# Presentation: 335029

## Piedmont National Wildlife Refuge

- 09 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 (996 and 572 acre) prescribed burns conducted by the Piedmont National Wildlife Refuge. These burns were conducted on 09 February 2006. The model simulations run from 1600 EST 09 February through 0800 EST 10 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 clear. A high pressure center moved from northern Alabama to southeast Georgia by the end of the simulation period. Winds gradually shifted from the northwest to the south. The below figure gives a measure of the strength of the large scale forcing as the high pressure center moved through. Moderate forcing of 7 m/sec gave way to weak forcing of less than 4 m/sec during most of the night. This favored strong drainage flow formation. However, from midnight on, PB-Piedmont simulated fog in the basins. This weakened drainage flows allowing for the transport of smoke from valleys to higher ground.

## Modeling Information

- PB-Piedmont Version 5.0-2006
- Grid spacing = 60m
- Domain size = 338x473 -> 20.2x28.4 km
- Visual domain = 18.8x20.4 km
- Weather data: Hourly METAR
- Elevation data: USGS 30 m DEM
- Elevation contour interval = 12 meters
- Elevation range is 85 – 225 meters

## The PB-Piedmont domain, roads, observation points for 09 February 2006. The yellow polygons enclose the burn sites. 

- The PB-Piedmont domain, roads, observation points for 09 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 northwest at 5 m/sec beginning at 1630 EST. Note that this image is just the viewing domain. The time is 1800 EST, 8 minutes before sunset.

## The smoke plume at 2000 09 February 2006. The plumes have broken into patches of smoke that are concentrated in the valleys located downwind from the burn sites.

## The PB-Piedmont smoke plume at 0000 10 February 2006. Red dots locate where smoke and fog might coexist. A drainage flow carries smoke from the northern burn site to cross a road midway between Points 26 & 27. Smoke from the southern burn site has drained into and turned northwestward in the Okmulgee River valley northwest of Point 45.

## The PB-Piedmont smoke plume at 0600 LST 10 February 2006. PB-Piedmont simulates widespread smoke and fog. Drainage flows have connected smoke between the two burn sites. Synoptic forcing has blown smoke northwestward from the northern burn site and has pushed smoke up the full length of the Oakmulgee River valley shown in the figure. 

- The PB-Piedmont smoke plume at 0600 LST 10 February 2006. PB-Piedmont simulates widespread smoke and fog. Drainage flows have connected smoke between the two burn sites. Synoptic forcing has blown smoke northwestward from the northern burn site and has pushed smoke up the full length of the Oakmulgee River valley shown in the figure.

## 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: Slight smoke (0633)

- 7: Slight smoke (0636)

- 8: Slight smoke (0639)

- 9: Light smoke (0641)

- 5: Slight smoke (0627)

- 10: Smoke (0643)

- 11: Smoke (0645)

- Click left mouse button to view observation points.

- 12: Dense smoke (0647)

- 13: Dense smoke (0650)

- 14: Light smoke (0652)

- 15: Smoke (0655)

- 17: Dense smoke (0700)

- 18: Dense smoke (0702)

- 16: Dense smoke (0658)

- 19: Light smoke (0705)

## PB-Piedmont analysis & observations 0700 EST

- 21: Smoke (0710)

- 22: Light smoke (0714)

- 23: Smoke (0716)

- 24: Slight smoke (0724)

- 20: Light smoke (0707)

- 25: Smoke (0726)

- 26: Light smoke (0728)

- Click left mouse button to view observation points.

- 27: Smoke (0732)

- 28: Smoke (0734)

- 29: Light smoke (0736)

- 30: No smoke (0606)

- 32: No smoke (0615)

- 33: Slight smoke (0618)

- 31: No smoke (0610)

- 34: Slight smoke (0622)

## PB-Piedmont analysis & observations 0700 EST

- 36: Light smoke (0626)

- 37: No smoke (0632)

- 38: Smoke (0635)

- 39: Thick smoke (0639)

- 35: Slight smoke (0624)

- 40: Thick smoke (0642)

- 41: Thick smoke (0717)

- Click left mouse button to view observation points.

- 42: Thick smoke (0719)

- 43: Smoke/haze (0722)

- 44: Smoke/haze (0724)

- 45: Smoke/haze (0726)

- 47: No smoke (0739)

- 46: Smoke/haze (0735)

## Summary:

- PB-Piedmont was correct at 32 of the 42 smoke/no-smoke observation points.
- 3 of the 10 failures occurred at the southern edge of the northern burn site. PB-Piedmont blew smoke north. The model does not include land use data. Thus it shows a tendency to under-forecast smoke at ridgeline burn perimeters along roads surrounded by forest.
- 2 of the 10 failures were located near smoke but not close enough to justify a correct prediction.

## Smoke Matrix

- Smoke Prediction

- Yes                 No

- Smoke Observation

-   No                Yes

- 27

- 5

- 0

- 10