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Tuxedni Wilderness Area |
Site Name
IMPROVE:
TUXE1
Region
Alaska Maritime (Aleutian Range, South-central Alaska)
Terrain
The Tuxedni Wilderness consists of Chisik and Duck Islands that lie along
the northwest edge of Cook Inlet in the south-central climatic region of
Alaska. The Islands are ~ 3 km across the Tuxedni Channel from the Alaska
mainland. This region is subject to the Gulf of Alaska maritime influence.
The Tuxedni Wilderness IMPROVE site (TUXE1) is located near the seashore (1
km west of sea shore) at an elevation of 15 m (~ 49 ft). It is near Johnson
River Valley and ~12 km south of Tuxedni Channel and east of the nearest
high mountain, Iliamna Volcano (3053 m), in the Aleutian Mountain range. The
terrain in the vicinity of TUXE1 is seashore to the east, and mountainous to
the west. Regional ground cover in the mountains is predominantly glacier
ice and snow and at lower elevations is forest.
Terrain in the area is depicted in detailed 20 km terrain map and 2 km
terrain map.
Representativeness
The TUXE1 IMPROVE site is very near to complex terrain but it is exposed to
the east and south towards Tuxedni Wilderness. Aerosol data collected at
TUXE1 should be representative of aerosol concentrations and composition in
the Tuxedni Wilderness and Cook Inlet.
Nearby Population/Industrial Centers and Local Sources
The town of Anchor Point Alaska is about 52 km east-southeast of TUXE1, with
no intervening terrain features. Anchorage, the biggest city in Alaska, is
203 km northeast from TUXE1. Dust transport from Asia and wildfire in this
forested region and the Alaska mainland may also influence visibility at
TUXE1. Aerosol measurements may show high sea salt/sulfate components.
Nearby Meteorological Network Data Stations
This map shows the location of the
nearest air quality and meteorological monitoring sites, with respect to the
TUXE1 IMPROVE site. The closest long-term NWS meteorological monitoring
station is the Homer Alaska NWS office
~ 70 km (43 mi) to the southeast and across Cook Inlet from TUXE1.
Wind Patterns
The Tuxedni Wilderness is within the global circulation zone of midlatitude
westerlies. Regionally prevailing winds are modified in the summer by the
Pacific High Pressure system over the eastern Pacific Ocean and in winter by
the Aleutian Low. At times, especially in the spring, the Pacific High
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). Wind speeds in Cook Inlet are generally
calm. Monthly Kodiak wind roses
from a Gulf of Alaska maritime location ~ 250 km (155 mi) south of TUXE1 are
illustrative of regional patterns, although terrain at this Kodiak Island
eastern shore site may affect wind direction locally, especially for lighter
wind speeds. Wind directions are predominantly from the northwest, with an
easterly component in the summer.
TUXE1 is situated at the end of a glacial valley that opens towards the sea
to the east, and can thus be subject to both mountain valley wind and
land-sea breeze diurnal patterns locally.
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. 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 is strongest.
Climatological Statistics
Homer Alaska
Normals Means and Extremes are representative of the climatology of Cook
Inlet. Other Alaska
Climate Summaries are available from the
Western Regional Climate Center Alaska
climate information is also available from the
Alaska Climate Research Center.
Meteorological Indicators
Keywords
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Last updated 22 September 2004
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