EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia03/000

CRAIG SMITH

CURRENT MODIS DB PRODUCTS AND FUTURE PLANS AT ACRES,

GEOSCIENCE AUSTRALIA

Australian Government

Geoscience Australia

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

ACRES MODIS NRT Online Products

• All Terra & Aqua day & night Passes acquired• Available for 7-10 days at no charge, following User registration• Level 1b and Map oriented (Lambert Conformal Projection) products

available• Browse JPEG - Bands 1,4,3 as RGB• Metadata file - 1 for each spatial

resolution set• Map oriented products available in ENVI & ER Mapper format – allows

for improved access for non-expert users• Approximately 100 Terra Bytes per month of MODIS data being

downloaded from ACRES ftp site

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

ACRES MODIS Archive Products

• Product specifications similar to the NRT Online products• Post pass ephemeris is used in the generation of archive

products• How do we generate additional value from the MODIS

archive• The value of ACRES 26 year Landsat archive increases

every year – lessons for the MODIS archive!• Opportunity to optimise the processing of the data, and

improved information extraction, using local conditions and knowledge for improved higher level products

• Investigating the generation of higher level products, with consideration given to the institutional MODIS products available from the DAAC

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

ACRES PRODUCTS & SERVICES

• Sentinel Project – Major operational application of NRT MODIS is the mapping of thermal anomalies (Hotspots)

• Almost complete raw data archive of MODIS, TERRA & AQUA, data• MODIS complements our products and services from our archive of

Landsat MSS, TM, & ETM, ERS, RADARSAT & JERS data• Dedicated AVHRR reception facility in Alice Springs – NRT Online

products available from ACRES then archived by CSIRO• Discussions with AVHRR users about potential MODIS products• Investigating the development of a grassland curing product • Geoscience Australia is responsible the Oceania ALOS Data Node

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

• Canberra

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

MODIS Data Processing Flow at ACRES – Part I

Data acquisition at Alice and Hobart

Direct Ingest System

Raw data archive On SDLT

RT-STPS PDS

IMAPP at DAFHot Spot algorithm

Sentinel System

T0

T20

1. Tape archive at DPF2. Tape transfer to DLI

3. Tape transfer to BoM

Tweekly

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

MODIS Data Processing Flow at ACRES – Part II

Data acquisition at Alice and Hobart

Direct Ingest System

RT-STPS PDS

T0

Canberra

WAN

Online products

T2-8hr

T2hr

IMAPPSystem

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

MODIS DB R&D PROJECTS

• LOCATIONAL ACCURACY ASSESSMENT

• CLOUD COVER MASK (MOD35) ASSESSMENT

• ATMOSPHERIC AND BRDF CORRECTIONS

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

MODIS LOCATIONAL ACCURACY

• Multi-temporal sub-pixel (250 m) registration of MODIS AQUA & TERRA data are important for most applications

• The locational accuracy specifications for TERRA MODIS data are about 50 m (1 σ) at nadir

• The accuracy specifications for NRT AQUA MODIS data are larger as AQUA has no on-board GPS capability

• The major determinant of the locational accuracy of MODIS products in a NRT environment is the accuracy of the ephemeris used in product generation

• Post past ephemeris are not available at the time of NRT product generation. The locational accuracy of ACRES NRT products are approaching the theoretical limit

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

MODIS LOCATIONAL ACCURACY

• ACRES is implementing geometric quality assurance procedures for our MODIS products

• A sample of MODIS products are automatically assessed against a 2002 Landsat ETM+ mosaic of Australia, resampled to 250 metre pixel size

• An intensity based image matching technique is used to compare image chips taken from a regular grid of MODIS products with the database of Landsat image chips

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

MODIS LOCATIONAL ACCURACY

• The mean error of ACRES NRT MODIS Terra and AQUA products is 50 and 200 metres respectively with a standard deviation of 135 and 160 metres respectively

• These figures are derived from a sample of all pixels (nadir & off nadir)

• Residuals will be used to update the geocoding information provide with the ENVI & ER Mapper formatted products

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

MODIS CLOUD COVER MASK• The Cloud Cover (CC) mask algorithm (MOD35) is being

be verified for Australian conditions• The design of the algorithm is conservative • There are five groups of spectral tests. If one of the five

group tests maps a pixel as cloudy or probably cloudy then the pixel will be labelled accordingly

• Currently investigating of the source of false positives• The spectral band thresholds and ground cover types

(desert, ocean etc) are the two main variables that are used to estimate cloud cover

• Investigating issues of modifying the threshold values in the spectral tests and Olsson land classification

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

ATMOSPHERIC & BRDF CORRECTION• A research project within the Co-operative Research Centre for Spatial

Information - lead Participants are Geoscience Australia, Western Australia Dept of Land Information & Cutin University

• A major component of this project is validating, and applying dynamic corrections for atmospheric effects, water vapour MOD05, and aerosols MOD04

• Dynamic inputs being derived from MODIS data with supporting information from the Australian Bureau of Meteorology

• This work is primarily being undertaken at Dept of Land Information and Curtin University, Perth

• Dynamic inputs for both:-

• DB Version of MOD09• SMAC code ( Rahman & Dedieu )

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

MODIS

09/09/2003

01:27UTC

03:04UTC

Top-Of-Atmosphere-Reflectance Bottom-Of-Atmosphere-Reflectance

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

Taken from MOD09 ATBD Vermote and Vermeulen (1999)

Flow chart of atmospheric correction algorithm

H2O vapour is the primaryfocus of the current work

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Radiosonde Locations

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

The algorithms producea water vapour map over WA at 1km resolution.

Precipitable Water (kgm-

2 )

MODIS Terra 02:08 UTC17/12/2004

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

Validation of MODIS H2O algorithms

Sobrino et al.

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EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

Analysis of data rejected by the cloud mask

Choice of cloud mask may limit ‘good’ data by up to 25%

DLI Cloud MaskIMAPP Cloud Mask

EOS/NPP DIRECT READOUT MEETING BENEVENTO OCTOBER 2005 Geoscience Australia

Grazie

Nov 2003 Apr 2004

NDVI South East Australia