# Presentation: 597197

## Drew Pilant, Ph.D.
Timothy Lewis, Ph.D., John Iiames, Mark Murphy (US EPA)
 Jayantha Ediriwickrema, Ph.D. (Computer Sciences Corporation)

MODIS Vegetation Workshop II, Missoula MT
   August 16, 2004

- Timothy Lewis, Ph.D., John Iiames, Mark Murphy (US EPA)
-  Jayantha Ediriwickrema, Ph.D. (Computer Sciences Corporation)
- MODIS Vegetation Workshop II, Missoula MT
-    August 16, 2004

***EPA MODIS LAI Evaluation Activities in the Albemarle-Pamlico Basin, NC/VA***

## Outline

- EPA LAI project at a glance
- Applications of MODIS LAI at EPA
- Describe field studies
- Results and observations
- Data sets for archiving

## LAI Project at a Glance

## Potential Applications of MODIS LAI (MOD15A2) at US EPA 

- Biogenic emissions models (BEIS2)
- Air quality models (CMAQ)
- Atmospheric deposition models
- Landscape characterization and monitoring
- Vegetation phenology in land cover mapping and change detection

**Notes:**
Biogenic emissions models
Air quality models
Atmospheric deposition models
Landscape characterization and monitoring
Vegetation phenology in land cover mapping and change detection

## LAI Field Studies

- Iiames, J.S., A.N. Pilant, T.E. Lewis**.** 2004. In-situ estimates of forest LAI for MODIS data validation.* in*: Lunetta, R. and J. Lyon (eds.), *Remote Sensing and GIS Accuracy Assessment*, CRC Press, Boca Raton, FL.

## Study Area: Albemarle-Pamlico Basin, NC/VA

**EPA Research Lab**
**At Research Triangle Park, NC**

***Study Area: Albemarle-Pamlico Basin, NC/VA***

## Hemiphoto: Optical Measurements of In Situ LAI

**Hemispherical photography**
- Upward looking
- Dawn/dusk/overcast days

**Notes:**
Add: 
Comments on general techniques for LAI measurement
Hemi photo
Trac profile

## TRAC: Optical Measurements of In Situ LAI

**Sunfleck profiling**: TRAC
- (Tracing Radiation and Architecture of Canopies)
- Full sun/mid-day

**Notes:**
Add: 
Comments on general techniques for LAI measurement
Hemi photo
Trac profile

## Real time differential GPS geolocation for grids/transects

## Baseline Forest Biometrics

- Tube densiometer

- Species distributions

- Grid stake

- Photo time series
- 0o 		45o

## Field LAI Sampling Grids and Transects

- 100 m

- 100 m

**Notes:**
Note: flexibility in assessing intra- and inter- stand LAI trends

## Scaling: Field Transects to Landsat ETM+

- Landsat ETM+ image
- 30 m pixels

- Quadrants and subplots inside hypothetical
- 1 km MODIS LAI pixel

## LAI Scaling: Field to MODIS

## Results and Observations

- LAI phenology shows green-up
- Understory removal effects on NDVI
- MODIS NDVI in LAI backup algorithm
- Field data: MODIS LAI direct comparison

## MODIS LAI Time Series in Albemarle-Pamlico Basin

## Before understory cut

**Before** understory cut

**After** understory cut

- Iiames, J. S., Pilant A.N. , Lewis T. Congalton R. Leaf Area Index (LAI) change detection on loblolly pine forest stands with complete understory removal,   Proc. ASPRS 2004 Annual Conference, 05/23/04, Denver, CO.

***Understory Removal in 100x100 m plot: Effect on IKONOS NDVI***

## Understory Removal in 100x100 m plot: Effect on IKONOS NDVI

- Understory removal: 3% NDVI reduction (p<0.05)

- IKONOS NDVI image

**After** understory cut

**Before** understory cut

- Iiames, J. S., Pilant A.N. , Lewis T. Congalton R. Leaf Area Index (LAI) change detection on loblolly pine forest stands with complete understory removal,   Proc. ASPRS 2004 Annual Conference, 05/23/04, Denver, CO.

## Begin your presentation here

***MOD15A2: Radiative Transfer vs NDVI Algorithm******5x5 km (25 pixels) sample***

**Notes:**
1 year, 5x5 km at Appomattox site

## MODIS NDVI: Data Challenges

## MODIS and  Hemiphoto LAI Time Series at Fairystone Site (deciduous)

***MODIS and ***** *****Hemiphoto LAI Time Series at Fairystone Site (deciduous)***

**Notes:**
Temporal spectrum

## MODIS and TRAC LAI Time Series at Appomattox Site (pine)

-  Jan Feb Mar Apr May Jun Jul Aug Sep

**+**

**+**

**+**

**+**

**+**

- LAI * 10

- MODIS LAI spectral profiles from 5 adjacent pixels

**= *****in situ***** ****TRAC** **LAI**

***MODIS and TRAC LAI Time Series at Appomattox Site (pine)***

## LAI Field Data Sets for Archiving

***LAI Field Data Sets for Archiving***

|  DATA SET | DESCRIPTION | COMMENTS |
| --- | --- | --- |
| HEMI photos | Digital hemispherical photographs from survey grids |  |
| TRAC sunfleck profiles | TRAC profiles from survey transects |  |
| Digital ground/canopy photos  | Digital photos at 0, 45, 90o |  |
| Baseline forest biometrics | Crown closure, stems/ha, diameter at breast height (DBH), diameter: height, canopy analysis, species distribution |  |
| Meteorological data | NWS, State and cooperative weather observations |  |

## LAI Image Data Sets for Archiving

|  DATA SET | DESCRIPTION | COMMENTS |
| --- | --- | --- |
| MODIS LAI Time series | Georeferenced; period 2000-2005 |  |
| MODIS NDVI time series | Georeferenced; period 2000-2005 |  |
| Landsat ETM+ images | Intermittent 1999-2004
Precision georeferenced |  |
| Air photos | circa 1990-2002 | As apropos |
| IKONOS data | Derived NDVI images | As apropos |
| Digital elevation data 
 | 30 m Shuttle Radar Topography Mission;
Possibly LIDAR for NC |  |

## Ongoing work

- Validation of TRAC and Hemiphoto methods
- Comparison with destructive harvest at NCSU sites
- TRAC/Hemiphoto repeatability measurements
- Develop 500-1000 m TRAC transect method
- Methods for scaling
- Field: Landsat ETM:MODIS
- Organize / QA Data Archiving

**Notes:**
Iiames, J.S., A.N. Pilant, T.E. Lewis. 2004. In-situ estimates of forest LAI for MODIS data validation. IN: Lunetta, R. and J. Lyons (eds.), Remote Sensing and GIS Accuracy Assessment, CRC Press, Boca Raton, FL.

Iiames, J. S., Pilant A.N. , Lewis T. Congalton R. Leaf Area Index (LAI) change detection on loblolly pine forest stands with complete understory removal,  (TIP # 04-045, Symposium Paper.) ASPRS 2004 Annual Conference, 05/23/04, in Denver, CO. 

Iiames, J. Pilant A.N. Lewis T. Accounting for error propagation in the development of a Leaf Area Index (LAI) reference map to assess the MODIS MOD15A LAI product, (TIP # 04-066, Symposium Paper.) 2004 Accuracy Conference, 06/28/04, in Portland, Maine.

- Begin your presentation here

*Thank you!*

- pilant.drew@epa.gov

*Acknowledgments*:
- NASA
- State of VA
- State of NC
- NCSU
- Duke University
- Westvaco
- International Paper