator are based on seasonal measurements collected by researchers and provided by Dr. Vladimir Romanovsky of the Permafrost Laboratory of the University of Alaska Fairbanks. Borehole temperature data are made publicly available along with corresponding metadata at: https://permafrost.gi.alaska.edu/sites_map. This data set has been used and published as part of peer-reviewed journal articles on observed changes in regional and global permafrost.

Native names for borehole sites were identified at: www.uaf.edu/anla/collections/map/names and: https://gis.data.alaska.gov/datasets/DCCED::alaska-native-place-names-1/about.

Technical Documentation

References

  1. IPCC (Intergovernmental Panel on Climate Change). (2019). Summary for policymakers. In The ocean and cryosphere in a changing climate: Special report of the Intergovernmental Panel on Climate Change. Cambridge University Press. https://doi.org/10.1017/9781009157964.001
  2. Osterkamp, T. E., & Jorgenson, M. T. (2009). Permafrost conditions and processes. In R. Young & L. Norby, Geological Monitoring. Geological Society of America. https://doi.org/10.1130/2009.monitoring(09)
  3. AMAP (Arctic Monitoring and Assessment Programme). (2017). Snow, water, ice and permafrost in the Arctic (SWIPA) 2017. www.amap.no/documents/doc/snow-water-ice-and-permafrost-in-the-arctic-swipa-2017/1610
  4. Huntington, H. P., Strawhacker, C., Falke, J., Ward, E. M., Behnken, L., Curry, T. N., Herrmann, A. C., Itchuaqiyaq, C. U., Littell, J. S., Logerwell, E. A., Meeker, D., Overbeck, J. R., Peter, D. L., Pincus, R., Quintyne, A. A., Trainor, S. F., & Yoder, S. A. (2023). Chapter 29: Alaska. In USGCRP (U.S. Global Change Research Program), Fifth National Climate Assessment. https://doi.org/10.7930/NCA5.2023.CH29
  5. University of Alaska Fairbanks. (2024). Sites map. Retrieved December 11, 2024, from https://permafrost.gi.alaska.edu/sites_map

Text on this page is EPA’s own published wording (a U.S. Government work, not subject to domestic copyright), extracted from EPA’s published indicator page and verified paragraph by paragraph against the archived HTML. Data, chart code, and the full extraction pipeline are maintained in the permafrost repository, which this page reads its data from directly.

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