| |
Lostwood Wilderness Area |
(Also see
Theodore Roosevelt National Park Meteorological Description Page)
Site Name
IMPROVE:
LOST1
Region
Northern Great
Plains
Terrain
The Lostwood Wilderness consists of 5,577 acres within the 26,747-acre
Lostwood National Wildlife Refuge in Northwestern North Dakota, 40 km (25
mi) south of the Canadian border. Terrain of the region is primarily rolling
hills and wetlands of the Missouri Coteau, also known as the Coteau Prairie,
an expanse of upland between the upper Missouri River to the south and west
and the glaciated plains of central North Dakota and the Canadian Prairie
Provinces. Elevations are typically 700 – 750 m (2,300 – 2,500 ft). Terrain
in the area is depicted in detailed 20 km terrain map and 2 km terrain map.
The IMPROVE site representing Lostwood Wilderness is LOST1, elevation 692 m
(2270 ft), located in the northernmost portion of the Wildlife Refuge. The
nearest CASTNET site is THR422,
located in the Theodore Roosevelt National Park some 130 km (80 mi)
south-southwest of LOST1.
Representativeness
LOST1 is well exposed to regional scale transport flow and aerosol data
collected there should be very representative of visibility in and around
the Lostwood Wilderness.
Nearby Population/Industrial Centers and Local Sources
Population is sparse in the vicinity of the monitoring site. The nearest
large community is Minot, population ~37,000, 100 km (62 mi) to the
east-southeast. Bismarck is 240 km (150 mi) southeast, population 95,000.
Major point sources in the area include a group of coal-fired power plants
in west-central North Dakota, ~ 200 km (125 mi) southeast. A 2003 EPA
modeling study indicated that SO2 emissions from these and other sources may
impact the Lostwood Wilderness and three other Class I areas in the region
(EPA, 2003). SO2 is a predecessor to light scattering secondary
particulates. The area around Lostwood Wilderness is largely prairie, and
there may be periodic emissions from prescribed burns or from wildland fires
during hot and dry periods.
Nearby Data Stations
This map shows the location of the nearest air quality and meteorological
monitoring sites with respect to the Lostwood Wilderness monitoring site
LOST1. The
Lostwood RAWS site where monitoring commenced in August 2002 is nearby.
The CASTNET site THR422, Theodore
Roosevelt National Park, is 130 km (80 mi) south-southwest. Because of the
relatively simple intervening terrain meteorological data from this site
should be reasonably representative of Lostwood Wilderness. These data are
available at Theodore Roosevelt
CASTNET website.
The nearest upper air site is the Bismarck RAOB site, where atmospheric
soundings are conducted twice daily. Data from the Bismarck site should be
the best available representation of vertical atmospheric structure at LOST1
and the Lostwood Wilderness.
Wind Patterns
The LOST1 monitoring site is well exposed to prevailing synoptic wind
patterns due to the gentle topography of the region. Winter is characterized
by frequent outbreaks of cold continental air from the Canadian interior.
Visibility improves following passage of these relatively clean continental
airmasses. During the rest of the year the migration of the jet stream to
more northerly latitudes results in more frequent transport of warmer moist
air from the Gulf of Mexico and warm dry air from the southwestern U.S. Long
term (1961-2002) wind patterns are shown in Bismarck wind roses (wind roses
archived by DRI). Wind directions in the area are a consequence of the
synoptic pattern and are predominantly southeasterly and northwesterly.
Southerly to easterly flow is frequent during the summertime.
Inversions/Trapping
Surface inversions over this prairie terrain are typically shallow and
easily dispersed by ambient winds, hence not as likely to trap or accumulate
pollutants over prolonged periods. Of more significance with respect to
visibility in the Lostwood Wilderness, large scale elevated subsidence
inversions associated with persistent regional high pressure may cause
aerosol buildup and regional haze. These can result in higher measured
aerosol concentrations at the site, especially in the warmer months, and can
persist for periods of days until ventilation occurs in conjunction with
frontal passages or onset of stormy low-pressure systems.
Climatological Statistics
Climatological data available from the Theodore Roosevelt NP
CASTNET site, THR422, should be
representative of the Lostwood Wilderness. Longer term
Bismarck North Dakota
Climate data are also regionally representative.
Meteorological Indicators
Keywords
References
EPA, 2003. Dispersion Modeling Analysis of PSD Class I Increment Consumption
in North Dakota and Eastern Montana. U.S. Environmental Protection Agency
Region 8 Air and Radiation Program, 999 18th St, Suite 300, Denver, CO
80202. May, 2003.
|
Last updated 10 December 2004
|