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Jarbidge Wilderness Area |
Site Name
IMPROVE: JARB1
Region
Columbia Plateau, Great Basin
Terrain
Terrain is shown in the 2 km terrain map and the 20 km terrain map.
The Jarbidge Wilderness Area comprises 113, 167 acres in extreme northern
Nevada, near the Idaho border and just north of the physiographic boundary
separating the Columbia Plateau region and the Great Basin region to the south.
It consists of the headwaters basin of the Jarbidge River East Fork that flows
north from the center of the Wilderness, and the headwaters basin of Marys River
that flows south from the center of the Wilderness, part of the Columbia
River/Great Basin hydrographic divide. Wilderness elevations range from near
2,100 m (6,900 ft) where the Jarbidge River East Fork exits the wilderness, to
3,170 m (10,398 ft) at the summit of Marys River Peak. Terrain is deep canyons
with steep slopes.
The IMPROVE site representing Jarbidge Wilderness is JARB1, located in the
Jarbidge River Canyon near the town of Jarbidge and outside and west of the
nearest Wilderness boundary. The site is on a bench about 50 m (150 ft) above
river level. Its elevation is 1,882 m (6,173 ft). The Jarbidge River Canyon,
which comprises the upper main headwaters of the Jarbidge River proper, is
oriented south to north, with its mouth several miles to the north where it
drains into the Bruneau River. Elevations near the monitoring site rise from
river level near the monitoring site to some 300 to 400 m (1200 to 1300 ft)
higher at a distance of ~ 1 mile to the west, and to 500 to 600 m (1500 to 2000
ft) higher at distance of 2 to 3 km (1 to 1.5) miles east at the western
Wilderness Area boundary. To the north some 5 km (3 mi), the canyon narrows even
further to a constriction about 1 to 2 km wide and ~ 400 m (1200 to 1300 ft)
from rim to river
Representativeness
Generally, JARB1 should be representative of aerosol characteristics in the
Jarbidge Wilderness, especially when the atmosphere is well mixed and regionally
homogeneous. The site is at a low elevation in the Jarbidge River Canyon that is
separate from the Jarbidge Wilderness Area and upper East Fork of the Jarbidge
River. Consequently, it may at times be within a trapping canyon inversion that
isolates it from Wilderness locations and that is potentially impacted by
different local emission sources.
Nearby Population/Industrial Centers and Local Sources
The Jarbidge Wilderness and JARB1 monitoring site are quite distant and isolated
from major sources and source regions. Local sources could include smoke from
forest fires. Highest aerosol concentrations may occur during regional wildfire
episodes during periods of stagnation.
Nearby Meteorological Data Stations
Nearby meteorological monitoring network stations are shown in the data network
map and at the
RAWS station US Climate Archive
site. The Jarbidge
West Fork WQ Nevada RAWS site is very close to JARB1 but has a short period
of record beginning in 2002. The
Stag Mountain Nevada
RAWS site is located 40 km south of JARB1 and 16 km south of the southern
Wilderness boundary, elevation 2,070 m (6,790 ft), and should also provide data
representative of regional conditions concurrent with aerosol monitoring at
JARB1.
Nearest routine upper air data collection sites are the Elko (LKN) RAOB site 125
km (80 mi) south and the Boise (BOI) RAOB site 200 km (120 mi) north of JARB1.
Wind and Transport Patterns
The Jarbidge Wilderness Area is located at the northern edge of the Great Basin
physiographic region. Synoptic winds in the area are generally westerly, with a
significant wintertime easterly component. Regional wind patterns are indicated
in monthly Elko Nevada Wind Roses.
Locally, wind directions at the JARB1 monitoring site may be channeled to a
north/south direction. In absence of synoptic forcing, local wind patterns
should be characteristic of mountain/valley circulation with southerly (from the
south) nighttime drainage flow and northerly daytime upslope flow in the valley.
Inversions/Trapping
The steep Jarbidge Canyon where JARB1 is located is subject to surface based
radiation inversions that can trap pollutants locally, especially in the winter.
The possibility of significant or frequent high aerosol concentrations caused by
local valley trapping inversions is mitigated because of the absence of nearby
emission sources.
The area is subject to largescale subsidence inversion conditions associated
with regional surface high pressure over the Great Basin that can cause buildup
and stagnation of aerosols over periods of days. Highest concentrations may
result when this warming and drying condition leads to major western wildland
fire episodes.
The most likely scenario for buildup of light scattering pollutants at JARB1 may
be smoke from wildland fires, either carried into the area from local fires by
mountain valley circulation, or via transport winds from more distant fires and
regional accumulation during wildfire episodes in summer and fall.
Climatological Statistics
Long term Jarbidge
4N Nevada climate data are representative of JARB1.
Elko Nevada Normals
Means and Extremes are representative of lower elevations in Northern
Nevada. Other Nevada
Climate Summaries and
Idaho Climate Summaries
are available from the Western Regional
Climate Center.
Keywords
Valley
Inversion
Channeling
Mountain/valley circulation
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