title: Modelling the Thermal Dynamics of Polygonal Soil  Structures in the Permafrost of the Lena Delta,  Northern Siberia
creator: Heikenfeld, Max
subject: ddc-500
subject: 500 Natural sciences and mathematics
subject: ddc-530
subject: 530 Physics
subject: ddc-550
subject: 550 Earth sciences
description: Patterned ground structures characterised by strong heterogeneities in surface and subsur-  face properties are a common feature of permafrost landscapes in the Arctic. In this thesis,  an existing permafrost model including conductive heat transfer and the phase change of  water is extended to simulate the thermal dynamics of polygonal soil structures in an Arctic  tundra wetland in Northern Siberia. A two-dimensional model formulation in cylindrical  coordinates is implemented and coupled to a surface energy balance model. The model  performance is assessed by a comparison with analytical solutions and field measurements  of soil temperature and surface heat fluxes. The heat transfer in the soil is represented  well with mean absolute deviations of up to 1 ◦ C. The coupled simulations with surface  energy balance calculation represent the soil temperatures with larger deviations that can  be attributed to the description of the snow cover in the model. Lateral heat fluxes in the  polygon only occur during limited periods and do not have a substantial impact on the  thermal dynamics of the system. Simplified one-dimensional model descriptions based on  averaged soil and surface parameters show a cold bias of up to 0.7 ◦ C in the mean annual  temperature of the permafrost compared with the detailed two-dimensional model. The  thaw depth is simulated consistently by the models of different complexity .
date: 2013
type: Master's thesis
type: info:eu-repo/semantics/masterThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/15966/1/MA_Max_Heikenfeld.pdf
identifier: DOI:10.11588/heidok.00015966
identifier: urn:nbn:de:bsz:16-heidok-159662
identifier:   Heikenfeld, Max  (2013) Modelling the Thermal Dynamics of Polygonal Soil Structures in the Permafrost of the Lena Delta, Northern Siberia.  [Master's thesis]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/15966/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng