Method for predicting the ice cover parameters in the waters of the Far-Eastern Seas with a long lead time

2018 ◽  
Vol 194 ◽  
pp. 239-250 ◽  
Author(s):  
G. I. Anzhina ◽  
A. N. Vrazhkin
Keyword(s):  
Sea Ice ◽  
Lead Time ◽  
Japan Sea ◽  
Ice Cover ◽  
New Method ◽  
Average Accuracy ◽  
Ice Edge ◽  
Long Term Forecasting ◽  
Far Eastern ◽  
Far Eastern Seas

New method for long-term forecasting of mean month and mean 10-days values of the ice cover and position of the ice edge in the Far-Eastern Seas is presented. The sea ice regime is formed under influence of thermal and dynamic patterns in the atmosphere and hydrosphere, though mechanisms of its forming and evolution are not yet completely clear, so the sea ice forecasting is based mainly on statistical methods. The new method is developed for the ice parameters prediction for the period with stable ice cover. It uses a physical-statistical model with ensemble approach. The minimum lead time of this method is 7 months. The model assimilates the data on absolute topography of 500 GPa surface, atmospheric pressure at the sea level, air temperature at 850 GPa surface and at the sea surface, relative topography of 500/1000 GPa surfaces, and the South Oscillation index. Archives of these fields for the Northern Hemisphere from 1961 to 2017 are loaded. The ensemble of predictions is formed using the criterion of their maximum accuracy on independent data sets. The method is tested for the winter seasons of 2015/2016 and 2016/2017. The most accurate by 3 parameters are the forecasts for the Okhotsk Sea with the average accuracy 75–83 % that is much better than the accuracy of climatic forecasts (61–67 %). The forecast of the mean month ice cover only is satisfactory for the Japan Sea, and the forecast of the ice edge position only (65 % accuracy) exceeds the climate forecasting accuracy for the Bering Sea, while the climatic forecasting shows better results for the ice cover. The average accuracy of forecasting with new method (all parameters for all seas) exceeds 70 %, that allows to recommend the method for practical using. A prognostic product could be proposed as charts of the sea ice edge for future winter with estimations of the ice cover for each sea by months and 10-days.

scholarly journals CYCLONES OVER THE PACIFIC OCEAN AND FAR-EASTERN SEAS IN COLD AND WARM SEASONS AND THEIR INFLUENCE ON WIND AND THERMAL REGIME IN THE LAST TWO DECADE PERIOD

2018 ◽  
Vol 193 ◽  
pp. 153-166 ◽  
Author(s):  
S. Yu. Glebova
Keyword(s):  
Warm Season ◽  
Japan Sea ◽  
Ice Cover ◽  
Asia Pacific ◽  
Cyclonic Activity ◽  
The North ◽  
The Pacific ◽  
Lowered Pressure ◽  
Far Eastern ◽  
Far Eastern Seas

Cyclonic activity in the Asia-Pacific region is largely determined by state of the seasonal centers of atmosphere action. In turn, cyclones themselves influence on conditions in certain «key» areas. Recently the Aleutian Low activity declines in fall-winter and this center is shifted westward, but activity of the Hawaiian High increases in warm season. As the result, heightened air pressure prevails over the Ocean (positive anomalies of the sea level pressure) and lowered pressure (negative anomalies) — over the Far Eastern Seas. In this anomalous situation, the number of cyclones over the Ocean has increased but they become weaker that causes SST increasing in the North Pacific both in winter and summer. Over the Bering Sea, the cyclones become weaker, as well, but this regime causes the ice cover increasing, so SST decreasing in spring. On the contrary, over the Okhotsk Sea and Kuril Islands area, the number of cyclones has decreased gradually but they become stronger in both seasons that causes the ice cover reducing and spring SST rising. In the Japan Sea, cyclonic activity has intensified, too, but this tendency causes cooling in winter and warming in summer.

scholarly journals Holocene variability in sea ice and primary productivity in the northeastern Baffin Bay

arktos ◽  
2020 ◽  
Vol 6 (1-3) ◽  
pp. 55-73 ◽  
Author(s):  
Jeetendra Saini ◽  
Ruediger Stein ◽  
Kirsten Fahl ◽  
Jens Weiser ◽  
Dierk Hebbeln ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ocean Circulation ◽  
Water Discharge ◽  
Greenland Ice Sheet ◽  
Open Water ◽  
Ice Cover ◽  
Arctic Sea Ice ◽  
Baffin Bay ◽  
Arctic Sea ◽  
Ice Edge

AbstractArctic sea ice is a critical component of the climate system, known to influence ocean circulation, earth’s albedo, and ocean–atmosphere heat and gas exchange. Current developments in the use of IP25 (a sea ice proxy with 25 carbon atoms only synthesized by Arctic sea ice diatoms) have proven it to be a suitable proxy for paleo-sea ice reconstructions over hundreds of thousands to even millions of years. In the NE Baffin Bay, off NW Greenland, Melville Bugt is a climate-sensitive region characterized by strong seasonal sea ice variability and strong melt-water discharge from the Greenland Ice Sheet (GIS). Here, we present a centennial-scale resolution Holocene sea ice record, based on IP25 and open-water phytoplankton biomarkers (brassicasterol, dinosterol and HBI III) using core GeoB19927-3 (73° 35.26′ N, 58° 05.66′ W). Seasonal to ice-edge conditions near the core site are documented for most of the Holocene period with some significant variability. In the lower-most part, a cold interval characterized by extensive sea ice cover and very low local productivity is succeeded by an interval (~ 9.4–8.5 ka BP) with reduced sea ice cover, enhanced GIS spring melting, and strong influence of the West Greenland Current (WGC). From ~ 8.5 until ~ 7.8 ka BP, a cooling event is recorded by ice algae and phytoplankton biomarkers. They indicate an extended sea ice cover, possibly related to the opening of Nares Strait, which may have led to an increased influx of Polar Water into NE-Baffin Bay. The interval between ~ 7.8 and ~ 3.0 ka BP is characterized by generally reduced sea ice cover with millennial-scale variability of the (late winter/early spring) ice-edge limit, increased open-water conditions (polynya type), and a dominant WGC carrying warm waters at least as far as the Melville Bugt area. During the last ~ 3.0 ka BP, our biomarker records do not reflect the late Holocene ‘Neoglacial cooling’ observed elsewhere in the Northern Hemisphere, possibly due to the persistent influence of the WGC and interactions with the adjacent fjords. Peaks in HBI III at about ~ 2.1 and ~ 1.3 ka BP, interpreted as persistent ice-edge situations, might correlate with the Roman Warm Period (RWP) and Medieval Climate Anomaly (MCA), respectively, in-phase with the North Atlantic Oscillation (NAO) mode. When integrated with marine and terrestrial records from other circum-Baffin Bay areas (Disko Bay, the Canadian Arctic, the Labrador Sea), the Melville Bugt biomarker records point to close ties with high Arctic and Northern Hemispheric climate conditions, driven by solar and oceanic circulation forcings.

scholarly journals Evaluating seasonal sea-ice cover over the Southern Ocean from the Last Glacial Maximum

2020 ◽  
Author(s):  
Ryan A. Green ◽  
Laurie Menviel ◽  
Katrin J. Meissner ◽  
Xavier Crosta
Keyword(s):  
Southern Ocean ◽  
Sea Ice ◽  
Last Glacial Maximum ◽  
Austral Summer ◽  
Ice Cover ◽  
Proxy Records ◽  
Ice Edge ◽  
Sea Ice Edge ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Abstract. Sea-ice cover over the Southern Ocean responds to and impacts Southern Ocean dynamics and, thus, mid to high latitude climate in the Southern Hemisphere. In addition, sea-ice cover can significantly modulate the carbon exchange between the atmosphere and the ocean. As climate models are the only tool available to project future climate changes, it is important to assess their performance in simulating past changes. The Last Glacial Maximum (LGM, ∼21,000 years ago) represents an interesting target as it is a relatively well documented period with climatic conditions and a carbon cycle very different from pre-industrial conditions. Here, we study the changes in seasonal Antarctic sea-ice cover as simulated in numerical PMIP3 and LOVECLIM simulations of the LGM, and their relationship with windstress and ocean temperature. Simulations and paleo-proxy records suggest a fairly well constrained glacial winter sea-ice edge at 51.5° S (1 sigma range: 50°–55.5° S). Simulated glacial summer sea-ice cover however differs widely between models, ranging from almost no sea ice to a sea-ice edge reaching 55.5° S. The austral summer multi-model mean sea-ice edge lies at ∼60.5° S (1 sigma range: 57.5°–70.5° S). Given the lack of strong constraints on the summer sea-ice edge based on sea-ice proxy records, we extend our model-data comparison to summer sea-surface temperature. Our analysis suggests that the multi-model mean summer sea ice provides a reasonable, albeit upper end, estimate of the austral summer sea-ice edge allowing us to conclude that the multi-model mean of austral summer and winter sea-ice cover seem to provide good estimates of LGM conditions. Using these best estimates, we find that there was a larger sea-ice seasonality during the LGM compared to the present day.

Information-reference system “regime and variability of the ice cover state of the Far Eastern seas”

2010 ◽  
Vol 35 (5) ◽  
pp. 341-343
Author(s):  
I. D. Rostov ◽  
V. V. Plotnikov ◽  
V. I. Rostov ◽  
N. M. Vakul’skaya
Keyword(s):  
Reference System ◽  
Ice Cover ◽  
Far Eastern ◽  
Far Eastern Seas ◽  
Information Reference

scholarly journals Nematodes of common Hexagrammidae species from the Far-Eastern Seas of Russia

2014 ◽  
Vol 176 (1) ◽  
pp. 216-224
Author(s):  
Galina F. Solovyeva ◽  
Zoya I. Motora
Keyword(s):  
Japan Sea ◽  
Anisakis Simplex ◽  
The North ◽  
Pseudoterranova Decipiens ◽  
The Japan Sea ◽  
Pleurogrammus Azonus ◽  
Contracaecum Osculatum ◽  
Far Eastern ◽  
First Time ◽  
Far Eastern Seas

Nematoda parasites of five greenling species from the Far-Eastern Seas ( Pleurogrammus azonus , P . monopterygius , Hexagrammos octogrammus , H . lagocephalus , H . stelleri ) are investigated. The family Hexagrammidae is endemic for the North Pacific. In total, 10 species of nematodes are found: Anisakis simplex l., Pseudoterranova decipiens l., Hysterothylacium aduncum , Contracaecum osculatum l., Ascarophis filiformis , A. curvicauda , A. pacifica , Cucullanellus minutus , Cucullanus heterochrous , and Paracapillaria helenae , all of them have wide geographical and hosts distribution. Anisakis simplex l. and Pseudoterranova decipiens l. are the most common for all investigated host species. The highest species diversity of nematodes (7 species) is registered for arabesque greenling P. azonus , particularly its females; Contracaecum osculatum l. and Cucullanus heterochrous are found for the first time for this host in the Japan Sea. The parasites are dispersed irregularly in muscles of all parts of fish body. Large-sized (i.e. elder) fish is higher infected by larvae of P. decipiens .

scholarly journals Some aspects of biogeography with reference to zoning of the Far- Eastern Seas of Russia and adjacent waters of the Pacific Ocean

2015 ◽  
Vol 183 (4) ◽  
pp. 3-26
Author(s):  
Oleg A. Ivanov ◽  
Vitaly V. Sukhanov
Keyword(s):  
Climatic Factors ◽  
Japan Sea ◽  
Pacific Waters ◽  
The Pacific ◽  
History Of ◽  
The Pacific Ocean ◽  
Far Eastern ◽  
Far Eastern Seas ◽  
Latitudinal Zoning ◽  
Epipelagic Layer

Formation of biogeography, its methodological features, and its status as interdisciplinary science combining biological and geographical aspects are discussed. There is noted that the descriptive period of biogeography has passed, and now any «manifestation of life on the globe» requires its explanation. These explanations are reduced to three non-adversarial restrictions: environmental (ecology), temporal (history of origin, evolution), and spatial (geography). General regularities of life distribution over the Earth surface are analyzed, in particular the features of pelagic organisms habitat, and the concept of «dynamic biogeography» is discussed. Latitudinal zoning of epi- and mesopelagic layers in the Far-Eastern Seas of Russia and adjacent Pacific waters is proposed on the basis of data about areas and distribution of 493 species of nekton (fishes and squids) for the 30-year period (1980-2009) obtained from 27 thousand trawl samples caught in 272 expeditions. This zoning uses a new approach related to the chorological direction in marine biogeography realized with the index of latitudinal zoning (ILZ). For this index calculation, all types of species areas (formerly expressed in verbal forms) were identified with numerical codes, which were averaged for all species in each sample, then the regions with certain ILZ values and borders between them were determined on the maps of ILZ distribution, and latitudinal zones and subzones were defined. There is found that the epipelagic layer of the Okhotsk and Bering Seas corresponds to the high-boreal latitudinal subzone and the epipelagic layer of the northwestern Japan Sea and the major part of Russian EEZ in the Pacific corresponds to the low-boreal latitudinal subzone. Fauna of nekton in the mesopelagic layer of all studied regions corresponds by its chorological structure to the low-boreal latitudinal subzone. So, zoning of epipelagic and mezopelagic layers is significantly different, with the fragmentation reducing with depth, possibly due to weakening of climatic factors influence. The biogeographical zoning is not literally zonal but corresponds to structure of the environments (water masses, fronts, currents, gyres, eddies, etc.).

scholarly journals Southern Ocean Biogeochemical Argo detect under-ice phytoplankton growth before sea ice retreat

2021 ◽  
Vol 18 (1) ◽  
pp. 25-38
Author(s):  
Mark Hague ◽  
Marcello Vichi
Keyword(s):  
Southern Ocean ◽  
Sea Ice ◽  
Light Adaptation ◽  
Ice Cover ◽  
Data Sampling ◽  
Argo Data ◽  
Ice Melt ◽  
Antarctic Sea Ice ◽  
Ice Retreat ◽  
Ice Edge

Abstract. The seasonality of sea ice in the Southern Ocean has profound effects on the life cycle (phenology) of phytoplankton residing under the ice. The current literature investigating this relationship is primarily based on remote sensing, which often lacks data for half of the year or more. One prominent hypothesis holds that, following ice retreat in spring, buoyant meltwaters enhance available irradiance, triggering a bloom which follows the ice edge. However, an analysis of Biogeochemical Argo (BGC-Argo) data sampling under Antarctic sea ice suggests that this is not necessarily the case. Rather than precipitating rapid accumulation, we show that meltwaters enhance growth in an already highly active phytoplankton population. Blooms observed in the wake of the receding ice edge can then be understood as the emergence of a growth process that started earlier under sea ice. Indeed, we estimate that growth initiation occurs, on average, 4–5 weeks before ice retreat, typically starting in August and September. Novel techniques using on-board data to detect the timing of ice melt were used. Furthermore, such growth is shown to occur under conditions of substantial ice cover (>90 % satellite ice concentration) and deep mixed layers (>100 m), conditions previously thought to be inimical to growth. This led to the development of several box model experiments (with varying vertical depth) in which we sought to investigate the mechanisms responsible for such early growth. The results of these experiments suggest that a combination of higher light transfer (penetration) through sea ice cover and extreme low light adaptation by phytoplankton can account for the observed phenology.

scholarly journals Edge displacement scores

2021 ◽  
Author(s):  
Arne Melsom
Keyword(s):  
Sea Ice ◽  
Geographic Location ◽  
Ice Cover ◽  
The Arctic ◽  
Polar Regions ◽  
Ice Edge ◽  
Sea Ice Edge ◽  
Edge Displacement ◽  
Thermodynamic Processes

Abstract. As a consequence of a diminishing sea ice cover in the Arctic, activity is on the rise. The position of the sea ice edge, which is generally taken to define the extent of the ice cover, changes in response to dynamic and thermodynamic processes. Forecasts for sea ice expansion due to an advancing ice edge will provide information that can be of significance for operations in polar regions. However, the value of this information depends on the quality of the forecasts. Here, we present methods for examining the quality of forecasted sea ice expansion and the geographic location where the largest expansion are expected from the forecast results. The algorithm is simple to implement, and an examination of two years of model results and accompanying observations demonstrates the usefulness of the analysis.

Can Antarctic sea-ice extent be determined from whaling records?

Polar Record ◽  
2000 ◽  
Vol 36 (199) ◽  
pp. 345-347 ◽  
Author(s):  
Stephen Vaughan
Keyword(s):  
Sea Ice ◽  
Accurate Method ◽  
Reliable Information ◽  
New Method ◽  
Sea Ice Extent ◽  
Antarctic Sea Ice ◽  
The Subject ◽  
Ice Edge ◽  
Sea Ice Edge ◽  
Sighting Data

SummeryThe subject of retreating global sea-ice extent is a matter of grave concern, and any new method that promises reliable information about past ice-extent parameters must be welcomed. However, the method proposed by De la Mare should be viewed with caution for four reasons. First, his predictions of sea-ice extent do not correspond with known observations of sea-ice extent from research published in 1936 and 1972. Second, his predictions correlate much more closely with the whale-sighting data recorded by Hansen (1936). Third, since Hansen's sea-ice extent data do not correspond closely with his whalesighting data, it must be questioned whether whale-based data should be used for retrospective predictions relating to sea-ice extent. And finally, information from the IWC indicates that De la Mare's datasets are not considered accurate. Predicting sea-ice edge extent is complex, and, it would seem, a purely biological approach is not necessarily the most accurate method to adopt.

Sign in / Sign up

Export Citation Format

Share Document