Articles | Volume 10, issue 5
The Cryosphere, 10, 2291–2315, 2016
https://doi.org/10.5194/tc-10-2291-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue: Changing Permafrost in the Arctic and its Global Effects in...
Research article
30 Sep 2016
Research article
| 30 Sep 2016
Effects of bryophyte and lichen cover on permafrost soil temperature at large scale
Philipp Porada et al.
Related authors
Suman Halder, Susanne K. M. Arens, Kai Jensen, Tais W. Dahl, and Philipp Porada
Geosci. Model Dev., 15, 2325–2343, https://doi.org/10.5194/gmd-15-2325-2022, https://doi.org/10.5194/gmd-15-2325-2022, 2022
Short summary
Short summary
A dynamic vegetation model, designed to estimate potential impacts of early vascular vegetation, namely, lycopsids, on the biogeochemical cycle at a local scale. Lycopsid Model (LYCOm) estimates the productivity and physiological properties of lycopsids across a broad climatic range along with natural selection, which is then utilized to adjudge their weathering potential. It lays the foundation for estimation of their impacts during their long evolutionary history starting from the Ordovician.
Félix Pellerin, Philipp Porada, and Inga Hense
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2020-55, https://doi.org/10.5194/esd-2020-55, 2020
Revised manuscript not accepted
Short summary
Short summary
While several biological processes are similar among terrestrial and marine ecosystems, their representation in Earth System Models may differ. By comparing the terrestrial and marine modules of 17 Earth System Models, we found multiple evidences of unjustified differences in processes representation. These inconsistencies may lead to wrong predictions about the role of biosphere in the climate system and skew our perception of the relative influence of each ecosystem on climate.
Philipp Porada, Alexandra Tamm, Jose Raggio, Yafang Cheng, Axel Kleidon, Ulrich Pöschl, and Bettina Weber
Biogeosciences, 16, 2003–2031, https://doi.org/10.5194/bg-16-2003-2019, https://doi.org/10.5194/bg-16-2003-2019, 2019
Short summary
Short summary
The trace gases NO and HONO are crucial for atmospheric chemistry. It has been suggested that biological soil crusts in drylands contribute substantially to global NO and HONO emissions, based on empirical upscaling of laboratory and field observations. Here we apply an alternative, process-based modeling approach to predict these emissions. We find that biological soil crusts emit globally significant amounts of NO and HONO, which also vary depending on the type of biological soil crust.
Stefano Manzoni, Petr Čapek, Philipp Porada, Martin Thurner, Mattias Winterdahl, Christian Beer, Volker Brüchert, Jan Frouz, Anke M. Herrmann, Björn D. Lindahl, Steve W. Lyon, Hana Šantrůčková, Giulia Vico, and Danielle Way
Biogeosciences, 15, 5929–5949, https://doi.org/10.5194/bg-15-5929-2018, https://doi.org/10.5194/bg-15-5929-2018, 2018
Short summary
Short summary
Carbon fixed by plants and phytoplankton through photosynthesis is ultimately stored in soils and sediments or released to the atmosphere during decomposition of dead biomass. Carbon-use efficiency is a useful metric to quantify the fate of carbon – higher efficiency means higher storage and lower release to the atmosphere. Here we summarize many definitions of carbon-use efficiency and study how this metric changes from organisms to ecosystems and from terrestrial to aquatic environments.
Christian Beer, Philipp Porada, Altug Ekici, and Matthias Brakebusch
The Cryosphere, 12, 741–757, https://doi.org/10.5194/tc-12-741-2018, https://doi.org/10.5194/tc-12-741-2018, 2018
Short summary
Short summary
Idealized model experiments demonstrate that, in addition to a gradual climate change, changing daily to weekly variability of meteorological variables and extreme events will also have an impact on mean annual ground temperature in high-latitude permafrost areas. In fact, results of the land surface model experiments show that the projected increase of variability of meteorological variables leads to cooler permafrost soil in contrast to an otherwise soil warming in response to climate change.
Sarah E. Chadburn, Gerhard Krinner, Philipp Porada, Annett Bartsch, Christian Beer, Luca Belelli Marchesini, Julia Boike, Altug Ekici, Bo Elberling, Thomas Friborg, Gustaf Hugelius, Margareta Johansson, Peter Kuhry, Lars Kutzbach, Moritz Langer, Magnus Lund, Frans-Jan W. Parmentier, Shushi Peng, Ko Van Huissteden, Tao Wang, Sebastian Westermann, Dan Zhu, and Eleanor J. Burke
Biogeosciences, 14, 5143–5169, https://doi.org/10.5194/bg-14-5143-2017, https://doi.org/10.5194/bg-14-5143-2017, 2017
Short summary
Short summary
Earth system models (ESMs) are our main tools for understanding future climate. The Arctic is important for the future carbon cycle, particularly due to the large carbon stocks in permafrost. We evaluated the performance of the land component of three major ESMs at Arctic tundra sites, focusing on the fluxes and stocks of carbon.
We show that the next steps for model improvement are to better represent vegetation dynamics, to include mosses and to improve below-ground carbon cycle processes.
Philipp Porada, Ulrich Pöschl, Axel Kleidon, Christian Beer, and Bettina Weber
Biogeosciences, 14, 1593–1602, https://doi.org/10.5194/bg-14-1593-2017, https://doi.org/10.5194/bg-14-1593-2017, 2017
Short summary
Short summary
Lichens and bryophytes have been shown to release nitrous oxide, which is a strong greenhouse gas and atmospheric ozone-depleting agent. Here we apply a process-based computer model of lichens and bryophytes at the global scale, to estimate growth and respiration of the organisms. By relating respiration to nitrous oxide release, we simulate global nitrous oxide emissions of 0.27 (0.19–0.35) Tg yr−1. Moreover, we quantify different sources of uncertainty in nitrous oxide emission rates.
Christian Beer, Philipp Porada, Altug Ekici, and Matthias Brakebusch
The Cryosphere Discuss., https://doi.org/10.5194/tc-2016-210, https://doi.org/10.5194/tc-2016-210, 2016
Preprint withdrawn
Short summary
Short summary
Models suggest thawing permafrost in future due to climate change. In addition to warming, day-to-day variability of air temperature and precipitation is projected to increase. In an idealized theoretical model experiment we show that such changing short-term variability will reduce soil warming as a consequence of air warming by up to 1 K due to effects on snow and moss insulating layers. This shows the need of a mechanistic representation of such layers in Earth system models.
C. Buendía, S. Arens, T. Hickler, S. I. Higgins, P. Porada, and A. Kleidon
Biogeosciences, 11, 3661–3683, https://doi.org/10.5194/bg-11-3661-2014, https://doi.org/10.5194/bg-11-3661-2014, 2014
A. Kleidon, M. Renner, and P. Porada
Hydrol. Earth Syst. Sci., 18, 2201–2218, https://doi.org/10.5194/hess-18-2201-2014, https://doi.org/10.5194/hess-18-2201-2014, 2014
P. Porada, B. Weber, W. Elbert, U. Pöschl, and A. Kleidon
Biogeosciences, 10, 6989–7033, https://doi.org/10.5194/bg-10-6989-2013, https://doi.org/10.5194/bg-10-6989-2013, 2013
Suman Halder, Susanne K. M. Arens, Kai Jensen, Tais W. Dahl, and Philipp Porada
Geosci. Model Dev., 15, 2325–2343, https://doi.org/10.5194/gmd-15-2325-2022, https://doi.org/10.5194/gmd-15-2325-2022, 2022
Short summary
Short summary
A dynamic vegetation model, designed to estimate potential impacts of early vascular vegetation, namely, lycopsids, on the biogeochemical cycle at a local scale. Lycopsid Model (LYCOm) estimates the productivity and physiological properties of lycopsids across a broad climatic range along with natural selection, which is then utilized to adjudge their weathering potential. It lays the foundation for estimation of their impacts during their long evolutionary history starting from the Ordovician.
Félix Pellerin, Philipp Porada, and Inga Hense
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2020-55, https://doi.org/10.5194/esd-2020-55, 2020
Revised manuscript not accepted
Short summary
Short summary
While several biological processes are similar among terrestrial and marine ecosystems, their representation in Earth System Models may differ. By comparing the terrestrial and marine modules of 17 Earth System Models, we found multiple evidences of unjustified differences in processes representation. These inconsistencies may lead to wrong predictions about the role of biosphere in the climate system and skew our perception of the relative influence of each ecosystem on climate.
Altug Ekici, Hanna Lee, David M. Lawrence, Sean C. Swenson, and Catherine Prigent
Geosci. Model Dev., 12, 5291–5300, https://doi.org/10.5194/gmd-12-5291-2019, https://doi.org/10.5194/gmd-12-5291-2019, 2019
Short summary
Short summary
Ice-rich permafrost thaw can create expanding thermokarst lakes as well as shrinking large wetlands. Such processes can have major biogeochemical implications and feedbacks to climate systems by altering the pathways and rates of permafrost carbon release. We developed a new model parameterization that allows a direct representation of surface water dynamics with subsidence. Our results show increased surface water fractions around western Siberian plains and northeastern territories of Canada.
Philipp Porada, Alexandra Tamm, Jose Raggio, Yafang Cheng, Axel Kleidon, Ulrich Pöschl, and Bettina Weber
Biogeosciences, 16, 2003–2031, https://doi.org/10.5194/bg-16-2003-2019, https://doi.org/10.5194/bg-16-2003-2019, 2019
Short summary
Short summary
The trace gases NO and HONO are crucial for atmospheric chemistry. It has been suggested that biological soil crusts in drylands contribute substantially to global NO and HONO emissions, based on empirical upscaling of laboratory and field observations. Here we apply an alternative, process-based modeling approach to predict these emissions. We find that biological soil crusts emit globally significant amounts of NO and HONO, which also vary depending on the type of biological soil crust.
Thomas Schneider von Deimling, Thomas Kleinen, Gustaf Hugelius, Christian Knoblauch, Christian Beer, and Victor Brovkin
Clim. Past, 14, 2011–2036, https://doi.org/10.5194/cp-14-2011-2018, https://doi.org/10.5194/cp-14-2011-2018, 2018
Short summary
Short summary
Past cold ice age temperatures and the subsequent warming towards the Holocene had large consequences for soil organic carbon (SOC) stored in perennially frozen grounds. Using an Earth system model we show how the spread in areas affected by permafrost have changed under deglacial warming, along with changes in SOC accumulation. Our model simulations suggest phases of circum-Arctic permafrost SOC gain and losses, with a net increase in SOC between the last glacial maximum and the pre-industrial.
Stefano Manzoni, Petr Čapek, Philipp Porada, Martin Thurner, Mattias Winterdahl, Christian Beer, Volker Brüchert, Jan Frouz, Anke M. Herrmann, Björn D. Lindahl, Steve W. Lyon, Hana Šantrůčková, Giulia Vico, and Danielle Way
Biogeosciences, 15, 5929–5949, https://doi.org/10.5194/bg-15-5929-2018, https://doi.org/10.5194/bg-15-5929-2018, 2018
Short summary
Short summary
Carbon fixed by plants and phytoplankton through photosynthesis is ultimately stored in soils and sediments or released to the atmosphere during decomposition of dead biomass. Carbon-use efficiency is a useful metric to quantify the fate of carbon – higher efficiency means higher storage and lower release to the atmosphere. Here we summarize many definitions of carbon-use efficiency and study how this metric changes from organisms to ecosystems and from terrestrial to aquatic environments.
Karel Castro-Morales, Thomas Kleinen, Sonja Kaiser, Sönke Zaehle, Fanny Kittler, Min Jung Kwon, Christian Beer, and Mathias Göckede
Biogeosciences, 15, 2691–2722, https://doi.org/10.5194/bg-15-2691-2018, https://doi.org/10.5194/bg-15-2691-2018, 2018
Short summary
Short summary
We present year-round methane emissions from wetlands in Northeast Siberia that were simulated with a land surface model. Ground-based flux measurements from the same area were used for evaluation of the model results, finding a best agreement with the observations in the summertime emissions that take place in this region predominantly through plants. During winter, methane emissions through the snow contribute 4 % of the total annual methane budget, but these are still underestimated.
Christian Beer, Philipp Porada, Altug Ekici, and Matthias Brakebusch
The Cryosphere, 12, 741–757, https://doi.org/10.5194/tc-12-741-2018, https://doi.org/10.5194/tc-12-741-2018, 2018
Short summary
Short summary
Idealized model experiments demonstrate that, in addition to a gradual climate change, changing daily to weekly variability of meteorological variables and extreme events will also have an impact on mean annual ground temperature in high-latitude permafrost areas. In fact, results of the land surface model experiments show that the projected increase of variability of meteorological variables leads to cooler permafrost soil in contrast to an otherwise soil warming in response to climate change.
Sarah E. Chadburn, Gerhard Krinner, Philipp Porada, Annett Bartsch, Christian Beer, Luca Belelli Marchesini, Julia Boike, Altug Ekici, Bo Elberling, Thomas Friborg, Gustaf Hugelius, Margareta Johansson, Peter Kuhry, Lars Kutzbach, Moritz Langer, Magnus Lund, Frans-Jan W. Parmentier, Shushi Peng, Ko Van Huissteden, Tao Wang, Sebastian Westermann, Dan Zhu, and Eleanor J. Burke
Biogeosciences, 14, 5143–5169, https://doi.org/10.5194/bg-14-5143-2017, https://doi.org/10.5194/bg-14-5143-2017, 2017
Short summary
Short summary
Earth system models (ESMs) are our main tools for understanding future climate. The Arctic is important for the future carbon cycle, particularly due to the large carbon stocks in permafrost. We evaluated the performance of the land component of three major ESMs at Arctic tundra sites, focusing on the fluxes and stocks of carbon.
We show that the next steps for model improvement are to better represent vegetation dynamics, to include mosses and to improve below-ground carbon cycle processes.
Eleanor J. Burke, Altug Ekici, Ye Huang, Sarah E. Chadburn, Chris Huntingford, Philippe Ciais, Pierre Friedlingstein, Shushi Peng, and Gerhard Krinner
Biogeosciences, 14, 3051–3066, https://doi.org/10.5194/bg-14-3051-2017, https://doi.org/10.5194/bg-14-3051-2017, 2017
Short summary
Short summary
There are large reserves of carbon within the permafrost which might be released to the atmosphere under global warming. Our models suggest this release may cause an additional global temperature increase of 0.005 to 0.2°C by the year 2100 and 0.01 to 0.34°C by the year 2300. Under climate mitigation scenarios this is between 1.5 and 9 % (by 2100) and between 6 and 16 % (by 2300) of the global mean temperature change. There is a large uncertainty associated with these results.
Philipp Porada, Ulrich Pöschl, Axel Kleidon, Christian Beer, and Bettina Weber
Biogeosciences, 14, 1593–1602, https://doi.org/10.5194/bg-14-1593-2017, https://doi.org/10.5194/bg-14-1593-2017, 2017
Short summary
Short summary
Lichens and bryophytes have been shown to release nitrous oxide, which is a strong greenhouse gas and atmospheric ozone-depleting agent. Here we apply a process-based computer model of lichens and bryophytes at the global scale, to estimate growth and respiration of the organisms. By relating respiration to nitrous oxide release, we simulate global nitrous oxide emissions of 0.27 (0.19–0.35) Tg yr−1. Moreover, we quantify different sources of uncertainty in nitrous oxide emission rates.
Eleanor J. Burke, Sarah E. Chadburn, and Altug Ekici
Geosci. Model Dev., 10, 959–975, https://doi.org/10.5194/gmd-10-959-2017, https://doi.org/10.5194/gmd-10-959-2017, 2017
Short summary
Short summary
There is a large amount of relatively inert organic carbon locked into permafrost soils. In a warming climate the permafrost will thaw and this organic carbon will become vulnerable to decomposition. This process is not typically included within Earth system models (ESMs). This paper describes the development of a vertically resolved soil organic carbon decomposition model which, in the future, can be included within the UKESM to quantify the response of the climate to permafrost carbon loss.
Sonja Kaiser, Mathias Göckede, Karel Castro-Morales, Christian Knoblauch, Altug Ekici, Thomas Kleinen, Sebastian Zubrzycki, Torsten Sachs, Christian Wille, and Christian Beer
Geosci. Model Dev., 10, 333–358, https://doi.org/10.5194/gmd-10-333-2017, https://doi.org/10.5194/gmd-10-333-2017, 2017
Short summary
Short summary
A new consistent, process-based methane module that is integrated with permafrost processes is presented. It was developed within a global land surface scheme and evaluated at a polygonal tundra site in Samoylov, Russia. The calculated methane emissions show fair agreement with field data and capture detailed differences between the explicitly modelled gas transport processes and in the gas dynamics under varying soil water and temperature conditions during seasons and on different microsites.
Christian Beer, Philipp Porada, Altug Ekici, and Matthias Brakebusch
The Cryosphere Discuss., https://doi.org/10.5194/tc-2016-210, https://doi.org/10.5194/tc-2016-210, 2016
Preprint withdrawn
Short summary
Short summary
Models suggest thawing permafrost in future due to climate change. In addition to warming, day-to-day variability of air temperature and precipitation is projected to increase. In an idealized theoretical model experiment we show that such changing short-term variability will reduce soil warming as a consequence of air warming by up to 1 K due to effects on snow and moss insulating layers. This shows the need of a mechanistic representation of such layers in Earth system models.
Stefan Hagemann, Tanja Blome, Altug Ekici, and Christian Beer
Earth Syst. Dynam., 7, 611–625, https://doi.org/10.5194/esd-7-611-2016, https://doi.org/10.5194/esd-7-611-2016, 2016
Short summary
Short summary
The present study analyses how cold-region physical soil processes, especially freezing of soil water, impact large-scale hydrology and climate over Northern Hemisphere high-latitude land areas. For this analysis, an atmosphere–land global climate model was used. It is shown that including these processes in the model leads to improved discharge in spring and a positive land–atmosphere feedback to precipitation over the high latitudes that has previously not been noted for the high latitudes.
A. Ekici, S. Chadburn, N. Chaudhary, L. H. Hajdu, A. Marmy, S. Peng, J. Boike, E. Burke, A. D. Friend, C. Hauck, G. Krinner, M. Langer, P. A. Miller, and C. Beer
The Cryosphere, 9, 1343–1361, https://doi.org/10.5194/tc-9-1343-2015, https://doi.org/10.5194/tc-9-1343-2015, 2015
Short summary
Short summary
This paper compares the performance of different land models in estimating soil thermal regimes at distinct cold region landscape types. Comparing models with different processes reveal the importance of surface insulation (snow/moss layer) and soil internal processes (heat/water transfer). The importance of model processes also depend on site conditions such as high/low snow cover, dry/wet soil types.
C. Buendía, S. Arens, T. Hickler, S. I. Higgins, P. Porada, and A. Kleidon
Biogeosciences, 11, 3661–3683, https://doi.org/10.5194/bg-11-3661-2014, https://doi.org/10.5194/bg-11-3661-2014, 2014
A. Kleidon, M. Renner, and P. Porada
Hydrol. Earth Syst. Sci., 18, 2201–2218, https://doi.org/10.5194/hess-18-2201-2014, https://doi.org/10.5194/hess-18-2201-2014, 2014
A. Ekici, C. Beer, S. Hagemann, J. Boike, M. Langer, and C. Hauck
Geosci. Model Dev., 7, 631–647, https://doi.org/10.5194/gmd-7-631-2014, https://doi.org/10.5194/gmd-7-631-2014, 2014
P. Porada, B. Weber, W. Elbert, U. Pöschl, and A. Kleidon
Biogeosciences, 10, 6989–7033, https://doi.org/10.5194/bg-10-6989-2013, https://doi.org/10.5194/bg-10-6989-2013, 2013
Related subject area
Numerical Modelling
Can changes in deformation regimes be inferred from crystallographic preferred orientations in polar ice?
Stabilizing effect of mélange buttressing on the marine ice-cliff instability of the West Antarctic Ice Sheet
A probabilistic seabed–ice keel interaction model
Modelling supraglacial debris-cover evolution from the single-glacier to the regional scale: an application to High Mountain Asia
The effect of changing sea ice on wave climate trends along Alaska's central Beaufort Sea coast
Strong increase in thawing of subsea permafrost in the 22nd century caused by anthropogenic climate change
Arctic sea ice anomalies during the MOSAiC winter 2019/20
Effective coefficient of diffusion and permeability of firn at Dome C and Lock In, Antarctica, and of various snow types – estimates over the 100–850 kg m−3 density range
Elements of future snowpack modeling – Part 1: A physical instability arising from the nonlinear coupling of transport and phase changes
The instantaneous impact of calving and thinning on the Larsen C Ice Shelf
Derivation of bedrock topography measurement requirements for the reduction of uncertainty in ice-sheet model projections of Thwaites Glacier
A comparison of the stability and performance of depth-integrated ice-dynamics solvers
Impact of runoff temporal distribution on ice dynamics
A new vertically integrated MOno-Layer Higher-Order (MOLHO) ice flow model
On the contribution of grain boundary sliding type creep to firn densification – an assessment using an optimization approach
Elements of future snowpack modeling – Part 2: A modular and extendable Eulerian–Lagrangian numerical scheme for coupled transport, phase changes and settling processes
Land-atmosphere interactions in sub-polar and alpine climates in the CORDEX FPS LUCAS models: I. Evaluation of the snow-albedo effect
Assessment of neutrons from secondary cosmic rays at mountain altitudes – Geant4 simulations of environmental parameters including soil moisture and snow cover
A seasonal algorithm of the snow-covered area fraction for mountainous terrain
Sea ice floe size: its impact on pan-Arctic and local ice mass, and required model complexity
Edge displacement scores
The 21st-century fate of the Mocho-Choshuenco ice cap in southern Chile
Lateral thermokarst patterns in permafrost peat plateaus in northern Norway
Modelling steady states and the transient response of debris-covered glaciers
Marine ice sheet experiments with the Community Ice Sheet Model
Twentieth century global glacier mass change: an ensemble-based model reconstruction
A method for solving heat transfer with phase change in ice or soil that allows for large time steps while guaranteeing energy conservation
The transferability of adjoint inversion products between different ice flow models
Inferring the basal sliding coefficient field for the Stokes ice sheet model under rheological uncertainty
The tipping points and early warning indicators for Pine Island Glacier, West Antarctica
Effects of multi-scale heterogeneity on the simulated evolution of ice-rich permafrost lowlands under a warming climate
Sensitivity of ice sheet surface velocity and elevation to variations in basal friction and topography in the full Stokes and shallow-shelf approximation frameworks using adjoint equations
Snow cover duration trends observed at sites and predicted by multiple models
Mapping the age of ice of Gauligletscher combining surface radionuclide contamination and ice flow modeling
Modelling the evolution of Djankuat Glacier, North Caucasus, from 1752 until 2100 CE
Quantifying the effect of ocean bed properties on ice sheet geometry over 40 000 years with a full-Stokes model
Toward a method for downscaling sea ice pressure for navigation purposes
Deep ice layer formation in an alpine snowpack: monitoring and modeling
Brief communication: Time step dependence (and fixes) in Stokes simulations of calving ice shelves
Modelling regional glacier length changes over the last millennium using the Open Global Glacier Model
Evaluating permafrost physics in the Coupled Model Intercomparison Project 6 (CMIP6) models and their sensitivity to climate change
Bayesian calibration of firn densification models
A kinematic formalism for tracking ice–ocean mass exchange on the Earth's surface and estimating sea-level change
The contrasting response of outlet glaciers to interior and ocean forcing
The Arctic Ocean Observation Operator for 6.9 GHz (ARC3O) – Part 1: How to obtain sea ice brightness temperatures at 6.9 GHz from climate model output
The Arctic Ocean Observation Operator for 6.9 GHz (ARC3O) – Part 2: Development and evaluation
Results of the third Marine Ice Sheet Model Intercomparison Project (MISMIP+)
Satellite-retrieved sea ice concentration uncertainty and its effect on modelling wave evolution in marginal ice zones
Ocean-forced evolution of the Amundsen Sea catchment, West Antarctica, by 2100
Multi-physics ensemble snow modelling in the western Himalaya
Maria-Gema Llorens, Albert Griera, Paul D. Bons, Ilka Weikusat, David J. Prior, Enrique Gomez-Rivas, Tamara de Riese, Ivone Jimenez-Munt, Daniel García-Castellanos, and Ricardo A. Lebensohn
The Cryosphere, 16, 2009–2024, https://doi.org/10.5194/tc-16-2009-2022, https://doi.org/10.5194/tc-16-2009-2022, 2022
Short summary
Short summary
Polar ice is formed by ice crystals, which form fabrics that are utilised to interpret how ice sheets flow. It is unclear whether fabrics result from the current flow regime or if they are inherited. To understand the extent to which ice crystals can be reoriented when ice flow conditions change, we simulate and evaluate multi-stage ice flow scenarios according to natural cases. We find that second deformation regimes normally overprint inherited fabrics, with a range of transitional fabrics.
Tanja Schlemm, Johannes Feldmann, Ricarda Winkelmann, and Anders Levermann
The Cryosphere, 16, 1979–1996, https://doi.org/10.5194/tc-16-1979-2022, https://doi.org/10.5194/tc-16-1979-2022, 2022
Short summary
Short summary
Marine cliff instability, if it exists, could dominate Antarctica's contribution to future sea-level rise. It is likely to speed up with ice thickness and thus would accelerate in most parts of Antarctica. Here, we investigate a possible mechanism that might stop cliff instability through cloaking by ice mélange. It is only a first step, but it shows that embayment geometry is, in principle, able to stop marine cliff instability in most parts of West Antarctica.
Frédéric Dupont, Dany Dumont, Jean-François Lemieux, Elie Dumas-Lefebvre, and Alain Caya
The Cryosphere, 16, 1963–1977, https://doi.org/10.5194/tc-16-1963-2022, https://doi.org/10.5194/tc-16-1963-2022, 2022
Short summary
Short summary
In some shallow seas, grounded ice ridges contribute to stabilizing and maintaining a landfast ice cover. A scheme has already proposed where the keel thickness varies linearly with the mean thickness. Here, we extend the approach by taking into account the ice thickness and bathymetry distributions. The probabilistic approach shows a reasonably good agreement with observations and previous grounding scheme while potentially offering more physical insights into the formation of landfast ice.
Loris Compagno, Matthias Huss, Evan Stewart Miles, Michael James McCarthy, Harry Zekollari, Amaury Dehecq, Francesca Pellicciotti, and Daniel Farinotti
The Cryosphere, 16, 1697–1718, https://doi.org/10.5194/tc-16-1697-2022, https://doi.org/10.5194/tc-16-1697-2022, 2022
Short summary
Short summary
We present a new approach for modelling debris area and thickness evolution. We implement the module into a combined mass-balance ice-flow model, and we apply it using different climate scenarios to project the future evolution of all glaciers in High Mountain Asia. We show that glacier geometry, volume, and flow velocity evolve differently when modelling explicitly debris cover compared to glacier evolution without the debris-cover module, demonstrating the importance of accounting for debris.
Kees Nederhoff, Li Erikson, Anita Engelstad, Peter Bieniek, and Jeremy Kasper
The Cryosphere, 16, 1609–1629, https://doi.org/10.5194/tc-16-1609-2022, https://doi.org/10.5194/tc-16-1609-2022, 2022
Short summary
Short summary
Diminishing sea ice is impacting waves across the Arctic region. Recent work shows the effect of the sea ice on offshore waves; however, effects within the nearshore are less known. This study characterizes the wave climate in the central Beaufort Sea coast of Alaska. We show that the reduction of sea ice correlates strongly with increases in the average and extreme waves. However, found trends deviate from offshore, since part of the increase in energy is dissipated before reaching the shore.
Stiig Wilkenskjeld, Frederieke Miesner, Paul P. Overduin, Matteo Puglini, and Victor Brovkin
The Cryosphere, 16, 1057–1069, https://doi.org/10.5194/tc-16-1057-2022, https://doi.org/10.5194/tc-16-1057-2022, 2022
Short summary
Short summary
Thawing permafrost releases carbon to the atmosphere, enhancing global warming. Part of the permafrost soils have been flooded by rising sea levels since the last ice age, becoming subsea permafrost (SSPF). The SSPF is less studied than the part on land. In this study we use a global model to obtain rates of thawing of SSPF under different future climate scenarios until the year 3000. After the year 2100 the scenarios strongly diverge, closely connected to the eventual disappearance of sea ice.
Klaus Dethloff, Wieslaw Maslowski, Stefan Hendricks, Younjoo J. Lee, Helge F. Goessling, Thomas Krumpen, Christian Haas, Dörthe Handorf, Robert Ricker, Vladimir Bessonov, John J. Cassano, Jaclyn Clement Kinney, Robert Osinski, Markus Rex, Annette Rinke, Julia Sokolova, and Anja Sommerfeld
The Cryosphere, 16, 981–1005, https://doi.org/10.5194/tc-16-981-2022, https://doi.org/10.5194/tc-16-981-2022, 2022
Short summary
Short summary
Sea ice thickness anomalies during the MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) winter in January, February and March 2020 were simulated with the coupled Regional Arctic climate System Model (RASM) and compared with CryoSat-2/SMOS satellite data. Hindcast and ensemble simulations indicate that the sea ice anomalies are driven by nonlinear interactions between ice growth processes and wind-driven sea-ice transports, with dynamics playing a dominant role.
Neige Calonne, Alexis Burr, Armelle Philip, Frédéric Flin, and Christian Geindreau
The Cryosphere, 16, 967–980, https://doi.org/10.5194/tc-16-967-2022, https://doi.org/10.5194/tc-16-967-2022, 2022
Short summary
Short summary
Modeling gas transport in ice sheets from surface to close-off is key to interpreting climate archives. Estimates of the diffusion coefficient and permeability of snow and firn are required but remain a large source of uncertainty. We present a new dataset of diffusion coefficients and permeability from 20 to 120 m depth at two Antarctic sites. We suggest predictive formulas to estimate both properties over the entire 100–850 kg m3 density range, i.e., anywhere within the ice sheet column.
Konstantin Schürholt, Julia Kowalski, and Henning Löwe
The Cryosphere, 16, 903–923, https://doi.org/10.5194/tc-16-903-2022, https://doi.org/10.5194/tc-16-903-2022, 2022
Short summary
Short summary
This companion paper deals with numerical particularities of partial differential equations underlying 1D snow models. In this first part we neglect mechanical settling and demonstrate that the nonlinear coupling between diffusive transport (heat and vapor), phase changes and ice mass conservation contains a wave instability that may be relevant for weak layer formation. Numerical requirements are discussed in view of the underlying homogenization scheme.
Tom Mitcham, G. Hilmar Gudmundsson, and Jonathan L. Bamber
The Cryosphere, 16, 883–901, https://doi.org/10.5194/tc-16-883-2022, https://doi.org/10.5194/tc-16-883-2022, 2022
Short summary
Short summary
We modelled the response of the Larsen C Ice Shelf (LCIS) and its tributary glaciers to the calving of the A68 iceberg and validated our results with observations. We found that the impact was limited, confirming that mostly passive ice was calved. Through further calving experiments we quantified the total buttressing provided by the LCIS and found that over 80 % of the buttressing capacity is generated in the first 5 km of the ice shelf downstream of the grounding line.
Blake A. Castleman, Nicole-Jeanne Schlegel, Lambert Caron, Eric Larour, and Ala Khazendar
The Cryosphere, 16, 761–778, https://doi.org/10.5194/tc-16-761-2022, https://doi.org/10.5194/tc-16-761-2022, 2022
Short summary
Short summary
In the described study, we derive an uncertainty range for global mean sea level rise (SLR) contribution from Thwaites Glacier in a 200-year period under an extreme ocean warming scenario. We derive the spatial and vertical resolutions needed for bedrock data acquisition missions in order to limit global mean SLR contribution from Thwaites Glacier to ±2 cm in a 200-year period. We conduct sensitivity experiments in order to present the locations of critical regions in need of accurate mapping.
Alexander Robinson, Daniel Goldberg, and William H. Lipscomb
The Cryosphere, 16, 689–709, https://doi.org/10.5194/tc-16-689-2022, https://doi.org/10.5194/tc-16-689-2022, 2022
Short summary
Short summary
Here we investigate the numerical stability of several commonly used methods in order to determine which of them are capable of resolving the complex physics of the ice flow and are also computationally efficient. We find that the so-called DIVA solver outperforms the others. Its representation of the physics is consistent with more complex methods, while it remains computationally efficient at high resolution.
Basile de Fleurian, Richard Davy, and Petra M. Langebroek
The Cryosphere Discuss., https://doi.org/10.5194/tc-2022-6, https://doi.org/10.5194/tc-2022-6, 2022
Revised manuscript accepted for TC
Short summary
Short summary
As temperature increases more snow and ice melt at the surface of ice sheets. Here we use an ice dynamics and subglacial hydrology model with simplified geometry and climate forcing to study the impact of variations in melt-water on ice dynamics. We focus on the variations in length and intensity of the melt season. Our results show that a longer melt season lead to faster glaciers. However, more intense melt season reduces glaciers seasonal velocities albeit leading to higher peak velocities.
Thiago Dias dos Santos, Mathieu Morlighem, and Douglas Brinkerhoff
The Cryosphere, 16, 179–195, https://doi.org/10.5194/tc-16-179-2022, https://doi.org/10.5194/tc-16-179-2022, 2022
Short summary
Short summary
Projecting the future evolution of Greenland and Antarctica and their potential contribution to sea level rise often relies on computer simulations carried out by numerical ice sheet models. Here we present a new vertically integrated ice sheet model and assess its performance using different benchmarks. The new model shows results comparable to a three-dimensional model at relatively lower computational cost, suggesting that it is an excellent alternative for long-term simulations.
Timm Schultz, Ralf Müller, Dietmar Gross, and Angelika Humbert
The Cryosphere, 16, 143–158, https://doi.org/10.5194/tc-16-143-2022, https://doi.org/10.5194/tc-16-143-2022, 2022
Short summary
Short summary
Firn is the interstage product between snow and ice. Simulations describing the process of firn densification are used in the context of estimating mass changes of the ice sheets and past climate reconstructions. The first stage of firn densification takes place in the upper few meters of the firn column. We investigate how well a material law describing the process of grain boundary sliding works for the numerical simulation of firn densification in this stage.
Anna Simson, Henning Löwe, and Julia Kowalski
The Cryosphere, 15, 5423–5445, https://doi.org/10.5194/tc-15-5423-2021, https://doi.org/10.5194/tc-15-5423-2021, 2021
Short summary
Short summary
This companion paper deals with numerical particularities of partial differential equations underlying one-dimensional snow models. In this second part we include mechanical settling and develop a new hybrid (Eulerian–Lagrangian) method for solving the advection-dominated ice mass conservation on a moving mesh alongside Eulerian diffusion (heat and vapor) and phase changes. The scheme facilitates a modular and extendable solver strategy while retaining controls on numerical accuracy.
Anne Sophie Daloz, Clemens Schwingshackl, Priscilla Mooney, Susanna Strada, Diana Rechid, Edouard L. Davin, Eleni Katragkou, Nathalie de Noblet-Ducoudré, Michal Belda, Tomas Halenka, Marcus Breil, Rita M. Cardoso, Peter Hoffmann, Daniela C. A. Lima, Ronny Meier, Pedro M. M. Soares, Giannis Sofiadis, Gustav Strandberg, Merja H. Toelle, and Marianne T. Lund
The Cryosphere Discuss., https://doi.org/10.5194/tc-2021-290, https://doi.org/10.5194/tc-2021-290, 2021
Revised manuscript accepted for TC
Short summary
Short summary
Snow is an important part of our climate as it regulates the temperature of the Earth’s surface. Reciprocally with climate change, rising temperatures are already altering the Earth’s snow. In this context, it is crucial to better understand snow-atmosphere processes and the ability of climate models to represent them. The goal of this study is to participate in the effort to improve climate models by identifying the strengths and weaknesses regarding their representation of snow over Europe.
Thomas Brall, Vladimir Mares, Rolf Bütikofer, and Werner Rühm
The Cryosphere, 15, 4769–4780, https://doi.org/10.5194/tc-15-4769-2021, https://doi.org/10.5194/tc-15-4769-2021, 2021
Short summary
Short summary
Neutrons from secondary cosmic rays, measured at 2660 m a.s.l. at Zugspitze, Germany, are highly affected by the environment, in particular by snow, soil moisture, and mountain shielding. To quantify these effects, computer simulations were carried out, including a sensitivity analysis on snow depth and soil moisture. This provides a possibility for snow depth estimation based on the measured number of secondary neutrons. This method was applied at Zugspitze in 2018.
Nora Helbig, Michael Schirmer, Jan Magnusson, Flavia Mäder, Alec van Herwijnen, Louis Quéno, Yves Bühler, Jeff S. Deems, and Simon Gascoin
The Cryosphere, 15, 4607–4624, https://doi.org/10.5194/tc-15-4607-2021, https://doi.org/10.5194/tc-15-4607-2021, 2021
Short summary
Short summary
The snow cover spatial variability in mountains changes considerably over the course of a snow season. In applications such as weather, climate and hydrological predictions the fractional snow-covered area is therefore an essential parameter characterizing how much of the ground surface in a grid cell is currently covered by snow. We present a seasonal algorithm and a spatiotemporal evaluation suggesting that the algorithm can be applied in other geographic regions by any snow model application.
Adam William Bateson, Daniel L. Feltham, David Schröder, Yanan Wang, Byongjun Hwang, Jeff K. Ridley, and Yevgeny Aksenov
The Cryosphere Discuss., https://doi.org/10.5194/tc-2021-217, https://doi.org/10.5194/tc-2021-217, 2021
Revised manuscript accepted for TC
Short summary
Short summary
Numerical models are used to understand the mechanisms that drive the evolution of the Arctic sea ice cover. The sea ice cover is formed of pieces of ice called floes. Several recent studies have proposed variable floe size models to replace the standard model assumption of a fixed floe size. In this study we show the need to include floe fragmentation processes in these variable floe size models and demonstrate that model design can determine the impact of floe size on size ice evolution.
Arne Melsom
The Cryosphere, 15, 3785–3796, https://doi.org/10.5194/tc-15-3785-2021, https://doi.org/10.5194/tc-15-3785-2021, 2021
Short summary
Short summary
This study presents new methods to assess how well observations of sea ice expansion are reproduced by results from models. The aim is to provide information about the quality of forecasts for changes in the sea ice extent to operators in or near ice-infested waters. A test using 2 years of model results demonstrates the practical applicability and usefulness of the methods that are presented.
Matthias Scheiter, Marius Schaefer, Eduardo Flández, Deniz Bozkurt, and Ralf Greve
The Cryosphere, 15, 3637–3654, https://doi.org/10.5194/tc-15-3637-2021, https://doi.org/10.5194/tc-15-3637-2021, 2021
Short summary
Short summary
We simulate the current state and future evolution of the Mocho-Choshuenco ice cap in southern Chile (40°S, 72°W) with the ice-sheet model SICOPOLIS. Under different global warming scenarios, we project ice mass losses between 56 % and 97 % by the end of the 21st century. We quantify the uncertainties based on an ensemble of climate models and on the temperature dependence of the equilibrium line altitude. Our results suggest a considerable deglaciation in southern Chile in the next 80 years.
Léo C. P. Martin, Jan Nitzbon, Johanna Scheer, Kjetil S. Aas, Trond Eiken, Moritz Langer, Simon Filhol, Bernd Etzelmüller, and Sebastian Westermann
The Cryosphere, 15, 3423–3442, https://doi.org/10.5194/tc-15-3423-2021, https://doi.org/10.5194/tc-15-3423-2021, 2021
Short summary
Short summary
It is important to understand how permafrost landscapes respond to climate changes because their thaw can contribute to global warming. We investigate how a common permafrost morphology degrades using both field observations of the surface elevation and numerical modeling. We show that numerical models accounting for topographic changes related to permafrost degradation can reproduce the observed changes in nature and help us understand how parameters such as snow influence this phenomenon.
James C. Ferguson and Andreas Vieli
The Cryosphere, 15, 3377–3399, https://doi.org/10.5194/tc-15-3377-2021, https://doi.org/10.5194/tc-15-3377-2021, 2021
Short summary
Short summary
Debris-covered glaciers have a greater extent than their debris-free counterparts due to insulation from the debris cover. However, the transient response to climate change remains poorly understood. We use a numerical model that couples ice dynamics and debris transport and varies the climate signal. We find that debris cover delays the transient response, especially for the extent. However, adding cryokarst features near the terminus greatly enhances the response.
Gunter R. Leguy, William H. Lipscomb, and Xylar S. Asay-Davis
The Cryosphere, 15, 3229–3253, https://doi.org/10.5194/tc-15-3229-2021, https://doi.org/10.5194/tc-15-3229-2021, 2021
Short summary
Short summary
We present numerical features of the Community Ice Sheet Model in representing ocean termini glaciers. Using idealized test cases, we show that applying melt in a partly grounded cell is beneficial, in contrast to recent studies. We confirm that parameterizing partly grounded cells yields accurate ice sheet representation at a grid resolution of ~2 km (arguably 4 km), allowing ice sheet simulations at a continental scale. The choice of basal friction law also influences the ice flow.
Jan-Hendrik Malles and Ben Marzeion
The Cryosphere, 15, 3135–3157, https://doi.org/10.5194/tc-15-3135-2021, https://doi.org/10.5194/tc-15-3135-2021, 2021
Short summary
Short summary
To better estimate the uncertainty in glacier mass change modeling during the 20th century we ran an established model with an ensemble of meteorological data sets. We find that the total ensemble uncertainty, especially in the early 20th century, when glaciological and meteorological observations at glacier locations were sparse, increases considerably compared to individual ensemble runs. This stems from regions with a lot of ice mass but few observations (e.g., Greenland periphery).
Niccolò Tubini, Stephan Gruber, and Riccardo Rigon
The Cryosphere, 15, 2541–2568, https://doi.org/10.5194/tc-15-2541-2021, https://doi.org/10.5194/tc-15-2541-2021, 2021
Short summary
Short summary
We present a new method to compute temperature changes with melting and freezing – a fundamental challenge in cryosphere research – extremely efficiently and with guaranteed correctness of the energy balance for any time step size. This is a key feature since the integration time step can then be chosen according to the timescale of the processes to be studied, from seconds to days.
Jowan M. Barnes, Thiago Dias dos Santos, Daniel Goldberg, G. Hilmar Gudmundsson, Mathieu Morlighem, and Jan De Rydt
The Cryosphere, 15, 1975–2000, https://doi.org/10.5194/tc-15-1975-2021, https://doi.org/10.5194/tc-15-1975-2021, 2021
Short summary
Short summary
Some properties of ice flow models must be initialised using observed data before they can be used to produce reliable predictions of the future. Different models have different ways of doing this, and the process is generally seen as being specific to an individual model. We compare the methods used by three different models and show that they produce similar outputs. We also demonstrate that the outputs from one model can be used in other models without introducing large uncertainties.
Olalekan Babaniyi, Ruanui Nicholson, Umberto Villa, and Noémi Petra
The Cryosphere, 15, 1731–1750, https://doi.org/10.5194/tc-15-1731-2021, https://doi.org/10.5194/tc-15-1731-2021, 2021
Short summary
Short summary
We consider the problem of inferring unknown parameter fields under additional uncertainty for an ice sheet model from synthetic surface ice flow velocity measurements. Our results indicate that accounting for model uncertainty stemming from the presence of nuisance parameters is crucial. Namely our findings suggest that using nominal values for these parameters, as is often done in practice, without taking into account the resulting modeling error can lead to overconfident and biased results.
Sebastian H. R. Rosier, Ronja Reese, Jonathan F. Donges, Jan De Rydt, G. Hilmar Gudmundsson, and Ricarda Winkelmann
The Cryosphere, 15, 1501–1516, https://doi.org/10.5194/tc-15-1501-2021, https://doi.org/10.5194/tc-15-1501-2021, 2021
Short summary
Short summary
Pine Island Glacier has contributed more to sea-level rise over the past decades than any other glacier in Antarctica. Ice-flow modelling studies have shown that it can undergo periods of rapid mass loss, but no study has shown that these future changes could cross a tipping point and therefore be effectively irreversible. Here, we assess the stability of Pine Island Glacier, quantifying the changes in ocean temperatures required to cross future tipping points using statistical methods.
Jan Nitzbon, Moritz Langer, Léo C. P. Martin, Sebastian Westermann, Thomas Schneider von Deimling, and Julia Boike
The Cryosphere, 15, 1399–1422, https://doi.org/10.5194/tc-15-1399-2021, https://doi.org/10.5194/tc-15-1399-2021, 2021
Short summary
Short summary
We used a numerical model to investigate how small-scale landscape heterogeneities affect permafrost thaw under climate-warming scenarios. Our results show that representing small-scale heterogeneities in the model can decide whether a landscape is water-logged or well-drained in the future. This in turn affects how fast permafrost thaws under warming. Our research emphasizes the importance of considering small-scale processes in model assessments of permafrost thaw under climate change.
Gong Cheng, Nina Kirchner, and Per Lötstedt
The Cryosphere, 15, 715–742, https://doi.org/10.5194/tc-15-715-2021, https://doi.org/10.5194/tc-15-715-2021, 2021
Short summary
Short summary
We present an inverse modeling approach to improve the understanding of spatiotemporally variable processes at the inaccessible base of an ice sheet by determining the sensitivity of direct surface observations to perturbations of basal conditions. Time dependency is proved to be important in these types of problems. The effect of perturbations is analyzed based on analytical and numerical solutions.
Richard Essery, Hyungjun Kim, Libo Wang, Paul Bartlett, Aaron Boone, Claire Brutel-Vuilmet, Eleanor Burke, Matthias Cuntz, Bertrand Decharme, Emanuel Dutra, Xing Fang, Yeugeniy Gusev, Stefan Hagemann, Vanessa Haverd, Anna Kontu, Gerhard Krinner, Matthieu Lafaysse, Yves Lejeune, Thomas Marke, Danny Marks, Christoph Marty, Cecile B. Menard, Olga Nasonova, Tomoko Nitta, John Pomeroy, Gerd Schädler, Vladimir Semenov, Tatiana Smirnova, Sean Swenson, Dmitry Turkov, Nander Wever, and Hua Yuan
The Cryosphere, 14, 4687–4698, https://doi.org/10.5194/tc-14-4687-2020, https://doi.org/10.5194/tc-14-4687-2020, 2020
Short summary
Short summary
Climate models are uncertain in predicting how warming changes snow cover. This paper compares 22 snow models with the same meteorological inputs. Predicted trends agree with observations at four snow research sites: winter snow cover does not start later, but snow now melts earlier in spring than in the 1980s at two of the sites. Cold regions where snow can last until late summer are predicted to be particularly sensitive to warming because the snow then melts faster at warmer times of year.
Guillaume Jouvet, Stefan Röllin, Hans Sahli, José Corcho, Lars Gnägi, Loris Compagno, Dominik Sidler, Margit Schwikowski, Andreas Bauder, and Martin Funk
The Cryosphere, 14, 4233–4251, https://doi.org/10.5194/tc-14-4233-2020, https://doi.org/10.5194/tc-14-4233-2020, 2020
Short summary
Short summary
We show that plutonium is an effective tracer to identify ice originating from the early 1960s at the surface of a mountain glacier after a long time within the ice flow, giving unique information on the long-term former ice motion. Combined with ice flow modelling, the dating can be extended to the entire glacier, and we show that an airplane which crash-landed on the Gauligletscher in 1946 will likely soon be released from the ice close to the place where pieces have emerged in recent years.
Yoni Verhaegen, Philippe Huybrechts, Oleg Rybak, and Victor V. Popovnin
The Cryosphere, 14, 4039–4061, https://doi.org/10.5194/tc-14-4039-2020, https://doi.org/10.5194/tc-14-4039-2020, 2020
Short summary
Short summary
We use a numerical flow model to simulate the behaviour of the Djankuat Glacier, a WGMS reference glacier situated in the North Caucasus (Republic of Kabardino-Balkaria, Russian Federation), in response to past, present and future climate conditions (1752–2100 CE). In particular, we adapt a more sophisticated and physically based debris model, which has not been previously applied in time-dependent numerical flow line models, to look at the impact of a debris cover on the glacier’s evolution.
Clemens Schannwell, Reinhard Drews, Todd A. Ehlers, Olaf Eisen, Christoph Mayer, Mika Malinen, Emma C. Smith, and Hannes Eisermann
The Cryosphere, 14, 3917–3934, https://doi.org/10.5194/tc-14-3917-2020, https://doi.org/10.5194/tc-14-3917-2020, 2020
Short summary
Short summary
To reduce uncertainties associated with sea level rise projections, an accurate representation of ice flow is paramount. Most ice sheet models rely on simplified versions of the underlying ice flow equations. Due to the high computational costs, ice sheet models based on the complete ice flow equations have been restricted to < 1000 years. Here, we present a new model setup that extends the applicability of such models by an order of magnitude, permitting simulations of 40 000 years.
Jean-François Lemieux, L. Bruno Tremblay, and Mathieu Plante
The Cryosphere, 14, 3465–3478, https://doi.org/10.5194/tc-14-3465-2020, https://doi.org/10.5194/tc-14-3465-2020, 2020
Short summary
Short summary
Sea ice pressure poses great risk for navigation; it can lead to ship besetting and damages. Sea ice forecasting systems can predict the evolution of pressure. However, these systems have low spatial resolution (a few km) compared to the dimensions of ships. We study the downscaling of pressure from the km-scale to scales relevant for navigation. We find that the pressure applied on a ship beset in heavy ice conditions can be markedly larger than the pressure predicted by the forecasting system.
Louis Quéno, Charles Fierz, Alec van Herwijnen, Dylan Longridge, and Nander Wever
The Cryosphere, 14, 3449–3464, https://doi.org/10.5194/tc-14-3449-2020, https://doi.org/10.5194/tc-14-3449-2020, 2020
Short summary
Short summary
Deep ice layers may form in the snowpack due to preferential water flow with impacts on the snowpack mechanical, hydrological and thermodynamical properties. We studied their formation and evolution at a high-altitude alpine site, combining a comprehensive observation dataset at a daily frequency (with traditional snowpack observations, penetration resistance and radar measurements) and detailed snowpack modeling, including a new parameterization of ice formation in the 1-D SNOWPACK model.
Brandon Berg and Jeremy Bassis
The Cryosphere, 14, 3209–3213, https://doi.org/10.5194/tc-14-3209-2020, https://doi.org/10.5194/tc-14-3209-2020, 2020
Short summary
Short summary
Computer models of ice sheets and glaciers are an important component of projecting sea level rise due to climate change. For models that seek to simulate the full balance of forces within the ice, if portions of the glacier are allowed to quickly break off in a process called iceberg calving, a numerical issue arises that can cause inaccurate results. We examine the issue and propose a solution so that future models can more accurately predict the future behavior of ice sheets and glaciers.
David Parkes and Hugues Goosse
The Cryosphere, 14, 3135–3153, https://doi.org/10.5194/tc-14-3135-2020, https://doi.org/10.5194/tc-14-3135-2020, 2020
Short summary
Short summary
Direct records of glacier changes rarely go back more than the last 100 years and are few and far between. We used a sophisticated glacier model to simulate glacier length changes over the last 1000 years for those glaciers that we do have long-term records of, to determine whether the model can run in a stable, realistic way over a long timescale, reproducing recent observed trends. We find that post-industrial changes are larger than other changes in this time period driven by recent warming.
Eleanor J. Burke, Yu Zhang, and Gerhard Krinner
The Cryosphere, 14, 3155–3174, https://doi.org/10.5194/tc-14-3155-2020, https://doi.org/10.5194/tc-14-3155-2020, 2020
Short summary
Short summary
Permafrost will degrade under future climate change. This will have implications locally for the northern high-latitude regions and may well also amplify global climate change. There have been some recent improvements in the ability of earth system models to simulate the permafrost physical state, but further model developments are required. Models project the thawed volume of soil in the top 2 m of permafrost will increase by 10 %–40 % °C−1 of global mean surface air temperature increase.
Vincent Verjans, Amber A. Leeson, Christopher Nemeth, C. Max Stevens, Peter Kuipers Munneke, Brice Noël, and Jan Melchior van Wessem
The Cryosphere, 14, 3017–3032, https://doi.org/10.5194/tc-14-3017-2020, https://doi.org/10.5194/tc-14-3017-2020, 2020
Short summary
Short summary
Ice sheets are covered by a firn layer, which is the transition stage between fresh snow and ice. Accurate modelling of firn density properties is important in many glaciological aspects. Current models show disagreements, are mostly calibrated to match specific observations of firn density and lack thorough uncertainty analysis. We use a novel calibration method for firn models based on a Bayesian statistical framework, which results in improved model accuracy and in uncertainty evaluation.
Surendra Adhikari, Erik R. Ivins, Eric Larour, Lambert Caron, and Helene Seroussi
The Cryosphere, 14, 2819–2833, https://doi.org/10.5194/tc-14-2819-2020, https://doi.org/10.5194/tc-14-2819-2020, 2020
Short summary
Short summary
The mathematical formalism presented in this paper aims at simplifying computational strategies for tracking ice–ocean mass exchange in the Earth system. To this end, we define a set of generic, and quite simple, descriptions of evolving land, ocean and ice interfaces and present a unified method to compute the sea-level contribution of evolving ice sheets. The formalism can be applied to arbitrary geometries and at all timescales.
John Erich Christian, Alexander A. Robel, Cristian Proistosescu, Gerard Roe, Michelle Koutnik, and Knut Christianson
The Cryosphere, 14, 2515–2535, https://doi.org/10.5194/tc-14-2515-2020, https://doi.org/10.5194/tc-14-2515-2020, 2020
Short summary
Short summary
We use simple, physics-based models to compare how marine-terminating glaciers respond to changes at their marine margin vs. inland surface melt. Initial glacier retreat is more rapid for ocean changes than for inland changes, but in both cases, glaciers will continue responding for millennia. We analyze several implications of these differing pathways of change. In particular, natural ocean variability must be better understood to correctly identify the anthropogenic role in glacier retreat.
Clara Burgard, Dirk Notz, Leif T. Pedersen, and Rasmus T. Tonboe
The Cryosphere, 14, 2369–2386, https://doi.org/10.5194/tc-14-2369-2020, https://doi.org/10.5194/tc-14-2369-2020, 2020
Short summary
Short summary
The high disagreement between observations of Arctic sea ice makes it difficult to evaluate climate models with observations. We investigate the possibility of translating the model state into what a satellite could observe. We find that we do not need complex information about the vertical distribution of temperature and salinity inside the ice but instead are able to assume simplified distributions to reasonably translate the simulated sea ice into satellite
language.
Clara Burgard, Dirk Notz, Leif T. Pedersen, and Rasmus T. Tonboe
The Cryosphere, 14, 2387–2407, https://doi.org/10.5194/tc-14-2387-2020, https://doi.org/10.5194/tc-14-2387-2020, 2020
Short summary
Short summary
The high disagreement between observations of Arctic sea ice inhibits the evaluation of climate models with observations. We develop a tool that translates the simulated Arctic Ocean state into what a satellite could observe from space in the form of brightness temperatures, a measure for the radiation emitted by the surface. We find that the simulated brightness temperatures compare well with the observed brightness temperatures. This tool brings a new perspective for climate model evaluation.
Stephen L. Cornford, Helene Seroussi, Xylar S. Asay-Davis, G. Hilmar Gudmundsson, Rob Arthern, Chris Borstad, Julia Christmann, Thiago Dias dos Santos, Johannes Feldmann, Daniel Goldberg, Matthew J. Hoffman, Angelika Humbert, Thomas Kleiner, Gunter Leguy, William H. Lipscomb, Nacho Merino, Gaël Durand, Mathieu Morlighem, David Pollard, Martin Rückamp, C. Rosie Williams, and Hongju Yu
The Cryosphere, 14, 2283–2301, https://doi.org/10.5194/tc-14-2283-2020, https://doi.org/10.5194/tc-14-2283-2020, 2020
Short summary
Short summary
We present the results of the third Marine Ice Sheet Intercomparison Project (MISMIP+). MISMIP+ is one in a series of exercises that test numerical models of ice sheet flow in simple situations. This particular exercise concentrates on the response of ice sheet models to the thinning of their floating ice shelves, which is of interest because numerical models are currently used to model the response to contemporary and near-future thinning in Antarctic ice shelves.
Takehiko Nose, Takuji Waseda, Tsubasa Kodaira, and Jun Inoue
The Cryosphere, 14, 2029–2052, https://doi.org/10.5194/tc-14-2029-2020, https://doi.org/10.5194/tc-14-2029-2020, 2020
Short summary
Short summary
Accurate wave modelling in and near ice-covered ocean requires true sea ice concentration mapping of the model region. The information derived from satellite instruments has considerable uncertainty depending on retrieval algorithms and sensors. This study shows that the accuracy of satellite-retrieved sea ice concentration estimates is a major error source in wave–ice models. A similar feedback effect of sea ice concentration uncertainty may also apply to modelling lower atmospheric conditions.
Alanna V. Alevropoulos-Borrill, Isabel J. Nias, Antony J. Payne, Nicholas R. Golledge, and Rory J. Bingham
The Cryosphere, 14, 1245–1258, https://doi.org/10.5194/tc-14-1245-2020, https://doi.org/10.5194/tc-14-1245-2020, 2020
David M. W. Pritchard, Nathan Forsythe, Greg O'Donnell, Hayley J. Fowler, and Nick Rutter
The Cryosphere, 14, 1225–1244, https://doi.org/10.5194/tc-14-1225-2020, https://doi.org/10.5194/tc-14-1225-2020, 2020
Short summary
Short summary
This study compares different snowpack model configurations applied in the western Himalaya. The results show how even sparse local observations can help to delineate climate input errors from model structure errors, which provides insights into model performance variation. The results also show how interactions between processes affect sensitivities to climate variability in different model configurations, with implications for model selection in climate change projections.
Cited articles
Atchley, A., Coon, E., Painter, S., Harp, D., and Wilson, C.: Influences and interactions of inundation, peat, and snow on active layer thickness, Geophys. Res. Lett., 43, 5116–5123, https://doi.org/10.1002/2016GL068550, 2016.
Bauer, I., Bhatti, J., Swanston, C., Wieder, R., and Preston, C.: Organic Matter Accumulation and Community Change at the Peatland–Upland Interface: Inferences from 14C and 210Pb Dated Profiles, Ecosystems, 12, 636–653, https://doi.org/10.1007/s10021-009-9248-2, 2009.
Beer, C., Lucht, W., Schmullius, C., and Shvidenko, A.: Small net carbon dioxide uptake by Russian forests during 1981–1999, Geophys. Res. Lett., 33, L15403, https://doi.org/10.1029/2006GL026919, 2006.
Beer, C., Fedorov, A., and Torgovkin, Y.: Permafrost temperature and active-layer thickness of Yakutia with 0.5-degree spatial resolution for model evaluation, Earth Syst. Sci. Data, 5, 305–310, https://doi.org/10.5194/essd-5-305-2013, 2013.
Beer, C., Weber, U., Tomelleri, E., Carvalhais, N., Mahecha, M., and Reichstein, M.: Harmonized European Long-Term Climate Data for Assessing the Effect of Changing Temporal Variability on Land–Atmosphere CO2 Fluxes, J. Climate, 27, 4815–4834, https://doi.org/10.1175/JCLI-D-13-00543.1, 2014.
Bell, P. and Hemsley, A. (Eds.): Green Plants – Their Origin and Diversity, 2nd Edn., Cambridge University Press, New York, 2011.
Benscoter, B. and Vitt, D.: Evaluating feathermoss growth: a challenge to traditional methods and implications for the boreal carbon budget, J. Ecol., 95, 151–158, https://doi.org/10.1111/j.1365-2745.2006.01180.x, 2007.
Beringer, J., Lynch, A., Chapin, F., Mack, M., and Bonan, G.: The Representation of Arctic Soils in the Land Surface Model: The Importance of Mosses, J. Climate, 14, 3324–3335, https://doi.org/10.1175/1520-0442(2001)014<3324:TROASI>2.0.CO;2, 2001.
Bernier, P., Desjardins, R., Karimi-Zindashty, Y., Worth, D., Beaudoin, A., Luo, Y., and Wang, S.: Boreal lichen woodlands: A possible negative feedback to climate change in eastern North America, Agr. Forest Meteorol., 151, 521–528, https://doi.org/10.1016/j.agrformet.2010.12.013, 2011.
Bisbee, K., Gower, S., Norman, J., and Nordheim, E.: Environmental controls on ground cover species composition and productivity in a boreal black spruce forest, Oecologia, 129, 261–270, https://doi.org/10.1007/s004420100719, 2001.
Blok, D., Heijmans, M., Schaepman-Strub, G., van Ruijven, J., Parmentier, F., Maximov, T., and Berendse, F.: The Cooling Capacity of Mosses: Controls on Water and Energy Fluxes in a Siberian Tundra Site, Ecosystems, 14, 1055–1065, https://doi.org/10.1007/s10021-011-9463-5, 2011.
Bohn, K., Dyke, J., Pavlick, R., Reineking, B., Reu, B., and Kleidon, A.: The relative importance of seed competition, resource competition and perturbations on community structure, Biogeosciences, 8, 1107–1120, https://doi.org/10.5194/bg-8-1107-2011, 2011.
Bona, K., Fyles, J., Shaw, C., and Kurz, W.: Are Mosses Required to Accurately Predict Upland Black Spruce Forest Soil Carbon in National-Scale Forest C Accounting Models?, Ecosystems, 16, 1071–1086, https://doi.org/10.1007/s10021-013-9668-x, 2013.
Bonan, G.: A biophysical surface energy budget analysis of soil temperature in the boreal forests of interior Alaska, Water Resour. Res., 27, 767–781, https://doi.org/10.1029/91WR00143, 1991.
Bonan, G. and Shugart, H.: Environmental Factors and Ecological Processes in Boreal Forests, Ann. Rev. Ecol. Syst., 20, 1–28, 1989.
Bond-Lamberty, B. and Gower, S.: Estimation of stand-level leaf area for boreal bryophytes, Oecologia, 151, 584–592, https://doi.org/10.1007/s00442-006-0619-5, 2007.
Bond-Lamberty, B., Wang, C., and Gower, S.: Net primary production and net ecosystem production of a boreal black spruce wildfire chronosequence, Global Change Biol., 10, 473–487, https://doi.org/10.1111/j.1529-8817.2003.0742.x, 2004.
Brovkin, V., Raddatz, T., Reick, C., Claussen, M., and Gayler, V.: Global biogeophysical interactions between forest and climate, Geophys. Res. Lett., 36, L07405, https://doi.org/10.1029/2009GL037543, 2009.
Camill, P., Lynch, J., Clark, J., Adams, J., and Jordan, B.: Changes in Biomass, Aboveground Net Primary Production, and Peat Accumulation following Permafrost Thaw in the Boreal Peatlands of Manitoba, Canada, Ecosystems, 4, 461–478, https://doi.org/10.1007/s10021-001-0022-3, 2001.
Carvalhais, N., Forkel, M., Khomik, M., Bellarby, J., Jung, M., Migliavacca, M., Mu, M., Saatchi, S., Santoro, M., Thurner, M., Weber, U., Ahrens, B., Beer, C., Cescatti, A., Randerson, J., and Reichstein, M.: Global covariation of carbon turnover times with climate in terrestrial ecosystems, Nature, 514, 213–217, https://doi.org/10.1038/nature13731, 2014.
Chadburn, S., Burke, E., Essery, R., Boike, J., Langer, M., Heikenfeld, M., Cox, P., and Friedlingstein, P.: An improved representation of physical permafrost dynamics in the JULES land-surface model, Geosci. Model Dev., 8, 1493–1508, https://doi.org/10.5194/gmd-8-1493-2015, 2015a.
Chadburn, S. E., Burke, E. J., Essery, R. L. H., Boike, J., Langer, M., Heikenfeld, M., Cox, P. M., and Friedlingstein, P.: Impact of model developments on present and future simulations of permafrost in a global land-surface model, The Cryosphere, 9, 1505–1521, https://doi.org/10.5194/tc-9-1505-2015, 2015b.
Cowan, I., Lange, O., and Green, T.: Carbon-dioxide exchange in lichens: Determination of transport and carboxylation characteristics, Planta, 187, 282–294, https://doi.org/10.1007/BF00201952, 1992.
Ekici, A., Beer, C., Hagemann, S., Boike, J., Langer, M., and Hauck, C.: Simulating high-latitude permafrost regions by the JSBACH terrestrial ecosystem model, Geosci. Model Dev., 7, 631–647, https://doi.org/10.5194/gmd-7-631-2014, 2014.
FAO, IIASA, ISRIC, ISS-CAS, and JRC: Harmonized world soil database (version 1.1), FAO, Rome, Italy and IIASA, Laxenburg, Austria, http://www.fao.org/nr/land/soils/harmonized-world-soildatabase/en (last access: 10 October 2011), 2009.
Farquhar, G. and von Caemmerer, S.: Modelling of Photosynthetic Response to Environmental Conditions, in: Encyclopedia of Plant Physiology, vol. 12B, edited by: Lange, O., Nobel, P., Osmond, C., and Ziegler, H., Springer, Heidelberg, 1982.
French, H. (Ed.): The periglacial environment, 3rd Edn., John Wiley & Sons, Chichester, 2007.
Frolking, S., Goulden, M., Wofsy, S., Fan, S.-M., Sutton, D., Munger, J., Bazzaz, A., Daube, B., Crill, P., Aber, J., Band, L., X., W., Savage, K., Moore, T., and Harriss, R.: Modelling temporal variability in the carbon balance of a spruce/moss boreal forest, Global Change Biol., 2, 343–366, 1996.
Goll, D., Brovkin, V.and Liski, J., Raddatz, T., Thum, T., and Todd-Brown, K.: Strong dependence of CO2 emissions from anthropogenic land cover change on initial land cover and soil carbon parametrization, Global Biogeochem. Cy., 29, 1511–1523, https://doi.org/10.1002/2014GB004988, 2015.
Goodrich, L.: The influence of snow cover on the ground thermal regime, Can. Geotech. J., 19, 421–432, https://doi.org/10.1139/t82-047, 1982.
Gornall, J., Jónsdóttir, I., Woodin, S., and Van der Wal, R.: Arctic mosses govern below-ground environment and ecosystem processes, Oecologia, 153, 931–941, https://doi.org/10.1007/s00442-007-0785-0, 2007.
Goulden, M. and Crill, P.: Automated measurements of CO2 exchange at the moss surface of a black spruce forest, Tree Physiol., 17, 537–542, https://doi.org/10.1093/treephys/17.8-9.537, 1997.
Gower, S., Vogel, J., Norman, J., Kucharik, C., Steele, S., and Stow, T.: Carbon distribution and aboveground net primary production in aspen, jack pine and black spruce stands in Saskatchewan and Manitoba, Canada, J. Geophys. Res., 102, 29029–29041, https://doi.org/10.1029/97JD02317, 1997.
Gower, S., Krankina, O., Olson, R., Apps, M., Linder, S., and Wang, C.: Net primary production and carbon allocation patterns of boreal forest ecosystems, Ecol. Appl., 11, 1395–1411, 2001.
Grime, J., Rincon, E., and Wickerson, B.: Bryophytes and plant strategy theory, Bot. J. Linnean Soc., 104, 175–186, https://doi.org/10.1111/j.1095-8339.1990.tb02217.x, 1990.
Hagemann, S. and Stacke, T.: Impact of the soil hydrology scheme on simulated soil moisture memory, Clim. Dynam., 44, 1731–1750, https://doi.org/10.1007/s00382-014-2221-6, 2015.
Hermle, S., Lavigne, M., Bernier, P., Bergeron, O., and Paré, D.: Component respiration, ecosystem respiration and net primary production of a mature black spruce forest in northern Quebec, Tree Physiol., 30, 527–540, https://doi.org/10.1093/treephys/tpq002, 2010.
Hinzman, L., Kane, D., Gieck, R., and Everett, K.: Hydrologic and thermal properties of the active layer in the Alaskan Arctic, Cold Reg. Sci. Technol., 19, 95–110, https://doi.org/10.1016/0165-232X(91)90001-W, 1991.
Jorgenson, M., Romanovsky, V., Harden, J., Shur, Y., O'Donnell, J., Schuur, E., Kanevskiy, M., and Marchenko, S.: Resilience and vulnerability of permafrost to climate change, Can. J. Forest Res., 40, 1219–1236, https://doi.org/10.1139/X10-060, 2010.
Knorr, W.: Annual and interannual CO2 exchanges of the terrestrial biosphere: process-based simulations and uncertainties, Global Ecol. Biogeogr., 9, 225–252, 2000.
Kolari, P., Pumpanen, J., Kulmala, L., Ilvesniemi, H., Nikinmaa, E., Grönholm, T., and Hari, P.: Forest floor vegetation plays an important role in photosynthetic production of boreal forests, Forest Ecol. Manage., 221, 241–248, https://doi.org/10.1016/j.foreco.2005.10.021, 2006.
Koshurnikova, N.: Annual Production of Moss Layer in Dark Coniferous Forests of Ket-Chulym Forest District (by the Example of Moss Hylocomium splendens), Biol. Bull., 34, 532–536, https://doi.org/10.1134/S1062359007050184, 2007.
Koven, C., Friedlingstein, P., Ciais, P., Khvorostyanov, D., Krinner, G., and Tarnocai, C.: On the formation of high-latitude soil carbon stocks: Effects of cryoturbation and insulation by organic matter in a land surface model, Geophys. Res. Lett., 36, L21501, https://doi.org/10.1029/2009GL040150, 2009.
Lange, O., Hahn, S., Meyer, A., and Tenhunen, J.: Upland Tundra in the Foothills of the Brooks Range, Alaska, U.S.A.: Lichen Long-Term Photosynthetic CO2 Uptake and Net Carbon Gain, Arct. Alp. Res., 30, 252–261, https://doi.org/10.2307/1551972, 1998.
Mack, M., Treseder, K., Manies, K., Harden, J., Schuur, E., Vogel, J., Randerson, J., and Chapin III, F.: Recovery of aboveground plant biomass and productivity after fire in mesic and dry black spruce forests of interior Alaska, Ecosystems, 11, 209–225, https://doi.org/10.1007/s10021-007-9117-9, 2008.
Meinshausen, M., Smith, S., Calvin, K., Daniel, J., Kainuma, M., Lamarque, J.-F., Matsumoto, K., Montzka, S., Raper, S., Riahi, K., Thomson, A., Velders, G., and van Vuuren, D.: The RCP greenhouse gas concentrations and their extensions from 1765 to 2300, Climatic Change, 109, 213–241, https://doi.org/10.1007/s10584-011-0156-z, 2011.
Mouillot, F. and Field, C.: Fire history and the global carbon budget: a 1° × 1° fire history reconstruction for the 20th century, Global Change Biol., 11, 398–420, https://doi.org/10.1111/j.1365-2486.2005.00920.x, 2005.
Nash III, T. (Ed.): Lichen Biology, 2nd ed., Cambridge University Press, New York, 1996.
O'Connell, K., Gower, S., and Norman, J.: Comparison of Net Primary Production and Light-Use Dynamics of Two Boreal Black Spruce Forest Communities, Ecosystems, 6, 236–247, 2003.
O'Donnell, J., Romanovsky, V., Harden, J., and McGuire, A.: The Effect of Moisture Content on the Thermal Conductivity of Moss and Organic Soil Horizons From Black Spruce Ecosystems in Interior Alaska, Soil Sci., 174, 646–651, 2009.
O'Donnell, J., Harden, J., McGuire, A., Kanevskiy, M., Jorgenson, M., and Xu, X.: The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: implications for post-thaw carbon loss, Global Change Biol., 17, 1461–1474, https://doi.org/10.1111/j.1365-2486.2010.02358.x, 2011.
Oechel, W. and Collins, N.: Comparative CO2 exchange patterns in mosses from two tundra habitats at Barrow, Alaska, Can. J. Bot., 54, 1355–1369, https://doi.org/10.1139/b76-148, 1976.
Oechel, W. and Van Cleve, K.: The role of bryophytes in nutrient cycling in the taiga, in: Forest ecosystems in the Alaskan taiga. A synthesis of structure and function, edited by: Van Cleve, K., Chapin III, F., Flanagan, P., Vierect, L., and Dyrness, C., Springer, New York, 122–137, 1986.
Olson, D., Dinerstein, E., Wikramanayake, E., Burgess, N., Powell, G., Underwood, E., D'Amico, J., Itoua, I., Strand, H., Morrison, J., Loucks, C., Allnutt, T., Ricketts, T., Kura, Y., Lamoreux, J., Wettengel, W., Hedao, P., and Kassem, K.: Terrestrial Ecoregions of the World: A New Map of Life on Earth, BioScience, 51, 933–938, https://doi.org/10.1641/0006-3568(2001)051[0933:TEOTWA]2.0.CO;2, 2001.
Pachauri, R., Allen, M., Barros, V., Broome, J., Cramer, W., Christ, R., Church, J., Clarke, L., Dahe, Q., Dasgupta, P., et al.: Climate Change 2014: Synthesis Report, in: Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, IPCC, Geneva, Switzerland, 2014.
Porada, P., Weber, B., Elbert, W., Pöschl, U., and Kleidon, A.: Estimating global carbon uptake by lichens and bryophytes with a process-based model, Biogeosciences, 10, 6989–7033, https://doi.org/10.5194/bg-10-6989-2013, 2013.
Porada, P., Weber, B., Elbert, W., Pöschl, U., and Kleidon, A.: Estimating Impacts of Lichens and Bryophytes on Global Biogeochemical Cycles of Nitrogen and Phosphorus and on Chemical Weathering, Global Biogeochem. Cy., 28, 71–85, https://doi.org/10.1002/2013GB004705, 2014.
Proctor, M.: The bryophyte paradox: tolerance of desiccation, evasion of drought, Plant Ecol., 151, 41–49, 2000.
Raddatz, T., Reick, C., Knorr, W., Kattge, J., Roeckner, E., Schnur, R., Schnitzler, K.-G., Wetzel, P., and Jungclaus, J.: Will the tropical land biosphere dominate the climate–carbon cycle feedback during the twenty-first century?, Clim. Dynam., 29, 565–574, https://doi.org/10.1007/s00382-007-0247-8, 2007.
Rapalee, G., Steyaert, L., and Hall, F.: Moss and lichen cover mapping at local and regional scales in the boreal forest ecosystem of central Canada, J. Geophys. Res.-Atmos., 106, 33551–33563, https://doi.org/10.1029/2001JD000509, 2001.
Rinke, A., Kuhry, P., and Dethloff, K.: Importance of a soil organic layer for Arctic climate: A sensitivity study with an Arctic RCM, Geophys. Res. Lett., 35, L13709, https://doi.org/10.1029/2008GL034052, 2008.
Rogers, R.: Ecological strategies of lichens, Lichenologist, 22, 149–162, https://doi.org/10.1017/S002428299000010X, 1990.
Ruess, R., Hendrick, R., Burton, A., Pregitzer, K., Sveinbjornsson, B., Allen, M., and Maurer, G.: Coupling fine root dynamics with ecosystem carbon cycling in black spruce forests of interior Alaska, Ecol. Monogr., 73, 643–662, https://doi.org/10.1890/02-4032, 2003.
Schulze, E.-D. and Caldwell, M. M. (Eds.): Ecophysiology of photosynthesis, Springer Science & Business Media, Springer-Verlag, Berlin, Heidelberg, https://doi.org/10.1007/978-3-642-79354-7, 1995.
Schuur, E., Crummer, K., Vogel, J., and Mack, M.: Plant Species Composition and Productivity following Permafrost Thaw and Thermokarst in Alaskan Tundra, Ecosystems, 10, 280–292, https://doi.org/10.1007/s10021-007-9024-0, 2007.
Schuur, E., McGuire, A., Schadel, C., Grosse, G., Harden, J., Hayes, D., Hugelius, G., Koven, C., Kuhry, P., Lawrence, D., Natali, S., Olefeldt, D., Romanovsky, V., Schaefer, K., Turetsky, M., Treat, C., and Vonk, J.: Climate change and the permafrost carbon feedback, Nature, 520, 171–179, https://doi.org/10.1038/nature14338, 2015.
Shaver, G. and Chapin III, F.: Production: Biomass relationships and element cycling in contrasting arctic vegetation types, Ecol. Monogr., 61, 1–31, https://doi.org/10.2307/1942997, 1991.
Skre, O. and Oechel, W.: Moss production in a black spruce Picea mariana forest with permafrost near Fairbanks, Alaska, as compared with two permafrost-free stands, Ecography, 2, 249–254, https://doi.org/10.1111/j.1600-0587.1979.tb01296.x, 1979.
Soudzilovskaia, N., van Bodegom, P., and Cornelissen, J.: Dominant bryophyte control over high-latitude soil temperature fluctuations predicted by heat transfer traits, field moisture regime and laws of thermal insulation, Funct. Ecol., 27, 1442–1454, https://doi.org/10.1111/1365-2435.12127, 2013.
Stoy, P., Street, L., Johnson, A., Prieto-Blanco, A., and Ewing, S.: Temperature, Heat Flux, and Reflectance of Common Subarctic Mosses and Lichens under Field Conditions: Might Changes to Community Composition Impact Climate-Relevant Surface Fluxes?, Arct. Antarct. Alp. Res., 44, 500–508, https://doi.org/10.1657/1938-4246-44.4.500, 2012.
Street, L., Stoy, P., Sommerkorn, M., Fletcher, B., Sloan, V. L., Hill, T., and Williams, M.: Seasonal bryophyte productivity in the sub-Arctic: A comparison with vascular plants, Funct. Ecol., 26, 365–378, https://doi.org/10.1111/j.1365-2435.2011.01954.x, 2012.
Swanson, R. and Flanagan, L.: Environmental regulation of carbon dioxide exchange at the forest floor in a boreal black spruce ecosystem, Agr. Forest Meteorol., 108, 165–181, https://doi.org/10.1016/S0168-1923(01)00243-X, 2001.
Trumbore, S. and Harden, J.: Accumulation and turnover of carbon in organic and mineral soils of the BOREAS northern study area, J. Geophys. Res.-Atmos., 102, 28817–28830, https://doi.org/10.1029/97JD02231, 1997.
Turetsky, M., Mack, M., Hollingsworth, T., and Harden, J.: The role of mosses in ecosystem succession and function in Alaska's boreal forest, Can. J. Forest Res., 40, 1237–1264, https://doi.org/10.1139/X10-072, 2010.
Uchida, M., Muraoka, H., Nakatsubo, T., Bekku, Y., Ueno, T., Kanda, H., and Koizumi, H.: Net Photosynthesis, Respiration, and Production of the Moss Sanionia uncinata on a Glacier Foreland in the High Arctic, Ny-Ålesund, Svalbard, Arct. Antarct. Alp. Res., 34, 287–292, https://doi.org/10.2307/1552486, 2002.
Uchida, M., Nakatsubo, T., Kanda, H., and Koizumi, H.: Estimation of the annual primary production of the lichen Cetrariella delisei in a glacier foreland in the High Arctic, Ny-Ålesund, Svalbard, Polar Res., 25, 39–49, https://doi.org/10.3402/polar.v25i1.6237, 2006.
Valladares, F., Wierzchos, J., and Ascaso, C.: Porosimetric Study of the Lichen Family Umbilicariaceae: Anatomical Interpretation and Implications for Water Storage Capacity of the Thallus, Am. J. Bot., 80, 263–272, https://doi.org/10.2307/2445349, 1993.
Verseghy, D.: CLASS – A Canadian land surface scheme for GCMs. I. Soil model, Int. J. Climatol., 11, 111–133, https://doi.org/10.1002/joc.3370110202, 1991.
Vogel, J., Bond-Lamberty, B., Schuur, E., Gower, S., Mack, M., O'Connell, K., Valentine, D., and Ruess, R.: Carbon allocation in boreal black spruce forests across regions varying in soil temperature and precipitation, Global Change Biol., 14, 1503–1516, https://doi.org/10.1111/j.1365-2486.2008.01600.x, 2008.
Wahren, C., Walker, M., and Bret-Harte, M.: Vegetation responses in Alaskan arctic tundra after 8 years of a summer warming and winter snow manipulation experiment, Global Change Biol., 11, 537–552, https://doi.org/10.1111/j.1365-2486.2005.00927.x, 2005.
Webb, R., Rosenzweig, C., and Levine, E.: Global Soil Texture and Derived Water-Holding Capacities (Webb et al.), ORNL Distributed Active Archive Center, Oak Ridge, Tennessee, https://doi.org/10.3334/ORNLDAAC/548, 2000.
Williams, T. and Flanagan, L.: Measuring and modelling environmental influences on photosynthetic gas exchange in Sphagnum and Pleurozium, Plant Cell Environ., 21, 555–564, 1998.
Zhu, D., Peng, S., Ciais, P., Viovy, N., Druel, A., Kageyama, M., Krinner, G., Peylin, P., Ottlé, C., Piao, S., Poulter, B., Schepaschenko, D., and Shvidenko, A.: Improving the dynamics of Northern Hemisphere high-latitude vegetation in the ORCHIDEE ecosystem model, Geosci. Model Dev., 8, 2263–2283, https://doi.org/10.5194/gmd-8-2263-2015, 2015.
Short summary
Bryophyte and lichen cover on the forest floor at high latitudes insulates the ground and thus decreases soil temperature. This can protect permafrost soil, stabilising it against global warming. To quantify the insulating effect, we integrate a novel, process-based model of bryophyte and lichen growth into the global land surface model JSBACH. We find an average cooling effect of the bryophyte and lichen cover of 2.7 K, which implies a significant impact on soil temperature at high latitudes.
Bryophyte and lichen cover on the forest floor at high latitudes insulates the ground and thus...