Northern Hemisphere Ice Charts, GIS, Metadata, and Coverage Files Click on the region above for the most current
color chart or click on the dropdown menu
++To
improve the visual quality of our weekly analysis, our files are now
produced in PDF Format. Please contact NIC Liaison if
you have any questions.++
Due
to varying system properties, please consult your imaging
software manual for printing instructions.
During the first week of September 1996,
the National Ice Center (NIC) began routinely producing regional-scale
analyses for all sea ice covered seas located (clockwise) between
the longitudes of 95E and 95W in the northern hemisphere. This global
area,
known as the "Arctic" to the NIC, is comprised of different
Arctic regions. Analyses of current ice conditions are produced bimonthly
for regions in which sea ice is present. Regions containing no analysis
information should be considered ice-free. Exceptions to this rule
may occur when ice is limited to but does not extend beyond an overlap
between two regions.
All NIC regional sea ice analyses are derived from the near real-time
integration of remotely sensed and in-situ oceanographic/meteorological
observations. These analyses are produced following standard analysis
procedures which optimize the use of data that vary widely in availability,
scale, and resolution. These operational data sources can be grouped
into the following categories: satellite derived data, aerial ice reconnaissance,
ship/shore station observations, drifting buoy reports, meteorological
guidance products, ice prediction model output, climatology and sea ice
information obtained from international partners such as foreign ice
services. Documentation recording the percentages of each data type used
in each analysis can be found in a weekly metada narrative.
NIC analysis and forecast guidance products are produced
on global, regional and tactical scales. These products are disseminated
through a variety of communications paths in both digital and analog
formats.
Digital products include:
Global sea ice edge products consisting of latitude/longitude pairs.
Sea ice analysis charts in Graphics Interface Format (*.gif) which
can be viewed with almost any web browser and/or graphics viewer .
Geographic Information System (GIS) ARC/INFO coverages.
GIF charts are labeled using the World
Meteorological Organization (WMO) international sea ice symbology
known colloquially as the "Egg
Code". ARC/INFO coverages are produced in Polar Stereographic
projection with the standard parallel at 60N. All ARC/INFO sea ice
attribute information are coded in a modified text strings derived
from the WMO digital sea ice standard known as SIGRID.
All NIC digital ice products use this attribute standard to describe
analyzed sea ice parameters. This system also provides users
with ice forecast products which are not available via the NIC web
page. The West
Arctic 30-day forecast is completed by the first Friday of each
month. A seasonal West Arctic (90 day) forecast for the coastal shipping
lane along the north slope of Alaska is available on 1 June of each
year. This system also provides users with ice forecast products which
are not available via the NIC web page. The East Arctic 30-day forecast
is completed by the first Friday of each month. A seasonal East
Arctic (90 day) forecast for the Thule Greenland resupply is available
on 1 June of each year.
Users are encouraged to submit suggestions, recommendations, and questions
to the National
Ice Center Liaison.
Home Page last updated on
September 12, 2008