Introduction The accelerated decline of
arctic sea ice in recent years presents both challenges and
opportunities. There will be enhanced fishing, resource
extraction, and marine transportation in the Arctic Ocean
but there also will be challenges for the local Native
subsistence communities who use the ice cover as a hunting
platform. To assist in the planning and management of
economic and subsistence activities in the north polar
regions, it is important to develop capabilities for
seasonal forecasts of arctic sea ice. We plan to improve our
existing seasonal ensemble forecasting system
and use the system to predict sea ice conditions in the
arctic and subarctic seas with lead times ranging from one
month to three seasons. The ensemble
forecasting system is based on a synthesis of
a model, NCEP/NCAR reanalysis data, and satellite observations of
ice concentration. The model is the Pan-Arctic Ice-Ocean Modeling and Assimilation System (PIOMAS, Zhang and
Rothrock, 2003). The ensemble
predictions are constructed by using the NCEP/NCAR atmospheric
forcing from the previous 7 years (corresponding to 7 ensemble
members) and the PIOMAS retrospectively estimated,
with assimilation of satellite ice
concentration data, ice and ocean
conditions at a given date at which ensemble
predictions start. Details about the ensemble prediction procedure
may be found in Zhang
et al., 2008.
The September
2015 arctic sea ice extent is predicted to be 5.2
+/- 0.6 million square kilometers(forecast
starts on 8/1/2015). Movie:
hindcast/forecast of 2014 Arctic sea ice (forecast starts on
8/1/2014) (To view
the movie frame by frame, download it and use the free QuickTime
Player to open it)
Movie: Zooming of the Chukchi and
Beaufort seas (To view
the movie frame by frame, download it and use the free QuickTime
Player to open it)
Movie: Zooming of the Northwest
Passage region (To view
the movie frame by frame, download it and use the free QuickTime
Player to open it)
Ensemble
forecast of 9/2015 ice thickness and standard deviation (SD)
(white line is satellite observed ice edge for
9/2014 and black line is model predicted ice edge for 9/2015)
Comparison
of the NCEP/NCAR surface air temperature (SAT) between 2015 and
2014.
Hindcast of September Arctic sea ice
-- white (black) line is satellite
(model) observed (simulated) ice edge --
Links to some other activities for seasonal outlook
of arctic sea ice
The purpose
of the seasonal predictions of arctic sea ice is for scientific
research and education only. There are many uncertainties with the
predictions and the results must be viewed with caution. The work
is conducted at the Polar Science Center, Applied Physics
Laboratory, University of Washington. Support is provided by NSF.
Neither the Government nor the University of Washington nor any
individual person makes any warranty, expressed or implied, or
assumes any responsibility or liability for the use of the
prediction results or any other results in this web site.