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 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 Remotely Sensed Data: MODIS LAI (MOD15A2) 8 day time series MODIS NDVI (MOD13Q1) 16 day time series Landsat ETM+ time series (2-8 images/site) 4 IKONOS XS scenes Digital Elevation Model Field Measurements at Multiyear Study Sites, : TRAC sunfleck profiling Hemispherical photography Baseline forest biometrics Ground and canopy photos for each site visited

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

LAI Field Studies Iiames, J.S., A.N. Pilant, T.E. Lewis 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.

Long term field sites: EPA Research Lab At Research Triangle Park, NC Study Area: Albemarle-Pamlico Basin, NC/VA EPA RTP

Hemiphoto: Optical Measurements of In Situ LAI Hemispherical photography Upward looking Dawn/dusk/overcast days

TRAC: Optical Measurements of In Situ LAI Sunfleck profiling: TRAC (Tracing Radiation and Architecture of Canopies) Full sun/mid-day

Real time differential GPS geolocation for grids/transects

Baseline Forest Biometrics Tube densiometer Species distributions Grid stake 8/6/2002 7/29/2002 Photo time series 0 o 45 o

Field LAI Sampling Grids and Transects 100 m 50 m PPFD (light intensity) Canopy gap

Scaling: Field Transects to Landsat ETM+ Landsat ETM+ image 30 m pixels Quadrants and subplots inside hypothetical 1 km MODIS LAI pixel Subplots Two 50 m lines Quadrants 100x100 m Fairystone, VA site: montane province

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 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: 3% NDVI reduction (p<0.05) IKONOS NDVI image After understory cutBefore understory cut 0523_ _2002 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 Failure RT Algorithm (Backup) Success RT Algorithm MOD15A2: Radiative Transfer vs NDVI Algorithm 5x5 km (25 pixels) sample

MODIS NDVI: Data Challenges Version 3 Version 4

+ + Jan Feb Mar Apr May Jun Jul Aug Sep LAI * 10 MODIS LAI spectral profiles from 5 adjacent pixels = in situ hemispherical photo LAI + + MODIS and Hemiphoto LAI Time Series at Fairystone Site (deciduous)

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

LAI Image Data Sets for Archiving DATA SETDESCRIPTIONCOMMENTS MODIS LAI Time seriesGeoreferenced; period MODIS NDVI time seriesGeoreferenced; period Landsat ETM+ imagesIntermittent Precision georeferenced Air photoscirca As apropos IKONOS dataDerived NDVI imagesAs apropos Digital elevation data30 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 m TRAC transect method Methods for scaling  Field: Landsat ETM:MODIS Organize / QA Data Archiving

Begin your presentation here Thank you! Acknowledgments: NASA State of VA State of NC NCSU Duke University Westvaco International Paper