RT Journal Article
T1 Increasing the Depth of a Land Surface Model. Part II: Temperature Sensitivity to Improved Subsurface Thermodynamics and Associated Permafrost Response
A1 Steinert, N. J.
A1 González Rouco, Jesús Fidel
A1 De Vrese, P.
A1 García Bustamante, Elena
A1 Hagemann, S.
A1 Melo Aguilar, C.
A1 Jungclaus, J. H.
A1 Lorenz, S. J.
AB The impact of various modifications of the JSBACH land surface model to represent soil temperature and cold-region hydro-thermodynamic processes in climate projections of the twenty-first century is examined. We explore the sensitivity of JSBACH to changes in the soil thermodynamics, energy balance and storage, and the effect of including freezing and thawing processes. The changes involve 1) the net effect of an improved soil physical representation and 2) the sensitivity of our results to changed soil parameter values and their contribution to the simulation of soil temperatures and soil moisture, both aspects being presented in the frame of an increased bottom boundary depth from 9.83 to 1418.84 m. The implementation of water phase changes and supercooled water in the ground creates a coupling between the soil thermal and hydrological regimes through latent heat exchange. Momentous effects on subsurface temperature of up to +/- 3 K, together with soil drying in the high northern latitudes, can be found at regional scales when applying improved hydro-thermodynamic soil physics. The sensitivity of the model to different soil parameter datasets is relatively low but shows important implications for the root zone soil moisture content. The evolution of permafrost under preindustrial forcing conditions emerges in simulated trajectories of stable states that differ by 4-6 x 10(6) km(2) and shows large differences in the spatial extent of 10(5)-10(6) km(2) by 2100, depending on the model configuration.
PB American Meteorological Society
SN 1525-755X
YR 2021
FD 2021-12
LK https://hdl.handle.net/20.500.14352/4957
UL https://hdl.handle.net/20.500.14352/4957
LA eng
NO © 2021 American Meteorological Society. We gratefully acknowledge the IlModelS (CGL2014-59644-R) and GreatModelS (RTI2018-102355505B-C21 and RTI2018-102305-A-C22) projects. Stefan Hagemann contributed in the frame of the ERANET-plus-Russia project SODEEP (Study Of the Development of Extreme Events over Permafrost areas) supported by BMBF (Grant 01DJ18016A). This work used resources of the Deutsches Klimarechenzentrum (DKRZ) granted by its Scientific Steering Committee (WLA) under project ID bm1026. We also wish to thank Veronika Gayler for technical support on JSBACH.
NO Ministerio de Economía y Competitividad (MINECO)
NO BMBF Federal Ministry of Education & Research
NO Scientific Steering Committee (WLA)
DS Docta Complutense
RD 22 abr 2025