Articles | Volume 8, issue 1
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Response of ice cover on shallow lakes of the North Slope of Alaska to contemporary climate conditions (1950–2011): radar remote-sensing and numerical modeling data analysis
C. M. Surdu
Department of Geography & Environmental Management and Interdisciplinary Centre on Climate Change (IC3), University of Waterloo, Waterloo, Canada
C. R. Duguay
Department of Geography & Environmental Management and Interdisciplinary Centre on Climate Change (IC3), University of Waterloo, Waterloo, Canada
L. C. Brown
Climate Research Division, Environment Canada, Toronto, Canada
D. Fernández Prieto
EO Science, Applications and Future Technologies Department, European Space Agency (ESA), ESA-ESRIN, Frascati, Italy
Cristina M. Surdu, Claude R. Duguay, and Diego Fernández Prieto
The Cryosphere, 10, 941–960,
Vishnu Nandan, Rosemary Willatt, Robbie Mallett, Julienne Stroeve, Torsten Geldsetzer, Randall Scharien, Rasmus Tonboe, John Yackel, Jack Landy, David Clemens-Sewall, Arttu Jutila, David N. Wagner, Daniela Krampe, Marcus Huntemann, Mallik Mahmud, David Jensen, Thomas Newman, Stefan Hendricks, Gunnar Spreen, Amy Macfarlane, Martin Schneebeli, James Mead, Robert Ricker, Michael Gallagher, Claude Duguay, Ian Raphael, Chris Polashenski, Michel Tsamados, Ilkka Matero, and Mario Hoppmann
The Cryosphere, 17, 2211–2229,Short summary
We show that wind redistributes snow on Arctic sea ice, and Ka- and Ku-band radar measurements detect both newly deposited snow and buried snow layers that can affect the accuracy of snow depth estimates on sea ice. Radar, laser, meteorological, and snow data were collected during the MOSAiC expedition. With frequent occurrence of storms in the Arctic, our results show that wind-redistributed snow needs to be accounted for to improve snow depth estimates on sea ice from satellite radars.
Justin Murfitt, Claude Duguay, Ghislain Picard, and Juha Lemmetyinen
The Cryosphere Discuss.,
Revised manuscript under review for TCShort summary
This research focuses on the interaction between microwave signals and lake ice under wet conditions. Field data collected for Lake Oulujärvi in Finland was used to model backscatter under different conditions. The results of the modelling likely indicate that a combination of increased water content and roughness of different interfaces caused backscatter to increase. These results could help to identify areas where lake ice is unsafe for winter transportation.
Maria Shaposhnikova, Claude Duguay, and Pascale Roy-Léveillée
The Cryosphere, 17, 1697–1721,Short summary
We explore lake ice in the Old Crow Flats, Yukon, Canada, using a novel approach that employs radar imagery and deep learning. Results indicate an 11 % increase in the fraction of lake ice that grounds between 1992/1993 and 2020/2021. We believe this is caused by widespread lake drainage and fluctuations in water level and snow depth. This transition is likely to have implications for permafrost beneath the lakes, with a potential impact on methane ebullition and the regional carbon budget.
Yu Cai, Claude R. Duguay, and Chang-Qing Ke
Earth Syst. Sci. Data, 14, 3329–3347,Short summary
Seasonal ice cover is one of the important attributes of lakes in middle- and high-latitude regions. This study used passive microwave brightness temperature measurements to extract the ice phenology for 56 lakes across the Northern Hemisphere from 1979 to 2019. A threshold algorithm was applied according to the differences in brightness temperature between lake ice and open water. The dataset will provide valuable information about the changing ice cover of lakes over the last 4 decades.
Verónica González-Gambau, Estrella Olmedo, Antonio Turiel, Cristina González-Haro, Aina García-Espriu, Justino Martínez, Pekka Alenius, Laura Tuomi, Rafael Catany, Manuel Arias, Carolina Gabarró, Nina Hoareau, Marta Umbert, Roberto Sabia, and Diego Fernández
Earth Syst. Sci. Data, 14, 2343–2368,Short summary
We present the first Soil Moisture and Ocean Salinity Sea Surface Salinity (SSS) dedicated products over the Baltic Sea (ESA Baltic+ Salinity Dynamics). The Baltic+ L3 product covers 9 days in a 0.25° grid. The Baltic+ L4 is derived by merging L3 SSS with sea surface temperature information, giving a daily product in a 0.05° grid. The accuracy of L3 is 0.7–0.8 and 0.4 psu for the L4. Baltic+ products have shown to be useful, covering spatiotemporal data gaps and for validating numerical models.
Justino Martínez, Carolina Gabarró, Antonio Turiel, Verónica González-Gambau, Marta Umbert, Nina Hoareau, Cristina González-Haro, Estrella Olmedo, Manuel Arias, Rafael Catany, Laurent Bertino, Roshin P. Raj, Jiping Xie, Roberto Sabia, and Diego Fernández
Earth Syst. Sci. Data, 14, 307–323,Short summary
Measuring salinity from space is challenging since the sensitivity of the brightness temperature to sea surface salinity is low, but the retrieval of SSS in cold waters is even more challenging. In 2019, the ESA launched a specific initiative called Arctic+Salinity to produce an enhanced Arctic SSS product with better quality and resolution than the available products. This paper presents the methodologies used to produce the new enhanced Arctic SMOS SSS product.
Elena Zakharova, Svetlana Agafonova, Claude Duguay, Natalia Frolova, and Alexei Kouraev
The Cryosphere, 15, 5387–5407,Short summary
The paper investigates the performance of altimetric satellite instruments to detect river ice onset and melting dates and to retrieve ice thickness of the Ob River. This is a first attempt to use satellite altimetry for monitoring ice in the challenging conditions restrained by the object size. A novel approach permitted elaboration of the spatiotemporal ice thickness product for the 400 km river reach. The potential of the product for prediction of ice road operation was demonstrated.
Ingmar Nitze, Sarah W. Cooley, Claude R. Duguay, Benjamin M. Jones, and Guido Grosse
The Cryosphere, 14, 4279–4297,Short summary
In summer 2018, northwestern Alaska was affected by widespread lake drainage which strongly exceeded previous observations. We analyzed the spatial and temporal patterns with remote sensing observations, weather data and lake-ice simulations. The preceding fall and winter season was the second warmest and wettest on record, causing the destabilization of permafrost and elevated water levels which likely led to widespread and rapid lake drainage during or right after ice breakup.
Christian Massari, Luca Brocca, Thierry Pellarin, Gab Abramowitz, Paolo Filippucci, Luca Ciabatta, Viviana Maggioni, Yann Kerr, and Diego Fernandez Prieto
Hydrol. Earth Syst. Sci., 24, 2687–2710,Short summary
Rain gauges are unevenly spaced around the world with extremely low gauge density over places like Africa and South America. Here, water-related problems like floods, drought and famine are particularly severe and able to cause fatalities, migration and diseases. We have developed a rainfall dataset that exploits the synergies between rainfall and soil moisture to provide accurate rainfall observations which can be used to face these problems.
Victor Pellet, Filipe Aires, Simon Munier, Diego Fernández Prieto, Gabriel Jordá, Wouter Arnoud Dorigo, Jan Polcher, and Luca Brocca
Hydrol. Earth Syst. Sci., 23, 465–491,Short summary
This study is an effort for a better understanding and quantification of the water cycle and related processes in the Mediterranean region, by dealing with satellite products and their uncertainties. The aims of the paper are 3-fold: (1) developing methods with hydrological constraints to integrate all the datasets, (2) giving the full picture of the Mediterranean WC, and (3) building a model-independent database that can evaluate the numerous regional climate models (RCMs) for this region.
Carlos Jiménez, Brecht Martens, Diego M. Miralles, Joshua B. Fisher, Hylke E. Beck, and Diego Fernández-Prieto
Hydrol. Earth Syst. Sci., 22, 4513–4533,Short summary
Observing the amount of water evaporated in nature is not easy, and we need to combine accurate local measurements with estimates from satellites, more uncertain but covering larger areas. This is the main topic of our paper, in which local observations are compared with global land evaporation estimates, followed by a weighting of the global observations based on this comparison to attempt derive a more accurate evaporation product.
Brecht Martens, Diego G. Miralles, Hans Lievens, Robin van der Schalie, Richard A. M. de Jeu, Diego Fernández-Prieto, Hylke E. Beck, Wouter A. Dorigo, and Niko E. C. Verhoest
Geosci. Model Dev., 10, 1903–1925,Short summary
Terrestrial evaporation is a key component of the hydrological cycle and reliable data sets of this variable are of major importance. The Global Land Evaporation Amsterdam Model (GLEAM, www.GLEAM.eu) is a set of algorithms which estimates evaporation based on satellite observations. The third version of GLEAM, presented in this study, includes an improved parameterization of different model components. As a result, the accuracy of the GLEAM data sets has been improved upon previous versions.
Kiana Zolfaghari, Claude R. Duguay, and Homa Kheyrollah Pour
Hydrol. Earth Syst. Sci., 21, 377–391,Short summary
A remotely-sensed water clarity value (Kd) was applied to improve FLake model simulations of Lake Erie thermal structure using a time-invariant (constant) annual value as well as monthly values of Kd. The sensitivity of FLake model to Kd values was studied. It was shown that the model is very sensitive to variations in Kd when the value is less than 0.5 m-1.
Jinyang Du, John S. Kimball, Claude Duguay, Youngwook Kim, and Jennifer D. Watts
The Cryosphere, 11, 47–63,Short summary
A new automated method for microwave satellite assessment of lake ice conditions at 5 km resolution was developed for lakes in the Northern Hemisphere. The resulting ice record shows strong agreement with ground observations and alternative ice records. Higher latitude lakes reveal more widespread and larger trends toward shorter ice cover duration than lower latitude lakes. The new approach allows for rapid monitoring of lake ice cover changes, with accuracy suitable for global change studies.
Cristina M. Surdu, Claude R. Duguay, and Diego Fernández Prieto
The Cryosphere, 10, 941–960,
P. Muhammad, C. Duguay, and K.-K. Kang
The Cryosphere, 10, 569–584,Short summary
This study involves the analysis of MODIS Level 3500 m snow products, complemented with 250 m Level 1B data, to monitor ice cover during the break-up period on the Mackenzie River, Canada. Results from the analysis of data for 13 ice seasons (2001–2013) show that ice-off begins between days of year (DOYs) 115 and 125 and ends between DOYs 145 and 155, resulting in average melt durations of about 30–40 days; we conclude that MODIS can monitor ice break-up.
D. G. Miralles, C. Jiménez, M. Jung, D. Michel, A. Ershadi, M. F. McCabe, M. Hirschi, B. Martens, A. J. Dolman, J. B. Fisher, Q. Mu, S. I. Seneviratne, E. F. Wood, and D. Fernández-Prieto
Hydrol. Earth Syst. Sci., 20, 823–842,Short summary
The WACMOS-ET project aims to advance the development of land evaporation estimates on global and regional scales. Evaluation of current evaporation data sets on the global scale showed that they manifest large dissimilarities during conditions of water stress and drought and deficiencies in the way evaporation is partitioned into several components. Different models perform better under different conditions, highlighting the potential for considering biome- or climate-specific model ensembles.
D. Michel, C. Jiménez, D. G. Miralles, M. Jung, M. Hirschi, A. Ershadi, B. Martens, M. F. McCabe, J. B. Fisher, Q. Mu, S. I. Seneviratne, E. F. Wood, and D. Fernández-Prieto
Hydrol. Earth Syst. Sci., 20, 803–822,Short summary
In this study a common reference input data set from satellite and in situ data is used to run four established evapotranspiration (ET) algorithms using sub-daily and daily input on a tower scale as a testbed for a global ET product. The PT-JPL model and GLEAM provide the best performance for satellite and in situ forcing as well as for the different temporal resolutions. PM-MOD and SEBS perform less well: the PM-MOD model generally underestimates, while SEBS generally overestimates ET.
K. A. Luus, Y. Gel, J. C. Lin, R. E. J. Kelly, and C. R. Duguay
Biogeosciences, 10, 7575–7597,
Related subject area
Arctic (e.g. Greenland)Comparing elevation and backscatter retrievals from CryoSat-2 and ICESat-2 over Arctic summer sea iceSummer sea ice floe perimeter density in the Arctic: high-resolution optical satellite imagery and model evaluationPatterns of wintertime Arctic sea-ice leads and their relation to winds and ocean currentsA long-term proxy for sea ice thickness in the Canadian Arctic: 1996–2020Arctic sea ice radar freeboard retrieval from the European Remote-Sensing Satellite (ERS-2) using altimetry: toward sea ice thickness observation from 1995 to 2021Improving modelled albedo over the Greenland ice sheet through parameter optimisation and MODIS snow albedo retrievalsHydraulic suppression of basal glacier melt in sill fjordsDirect measurement of warm Atlantic Intermediate Water close to the grounding line of Nioghalvfjerdsfjorden (79° N) Glacier, northeast GreenlandRapid sea ice changes in the future Barents SeaAssessment of Arctic seasonal snow cover rates of changeSpatially heterogeneous effect of the climate warming on the Arctic land iceCauses and evolution of winter polynyas north of GreenlandWinter Arctic sea ice thickness from ICESat-2: upgrades to freeboard and snow loading estimates and an assessment of the first three winters of data collectionObserved and predicted trends in Icelandic snow conditions for the period 1930–2100Sea ice breakup and freeze-up indicators for users of the Arctic coastal environmentSnow properties at the forest–tundra ecotone: predominance of water vapor fluxes even in deep, moderately cold snowpacksSpatial patterns of snow distribution in the sub-ArcticImproving model-satellite comparisons of sea ice melt onset with a satellite simulatorAccelerated mobilization of organic carbon from retrogressive thaw slumps on the northern Taymyr PeninsulaSnowfall and snow accumulation during the MOSAiC winter and spring seasonsModelling the mass budget and future evolution of Tunabreen, central SpitsbergenKara and Barents sea ice thickness estimation based on CryoSat-2 radar altimeter and Sentinel-1 dual-polarized synthetic aperture radarBrief communication: Preliminary ICESat-2 (Ice, Cloud and land Elevation Satellite-2) measurements of outlet glaciers reveal heterogeneous patterns of seasonal dynamic thickness changeContribution of warm and moist atmospheric flow to a record minimum July sea ice extent of the Arctic in 2020The importance of freeze–thaw cycles for lateral tracer transport in ice-wedge polygonsUncertainties in projected surface mass balance over the polar ice sheets from dynamically downscaled EC-Earth modelsPerspectives on future sea ice and navigability in the ArcticLasting impact of winds on Arctic sea ice through the ocean's memoryHolocene sea-ice dynamics in Petermann Fjord in relation to ice tongue stability and Nares Strait ice arch formationPresentation and evaluation of the Arctic sea ice forecasting system neXtSIM-FComment on “Exceptionally high heat flux needed to sustain the Northeast Greenland Ice Stream” by Smith-Johnsen et al. (2020)Early spring subglacial discharge plumes fuel under-ice primary production at a Svalbard tidewater glacierCombined influence of oceanic and atmospheric circulations on Greenland sea ice concentrationSeasonal changes in sea ice kinematics and deformation in the Pacific sector of the Arctic Ocean in 2018/19Trends and spatial variation in rain-on-snow events over the Arctic Ocean during the early melt seasonThinning leads to calving-style changes at Bowdoin Glacier, GreenlandInter-comparison of snow depth over Arctic sea ice from reanalysis reconstructions and satellite retrievalYear-round impact of winter sea ice thickness observations on seasonal forecastsEnsemble-based estimation of sea-ice volume variations in the Baffin BayThe cryostratigraphy of the Yedoma cliff of Sobo-Sise Island (Lena delta) reveals permafrost dynamics in the central Laptev Sea coastal region during the last 52 kyrPossible impacts of a 1000 km long hypothetical subglacial river valley towards Petermann Glacier in northern GreenlandSea ice drift and arch evolution in the Robeson Channel using the daily coverage of Sentinel-1 SAR data for the 2016–2017 freezing seasonBrief communication: Arctic sea ice thickness internal variability and its changes under historical and anthropogenic forcingSeasonal transition dates can reveal biases in Arctic sea ice simulationsThermokarst lake inception and development in syngenetic ice-wedge polygon terrain during a cooling climatic trend, Bylot Island (Nunavut), eastern Canadian ArcticThe Copernicus Polar Ice and Snow Topography Altimeter (CRISTAL) high-priority candidate missionThe MOSAiC ice floe: sediment-laden survivor from the Siberian shelfSpectral attenuation of ocean waves in pack ice and its application in calibrating viscoelastic wave-in-ice modelsThe current state and 125 kyr history of permafrost on the Kara Sea shelf: modeling constraintsNew observations of the distribution, morphology and dissolution dynamics of cryogenic gypsum in the Arctic Ocean
Geoffrey J. Dawson and Jack C. Landy
The Cryosphere, 17, 4165–4178,Short summary
In this study, we compared measurements from CryoSat-2 and ICESat-2 over Arctic summer sea ice to understand any possible biases between the two satellites. We found that there is a difference when we measure elevation over summer sea ice using CryoSat-2 and ICESat-2, and this is likely due to surface melt ponds. The differences we found were in good agreement with theoretical predictions, and this work will be valuable for summer sea ice thickness measurements from both altimeters.
Yanan Wang, Byongjun Hwang, Adam William Bateson, Yevgeny Aksenov, and Christopher Horvat
The Cryosphere, 17, 3575–3591,Short summary
Sea ice is composed of small, discrete pieces of ice called floes, whose size distribution plays a critical role in the interactions between the sea ice, ocean and atmosphere. This study provides an assessment of sea ice models using new high-resolution floe size distribution observations, revealing considerable differences between them. These findings point not only to the limitations in models but also to the need for more high-resolution observations to validate and calibrate models.
Sascha Willmes, Günther Heinemann, and Frank Schnaase
The Cryosphere, 17, 3291–3308,Short summary
Sea ice is an important constituent of the global climate system. We here use satellite data to identify regions in the Arctic where the sea ice breaks up in so-called leads (i.e., linear cracks) regularly during winter. This information is important because leads determine, e.g., how much heat is exchanged between the ocean and the atmosphere. We here provide first insights into the reasons for the observed patterns in sea-ice leads and their relation to ocean currents and winds.
Isolde A. Glissenaar, Jack C. Landy, David G. Babb, Geoffrey J. Dawson, and Stephen E. L. Howell
The Cryosphere, 17, 3269–3289,Short summary
Observations of large-scale ice thickness have unfortunately only been available since 2003, a short record for researching trends and variability. We generated a proxy for sea ice thickness in the Canadian Arctic for 1996–2020. This is the longest available record for large-scale sea ice thickness available to date and the first record reliably covering the channels between the islands in northern Canada. The product shows that sea ice has thinned by 21 cm over the 25-year record in April.
Marion Bocquet, Sara Fleury, Fanny Piras, Eero Rinne, Heidi Sallila, Florent Garnier, and Frédérique Rémy
The Cryosphere, 17, 3013–3039,Short summary
Sea ice has a large interannual variability, and studying its evolution requires long time series of observations. In this paper, we propose the first method to extend Arctic sea ice thickness time series to the ERS-2 altimeter. The developed method is based on a neural network to calibrate past missions on the current one by taking advantage of their differences during the mission-overlap periods. Data are available as monthly maps for each year during the winter period between 1995 and 2021.
Nina Raoult, Sylvie Charbit, Christophe Dumas, Fabienne Maignan, Catherine Ottlé, and Vladislav Bastrikov
The Cryosphere, 17, 2705–2724,Short summary
Greenland ice sheet melting due to global warming could significantly impact global sea-level rise. The ice sheet's albedo, i.e. how reflective the surface is, affects the melting speed. The ORCHIDEE computer model is used to simulate albedo and snowmelt to make predictions. However, the albedo in ORCHIDEE is lower than that observed using satellites. To correct this, we change model parameters (e.g. the rate of snow decay) to reduce the difference between simulated and observed values.
Johan Nilsson, Eef van Dongen, Martin Jakobsson, Matt O'Regan, and Christian Stranne
The Cryosphere, 17, 2455–2476,Short summary
We investigate how topographical sills suppress basal glacier melt in Greenlandic fjords. The basal melt drives an exchange flow over the sill, but there is an upper flow limit set by the Atlantic Water features outside the fjord. If this limit is reached, the flow enters a new regime where the melt is suppressed and its sensitivity to the Atlantic Water temperature is reduced.
Michael J. Bentley, James A. Smith, Stewart S. R. Jamieson, Margaret R. Lindeman, Brice R. Rea, Angelika Humbert, Timothy P. Lane, Christopher M. Darvill, Jeremy M. Lloyd, Fiamma Straneo, Veit Helm, and David H. Roberts
The Cryosphere, 17, 1821–1837,Short summary
The Northeast Greenland Ice Stream is a major outlet of the Greenland Ice Sheet. Some of its outlet glaciers and ice shelves have been breaking up and retreating, with inflows of warm ocean water identified as the likely reason. Here we report direct measurements of warm ocean water in an unusual lake that is connected to the ocean beneath the ice shelf in front of the 79° N Glacier. This glacier has not yet shown much retreat, but the presence of warm water makes future retreat more likely.
Ole Rieke, Marius Årthun, and Jakob Simon Dörr
The Cryosphere, 17, 1445–1456,Short summary
The Barents Sea is the region of most intense winter sea ice loss, and future projections show a continued decline towards ice-free conditions by the end of this century but with large fluctuations. Here we use climate model simulations to look at the occurrence and drivers of rapid ice change events in the Barents Sea that are much stronger than the average ice loss. A better understanding of these events will contribute to improved sea ice predictions in the Barents Sea.
Chris Derksen and Lawrence Mudryk
The Cryosphere, 17, 1431–1443,Short summary
We examine Arctic snow cover trends through the lens of climate assessments. We determine the sensitivity of change in snow cover extent to year-over-year increases in time series length, reference period, the use of a statistical methodology to improve inter-dataset agreement, version changes in snow products, and snow product ensemble size. By identifying the sensitivity to the range of choices available to investigators, we increase confidence in reported Arctic snow extent changes.
Damien Maure, Christoph Kittel, Clara Lambin, Alison Delhasse, and Xavier Fettweis
The Cryosphere Discuss.,
Revised manuscript accepted for TCShort summary
The Arctic is warming faster than the rest of the Earth. Studies have already shown that Greenland and the Canadian Arctic are experiencing a record increase in melting rates, while Svalbard has been less impacted. Looking at those regions but also extending the study to Iceland and the Russian Arctic Achipelagoes, we see a heterogeneity of the melting rates response to the Arctic warming, with the Russian Archipelagoes experiencing lower melting rates than other regions.
Younjoo J. Lee, Wieslaw Maslowski, John J. Cassano, Jaclyn Clement Kinney, Anthony P. Craig, Samy Kamal, Robert Osinski, Mark W. Seefeldt, Julienne Stroeve, and Hailong Wang
The Cryosphere, 17, 233–253,Short summary
During 1979–2020, four winter polynyas occurred in December 1986 and February 2011, 2017, and 2018 north of Greenland. Instead of ice melting due to the anomalous warm air intrusion, the extreme wind forcing resulted in greater ice transport offshore. Based on the two ensemble runs, representing a 1980s thicker ice vs. a 2010s thinner ice, a dominant cause of these winter polynyas stems from internal variability of atmospheric forcing rather than from the forced response to a warming climate.
Alek A. Petty, Nicole Keeney, Alex Cabaj, Paul Kushner, and Marco Bagnardi
The Cryosphere, 17, 127–156,Short summary
We present upgrades to winter Arctic sea ice thickness estimates from NASA's ICESat-2. Our new thickness results show better agreement with independent data from ESA's CryoSat-2 compared to our first data release, as well as new, very strong comparisons with data collected by moorings in the Beaufort Sea. We analyse three winters of thickness data across the Arctic, including 50 cm thinning of the multiyear ice over this 3-year period.
Darri Eythorsson, Sigurdur M. Gardarsson, Andri Gunnarsson, and Oli Gretar Blondal Sveinsson
The Cryosphere, 17, 51–62,Short summary
In this study we researched past and predicted snow conditions in Iceland based on manual snow observations recorded in Iceland and compared these with satellite observations. Future snow conditions were predicted through numerical computer modeling based on climate models. The results showed that average snow depth and snow cover frequency have increased over the historical period but are projected to significantly decrease when projected into the future.
John E. Walsh, Hajo Eicken, Kyle Redilla, and Mark Johnson
The Cryosphere, 16, 4617–4635,Short summary
Indicators for the start and end of annual breakup and freeze-up of sea ice at various coastal locations around the Arctic are developed. Relative to broader offshore areas, some of the coastal indicators show an earlier freeze-up and later breakup, especially at locations where landfast ice is prominent. However, the trends towards earlier breakup and later freeze-up are unmistakable over the post-1979 period in synthesized metrics of the coastal breakup/freeze-up indicators.
Georg Lackner, Florent Domine, Daniel F. Nadeau, Matthieu Lafaysse, and Marie Dumont
The Cryosphere, 16, 3357–3373,Short summary
We compared the snowpack at two sites separated by less than 1 km, one in shrub tundra and the other one within the boreal forest. Even though the snowpack was twice as thick at the forested site, we found evidence that the vertical transport of water vapor from the bottom of the snowpack to its surface was important at both sites. The snow model Crocus simulates no water vapor fluxes and consequently failed to correctly simulate the observed density profiles.
Katrina E. Bennett, Greta Miller, Robert Busey, Min Chen, Emma R. Lathrop, Julian B. Dann, Mara Nutt, Ryan Crumley, Shannon L. Dillard, Baptiste Dafflon, Jitendra Kumar, W. Robert Bolton, Cathy J. Wilson, Colleen M. Iversen, and Stan D. Wullschleger
The Cryosphere, 16, 3269–3293,Short summary
In the Arctic and sub-Arctic, climate shifts are changing ecosystems, resulting in alterations in snow, shrubs, and permafrost. Thicker snow under shrubs can lead to warmer permafrost because deeper snow will insulate the ground from the cold winter. In this paper, we use modeling to characterize snow to better understand the drivers of snow distribution. Eventually, this work will be used to improve models used to study future changes in Arctic and sub-Arctic snow patterns.
Abigail Smith, Alexandra Jahn, Clara Burgard, and Dirk Notz
The Cryosphere, 16, 3235–3248,Short summary
The timing of Arctic sea ice melt each year is an important metric for assessing how sea ice in climate models compares to satellite observations. Here, we utilize a new tool for creating more direct comparisons between climate model projections and satellite observations of Arctic sea ice, such that the melt onset dates are defined the same way. This tool allows us to identify climate model biases more clearly and gain more information about what the satellites are observing.
Philipp Bernhard, Simon Zwieback, and Irena Hajnsek
The Cryosphere, 16, 2819–2835,Short summary
With climate change, Arctic hillslopes above ice-rich permafrost are vulnerable to enhanced carbon mobilization. In this work elevation change estimates generated from satellite observations reveal a substantial acceleration of carbon mobilization on the Taymyr Peninsula in Siberia between 2010 and 2021. The strong increase occurring in 2020 coincided with a severe Siberian heatwave and highlights that carbon mobilization can respond sharply and non-linearly to increasing temperatures.
David N. Wagner, Matthew D. Shupe, Christopher Cox, Ola G. Persson, Taneil Uttal, Markus M. Frey, Amélie Kirchgaessner, Martin Schneebeli, Matthias Jaggi, Amy R. Macfarlane, Polona Itkin, Stefanie Arndt, Stefan Hendricks, Daniela Krampe, Marcel Nicolaus, Robert Ricker, Julia Regnery, Nikolai Kolabutin, Egor Shimanshuck, Marc Oggier, Ian Raphael, Julienne Stroeve, and Michael Lehning
The Cryosphere, 16, 2373–2402,Short summary
Based on measurements of the snow cover over sea ice and atmospheric measurements, we estimate snowfall and snow accumulation for the MOSAiC ice floe, between November 2019 and May 2020. For this period, we estimate 98–114 mm of precipitation. We suggest that about 34 mm of snow water equivalent accumulated until the end of April 2020 and that at least about 50 % of the precipitated snow was eroded or sublimated. Further, we suggest explanations for potential snowfall overestimation.
Johannes Oerlemans, Jack Kohler, and Adrian Luckman
The Cryosphere, 16, 2115–2126,Short summary
Tunabreen is a 26 km long tidewater glacier. It is the most frequently surging glacier in Svalbard, with four documented surges in the past 100 years. We have modelled this glacier to find out how it reacts to future climate change. Careful calibration was done against the observed length record for the past 100 years. For a 50 m increase in the equilibrium line altitude (ELA) the length of the glacier will be shortened by 10 km after about 100 years.
Juha Karvonen, Eero Rinne, Heidi Sallila, Petteri Uotila, and Marko Mäkynen
The Cryosphere, 16, 1821–1844,Short summary
We propose a method to provide sea ice thickness (SIT) estimates over a test area in the Arctic utilizing radar altimeter (RA) measurement lines and C-band SAR imagery. The RA data are from CryoSat-2, and SAR imagery is from Sentinel-1. By combining them we get a SIT grid covering the whole test area instead of only narrow measurement lines from RA. This kind of SIT estimation can be extended to cover the whole Arctic (and Antarctic) for operational SIT monitoring.
Christian J. Taubenberger, Denis Felikson, and Thomas Neumann
The Cryosphere, 16, 1341–1348,Short summary
Outlet glaciers are projected to account for half of the total ice loss from the Greenland Ice Sheet over the 21st century. We classify patterns of seasonal dynamic thickness changes of outlet glaciers using new observations from the Ice, Cloud and land Elevation Satellite-2 (ICESat-2). Our results reveal seven distinct patterns that differ across glaciers even within the same region. Future work can use our results to improve our understanding of processes that drive seasonal ice sheet changes.
Yu Liang, Haibo Bi, Haijun Huang, Ruibo Lei, Xi Liang, Bin Cheng, and Yunhe Wang
The Cryosphere, 16, 1107–1123,Short summary
A record minimum July sea ice extent, since 1979, was observed in 2020. Our results reveal that an anomalously high advection of energy and water vapor prevailed during spring (April to June) 2020 over regions with noticeable sea ice retreat. The large-scale atmospheric circulation and cyclones act in concert to trigger the exceptionally warm and moist flow. The convergence of the transport changed the atmospheric characteristics and the surface energy budget, thus causing a severe sea ice melt.
Elchin E. Jafarov, Daniil Svyatsky, Brent Newman, Dylan Harp, David Moulton, and Cathy Wilson
The Cryosphere, 16, 851–862,Short summary
Recent research indicates the importance of lateral transport of dissolved carbon in the polygonal tundra, suggesting that the freeze-up period could further promote lateral carbon transport. We conducted subsurface tracer simulations on high-, flat-, and low-centered polygons to test the importance of the freeze–thaw cycle and freeze-up time for tracer mobility. Our findings illustrate the impact of hydraulic and thermal gradients on tracer mobility, as well as of the freeze-up time.
Fredrik Boberg, Ruth Mottram, Nicolaj Hansen, Shuting Yang, and Peter L. Langen
The Cryosphere, 16, 17–33,Short summary
Using the regional climate model HIRHAM5, we compare two versions (v2 and v3) of the global climate model EC-Earth for the Greenland and Antarctica ice sheets. We are interested in the surface mass balance of the ice sheets due to its importance when making estimates of future sea level rise. We find that the end-of-century change in the surface mass balance for Antarctica is 420 Gt yr−1 (v2) and 80 Gt yr−1 (v3), and for Greenland it is −290 Gt yr−1 (v2) and −1640 Gt yr−1 (v3).
Jinlei Chen, Shichang Kang, Wentao Du, Junming Guo, Min Xu, Yulan Zhang, Xinyue Zhong, Wei Zhang, and Jizu Chen
The Cryosphere, 15, 5473–5482,Short summary
Sea ice is retreating with rapid warming in the Arctic. It will continue and approach the worst predicted pathway released by the IPCC. The irreversible tipping point might show around 2060 when the oldest ice will have completely disappeared. It has a huge impact on human production. Ordinary merchant ships will be able to pass the Northeast Passage and Northwest Passage by the midcentury, and the opening time will advance to the next 10 years for icebreakers with moderate ice strengthening.
Qiang Wang, Sergey Danilov, Longjiang Mu, Dmitry Sidorenko, and Claudia Wekerle
The Cryosphere, 15, 4703–4725,Short summary
Using simulations, we found that changes in ocean freshwater content induced by wind perturbations can significantly affect the Arctic sea ice drift, thickness, concentration and deformation rates years after the wind perturbations. The impact is through changes in sea surface height and surface geostrophic currents and the most pronounced in warm seasons. Such a lasting impact might become stronger in a warming climate and implies the importance of ocean initialization in sea ice prediction.
Henrieka Detlef, Brendan Reilly, Anne Jennings, Mads Mørk Jensen, Matt O'Regan, Marianne Glasius, Jesper Olsen, Martin Jakobsson, and Christof Pearce
The Cryosphere, 15, 4357–4380,Short summary
Here we examine the Nares Strait sea ice dynamics over the last 7000 years and their implications for the late Holocene readvance of the floating part of Petermann Glacier. We propose that the historically observed sea ice dynamics are a relatively recent feature, while most of the mid-Holocene was marked by variable sea ice conditions in Nares Strait. Nonetheless, major advances of the Petermann ice tongue were preceded by a shift towards harsher sea ice conditions in Nares Strait.
Timothy Williams, Anton Korosov, Pierre Rampal, and Einar Ólason
The Cryosphere, 15, 3207–3227,Short summary
neXtSIM (neXt-generation Sea Ice Model) includes a novel and extremely realistic way of modelling sea ice dynamics – i.e. how the sea ice moves and deforms in response to the drag from winds and ocean currents. It has been developed over the last few years for a variety of applications, but this paper represents its first demonstration in a forecast context. We present results for the time period from November 2018 to June 2020 and show that it agrees well with satellite observations.
Paul D. Bons, Tamara de Riese, Steven Franke, Maria-Gema Llorens, Till Sachau, Nicolas Stoll, Ilka Weikusat, Julien Westhoff, and Yu Zhang
The Cryosphere, 15, 2251–2254,Short summary
The modelling of Smith-Johnson et al. (The Cryosphere, 14, 841–854, 2020) suggests that a very large heat flux of more than 10 times the usual geothermal heat flux is required to have initiated or to control the huge Northeast Greenland Ice Stream. Our comparison with known hotspots, such as Iceland and Yellowstone, shows that such an exceptional heat flux would be unique in the world and is incompatible with known geological processes that can raise the heat flux.
Tobias Reiner Vonnahme, Emma Persson, Ulrike Dietrich, Eva Hejdukova, Christine Dybwad, Josef Elster, Melissa Chierici, and Rolf Gradinger
The Cryosphere, 15, 2083–2107,Short summary
We describe the impact of subglacial discharge in early spring on a sea-ice-covered fjord on Svalbard by comparing a site influenced by a shallow tidewater glacier with two reference sites. We found a moderate under-ice phytoplankton bloom at the glacier front, which we attribute to subglacial upwelling of nutrients; a strongly stratified surface layer; and higher light penetration. In contrast, sea ice algae biomass was limited by low salinities and brine volumes.
Sourav Chatterjee, Roshin P. Raj, Laurent Bertino, Sebastian H. Mernild, Meethale Puthukkottu Subeesh, Nuncio Murukesh, and Muthalagu Ravichandran
The Cryosphere, 15, 1307–1319,Short summary
Sea ice in the Greenland Sea (GS) is important for its climatic (fresh water), economical (shipping), and ecological contribution (light availability). The study proposes a mechanism through which sea ice concentration in GS is partly governed by the atmospheric and ocean circulation in the region. The mechanism proposed in this study can be useful for assessing the sea ice variability and its future projection in the GS.
Ruibo Lei, Mario Hoppmann, Bin Cheng, Guangyu Zuo, Dawei Gui, Qiongqiong Cai, H. Jakob Belter, and Wangxiao Yang
The Cryosphere, 15, 1321–1341,Short summary
Quantification of ice deformation is useful for understanding of the role of ice dynamics in climate change. Using data of 32 buoys, we characterized spatiotemporal variations in ice kinematics and deformation in the Pacific sector of Arctic Ocean for autumn–winter 2018/19. Sea ice in the south and west has stronger mobility than in the east and north, which weakens from autumn to winter. An enhanced Arctic dipole and weakened Beaufort Gyre in winter lead to an obvious turning of ice drifting.
Tingfeng Dou, Cunde Xiao, Jiping Liu, Qiang Wang, Shifeng Pan, Jie Su, Xiaojun Yuan, Minghu Ding, Feng Zhang, Kai Xue, Peter A. Bieniek, and Hajo Eicken
The Cryosphere, 15, 883–895,Short summary
Rain-on-snow (ROS) events can accelerate the surface ablation of sea ice, greatly influencing the ice–albedo feedback. We found that spring ROS events have shifted to earlier dates over the Arctic Ocean in recent decades, which is correlated with sea ice melt onset in the Pacific sector and most Eurasian marginal seas. There has been a clear transition from solid to liquid precipitation, leading to a reduction in spring snow depth on sea ice by more than −0.5 cm per decade since the 1980s.
Eef C. H. van Dongen, Guillaume Jouvet, Shin Sugiyama, Evgeny A. Podolskiy, Martin Funk, Douglas I. Benn, Fabian Lindner, Andreas Bauder, Julien Seguinot, Silvan Leinss, and Fabian Walter
The Cryosphere, 15, 485–500,Short summary
The dynamic mass loss of tidewater glaciers is strongly linked to glacier calving. We study calving mechanisms under a thinning regime, based on 5 years of field and remote-sensing data of Bowdoin Glacier. Our data suggest that Bowdoin Glacier ungrounded recently, and its calving behaviour changed from calving due to surface crevasses to buoyancy-induced calving resulting from basal crevasses. This change may be a precursor to glacier retreat.
Lu Zhou, Julienne Stroeve, Shiming Xu, Alek Petty, Rachel Tilling, Mai Winstrup, Philip Rostosky, Isobel R. Lawrence, Glen E. Liston, Andy Ridout, Michel Tsamados, and Vishnu Nandan
The Cryosphere, 15, 345–367,Short summary
Snow on sea ice plays an important role in the Arctic climate system. Large spatial and temporal discrepancies among the eight snow depth products are analyzed together with their seasonal variability and long-term trends. These snow products are further compared against various ground-truth observations. More analyses on representation error of sea ice parameters are needed for systematic comparison and fusion of airborne, in situ and remote sensing observations.
Beena Balan-Sarojini, Steffen Tietsche, Michael Mayer, Magdalena Balmaseda, Hao Zuo, Patricia de Rosnay, Tim Stockdale, and Frederic Vitart
The Cryosphere, 15, 325–344,Short summary
Our study for the first time shows the impact of measured sea ice thickness (SIT) on seasonal forecasts of all the seasons. We prove that the long-term memory present in the Arctic winter SIT is helpful to improve summer sea ice forecasts. Our findings show that realistic SIT initial conditions to start a forecast are useful in (1) improving seasonal forecasts, (2) understanding errors in the forecast model, and (3) recognizing the need for continuous monitoring of world's ice-covered oceans.
Chao Min, Qinghua Yang, Longjiang Mu, Frank Kauker, and Robert Ricker
The Cryosphere, 15, 169–181,Short summary
An ensemble of four estimates of the sea-ice volume (SIV) variations in Baffin Bay from 2011 to 2016 is generated from the locally merged satellite observations, three modeled sea ice thickness sources (CMST, NAOSIM, and PIOMAS) and NSIDC ice drift data (V4). Results show that the net increase of the ensemble mean SIV occurs from October to April with the largest SIV increase in December, and the reduction occurs from May to September with the largest SIV decline in July.
Sebastian Wetterich, Alexander Kizyakov, Michael Fritz, Juliane Wolter, Gesine Mollenhauer, Hanno Meyer, Matthias Fuchs, Aleksei Aksenov, Heidrun Matthes, Lutz Schirrmeister, and Thomas Opel
The Cryosphere, 14, 4525–4551,Short summary
In the present study, we analysed geochemical and sedimentological properties of relict permafrost and ground ice exposed at the Sobo-Sise Yedoma cliff in the eastern Lena delta in NE Siberia. We obtained insight into permafrost aggradation and degradation over the last approximately 52 000 years and the climatic and morphodynamic controls on regional-scale permafrost dynamics of the central Laptev Sea coastal region.
Christopher Chambers, Ralf Greve, Bas Altena, and Pierre-Marie Lefeuvre
The Cryosphere, 14, 3747–3759,Short summary
The topography of the rock below the Greenland ice sheet is not well known. One long valley appears as a line of dips because of incomplete data. So we use ice model simulations that unblock this valley, and these create a watercourse that may represent a form of river over 1000 km long under the ice. When we melt ice at the bottom of the ice sheet only in the deep interior, water can flow down the valley only when the valley is unblocked. It may have developed while an ice sheet was present.
Mohammed E. Shokr, Zihan Wang, and Tingting Liu
The Cryosphere, 14, 3611–3627,Short summary
This paper uses sequential daily SAR images covering the Robeson Channel to quantitatively study kinematics of individual ice floes with exploration of wind influence and the evolution of the ice arch at the entry of the channel. Results show that drift of ice floes within the Robeson Channel and the arch are both significantly influenced by wind. The study highlights the advantage of using the high-resolution daily SAR coverage in monitoring sea ice cover in narrow water passages.
Guillian Van Achter, Leandro Ponsoni, François Massonnet, Thierry Fichefet, and Vincent Legat
The Cryosphere, 14, 3479–3486,Short summary
We document the spatio-temporal internal variability of Arctic sea ice thickness and its changes under anthropogenic forcing, which is key to understanding, and eventually predicting, the evolution of sea ice in response to climate change. The patterns of sea ice thickness variability remain more or less stable during pre-industrial, historical and future periods, despite non-stationarity on short timescales. These patterns start to change once Arctic summer ice-free events occur, after 2050.
Abigail Smith, Alexandra Jahn, and Muyin Wang
The Cryosphere, 14, 2977–2997,Short summary
The annual cycle of Arctic sea ice can be used to gain more information about how climate model simulations of sea ice compare to observations. In some models, the September sea ice area agrees with observations for the wrong reasons because biases in the timing of seasonal transitions compensate for other unrealistic sea ice characteristics. This research was done to provide new process-based metrics of Arctic sea ice using satellite observations, the CESM Large Ensemble, and CMIP6 models.
Frédéric Bouchard, Daniel Fortier, Michel Paquette, Vincent Boucher, Reinhard Pienitz, and Isabelle Laurion
The Cryosphere, 14, 2607–2627,Short summary
We combine lake mapping, landscape observations and sediment core analyses to document the evolution of a thermokarst (thaw) lake in the Canadian Arctic over the last millennia. We conclude that temperature is not the only driver of thermokarst development, as the lake likely started to form during a cooler period around 2000 years ago. The lake is now located in frozen layers with an organic carbon content that is an order of magnitude higher than the usually reported values across the Arctic.
Michael Kern, Robert Cullen, Bruno Berruti, Jerome Bouffard, Tania Casal, Mark R. Drinkwater, Antonio Gabriele, Arnaud Lecuyot, Michael Ludwig, Rolv Midthassel, Ignacio Navas Traver, Tommaso Parrinello, Gerhard Ressler, Erik Andersson, Cristina Martin-Puig, Ole Andersen, Annett Bartsch, Sinead Farrell, Sara Fleury, Simon Gascoin, Amandine Guillot, Angelika Humbert, Eero Rinne, Andrew Shepherd, Michiel R. van den Broeke, and John Yackel
The Cryosphere, 14, 2235–2251,Short summary
The Copernicus Polar Ice and Snow Topography Altimeter will provide high-resolution sea ice thickness and land ice elevation measurements and the capability to determine the properties of snow cover on ice to serve operational products and services of direct relevance to the polar regions. This paper describes the mission objectives, identifies the key contributions the CRISTAL mission will make, and presents a concept – as far as it is already defined – for the mission payload.
Thomas Krumpen, Florent Birrien, Frank Kauker, Thomas Rackow, Luisa von Albedyll, Michael Angelopoulos, H. Jakob Belter, Vladimir Bessonov, Ellen Damm, Klaus Dethloff, Jari Haapala, Christian Haas, Carolynn Harris, Stefan Hendricks, Jens Hoelemann, Mario Hoppmann, Lars Kaleschke, Michael Karcher, Nikolai Kolabutin, Ruibo Lei, Josefine Lenz, Anne Morgenstern, Marcel Nicolaus, Uwe Nixdorf, Tomash Petrovsky, Benjamin Rabe, Lasse Rabenstein, Markus Rex, Robert Ricker, Jan Rohde, Egor Shimanchuk, Suman Singha, Vasily Smolyanitsky, Vladimir Sokolov, Tim Stanton, Anna Timofeeva, Michel Tsamados, and Daniel Watkins
The Cryosphere, 14, 2173–2187,Short summary
In October 2019 the research vessel Polarstern was moored to an ice floe in order to travel with it on the 1-year-long MOSAiC journey through the Arctic. Here we provide historical context of the floe's evolution and initial state for upcoming studies. We show that the ice encountered on site was exceptionally thin and was formed on the shallow Siberian shelf. The analyses presented provide the initial state for the analysis and interpretation of upcoming biogeochemical and ecological studies.
Sukun Cheng, Justin Stopa, Fabrice Ardhuin, and Hayley H. Shen
The Cryosphere, 14, 2053–2069,Short summary
Wave states in ice in polar oceans are mostly studied near the ice edge. However, observations in the internal ice field, where ice morphology is very different from the ice edge, are rare. Recently derived wave data from satellite imagery are easier and cheaper than field studies and provide large coverage. This work presents a way of using these data to have a close view of some key features in the wave propagation over hundreds of kilometers and calibrate models for predicting wave decay.
Anatoliy Gavrilov, Vladimir Pavlov, Alexandr Fridenberg, Mikhail Boldyrev, Vanda Khilimonyuk, Elena Pizhankova, Sergey Buldovich, Natalia Kosevich, Ali Alyautdinov, Mariia Ogienko, Alexander Roslyakov, Maria Cherbunina, and Evgeniy Ospennikov
The Cryosphere, 14, 1857–1873,Short summary
The geocryological study of the Arctic shelf remains insufficient for economic activity. The article presents a study of its evolution by methods of math modeling of heat transfer in rocks. As a result, a model of the evolution and current state of the cryolithozone of the Kara shelf was created based on ideas about the history of its geocryological development over the past 125 kyr. The modeling results are correlated to the available field data and are presented as a geocryological map.
Jutta E. Wollenburg, Morten Iversen, Christian Katlein, Thomas Krumpen, Marcel Nicolaus, Giulia Castellani, Ilka Peeken, and Hauke Flores
The Cryosphere, 14, 1795–1808,Short summary
Based on an observed omnipresence of gypsum crystals, we concluded that their release from melting sea ice is a general feature in the Arctic Ocean. Individual gypsum crystals sank at more than 7000 m d−1, suggesting that they are an important ballast mineral. Previous observations found gypsum inside phytoplankton aggregates at 2000 m depth, supporting gypsum as an important driver for pelagic-benthic coupling in the ice-covered Arctic Ocean.
Arp, C. D., Jones, B. M., Lu, Z., and Whitman, M. S.: Shifting balance of thermokarst lake ice regimes across the Arctic Coastal Plain of northern Alaska, Geophys. Res. Lett., 39, L16503, https://doi.org/10.1029/2012GL052518, 2012.
Assel, R. A., Cronk, K., and Norton, D.: Recent trends in Laurentian Great Lakes ice cover, Clim. Change, 57, 185–204, 2003.
Benson, B. J., Magnuson, J. J., Jensen, O. P., Card, V. M., Hodgkins, G., Korhonen, J., and Granin, N. G.: Extreme events, trends, and variability in Northern Hemisphere lake-ice phenology (1855–2005), Clim. Change, 12, 1–25, 2011.
Bonsal, B. R., Prowse, T. D., Duguay, C. R., and Lacroix, M. P.: Impacts of large-scale teleconnections on freshwater-ice break/freeze-up dates over Canada, J. Hydrol., 330, 340–353, 2006.
Bowling, L. C., Kane, D. L., Gieck, R. E., Hinzman, L. D., and Lettenmaier, D. P.: The role of surface storage in a low-gradient Arctic watershed, Water Resour. Res., 39, 1087, https://doi.org/10.1029/2002WR001466, 2003.
Brown, L. C. and Duguay, C. R.: A comparison of simulated and measured lake ice thickness using a shallow water ice profiler, Hydrol. Process., 25, 2932–2941, 2011a.
Brown, L. C. and Duguay, C. R.: The fate of lake ice in the North American Arctic, The Cryosphere, 5, 869–892, https://doi.org/10.5194/tc-5-869-2011, 2011b.
Brown, R. S., Duguay, C. R., Mueller, R. P., Moulton, L. L., Doucette, P. J., and Tagestad, J. D.: Use of synthetic aperture radar to identify and characterize overwintering areas of fish in ice-covered arctic rivers: a demonstration with broad whitefish and their habitats in the Sagavanirktok River, Alaska, T. Am. Fish. Soc., 139, 1711–1722, 2010.
Callaghan, T. V., Johansson, M., Brown, R. D., Groisman, P. Y., Labba, N., Radionov, V., Bradley, R. S., Blangy, S., Bulygina, O. N., Christensen, T. R., Colman, J. E., Essery, R. L. H., Forbes, B. C., Forchhammer, M. C., Golubev, V. N., Honrath, R. E., Juday, G. P., Meshcherskaya, A. V., Phoenix, G. K., Pomeroy, J., Rautio, A., Robinson, D. A., Schmidt, N. M., Serreze, M. C., Shevchenko, V. P., Shiklomanov, A. I., Shmakin, A. B., Sköld, P., Sturm, M., Woo, M.-K., and Wood, E. F.: Multiple effects of changes in arctic snow cover, Ambio, 40, 32–45, 2011.
Clausi, A., Qin, A. K., Chowdhury, M. S., Yu, P., and Maillard, P.: MAGIC: Map-Guided Ice Classification System, Can. J. Remote Sens., 36, S13–S25, 2010.
Comiso, J. C., Parkinson, C. L., Gersten, R., and Stock, L.: Accelerated decline in the Arctic sea ice cover, Geophys. Res. Lett., 35, https://doi.org/10.1029/2007GL031972, 2008.
Cook, T. L. and Bradley, R. S.: An analysis of past and future changes in the ice cover of two High-Arctic lakes based on synthetic aperture radar (SAR) and Landsat imagery, Arct. Antarct. Alp. Res., 42, 9–18, 2010.
Dufresne, J.-L., Foujols, M.-A., Denvil, S., Caubel, A., Marti, O., Aumont, O, Balkanski, Y., Bekki, S., Bellenger, H., Benshila, R., Bony, S., Bopp, L., Braconnot, P., Brockmann, P., Cadule, P., Cheruy, F., Codron, F., Cozic, A., Cugnet, D., de Noblet, N., Duvel, J.-P., Ethé, C., Fairhead, L., Fichefet, T., Flavoni, S., Friedlingstein, P., Grandpeix, J.-Y.., Guez, L., Guilyardi, E., Hauglustaine, D., Hourdin, F., Idelkadi, A., Ghattas, J., Joussaume, S., Kageyama, M., Krinner, G., Labetoulle, S., Lahellec, A., Lefebvre, M.-P., Lefevre, F., Levy, C., Li, Z.X., Lloyd, J., Lott, F., Madec, G., Mancip, M., Marchand, M., Masson, S., Meurdesoif, Y., Mignot, J., Musat, I., Parouty, S., Polcher, J., Rio, C., Schulz, M., Swingedouw, D., Szopa, S., Talandier, C., Terray, P., and Viovy, N.: Climate change projections using the IPSL-CM5 Earth System Model: from CMIP3 to CMIP5, Clim. Dynam., 40, 2123–2165, 2013.
Duguay, C. R. and Lafleur, P. M.: Determining depth and ice thickness of shallow subarctic lakes using spaceborne optical and SAR data, Int. J. Remote Sens., 24, 475–489, 2003.
Duguay, C. R., Rouse, W. R., Lafleur, P. M., Boudreau, D. L., Crevier, Y., and Pultz, T. J.: Analysis of multi-temporal ERS-1 SAR data of subarctic tundra and forest in the northern Hudson Bay Lowland and implications for climate studies, Can. J. Remote Sens., 25, 21–33, 1999.
Duguay, C. R., Pultz, T. J., Lafleur, P. M., and Drai, D.: RADARSAT backscatter characteristics of ice growing on shallow sub-Arctic lakes, Churchill, Manitoba, Canada, Hydrol. Process., 16, 1631–1644, 2002.
Duguay, C. R., Flato, G. M., Jeffries, M. O., Ménard, P., Morris, K., and Rouse, W. R.: Ice-cover variability on shallow lakes at high latitudes: model simulations and observations, Hydrol. Process., 17, 3465–3483, 2003.
Duguay, C. R., Prowse, T. D., Bonsal, B. R., Brown, R. D., Lacroix, M. P., and Ménard, P.: Recent trends in Canadian lake ice cover, Hydrol. Process., 20, 781–801, 2006.
Duguay, C., Brown, L., Kang, K.-K., and Kheyrollah Pour, H.: The Arctic lake ice, in "State of the climate in 2011", B. Am. Meteorol. Soc., 93, S152–S154, 2012.
Elachi, C. M., Bryan, M. L., and Weeks, W. F.: Imaging radar observations of frozen Arctic lakes, Remote Sens. Environ., 5, 169–175, 1976.
Engram, M., Anthony, K. W., Meyer, F. J., and Grosse, G.: Characterization of L-band synthetic aperture radar (SAR) backscatter from floating and grounded thermokarst lake ice in Arctic Alaska, The Cryosphere, 7, 1741–1752, https://doi.org/10.5194/tc-7-1741-2013, 2013.
Futter, M. N.: Patterns and trends in southern Ontario lake ice phenology, Environ. Monit. Assess., 88, 431–444, 2003.
Gao, S. and Stefan, H. G.: Potential climate change effects on ice covers of five freshwater lakes, J. Hydrol. Eng., 9, 226–234, 2004.
Grosswald, M. G., Hughes, T. J., and Lasca, N. P.: Oriented lake-and-ridge assemblages of the Arctic coastal plains: glacial landforms modified by thermokarst and solifluction, Polar Rec., 35, 215–230, 1999.
Hall, D. K., Fagre, D. B., Klasner, F., Linebaugh, G., and Liston, G. E.: Analysis of ERS 1 synthetic aperture radar data of frozen lakes in northern Montana and implications for climate studies, J. Geophys. Res., 99, 22473–22482, 1994.
Hartmann, B. and Wendler, G.: The significance of the 1976 Pacific climate shift in the climatology of Alaska, J. Climate, 18, 4824–4839, 2005.
Heron, R. and Woo, M. K.: Decay of a High Arctic lake-ice cover: Observations and modelling, J. Glaciol., 40, 283–292, 1994.
Hinkel, K. M., Nelson, F. E., Klene, A. F., and, Bell, J. H.: The urban heat island in winter at Barrow, Alaska, Int. J. Climatol., 23, 1889–1905, 2003.
Hinkel, K. M., Frohn, R. C., Nelson, F. E., Eisner, W. R., and Beck, R. A.: Morphometric and spatial analysis of thaw lakes and drained thaw lake basins in the western Arctic Coastal Plain, Alaska, Permafrost Periglac., 16, 327–341, 2005.
Hinkel, K. M., Jones, B. M., Eisner, W. R., Cuomo, C. J., Beck, R. A., and Frohn, R. C.: Methods to assess natural and anthropogenic thaw lake drainage on the western Arctic Coastal Plain of northern Alaska, J. Geophys. Res., 112, F02S16, https://doi.org/10.1029/2006JF000584, 2007.
Hinkel, K. M., Zheng, L., Yongwei, S., and Evan, A.: Regional lake ice meltout patterns near Barrow, Alaska, Polar Geogr., 35, 1–18, 2012.
Hodgkins, G. A., James, I. C., and Huntington, T. G.: Historical changes in lake ice-out dates as indicators of climate change in New England, 1850–2000, Int. J. Climatol., 22, 1819–1827, 2002.
Hurrell, J. W.: Influence of variations in extratropical wintertime teleconnections on Northern Hemisphere temperature, Geophys. Res. Lett., 23, 665–668, 1996.
Jeffries, M. O. and Morris, K.: Some aspects of ice phenology on ponds in central Alaska, USA, Ann. Glaciol., 46, 397–403, 2007.
Jeffries, M. O., Morris, K., Weeks, W. F., and Wakabayashi, H.: Structural and stratigraphic features and ERS 1 synthetic aperture radar backscatter characteristics of ice growing on shallow lakes in NW Alaska, winter 1991–1992, J. Geophys. Res., 99, 22459–22471, 1994.
Jeffries, M. O., Morris, K., and Liston, G. E.: A method to determine lake depth and water availability on the North Slope of Alaska with spaceborne imaging radar and numerical ice growth modelling, Arctic, 49, 367–374, 1996.
Jeffries, M. O., Zhang, T., Frey, K., and Kozlenko, N.: Estimating late winter heat flow to the atmosphere from the lake-dominated Alaskan North Slope, J. Glaciol., 45, 315–324, 1999.
Jeffries, M. O., Morris, K., and Kozlenko, N.: Ice characteristics and processes, and remote sensing of frozen rivers and lakes, in: Remote Sensing in Northern Hydrology: Measuring Environmental Change, edited by: Duguay, C. R. and Pietroniro, A., Washington, American Geophysical Union, 63–90, 2005.
Jones, B. M., Arp, C. D., Hinkel, K. M., Beck, R. A., Schmutz, J. A., and Winston, B.: Arctic lake physical processes and regimes with implications for winter water availability and management in the National Petroleum Reserve Alaska, Environ. Manage., 43, 1071–1084, 2009.
Jones, B. M., Grosse, G., Arp, C. D., Jones, M. C., Walter, A. K. M., and Romanovsky, V. E.: Modern thermokarst lake dynamics in the continuous permafrost zone, northern Seward Peninsula, J. Geophys. Res., 16, G00M03, https://doi.org/10.1029/2011JG001666, 2011.
Jones, B. M., Gusmeroli, M. A., Arp, C. D., Strozzi, T., Grosse, G., Gaglioti, B. V., and Whitman, B. S.: Classification of freshwater ice conditions on the Alaskan Arctic Coastal Plain using ground penetrating radar and TSX satellite data, Int. J. Remote Sens., 34, 8253–8265, 2013.
Kaufman, D. S., Schneider, D. P., McKay, N. P., Ammann, C. M., Bradley, R. S., Briffa, K. R., and Thomas, E.: Recent warming reverses long-term Arctic cooling, Science, 325, 1236–1239, 2009.
Koenigk, T., Brodeau, L., Graversen, R. G., Karlsson, J., Svensson, G., Tjernström, M., and Willén, K.: Arctic climate change in 21st century CMIP5 simulations with EC-Earth, Clim. Dynam., 40, 2719–2743, 2013.
Labrecque, S., Lacelle, D., Duguay, C. R., Lauriol, B., and Hawkings, J.: Contemporary (1951–2001) evolution of lakes in the Old Crow Basin, northern Yukon, Canada: Remote sensing, numerical modeling, and stable isotope analysis, Arctic, 62, 225–238, 2009.
Latifovic, R. and Pouliot, D.: Analysis of climate change impacts on lake ice phenology in Canada using the historical satellite data record, Remote Sens. Environ., 106, 492–507, 2007.
Lenormand, F., Duguay, C. R., and Gauthier, R.: Development of a historical ice database for the study of climate change in Canada, Hydrol. Process., 16, 3707–3722, 2002.
Liston, G. E., and Sturm, M.: Winter precipitation patterns in arctic Alaska determined from a blowing-snow model and snow-depth observations, J. Hydrometeorol., 3, 646–659, 2002.
Magnuson, J. J., Robertson, D. M., Benson, B. J., Wynne, R. H., Livingstone, D. M., Arai, T., Assel, R. A., Barry, R. G., Virginia Card, V., Kuusisto, E., Granin, N. G., Prowse, T. D., Stewart, K. M., and Vuglinski, V. S.: Historical trends in lake and river ice cover in the Northern Hemisphere, Science, 289, 1743–1746, 2000.
Mellor, J.: Bathymetry of Alaskan Arctic lakes: A key to resource inventory with remote sensing methods, Ph. D. Thesis, Institute of Marine Science, University of Alaska, 1982.
Ménard, P., Duguay, C. R., Flato, G. M., and Rouse, W. R.: Simulation of ice phenology on Great Slave Lake, Northwest Territories, Canada, Hydrol. Process., 16, 3691–3706, 2002.
Mendez, J., Hinzman, L. D., and Kane, D. L.: Evapotranspiration from a wetland complex on the Arctic coastal plain of Alaska, Nord. Hydrol., 29, 303–330, 1998.
Morris, K., Jeffries, M. O., and Weeks, W. F.: Ice processes and growth history on Arctic and sub-Arctic lakes using ERS-1 SAR data, Polar Rec., 31, 115–128, 1995.
Morris, K., Jeffries, M. O., and Duguay, C.: Model simulation of the effects of climate variability and change on lake ice in central Alaska, USA, Ann. Glaciol., 40, 113–118, 2005.
National Climate Data Center (NCDC): Barrow, retrieved from http://www.ncdc.noaa.gov/cdo-web/datasets/ANNUAL/locations (last access: 28 April 2013), 2012.
Noguchi, K., Gel, Y. R., and Duguay, C. R.: Bootstrap-based test for trends in hydrological times series, with application to ice phenology data, J. Hydrol., 410, 150–161, 2011.
Ochilov, S., Svacina, N. A., Duguay, C. R., and Clausi, D. A.: Towards an automated lake ice monitoring system for SAR imagery, Abstract C51A-0474 presented at the 2010 Fall Meeting, AGU, San Francisco, Calif., 13–17 December, 2010.
Overland, J. E., Wang, M., Walsh, J. E., Christensen, J. H., Kattsov, V. M., and Chapman W. L.: Chapter 3: Climate model projections for the Arctic, Snow, Water, Ice and Permafrost in the Arctic (SWIPA), Oslo, Arctic Monitoring and Assessment Programme (AMAP), 2011.
Palecki, M. A. and Barry, R. G.: Freeze-up and break-up of lakes as an index of temperature changes during the transition seasons: A case study for Finland, J. Clim. Appl. Meteorol., 25, 893–902, 1986.
Prowse, T., Alfredsen, K., Beltaos, S., Bonsal, B., Duguay, C., Korhola, A., McNamara, J., Vincent, W. F., Vuglinsky, V., and Weyhenmeyer, G. A.: Arctic freshwater ice and its climatic role, Ambio, 40, 46–52, https://doi.org/10.1007/s13280-011-0214-9, 2011.
Robertson, D. M., Ragotzkie, R. A., and Magnuson, J. J.: Lake ice records used to detect historical and future climatic changes, Clim. Change, 21, 407–427, 1992.
Romanovsky, V. E., Smith, S. L., and Christiansen, H. H.: Permafrost thermal state in the polar Northern Hemisphere during the International Polar Year 2007–2009: A synthesis, Permafrost Periglac., 21, 106–116, 2010.
Rovansek, R. J., Hinzman, L. D., and Kane, D. L.: Hydrology of a tundra wetland complex in the Alaskan Arctic coastal plain, USA., Arctic Alpine Res., 28, 311–317, 1996.
Schindler, D. W. and Smol, J. P.: Cumulative effects of climate warming and other human activities on freshwaters of Arctic and Subarctic North America, Ambio, 35, 160–168, 2006.
Schindler, D. W., Beaty, K. G., Fee, E. J., Cruikshank, D. R., DeBruyn, E. R., Findlay, D. L., and Turner, M. A.: Effects of climatic warming on lakes of the central boreal forest, Science, 250, 967–970, 1990.
Sellmann, P. V., Weeks, W. F., and Campbell, W. J.: Use of side-looking airborne radar to determine lake depth on the Alaskan North Slope, CRREL Special Report (US Army Cold Regions Research and Engineering Laboratory), 230, 1975.
Sen, P. K.: Estimates of the regression coefficient based on Kandall's tau, J. Am. Stat. Assoc., 63, 1379–1389, 1968.
Serreze, M. C., Walsh, J. E., Chapin III, F. S., Osterkamp, T., Dyurgerov, M., Romanovsky, V., Oechel, W. C., Morison, J., Zhang, T., and Barry, R. G.: Observational evidence of recent change in the northern high-latitude environment, Clim. Change, 46, 159–207, 2000.
Serreze, M. C., Holland, M. M., and Stroeve, J.: Perspectives on the Arctic's shrinking sea-ice cover, Science, 315, 1533–1536, 2007.
Smith, L. C., Sheng Y., MacDonald, G. M., and Hinzman, L. D.: Disappearing Arctic lakes, Science, 308, p. 1429, https://doi.org/10.1126/science.1108142, 2005.
Smol, J. P. and Douglas, M. S. V.: Crossing the final ecological threshold in High Arctic ponds, P. Natl. Acad. Sci. USA, 104, 12395–12397, 2007.
Sobiech, J. and Dierking, W.: Monitoring lake-ice decay with imaging radar in the Siberian Arctic, International Symposium on Seasonal Snow and Ice, Lahti, Finland, 28 May 2012–1 June 2012, 2012.
Sturm, M. and Liston, G. E.: The snow cover on lakes of the Arctic Coastal Plain of Alaska, USA., J. Glaciol., 49, 370–380, 2003.
Trenberth, K. E., Jones, P. D., Ambenje, P., Bojariu, R., Easterling, D., Klein Tank, A., Parker, D., Rahimzadeh, F., Renwick, J. A., Rusticucci, M., Soden, B., and Zhai, P.: Observations: Surface and Atmospheric Climate Change, in: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., and Miller, H. L., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2007.
Vavrus, S. J., Wynne, R. H., and Foley, J. A.: Measuring the sensitivity of Southern Wisconsin lake ice to climate variations and lake depth using a numerical model, Limnol. Oceanogr., 41, 822–831, 1996.
Walsh, S. E., Vavrus, S. J., Foley, J. A., Fisher, V. A., Wynne, R. H., and Lenters, J. D.: Global patterns of lake ice phenology and climate: Model simulations and observations, J. Geophys. Res.-Atmos., 103, 28825–28837, 1998.
Walsh, J. E., Overland, J. E., Groisman, P. Y., and Rudolf, B.: Chapter 2: Arctic climate: Recent variations, Snow, Water, Ice and Permafrost in the Arctic (SWIPA), Oslo, Arctic Monitoring and Assessment Programme (AMAP), 2011.
Walter, K. M., Zimov, S. A., Chanton, J. P., Verbyla, D., and Chapin III, F. S.: Methane bubbling from Siberian thaw lakes as a positive feedback to climate warming, Nature, 443, 71–75 https://doi.org/10.1038/nature05040, 2006.
Walter, K. M., Engram, M., Duguay, C. R., Jeffries, M. O., and Chapin, F. S.: The potential use of synthetic aperture radar for estimating methane ebullition from Arctic lakes, J. Am. Water. Resour. As., 44, 305–315, 2008.
Weeks, W. F., Fountain, A. G., Bryan, M. L., and Elachi, C.: Differences in radar returns from ice-covered North Slope lakes, J. Geophys. Res., 83, 4069–4073, 1978.
Wendler, G., Chen, L., and Moore, B.: The First decade of the new century: a cooling trend for most of Alaska, The Open Atmospheric Science Journal, 6, 111–116, 2012.
White, D. M., Prokein, P., Chambers, M. K., Lilly, M. R., and Toniolo, H.: Use of synthetic aperture radar for selecting Alaskan lakes for winter water use, J. Am. Water. Resour. As., 44, 276–284, 2008.
Young, K. L. and Woo, M. K.: Hydrological response of a patchy high arctic wetland, Nord. Hydrol., 31, 317–338, 2000.
Zhang, T. and Jeffries, M. O.: Modeling interdecadal variations of lake ice thickness and sensitivity to climatic change in northernmost Alaska, Ann. Glaciol., 31, 339–347, 2000.