Long-term forecasts

April, 07

1. The short review of ice conditions in estuarial areas of the rivers of the Arctic zone of Siberia from October, 2016 to March, 2017.
Process of freezing took place in mouths of the rivers of the Arctic zone of Siberia during the end of September - the beginning of October. Floating ice has been noted in mouths of the rivers of the Kara Sea from October 18 to October 29, the Laptev Sea from September 30 to October 13, the East Siberian Sea from October 13 to October 17.
Estuarial areas of the rivers of the basin of the Kara Sea.
Steady emergence of floating ice has been noted after norm from 3 days (item Igarka) to 17 days (the item of Sopochnaya the Hag). Terms of a freeze-up are noted after norm from 4 days (the item. Guard) to 19 days (the item. Novyi Port). Period duration with floating ice has made of 1 day in the item. Guard and Tazovskoye up to 17 days in the item. New Port.
Ice thickness at the end of December, 2016 were observed more norm in points Dudinka and Igarka on the 8-13th. In points Salekhard, New Port and Tazovskoye - about norm. In points of Sopochnaya the Hag and Guard - are less than norm on 12-37 cm. For the end of March, 2017 of thickness of ice there was following: in points Salekhard, New Port, Dudinka - is more than norm on 8-18 cm, in Tazovskoye's points, Igarka, Guard and Sopochnaya the Hag - is less than norm on 5-36 cm.
Estuarial areas of the rivers of the basin of the Laptev Sea.
In estuarial areas of the rivers of the basin of the Laptev Sea steady emergence of floating ice is noted in the terms close to mean annual, except point Ust-Olenyok where floating ice has appeared for 8 days after norm. The freeze-up is noted after norm from 2 days (the item of Tyumeti) to 8 days (item Ust-Olenyok).
Period duration with floating ice has made 11-15 days, except the item Ust-Olenyok where floating ice was observed within 4 days.
Ice thickness at the end of December, 2016 were observed less norm on 4-27 cm except the item Kyusyur where thickness of ice is noted more norm on 10 cm. For the end of March, 2017 of thickness less norm on 11-47 cm is universal.
Estuarial areas of the rivers of the basin of the East Siberian Sea.
On estuarial sections of the Kolyma Rivers and Indigirka floating ice and a freeze-up have been noted after norm: floating ice for 8-10 days, a freeze-up for 9-13 days. Period duration with floating ice has made 5-6 days. Ice thickness at the end of December, 2016 were observed less norm on 22-24 cm. At the end of March, 2017 - there is less norm on 32-41 cm.

2. The long-term forecast of thickness of ice for the end of April and terms of opening of lower reaches and mouths of the rivers of Siberia for spring of 2017.
Opening of an estuarial part of the large rivers will take place at the end of May – June. In relation to average long-term values terms of opening of ice in estuarial parts of the rivers of basins of the Karsky and East Siberian seas and the Laptev Sea is expected before norm, or close to norm.
Ice thickness for the end of April in east part of the Arctic are predicted less mean annual values. In the western part - it is less also more norm.
Estuarial area of the rivers of the basin of the Kara Sea.
In estuarial areas of the large rivers of the basin of the Kara Sea of ice thickness at the end of April less mean annual values to 32 cm, except points Salekhard, Novyi Port and Dudinka where thickness are expected more norm to 18 cm are expected. The beginning of an ice drift is expected before norm: in an estuarial part of the Ob River for 4 days, in an estuarial part of the Taz River for 8 days, in an estuarial part of the Yenisei River for 3-4 days (except the item Dudinka where the ice drift is expected in the terms meeting standard).
Estuarial area of the rivers of the basin of the Laptev Sea.
In estuarial areas of the large rivers of the basin of the Laptev Sea at the end of April ice thickness less norm to 49 cm are expected. The beginning of an ice drift is expected before norm: in an estuarial part of the Olenyok River for 1-4 days, in an estuarial part of the Lena River for 1-2 days, in an estuarial part of the Yana River for 2 days.
Estuarial area of the rivers of the basin of the East Siberian Sea.
In estuarial sections of the Indigirka Rivers and Kolyma thickness of ice are expected up to 49 cm less norm. The beginning of an ice drift is expected before norm in an estuarial part of the river Kolyma for 1 day. On the Indigirka River the ice drift is expected in the terms meeting standard.

The expected ice thickness for the end of April, 2017.
on lower reaches and estuarial areas of the rivers of Siberia

The expected terms of opening of lower reaches and mouths of the rivers of Siberia in the spring of 2017.


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March, 22

B U L L E T I N

of "Long-term ice forecasts for the Arctic seas on the first half of navigation (June-August), 2017"

The predictive bulletin includes general information about the expected ice conditions in the Russian Arctic seas in the first half of navigation (June-August), 2017. For an assessment of intensity of the expected development of ice conditions, the forecast is compared to mean annual values (the norm calculated from 1970 for 2010).

Kara Sea

The area of the Novozemelsky ice massif in June-August is expected 18-35% less than medium long-term values (fig. 3): the third decade of June – 40%, norm of 75%; the third decade of July – 5%, norm of 34%; the first decade of August – 0%, norm of 18%.

In the first half of navigation in a southwest part of the Kara Sea the ligth type of ice conditions (fig. 4) is expected.

The area of the Severozemelsky ice massif in July-August is expected 28-29% less than medium long-term values (fig. 3): July – 40%, norm of 68%; August – 10%, norm of 39%.

In the first half of navigation in a northeast part of the Kara Sea the ligth type of ice conditions (fig. 4) is expected.

Breaking of solder in a coastal part of Vilkitsky Strait is expected for 10 days before mean annual term – on July 20, norm on July 30.

Laptev Sea

The area of the Taimyr ice massif in July-August is expected 5-11% less than medium long-term values (fig. 3): July – 60%, norm of 71%; August – 38%, norm of 43%.

In the first half of navigation in the western part of the sea the medium type of ice conditions (fig. 4) is expected.

The area of the Yansky ice massif in July-August is expected 10-15% less than medium long-term values (fig. 3): July – 62%, norm of 77%; August – 6%, norm of 16%.

In the first half of navigation in east part of the sea the ligth type of ice conditions (fig. 4) is expected.

Breaking of solder along the coast in the western part of the sea is expected for 5-10 days before medium long-term terms – on July 10, norm on July 17, in east part of the sea for 10 days before medium long-term terms – on July 5, norm – on July 15.

East Siberian Sea

The area of the Novosibirsk ice massif in July-August is expected 10-13% less than medium long-term values (fig. 3): July – 71%, norm of 81%, August – 20%, norm of 33%.

In the first half of navigation in the western part of the sea the ligth type of ice conditions (fig. 4) is expected.

The area of the Aion ice massif in July-August is expected 5% less than medium long-term values (fig. 3): July – 82%, norm of 87%, August – 61%, norm of 66%.

In the first half of navigation in east part of the sea the medium type of ice conditions (fig. 4) is expected.

Breaking of solder in a throat of Chaun Bay (on the site Aion-Valkarkay) is expected for 7 days before medium long-term value – on June 25, norm on July 2.

In the first half of August the central type of provision of solid ices is most probable.

Chukchi Sea

The area of the Vrangelevsky ice massif in July-August is expected 5-7% less than medium long-term values: July – 31% norm of 36%; August – 5%, norm of 12% (fig. 3).

Breaking of solder on the coastal site the cape Yakan – the cape Vankarem is expected for 10 days of earlier medium long-term terms – on June 30, norm on July 10.

In the first half of navigation in a southwest part of the sea the ligth type of ice conditions (fig. 4) is expected.

Thus, in the first half of navigation in the Arctic seas the following prevailing type of ice conditions (fig. 4) is expected:

- ligth – in Barents, Karsky, east part of Laptev, the western part East Siberian and in Chukchi the seas;

- medium – in the western part of Laptev and in east part East Siberian the seas;

- realization of heavy type on water areas of the Arctic seas in the first half of navigation isn't expected.

March 21, 2017.

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FIG. 4