# Presentation: 247489

## Piedmont National Wildlife Refuge

- 15 February 2006
- Smoke Simulation Analysis
- Gary L. Achtemeier
- USDA Forest Service
- Athens, GA

## Task Description

- The following set of slides summarize a PB-Piedmont post-burn analysis of smoke movement in the aftermath of two (426 and 643 acre) prescribed burns conducted by the Piedmont National Wildlife Refuge. These burns were conducted on 15 February 2006. The model simulations run from 1600 EST 15 February through 0800 EST 16 February. Model smoke locations are compared with field observations collected by personnel from the Piedmont National Wildlife Refuge.

## Weather

- Weather during the burn and the post-burn smoke movement period was variably cloudy with a stretch of clear skies during the middle of the night. A high pressure center moved from southern Georgia to South Carolina by the end of the simulation period. Winds gradually shifted from the southwest to the southeast. The below figure gives a measure of the strength of the large scale forcing during the analysis period. Forcing of 7.6 – 12.2 m/sec was sufficient to overcome drainage flow formation in northwest-southeast oriented valleys but to strengthen flows in east-west oriented valleys.

## Modeling Information

- PB-Piedmont Version 5.0-2006
- Grid spacing = 60m
- Domain size = 320x374 -> 19.2x22.4 km
- Visual domain = 10.0x8.8 km
- Weather data: Hourly METAR
- Elevation data: USGS 30 m DEM
- Elevation contour interval = 10 meters
- Elevation range is 88 – 208 meters

## The PB-Piedmont domain, roads, observation points for 15 February 2006. The yellow polygons enclose the burn sites. 

- The PB-Piedmont domain, roads, observation points for 15 February 2006. The yellow polygons enclose the burn sites.

## The modeled location of smoke on the ground assumes smoldering is coming from random locations within the model burn areas. Initial winds are from the south at 5 m/sec beginning at 1630 EST. Note that this image is just the viewing domain. The time is 1800 EST, 13 minutes before sunset.

## The smoke plume at 2000 15 February 2006. The plumes have broken into patches of smoke that are concentrated in the valleys located downwind from the burn sites. Note that drainage flows are transporting smoke downstream through two NE-SW oriented valleys from the southernmost burn site.

## The PB-Piedmont smoke plume at 0000 EST 16 February 2006. Smoke from the southern burn site has drained into and turned northwestward in the Okmulgee River valley (dark green strip oriented NW-SE). Smoke from the southern burn site has also been carried northwest to merge with smoke from the northern burn site. Smoke has left the area around Points 6-8 along the NE edge of the southern burn site.

## The PB-Piedmont smoke plume at 0600 LST 16 February 2006. Plumes from both burns have turned to blow more toward the west leaving a scattering of particles over large areas between the burn sites. The red dots identify where smoke and fog might coexist.

## Smoke Location Evaluation:Interpreting the Observations Shown in the Next Slide

- Red symbol means smoke observed
- Green symbol means smoke not observed
- Circle means model matched observation
- Triangle means model unsuccessful

## PB-Piedmont analysis & observations 0700 EST

- 6: No smoke (0612)

- 7: No smoke (0618)

- 8: No smoke (0622)

- 9: Smoke on unit (0624)

- 5: No smoke (0607)

- 10: Slight smoke (0628)

- 11: Slight smoke (0630)

- Click left mouse button to view observation points.

- 12: Slight smoke (0635)

- 13: No smoke (0639)

- 14: Slight smoke (0648)

- 15: Smoke (0651)

- 17: Slight smoke (0700)

- 18: No smoke (0702)

- 16: Slight smoke (0656)

- 19: No smoke (0705)

- 20: Slight smoke (0708)

- 21: Slight smoke (0712)

- 22: Slight smoke (0717)

## PB-Piedmont analysis & observations 0700 EST

- 24: No smoke (0620)

- 25: Thick smoke (0623)

- 26: Slight smoke (0625)

- 27: Thick smoke (0629)

- 23: No smoke (0722)

- 28: Thick smoke (0632)

- 29: Smoke (0636)

- Click left mouse button to view observation points.

- 30: Smoke (0638)

- 31: Slight smoke (0646)

- 32: Smoke (0651)

- 33: Smoke (0655)

- 35: Light smoke (0700)

- 36: Slight smoke (0704)

- 34: Slight smoke (0658)

- 37: Light smoke (0708)

- 38: No smoke (0713)

- 39: No smoke (0720)

## Summary:

- PB-Piedmont was correct at 24 of the 35 smoke/no-smoke observation points.
- Most of the 11 failures occurred near smoke plume boundaries or where very little or slight smoke was observed.

## Smoke Matrix

- Smoke Prediction

- Yes                 No

- Smoke Observation

-   No                Yes

- 20

- 4

- 6

- 5