Identification

Title

Effects of excess ground ice on projections of permafrost in a warming climate

Abstract

In permafrost soils, 'excess ice', also referred to as ground ice, exists in amounts exceeding soil porosity in forms such as ice lenses and wedges. Here, we incorporate a simple representation of excess ice in the Community Land Model (CLM4.5) to investigate how excess ice affects projected permafrost thaw and associated hydrologic responses. We initialize spatially explicit excess ice obtained from the Circum-Arctic Map of Permafrost and Ground-Ice Conditions. The excess ice in the model acts to slightly reduce projected soil warming by about 0.35 °C by 2100 in a high greenhouse gas emissions scenario. The presence of excess ice slows permafrost thaw at a given location with about a 10 year delay in permafrost thaw at 3 m depth at most high excess ice locations. The soil moisture response to excess ice melt is transient and depends largely on the timing of thaw with wetter/saturated soil moisture conditions persisting slightly longer due to delayed post-thaw drainage. Based on the model projections of excess ice melt, we can estimate spatially explicit gridcell mean surface subsidence with values ranging up to 0.5 m by 2100 depending on the initial excess ice content and the extent of melt.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7qz2bzr

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2014-12-08T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact