Older ice tends to be thicker and thus more resilient to changes in atmospheric and oceanic forcing compared to younger ice. Processes within the Arctic Basin are a much more likely cause (like increased melting from warmer air and water temperatures). Observations of Arctic sea ice extent have shown decreasing trends in all months and virtually all regions (Meier et al. Sea ice is an important element of the Arctic system because it (1) acts as a barrier between the underlying ocean and the atmosphere, (2) limits the amount of absorbed solar energy during the summer due to its high albedo, (3) provides a habitat for biological activity, (4) limits human access to the Arctic Ocean, and (5) serves as a platform for Indigenous community hunting and travel.

The resolution of the satellite data is low and the moorings are situated within the grid cells for the “79°” JPL ice volume transport time series (Figure 1). Vinje et al. (1998). A lot of the variability during winter, however, is reasonably well reproduced by both data sets. Physics, Astrophysics and Astronomy, Perspectives of Earth and Space Scientists, I have read and accept the Wiley Online Library Terms and Conditions of Use, Arctic sea ice area export through the Fram Strait estimated from satellite‐based data: 1988–2012, Variability and trends in the Arctic sea ice cover: Results from different techniques, Freshwater export in the East Greenland current freshens the North Atlantic, Sea ice drift in the central Arctic using the 89 GHz brightness temperatures of the Advanced Microwave Scanning Radiometer (AMSR‐E)—User's manual, Sea ice drift in the central Arctic combining QuikSCAT and SSM/I sea ice drift data, Arctic freshwater export: Status, mechanisms, and prospects, Variability in categories of Arctic sea ice in Fram Strait, Thinning of Arctic sea ice observed in Fram Strait: 1990‐2011, Time variability in the annual cycle of sea ice thickness in the transpolar, drift, Multi‐satellite sensor analysis of fast ice development in the Norske ice barrier, SSM/I sea ice remote sensing for mesoscale ocean‐atmosphere interaction analysis, Arctic Ocean change heralds North Atlantic freshening, Recent summer sea ice thickness surveys in Fram Strait and associated ice volume fluxes, Summer sea ice motion from the 18 GHz channel of AMSR‐E and the exchange of sea ice between the Pacific and Atlantic sectors, Variability of Arctic sea ice thickness and volume from CryoSat‐2, Thinning and volume loss of the Arctic Ocean sea ice cover: 2003–2008, Sea ice motion from satellite passive microwave imagery assessed with ERS SAR and buoy motions, Arctic sea ice circulation and drift speed: Decadal trends and ocean currents, Arctic sea ice thickness loss determined using subsurface, aircraft, and satellite observations, Measurements of the underside topography of sea ice by moored subsea sonar, Greater role for Atlantic inflows on sea‐ice loss in the Eurasian Basin of the Arctic Ocean, Arctic ocean warming contributes to reduced polar ice cap, Positive trend in the mean speed and deformation rate of Arctic sea ice, 1979–2007, Evidence of Arctic sea ice thinning from direct observations, Satellite‐derived sea ice export and its impact on arctic ice mass balance, Sensitivity of CryoSat‐2 Arctic sea‐ice freeboard and thickness on radar‐waveform interpretation, Uncertainty in modeled Arctic sea ice volume, The large‐scale freshwater cycle of the Arctic, Processes and impacts of Arctic amplification: A research synthesis, Fram Strait sea ice export variability and September Arctic sea ice extent over the last 80 years, Recent wind driven high sea ice area export in the Fram Strait contributes to Arctic sea ice decline, Fram Strait sea ice volume transport based on ULS ice thickness and satellite ice drift [data set], Sea ice remote sensing using AMSR‐E 89‐GHz channels, Fram Strait sea ice volume export estimated between 2003 and 2008 from satellite data, Trends in Arctic sea ice drift and role of wind forcing: 1992–2009, Reassessing sea ice drift and its relationship to long‐term Arctic sea ice loss in coupled climate models, An enhancement to sea ice motion and age products at the National Snow and Ice Data Center (NSIDC), Comparison of Arctic sea ice thickness from satellites, aircraft, and PIOMAS data, Understanding causes and effects of rapid warming in the Arctic, Arctic sea ice volume export through the Fram Strait from combined satellite and model data: 1979–2012.
By far the largest portion (>90%) of the total Arctic sea ice export (Haine et al., 2015; Serreze et al., 2006) takes place through Fram Strait into the Nordic Seas (e.g., Kwok et al., 2004; Spreen et al., 2009). In recent years the moorings in Fram Strait also contain an ADCP that measures the sea ice speed directly (section 2.1.5).

Also the standard deviations of 12.2 and 6.9 km/day for ADCP and satellite data, respectively, are different. 6). The oldest ice (>4 years old), which once dominated within the Arctic Ocean, now makes up just a small fraction of the Arctic Ocean ice pack in March, when the sea ice cover is at its maximum extent (Fig. Potentially, however, also the third process, an enhanced export of ice volume out of the Arctic Ocean could have contributed to the sea ice volume decline. Ricker, R., S. Hendricks, L. Kaleschke, X. Tian-Kunze, J. Properties of Rocks, Computational
This year the percentages are relative to ice in the Arctic Ocean region (Fig. The variability of the Fram Strait sea ice volume export is dominated by the variability of the sea ice drift (e.g., Ricker et al., 2018). Given the shortness of the time series used in calibrating the model, the derived longer term trends should be considered with respect to uncertainties in the inferred regression coefficient between a predictor (SLP gradient) and a predictand (ice transport) variables. For longitudes west of 7°W, the ice thickness from 7°W, and for longitudes east of 2°W, the ice thickness from 2°W is used (i.e., the ice thickness is kept constant toward the Greenland coast and toward the eastern ice edge). Therefore, in situ observations will still be needed in the future. Thus, the ADCP speed is faster by 9.6 km/day on average. The total extent of the oldest ice declined from 2.52 million km2 in March 1985 to 0.09 million km2 in March 2019. We therefore focus our uncertainty assessment and sensitivity studies on different sea ice drift data sets and for the ice area always use the same, well‐established, higher‐resolution ice concentration product. Volume transports in the following are given as being positive toward the south, that is, as sea ice volume export. We thank the Polar Science Center, Applied Physics Laboratory, University of Washington, USA for providing the PIOMAS sea ice volume data set (https://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly/data/). They found a winter (October–April) sea ice volume export of 1,560 ±  180 km3, which was slightly lower than the winter ice volume exports of Vinje et al. Changes in Arctic sea ice volume affect regional heat and freshwater budgets and patterns of atmospheric circulation at lower latitudes.

The PIOMAS ice volume time series is dominated by the seasonal cycle of summer ice melt and winter ice volume growth. This method has been used to provide a record of the age of the ice since the early 1980s (Tschudi et al. (left) Total sea ice volume in the Arctic from 1992 to 2014 obtained from the Pan‐Arctic Ice Ocean Modeling and Assimilation System (PIOMAS), ver 2.1; (Schweiger et al.. At the same time atmosphere (Serreze & Barry, 2011; Wendisch et al., 2017) and ocean (Polyakov et al., 2010, 2017) temperature were increasing, which, in line with process (ii)—melting—could be the main cause for the observed ice volume decrease. Monthly values strongly vary between 324±147  km3 in December and 23±43  km3 in August. The gradient (red) of mean sea ice thickness across Fram Strait based on a linear fit from all ULS observations between 1990 and 2014 is −0.25 m/longitude. Enter your email address below and we will send you your username, If the address matches an existing account you will receive an email with instructions to retrieve your username, The sea ice volume transport is the product of the sea ice drift, area, and thickness data sets described in the following sections, Locations of ULS in Fram Strait (orange dots). The sea ice volume transport is calculated on a daily basis. The modal thickness of the “old ice,” that is, multiyear ice or thicker first‐year ice, in the ice thickness distribution is shown.

Despite low extents, sea ice volume was higher over much of the central Arctic compared to the average since Cryosat-2 measurements began in 2011. The temporal resolution is 1 day, and the spatial resolution of the grid is 25 km. Arctic ecosystems and communities are increasingly at risk due to continued warming and declining sea ice, Archive of previous Arctic Report Cards >, 1Thayer School of Engineering, Dartmouth College, Hanover, NH, USA All trends are significant at a 99% confidence level.

The flux gates in the satellite data follow the polar stereographic data set grid and not a particular latitude. It does not exactly follow a latitude but is centered at 79°N (see Figure 1). Three different satellite ice drift data sets (JPL, NSIDC, IFREMER) are combined with the sea ice thickness from up to four ULS operating simultaneously. The ice area along the flux gate in Fram Strait is calculated from SSM/I and SSMIS satellite microwave radiometer observations. (2009) extended these two time series from the 1990s by inclusion of the satellite ICESat ice thickness for the years 2003 to 2008. Thus, for the given time period, changes in sea ice export do not drive the sea ice volume decrease in the Arctic Basin. (1998) (orange triangles in Figure 7). The largest changes were a decrease in second-year ice (1-2 years old) coverage, from 21.4% in March 2018 to 12.8% in March 2019, and an increase in 3-4 year old ice from 1.3% to 6.3%. 1996; Maslanik and Stroeve 1999).

The standard deviation of the differences are with 286 km2/day and 331 km2/day much larger. The JPL ice drift data set is used.