Observations of frazil ice formation and upward sediment transport in the Sea of Okhotsk: A possible mechanism of iron supply to sea ice

2017 ◽  
Vol 122 (2) ◽  
pp. 788-802 ◽  
Author(s):  
Masato Ito ◽  
Kay I. Ohshima ◽  
Yasushi Fukamachi ◽  
Genta Mizuta ◽  
Yoshimu Kusumoto ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Sea Ice ◽  
Sea Of Okhotsk ◽  
Ice Formation ◽  
The Sea Of Okhotsk ◽  
Frazil Ice ◽  
Iron Supply

Underwater frazil ice and its suspension depth detected from ADCP backscatter data around sea ice edge in the Sea of Okhotsk

2021 ◽  
pp. 103382
Author(s):  
Masato Ito ◽  
Kay I. Ohshima ◽  
Yasushi Fukamachi ◽  
Genta Mizuta ◽  
Yoshimu Kusumoto ◽  
...  
Keyword(s):  
Sea Ice ◽  
Sea Of Okhotsk ◽  
The Sea Of Okhotsk ◽  
Frazil Ice ◽  
Ice Edge ◽  
Sea Ice Edge

Seasonal variations in the properties and structural composition of sea ice and snow cover in the Bellingshausen and Amundsen Seas, Antarctica

1997 ◽  
Vol 43 (143) ◽  
pp. 138-151 ◽  
Author(s):  
M. O. Jeffries ◽  
K. Morris ◽  
W.F. Weeks ◽  
A. P. Worby
Keyword(s):  
Sea Ice ◽  
Isotopic Composition ◽  
Snow Cover ◽  
Sea Water ◽  
Ice Cores ◽  
Ice Cover ◽  
Snow Accumulation ◽  
Ice Formation ◽  
Frazil Ice ◽  
Core Sets

AbstractSixty-three ice cores were collected in the Bellingshausen and Amundsen Seas in August and September 1993 during a cruise of the R.V. Nathaniel B. Palmer. The structure and stable-isotopic composition (18O/16O) of the cores were investigated in order to understand the growth conditions and to identify the key growth processes, particularly the contribution of snow to sea-ice formation. The structure and isotopic composition of a set of 12 cores that was collected for the same purpose in the Bellingshausen Sea in March 1992 are reassessed. Frazil ice and congelation ice contribute 44% and 26%, respectively, to the composition of both the winter and summer ice-core sets, evidence that the relatively calm conditions that favour congelation-ice formation are neither as common nor as prolonged as the more turbulent conditions that favour frazil-ice growth and pancake-ice formation. Both frazil- and congelation-ice layers have an av erage thickness of 0.12 m in winter, evidence that congelation ice and pancake ice thicken primarily by dynamic processes. The thermodynamic development of the ice cover relies heavily on the formation of snow ice at the surface of floes after sea water has flooded the snow cover. Snow-ice layers have a mean thickness of 0.20 and 0.28 m in the winter and summer cores, respectively, and the contribution of snow ice to the winter (24%) and summer (16%) core sets exceeds most quantities that have been reported previously in other Antarctic pack-ice zones. The thickness and quantity of snow ice may be due to a combination of high snow-accumulation rates and snow loads, environmental conditions that favour a warm ice cover in which brine convection between the bottom and top of the ice introduces sea water to the snow/ice interface, and bottom melting losses being compensated by snow-ice formation. Layers of superimposed ice at the top of each of the summer cores make up 4.6% of the ice that was examined and they increase by a factor of 3 the quantity of snow entrained in the ice. The accumulation of superimposed ice is evidence that melting in the snow cover on Antarctic sea-ice floes ran reach an advanced stage and contribute a significant amount of snow to the total ice mass.

Causes and impacts of sea ice variability in the sea of Okhotsk using CESM-LE

2021 ◽  
Author(s):  
Matthew Z. Williams ◽  
Melissa Gervais ◽  
Chris E. Forest
Keyword(s):  
Sea Ice ◽  
Sea Of Okhotsk ◽  
The Sea Of Okhotsk

scholarly journals Sea-ice drift characteristics revealed by measurement of acoustic Doppler current profiler and ice-profiling sonar off Hokkaido in the Sea of Okhotsk

2011 ◽  
Vol 52 (57) ◽  
pp. 1-8 ◽  
Author(s):  
Yasushi Fukamachi ◽  
Kay I. Ohshima ◽  
Yuji Mukai ◽  
Genta Mizuta ◽  
Masaaki Wakatsuchi
Keyword(s):  
Sea Ice ◽  
Sea Of Okhotsk ◽  
Acoustic Doppler Current Profiler ◽  
Ice Thickness ◽  
Coastal Station ◽  
Turning Angle ◽  
The Sea Of Okhotsk ◽  
Ice Drift ◽  
Current Profiler ◽  
Sea Ice Drift

AbstractIn the southwestern part of the Sea of Okhotsk off Hokkaido, sea-ice drift characteristics are investigated using the ice and water velocities obtained from a moored upward-looking acoustic Doppler current profiler (ADCP) during the winters of 1999–2001. Using hourly-mean values of these data along with the wind data measured at a nearby coastal station, the wind factor and turning angle of the relative velocity between the ice and water velocities with respect to the wind are calculated assuming free drift under various conditions. Since the simultaneous sea-ice draft data are also available from a moored ice-profiling sonar (IPS), we examine the dependence of drift characteristics on ice thickness for the first time. As ice thickness increases and wind decreases, the wind factor decreases and the turning angle increases, as predicted by the theory of free drift. This study clearly shows the utility of the moored ADCP measurement for studying sea-ice drift, especially with the simultaneous IPS measurement for ice thickness, which cannot be obtained by other methods.

scholarly journals Evaluation of the representation of Arctic sea ice in the U.K. Hadley Centre GCM

1997 ◽  
Vol 25 ◽  
pp. 423-428
Author(s):  
Douglas M. Smith ◽  
Claire Cooper ◽  
Duncan J. Wingham ◽  
Seymour W. Laxon
Keyword(s):  
Sea Ice ◽  
Sea Of Okhotsk ◽  
Seasonal Cycle ◽  
Arctic Sea Ice ◽  
Surface Energy Budget ◽  
Sea Surface ◽  
Hudson Bay ◽  
The Sea Of Okhotsk ◽  
Arctic Sea ◽  
Hadley Centre

The amount of Arctic sea ice predicted by the Hadley Centre Global Cilimate Model (GCM) is evaluated using 15 years of passive-microwave data. While the Hadley model reproduces the seasonal cycle reasonably well, it underestimates the total area of sea ice by more than 3 × 106km2for most of the year. In the winter months, most of the underestimate in ice area results from the prediction of far too little ice in Hudson Bay and the Sea of Okhotsk, leading to an excess of up to 0.2 PW heat input to the atmosphere from Hudson Bay alone. The surface-energy budget of Hudson Bay is investigated using a mixture of surface observations (POLES), satellite data (ATSR, SSM/I and ISCCP) and output from the Goddard Data Assimilation Office analysis. Flux adjustments of the order of 200 Wm−2, resulting from anomalously high sea-surface temperatures in the Levitus (1982) climatology, are found to be the cause of the model’s underestimation of sea ice in both Hudson Bay and the Sea of Okhotsk. The fact that flux adjustments based on an inaccurate climatology will produce errors, even if the model physics is correct, underlines the need both for improved climatologies and for models accurate enough not to require flux adjustment.

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