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Bering Sea
Wilderness Area |
Site Name
IMPROVE: none
Region
Alaska Maritime (Western Alaska, Bering Sea)
Terrain
Terrain in the area is depicted in detailed 20 km terrain map and 2 km
terrain map
The 81,340-acre Bering Sea Wilderness Area consists of Saint Matthew Island
and the nearby small Hall and Pinnacle Islands, ~ 375 km (233 mi) off the
coast of western Alaska in the Bering Sea. It is in the North Pacific
maritime influence. Topography of the islands is rugged hills and cliffs
interspersed with flat terrain. Elevations range from sea level to cliff top
elevations above 460 m (1,500 ft).
The Bering Sea Wilderness Area is the most isolated Wilderness Area. There
are no nearby representative IMPROVE sites. The nearest maritime IMPROVE
site is the Simeonof IMPROVE site, SIME1, in the Aleutian chain. (Also see
Simeonof Wilderness Area assessment page.)
Representativeness
No IMPROVE site.
Nearby Population/Industrial Centers and Local Sources
There are no major population centers or source regions in this Bering Sea
region. Hooper Bay, the nearest city in Alaska, is ~ 360 km northeast from
Saint Matthew Island. Dust transport from Asia and forest burning on the
Alaska mainland may be the major factors influencing regional visibility
Nearby Meteorological Network Data Stations
This map shows the location of the
nearest air quality and meteorological monitoring sites, with respect to the
Bering Sea Wilderness Area. There are no nearby meteorological network
monitoring sites. The nearest RAWS site is at Reindeer River Alaska,
established in August 1993. The closest and most representative long-term
NWS meteorological monitoring station is at St Paul Island Alaska, 365 km
south-southeast from the Wilderness in the Pribilof Islands of the Bering
Sea. It is also the nearest upper air sounding site. Historical data for
this and other regional first order NWS stations are available via the
EPA Technology Transfer
Network website.
Wind Patterns
The Bering Sea Wilderness is within the global circulation zone of
midlatitude westerlies. Synoptic wind patterns of the Bering Sea are
modified by the Pacific High Pressure Center in the summer and by the
Aleutian Low in the winter. At times, especially in the spring, the Pacific
High over the eastern Pacific Ocean intensifies and creates a ridge that
diverts midlatitude westerly flow from Asia northwards towards Alaska. This
can result in transport of Asian dust to the region. Towards the end of
summer, this ridge weakens and midlatitude flow becomes more zonal
(westerly). Monthly St
Paul Island Alaska wind roses show monthly and seasonal wind patterns at
that southern Bering Sea island location. Wind speeds are generally strong
and wind directions predominantly northerly to easterly in the winter. A
wide range of southerly flow is dominant in the summer.
Inversions/Trapping
At times the marine boundary layer inversion may have potential for trapping
aerosols at low elevations locally, although there are no significant local
sources for particulate matter. Foggy days are common. Subsidence inversion
and stagnation and concurrent aerosol buildup could occur during periods of
persistent regional high pressure in the summer, and when southward spread
of polar air drops temperatures and is conducive to such conditions. This is
less likely to occur during winter periods when the Aleutian Low centered
over the Aleutian Islands to the south is strongest.
Climatological Statistics
St. Paul Island
Alaska Normals Means and Extremes are representative of maritime
locations in the Bering Sea. Other
Alaska Climate
Summaries are available from the
Western Regional Climate Center.
Meteorological Indicators
Keywords
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Last updated 22 September 2004
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