An Assessment of Sea Ice Motion Products in the Robeson Channel Using Daily Sentinel-1 Images

Sea ice motion is an essential parameter when determining sea ice deformation, regional advection, and the outflow of ice from the Arctic Ocean. The Robeson Channel, which is located between Ellesmere Island and northwest Greenland, is a narrow but crucial channel for ice outflow. Only three Eulerian sea ice motion products derived from ocean/sea ice reanalysis are available: GLORYS12V1, PSY4V3, and TOPAZ4. In this study, we used Lagrangian ice motion in the Robeson Channel derived from Sentinel-1 images to assess GLORYS12V1, PSY4V3, and TOPAZ4. The influence of the presence of ice arches, and wind and tidal forcing on the accuracies of the reanalysis products was also investigated. The results show that the PSY4V3 product performs the best as it underestimates the motion the least, whereas TOPAZ4 grossly underestimates the motion. This is particularly true in regimes of free drift after the formation of the northern arch. In areas with slow ice motion or grounded ice floes, the GLORYS12V1 and TOPAZ4 products offer a better estimation. The spatial distribution of the deviation between the products and ice floe drift is also presented and shows a better agreement in the Robeson Channel compared to the packed ice regime north of the Robeson Channel.

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Recent Sea Ice Decline Did Not Significantly Increase the Total Liquid Freshwater Content of the Arctic Ocean

Journal of Climate ◽

10.1175/jcli-d-18-0237.1 ◽

2018 ◽

Vol 32 (1) ◽

pp. 15-32 ◽

Cited By ~ 11

Author(s):

Qiang Wang ◽

Claudia Wekerle ◽

Sergey Danilov ◽

Dmitry Sidorenko ◽

Nikolay Koldunov ◽

...

Keyword(s):

Spatial Distribution ◽

Sea Ice ◽

Arctic Ocean ◽

Ocean Circulation ◽

General Circulation ◽

The Arctic ◽

Sea Ice Decline ◽

The Arctic Ocean ◽

Eurasian Basin ◽

The Impact

Abstract The freshwater stored in the Arctic Ocean is an important component of the global climate system. Currently the Arctic liquid freshwater content (FWC) has reached a record high since the beginning of the last century. In this study we use numerical simulations to investigate the impact of sea ice decline on the Arctic liquid FWC and its spatial distribution. The global unstructured-mesh ocean general circulation model Finite Element Sea Ice–Ocean Model (FESOM) with 4.5-km horizontal resolution in the Arctic region is applied. The simulations show that sea ice decline increases the FWC by freshening the ocean through sea ice meltwater and modifies upper ocean circulation at the same time. The two effects together significantly increase the freshwater stored in the Amerasian basin and reduce its amount in the Eurasian basin. The salinification of the upper Eurasian basin is mainly caused by the reduction in the proportion of Pacific Water and the increase in that of Atlantic Water (AW). Consequently, the sea ice decline did not significantly contribute to the observed rapid increase in the Arctic total liquid FWC. However, the changes in the Arctic freshwater spatial distribution indicate that the influence of sea ice decline on the ocean environment is remarkable. Sea ice decline increases the amount of Barents Sea branch AW in the upper Arctic Ocean, thus reducing its supply to the deeper Arctic layers. This study suggests that all the dynamical processes sensitive to sea ice decline should be taken into account when understanding and predicting Arctic changes.

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Dissolved Neodymium Isotopes Trace Origin and Spatiotemporal Evolution of Modern Arctic Sea Ice

10.5194/egusphere-egu2020-7782 ◽

2020 ◽

Author(s):

Georgi Laukert ◽

Dorothea Bauch ◽

Ilka Peeken ◽

Thomas Krumpen ◽

Kirstin Werner ◽

...

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Surface Waters ◽

Ice Cores ◽

Arctic Sea Ice ◽

The Arctic ◽

Spatiotemporal Evolution ◽

Arctic Sea ◽

The Arctic Ocean ◽

Ice Floes

The lifetime and thickness of Arctic sea ice have markedly decreased in the recent past. This affects Arctic marine ecosystems and the biological pump, given that sea ice acts as platform and transport medium of marine and atmospheric nutrients. At the same time sea ice reduces light penetration to the Arctic Ocean and restricts ocean/atmosphere exchange. In order to understand the ongoing changes and their implications, reconstructions of source regions and drift trajectories of Arctic sea ice are imperative. Automated ice tracking approaches based on satellite-derived sea-ice motion products (e.g. ICETrack) currently perform well in dense ice fields, but provide limited information at the ice edge or in poorly ice-covered areas. Radiogenic neodymium (Nd) isotopes (&#949;Nd) have the potential to serve as a chemical tracer of sea-ice provenance and thus may provide information beyond what can be expected from satellite-based assessments. This potential results from pronounced &#949;Nd differences between the distinct marine and riverine sources, which feed the surface waters of the different sea-ice formation regions. We present the first dissolved (< 0.45 &#181;m) Nd isotope and concentration data obtained from optically clean Arctic first- and multi-year sea ice (ice cores) collected from different ice floes across the Fram Strait during the RV POLARSTERN cruise PS85 in 2014. Our data confirm the preservation of the seawater &#949;Ndsignatures in sea ice despite low Nd concentrations (on average ~ 6 pmol/kg) resulting from efficient brine rejection. The large range in &#949;Nd signatures (~ -10 to -30) mirrors that of surface waters in various parts of the Arctic Ocean, indicating that differences between ice floes but also between various sections in an individual ice core reflect the origin and evolution of the sea ice over time. Most ice cores have &#949;Nd signatures of around -10, suggesting that the sea ice was formed in well-mixed waters in the central Arctic Ocean and transported directly to the Fram Strait via the Transpolar Drift. Some ice cores, however, also revealed highly unradiogenic signatures (&#949;Nd < ~ -15) in their youngest (bottom) sections, which we attribute to incorporation of meltwater from Greenland into newly grown sea ice layers. Our new approach facilitates the reconstruction of the origin and spatiotemporal evolution of isolated sea-ice floes in the future Arctic.

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The distribution of snow black carbon observed in the Arctic and compared to the GISS-PUCCINI model

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-11245-2012 ◽

2012 ◽

Vol 12 (5) ◽

pp. 11245-11274

Author(s):

T. Dou ◽

C. Xiao ◽

D. T. Shindell ◽

J. Liu ◽

J. Ming ◽

...

Keyword(s):

Spatial Distribution ◽

Sea Ice ◽

Arctic Ocean ◽

Radiative Forcing ◽

Climate Model ◽

The Arctic ◽

Northern Eurasia ◽

Russian Arctic ◽

Radiative Forcings ◽

The Arctic Ocean

Abstract. In this study, we focus on the latest NASA GISS composition-climate model to evaluate its performance in simulating the spatial distribution of snow BC (sBC) in the Arctic relative to present observations. The radiative forcing due to BC deposition to the Arctic snow and sea ice is also estimated. Two sets of model simulations have been done in the analysis, where meteorology is linearly relaxed towards National Centers for Environmental Prediction (NCEP) and towards NASA Modern Era Reanalysis for Research and Applications (MERRA) reanalyses. Results indicate that both of the modeled sBC are in good agreement with present-day observations in and around the Arctic Ocean, except for underestimation at a few sites in the Russian Arctic. The overall ratio of observed to modeled sBC is 1.1. The result from the NCEP run is slightly better than that from the MERRA run. This suggests that the latest GISS-E2-PUCCINI model does not have significant biases in its simulated spatial distribution of BC deposition to the Arctic, and underestimation of biomass burning emissions in Northern Eurasia is preliminarily considered to be the main cause of the simulation biases in the Russian Arctic. The combination of observations and modeling provides a comprehensive distribution of sBC over the Arctic. On the basis of this distribution, we estimate the decrease in snow and sea ice albedo and the resulting radiative forcing. It is concluded that the averaged decrease in snow and sea ice albedo in and around the Arctic Ocean (66–90° N) due to BC deposition is 0.4–0.6% from spring 2007–2009, leading to regional surface radiative forcings of 0.7 W m−2, 1.1 W m−2 and 1.0 W m−2, respectively in spring 2007, 2008 and 2009.

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Influence of synoptic atmospheric conditions on movement of individual sea-ice floes in Fram Strait, late summer 2010

Annals of Glaciology ◽

10.3189/2015aog69a655 ◽

2015 ◽

Vol 56 (69) ◽

pp. 445-450

Author(s):

Jennifer A. King ◽

Grant R. Bigg ◽

Richard Hall

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Late Summer ◽

The Arctic ◽

Boreal Summer ◽

Fram Strait ◽

Atmospheric Conditions ◽

Ice Dynamics ◽

The Arctic Ocean ◽

Ice Floes

AbstractIn this paper we investigate the effect on sea-ice movement of changes in the synoptic atmospheric conditions in late boreal summer 2010. Our study area is the western Fram Strait, a crucial passage for the transport of ice out of the Arctic basin. Ice dynamics here affect the movement of ice in the East Greenland Current, the transpolar drift and ice extent in the Arctic Ocean. In contrast to other times of the year, when the Fram Strait wind field is characterized by strong, persistent northerlies, we show that the weaker, more variable winds typical during late summer for the Fram Strait can slow movement of ice floes out of the area, thus slowing the export of ice from the Arctic Ocean at the end of summer, a time crucial for ice export. The Arctic Ocean could lose even more of the ice that survives the summer if this was not the case. This would leave the Arctic Ocean in an even more vulnerable position with regard to the amount of multi-year ice remaining the following summer.

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North Greenland ice islands

Polar Record ◽

10.1017/s0032247400010809 ◽

1989 ◽

Vol 25 (154) ◽

pp. 207-212 ◽

Cited By ~ 20

Author(s):

A. K. Higgins

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Surface Topography ◽

Ellesmere Island ◽

The Arctic ◽

North Coast ◽

Ice Shelves ◽

The North ◽

The Arctic Ocean ◽

North Greenland

AbstractLarge tabular icebergs derived from the glaciers which drain the north fringe of Greenland's Inland Iceoccur in many North Greenland fjords. Many have undulating surface topography resembling that of the ice islands calved from Ellesmere Island ice shelves. Semi-permanent sea ice in North Greenland fjords often prevents the escape of bergs, except in exceptional summers several decades apart, when the fjord ice melts completely and some bergs may reach the Arctic Ocean. Other possible sources for ice islands are small ice shelves and local glaciers along the north coast of Greenland.

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