Piedmont National Wildlife Refuge

1
Piedmont National Wildlife Refuge

• January 23, 2004
• Smoke Simulation Analysis
• Gary L. Achtemeier
• USDA Forest Service
• Athens, GA

2
Task Description

• The following set of slides summarize a
  PB-Piedmont post-burn analysis of smoke movement
  in the aftermath of a 585 acre prescribed burn
  conducted by the Piedmont National Wildlife
  Refuge. The burn was conducted on 23 January
  2004. The model simulations run from 1600 EST 23
  January through 0900 EST 24 January.

3
Weather

• Weather during the burn and the post-burn smoke
  movement period was clear and dry. A high
  pressure system to the west of the burn site in
  combination with a strong low well to the
  northeast favored winds blowing initially from
  the northwest. As high settled south of the burn
  site, winds shifted to the southwest and
  diminished during early evening. Then, winds
  increased for the remainder of the simulation.
  The geostrophic wind, a measure of the intensity
  of the synoptic pressure driving the winds, began
  the period at 13.5 m/sec at 1600 LST, diminished
  steadily to 8.6 m/sec at 2000 LST, and increased
  to 18.9 m/sec by the end of the simulation
  period. This was a case of strong synoptic
  dominance.

4
Modeling Information

• PB-Piedmont Version 3.0-2003
• Grid spacing 60m
• Domain size 296x406 -gt 17.8x24.4 km
• Visual domain 10.4x9.3 km
• Weather data Hourly METAR
• Elevation data USGS 30 m DEM

5
Modeling Information
The next slide shows the PB-Piedmont viewing
domain for the 23 January 2004 smoke simulation.
The model burn area is shown by the blue square.
The actual burn area is outlined by the white
polygon. Smoke observations taken between
2200-2400 LST and again at 0900 LST by Fish
Wildlife Service personnel are located by the red
circles. The model smoke plume at 1700 LST for
the 10 m surface layer is shown by the yellow
dots.
6
PB-Piedmont domain, roads, observation points
1700 LST 23 January 2004
PB-Piedmont smoke pattern at 1700 LST. Already
the wind is shifting to blow from the southwest.
Numbered red circles locate smoke observation
sites to be discussed in slides to follow.
1
4
2
3
7
PB-Piedmont domain, roads, observation points
1800 LST 23 January 2004
By 1800 LST, winds shifting to the southwest blew
smoke over two of the smoke observation sites.
8
PB-Piedmont domain, roads, observation points
2000 LST 23 January 2004
Drainage forcing has concentrated smoke in small
side valleys downwind from the burn site.
Meanwhile, a drainage flow has overcome the
synoptic forcing and is pushing smoke down the
Falling Creek valley south of the burn site.
9
PB-Piedmont domain, roads, observation points
2300 LST 23 January 2004
The model turns winds too far to blow from the
south rather than the southwest. No smoke was
reported at Falling Creek Bridge (1). Heavy smoke
was reported at the entrance to Wildlife Drive
(2). Heavy smoke was reported at the exit to
Wildlife Drive (3). Moderate smoke was reported
at the shops (4).
4
1
2
3
10
PB-Piedmont domain, roads, observation points
0800 LST 24 January 2004
By 0800 LST, Light smoke was still seen across
the Falling Creek Bridge (1), smoke was at the
Wildlife Drive entrance (2) and exit (3), and no
smoke was at the Refuge shop (4).
4
1
2
3
11
PB-Piedmont domain, roads, observation points
0900 LST 24 January 2004
By 0900 LST, warming during the morning coupled
the model drainages flows with synoptic forcing
to turn the winds to blow from the southwest.
This blew smoke away from Falling Creek and the
Wildlife Drive entrance toward the exit, and the
Refuge shop.
4
1
2
3
12
Summary
Smoke observations were taken between 2200-2400
LST 23 January and at 0920 LST 24 January 2004.
The evening smoke observations were compared with
PB-Piedmont simulated smoke at 2300 LST.

• PB-Piedmont placed the west edge of the smoke
  near or at the Falling Creek bridge (1). No smoke
  was observed there.
• PB-Piedmont placed dense smoke across the
  intersection of Juliette Rd and Wildlife Dr
  entrance (2). Dense smoke was observed there.
• PB-Piedmont moved smoke up drainages just west of
  the intersection of the intersection of Juliette
  Rd and Wildlife Dr exit (3) but placed no smoke
  at the intersection. Dense smoke was observed at
  the intersection.
• PB-Piedmont placed scattered smoke in the
  vicinity of the Refuge shops (4). Moderate smoke
  was observed there.

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Summary
Smoke observations were taken at 0920 LST 24
January 2004. These observations correspond
better with the model simulated smoke
distribution at 0800 but not at 0900 when surface
heating during the morning aided in the mix-out
of smoke and establishment of strong southwest
winds in the drainage layer. Model results for
0800 are compared with the observations.

• PB-Piedmont placed some smoke at the Falling
  Creek Bridge (1). Moderate smoke was observed
  there.
• PB-Piedmont placed dense smoke at the
  intersection of Juliette Rd and the Wildlife Dr
  entrance (2). Moderate smoke was observed there.
• PB-Piedmont placed no smoke at the intersection
  of Juliette Rd and the Wildlife Dr exit (3) but
  did place smoke just to the west of the
  intersection. Moderate smoke was observed at the
  intersection.
• PB-Piedmont placed no smoke at the Refuge shops.
  No smoke was observed there.

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Smoke Matrix
Smoke Prediction
Yes No
0
4
No Yes
Smoke Observation
0
0