Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis
The effects of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The null-space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consi...
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ftcopernicus:oai:publications.copernicus.org:tc30352 2023-05-15T13:03:23+02:00 Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis Harp, D. R. Atchley, A. L. Painter, S. L. Coon, E. T. Wilson, C. J. Romanovsky, V. E. Rowland, J. C. 2018-09-27 application/pdf https://doi.org/10.5194/tc-10-341-2016 https://tc.copernicus.org/articles/10/341/2016/ eng eng doi:10.5194/tc-10-341-2016 https://tc.copernicus.org/articles/10/341/2016/ eISSN: 1994-0424 Text 2018 ftcopernicus https://doi.org/10.5194/tc-10-341-2016 2020-07-20T16:24:16Z The effects of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The null-space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21st century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows for the evaluation of predictive uncertainty (due to soil property (parametric) uncertainty) and the inter-annual climate variability due to year to year differences in CESM climate forcings. After calibrating to measured borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant predictive uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Inter-annual climate variability in projected soil moisture content and Stefan number are small. A volume- and time-integrated Stefan number decreases significantly, indicating a shift in subsurface energy utilization in the future climate (latent heat of phase change becomes more important than heat conduction). Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we quantify the relative magnitude of soil property uncertainty to another source of permafrost uncertainty, structural climate model uncertainty. We show that the effect of calibration-constrained uncertainty in soil properties, although significant, is less than that produced by structural climate model uncertainty for this location. Text Active layer thickness permafrost Copernicus Publications: E-Journals The Cryosphere 10 1 341 358 |
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Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
The effects of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The null-space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21st century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows for the evaluation of predictive uncertainty (due to soil property (parametric) uncertainty) and the inter-annual climate variability due to year to year differences in CESM climate forcings. After calibrating to measured borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant predictive uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Inter-annual climate variability in projected soil moisture content and Stefan number are small. A volume- and time-integrated Stefan number decreases significantly, indicating a shift in subsurface energy utilization in the future climate (latent heat of phase change becomes more important than heat conduction). Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we quantify the relative magnitude of soil property uncertainty to another source of permafrost uncertainty, structural climate model uncertainty. We show that the effect of calibration-constrained uncertainty in soil properties, although significant, is less than that produced by structural climate model uncertainty for this location. |
format |
Text |
author |
Harp, D. R. Atchley, A. L. Painter, S. L. Coon, E. T. Wilson, C. J. Romanovsky, V. E. Rowland, J. C. |
spellingShingle |
Harp, D. R. Atchley, A. L. Painter, S. L. Coon, E. T. Wilson, C. J. Romanovsky, V. E. Rowland, J. C. Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis |
author_facet |
Harp, D. R. Atchley, A. L. Painter, S. L. Coon, E. T. Wilson, C. J. Romanovsky, V. E. Rowland, J. C. |
author_sort |
Harp, D. R. |
title |
Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis |
title_short |
Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis |
title_full |
Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis |
title_fullStr |
Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis |
title_full_unstemmed |
Effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis |
title_sort |
effect of soil property uncertainties on permafrost thaw projections: a calibration-constrained analysis |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-10-341-2016 https://tc.copernicus.org/articles/10/341/2016/ |
genre |
Active layer thickness permafrost |
genre_facet |
Active layer thickness permafrost |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-10-341-2016 https://tc.copernicus.org/articles/10/341/2016/ |
op_doi |
https://doi.org/10.5194/tc-10-341-2016 |
container_title |
The Cryosphere |
container_volume |
10 |
container_issue |
1 |
container_start_page |
341 |
op_container_end_page |
358 |
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1766335627558649856 |