Permafrost

The properties of frozen ground react sensitively to climate and environmental changes in high-latitude and high-altitude regions. This includes the temperature distribution in the permafrost layer and the depth of the overlying active layer where seasonal freezing and thawing occur. Changes in these quantities have important impacts on terrain stability, coastal erosion, surface and subsurface water, the carbon cycle and vegetation development.

Permafrost Temperature Evolution

Figure: Permafrost temperature evolution at 20 m depth at selected borehole sites: Left: Permafrost sites in Norway and the European Alps. Right: Permafrost temperature along the Qinghai-Xizang Highway on the Tibetan Plateau.

Source: BAMS report 2019 (in prep.)


ECV Products and Requirements

These products and requirements reflect the Implementation Plan 2022 (GCOS-244).

The requirements are found in the complete 2022 ECVs Requirements document as well: ECV Permafrost.

Products°CPermafrost Temperature (PT)
 (*)UnitValues
Horizontal ResolutionGN/A (Spatial distribution of boreholes)Regular spacing
BTransects / various settings
TCharacterization of bioclimate zones
Vertical Resolution: Borehole depthG Deeper than ZAA
BDown to ZAA
TBelow permafrost table
Vertical Resolution: Sensor spacing  along borehole for continuous monitoringGmAbove ZAA: 0.2
B 
TAbove ZAA: 0.5
Vertical Resolution: measuring interval for manual measurementGmBelow ZAA: 5 to 10
B 
TBelow ZAA: >10
Temporal ResolutionG Active layer: 1h; Down to ZAA: 1d; Below ZAA: 1 month
BActive layer: 1d; Down to ZAA: 1 month; Below ZAA: 1 year
TActive layer: 1 month; Down to ZAA: 1 year; Below ZAA: 5 years
TimelinessG Weekly /real time
 B 1 year
 T 5 years
Required Measurement UncertaintyG°C0.01
 B 0.1
 T 0.2
StabilityG°C0.01
 B 0.05
 T 0.1
ProductscmActive Layer Thickness (ALT) m y-1Rock Glacier Velocity (RGV)
Spatial distribution of selected rock glaciersSpatial resolution of the measurem ent. 1 value per selected rock glacier unit
 (*)UnitValues UnitValuesValues
Horizontal ResolutionGmRegular spacing  Regional coverageFlow field
BTransects Multiple sites in a defined regional contextFew discrete points
Tsufficient sites to characterize each bioclimatic subzone Isolated siteVelocity value at a point
Vertical ResolutionGcm2   
B10  
T20  
Temporal ResolutionGy1 (at end of thawing period) y (Frequency and Observation time window)1 and 1
B  1 and <1
T1 (at end of thawing period) 2-5 and >1
TimelinessGy1 month3
B   
T1 12
Required Measurement Uncertainty (2-sigma)Gcm1/5 %5
B  10
T2/15 20
StabilityGcm1 ywith overlap several years
B5 with overlap 1 year
T10 without overlap

(*) Goal (G): an ideal requirement above which further improvements are not necessary. Breakthrough (B): an intermediate level between threshold and goal which, if achieved, would result in a significant improvement for the targeted application. The breakthrough value may also indicate the level at which specified uses within climate monitoring become possible. It may be appropriate to have different breakthrough values for different uses. Threshold (T): the minimum requirement to be met to ensure that data are useful.

Data sources

This list provides sources for openly accessible data sets with worldwide coverage for which metadata is available. It is curated by the respective GCOS ECV Steward(s). The list does not claim to be complete. Anyone with a suitable dataset who wishes it to be added to this list should contact the abombelliatwmo [dot] int (GCOS Secretariat).

  • Global Terrestrial Network for Permafrost (GTN-P) Database
Permafrost
Домен:
Land
Subdomain:
Cryosphere
Scientific Area:
Snow and Ice
ECV Steward:
Philippe Schoeneich
Products:
Permafrost Temperature (PT); Active Layer Thickness (ALT); Rock Glacier Velocity (RGV)