A global climate/interdisciplinary long-term data set

1
A global climate/interdisciplinary long-term data
set from AVHRR, MODIS and VIIRS
Ed Masuoka, Dr. Compton Tucker, Dr. Jorge Pinzon
and Dr.Sadashiva Devadiga, Hydrospheric and
Biospheric Sciences Laboratory NASA GSFC Dr.
Eric Vermote, Dr. Steve Prince and Dr. Chris
Justice, Department of Geography University of
Maryland College Park Dr. Nazmi Saleous,
Department of Geography United Arab Emirates
University and Dr. Jeff Privette, NOAA Dr. David
Roy, Geographic Information Science Center of
Excellence, South Dakota State University Dr.
Diane Wickland, Study Manager NASA Headquarters
http//ltdr.nascom.nasa.gov/ltdr/ltdr.html
Introduction
Properties of the Beta data set

• Absolute calibration coefficients derived for
  NOAA 16 bands 1 and 2 using Terra MODIS as a
  reference were compared with vicarious
  calibration coefficients derived using the ocean
  and clouds. The coefficients agreed to within
  1. Black line desert trends. Blue is B1 trends
  using Ocean and Clouds method. Red is B2

• The goal of our project is to produce a global
  Land Long Term Data Record (LTDR) from AVHRR,
  MODIS and VIIRS products for use in global change
  and climate studies. The production, quality
  assurance and distribution of the LTDR leverages
  our experience and infrastructure developed for
  MODIS.
• This moderate resolution data record will stretch
  from 1981 to 2015
• The following products will be produced for the
  LTDR for AVHRR and MODIS over the course of the
  project.
• VIS/NIR Mid-IR Surface Reflectance , Vegetation
  Indices
• BRDF/Albedo, Aerosols, Snow, LAI/FPAR, Burned
  Area
• Surface Temperature and Emissivity

• Algorithms
• Vicarious Calibration - Vermote/Kaufman
• Cloud screening - CLARVR
• Partial Atmospheric Correction
• Rayleigh (NCEP)
• Ozone (TOMS)
• Water Vapor (NCEP)
• Aerosol Retrieval over dark targets
• Products
• Daily NDVI
• Daily Surface Reflectance
• 16-Day Composited NDVI
• Monthly NDVI
• Format
• Linear Latitude/Longitude Projection

• Planned activities over next 12 months
• Complete evaluation of Beta data set
• Outreach
• Special session at Fall AGU on Land Long Term
  Data Record
• MODIS Land Collection 5 workshop January 2007
• Implement BRDF correction of AVHRR data to
  remove biases
• introduced by the orbital drift and changes
  in the solar and
• viewing geometries throughout the record
• Complete implementation of LAI/FPAR and albedo
  algorithms
• Further comparisons of AVHRR and MODIS data sets
  to quantify
• differences and address continuity issues in
  higher order products
• Put improved data set online for community
  evaluation
• Implement Burned Area algorithm

Approach
NOAA-11 - 1992193 (7/11/1992) Ch1,Ch2 and NDVI

• Apply Pathfinder 2 algorithms for processing
  AVHRR 1981-2000
• Create products from AVHRR and MODIS products
  at same spatial resolution
• and from 2000 to present use MODIS to
  improve AVHRR products

Evaluating quality of the data set

• Quality assessment using MODIS approach
  (Devadiga/Roy)
• Inspection of global browse images
• Time series analysis
• Known Issues with products posted on Q/A website
• Statistical analysis using non-linear tools
  (Pinzon/Tucker)
• Verify stability of calibration
• Comparison to GIMMS and Pathfinder
• Verify theoretical errors using Aeronet data and
• develop product uncertainty estimates
  (Vermote/Nagol)

Abnormally higher values in NOAA-11 over deserts
were tracked to the use of incorrect calibration
coefficients in production. This problem was also
detected by the operational Q/A team see (time
series) above and is being corrected.

• Coincident MODIS/AVHRR data were used to
  develop an approach for water vapor retrieval
• from AVHRR.

50x50km AVHRR data cuts centered on Aeronet sites
Surface reflectance NDVI time series plots on Q/A
web page
Use Aeronet AOT and Water Vapor to assess errors
arising from limited atmospheric correction

• Receive feedback users of the Beta dataset
• Heidinger/Kogan (NOAA), King (CSIRO) and Leroy
  (CESBIO) Calibration
• Myneni (BU) LAI, Brown (GSFC) NDVI, Pinheiro
  (GSFC) and Jin (UMD) Brightness/Surface
  Temperature
• Post known problems with the LTDR at Quality
  Assurance web page

Joint Biodiversity, Terrestrial Ecology, and
Applied Sciences Workshop