ACRES MODIS Data from TERRA and ACQUA satellite

Note: This metadata describes the dataset in accordance with the ANZLIC (Australia New Zealand Land Information Council) Core Metadata Guidelines Version 2.

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Dataset citation

ANZLIC unique identifier: ANZCW0703005429

Title: ACRES MODIS Data from TERRA and ACQUA satellite

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Custodian

Custodian: Geoscience Australia

Jurisdiction: Australia

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MODIS (Moderate Resolution Imaging Spectroradiometer) is the key instrument aboard the Terra (EOS AM-1) satellite, launched on 18 December 1999. MODIS is viewing the entire Earth's surface every 1 to 2 days, acquiring data in 36 spectral bands over a 2330 km swath. A second MODIS sensor will be on board the Aqua (EOS PM-1) satellite due for launch in late 2001 or early 2002.

ANZLIC search words:

PHOTOGRAPHY AND IMAGERY Mapping
PHOTOGRAPHY AND IMAGERY Remote Sensing Mapping
PHOTOGRAPHY AND IMAGERY Satellite Mapping

Spatial domain:

locality map

Geographic extent name: AUSTRALIA EXCLUDING EXTERNAL TERRITORIES - AUS - Australia - Australia

Geographic extent polygon: 112 -9, 154 -9, 154 -44, 112 -44, 112 -9,

Note: The format for each Geographic extent name is: Name - Identifier - Category - Jurisdiction (as appropriate) See GEN Register

Geographic bounding box:: North bounding latitude: -9 °; South bounding latitude: -44 °; East bounding longitude: 154 °; West bounding longitude: 112 °

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Data currency

Beginning date: 2001-10-15

Ending date: Not Known

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Dataset status

Progress: In Progress

Maintenance and update frequency: As required

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Access

Stored data format:: DIGITAL - Sat.image Satellite imagery

Available format type:: DIGITAL - Sat.image Satellite imagery

Access constraints:

Data files may be downloaded from Geoscience Australia's website at http://www.auslig.gov.au/acres/prod_ser/modisprice.htm. The data are subject to Copyright. A licence agreement is required.

Order Product

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Data quality

Lineage:

The MODIS data set is acquired by earth orbiting remote sensing satellites. These satellites carry two types of sensor systems known as "active" and "passive". A "passive" system generally consists of an array of small sensors or detectors which record (as digital numbers) the amount of electro-magnetic radiation reflected and/or emitted from the Earth's surface. MODIS is a passive system.

The digital data acquired by the satellites are transmitted to ground stations and can be used to reconstitute an image of the Earth's surface not too dissimilar to an aerial photograph. Data are received through the ACRES antennae at the Data Acquisition Facilities at Alice Springs and Hobart enabling coverage of the Australian landmass and New Zealand. The recorded data are air-freighted and sent via a high speed communication link daily to the Data Processing Facility in Canberra where it is catalogued and archived. Data are recorded and archived by orbit, or swath, allowing parts of the swath to be extracted by its geographical coordinates. If the region of interest extends across two adjacent paths the appropriate data set from each path will need to be extracted. Because of the orbital parameters of the satellite, adjacent paths are not acquired sequentially and information from each path may differ according to the time delay between the two passes. To assist cataloguing and ordering, a path is segmented into individual scenes.

Diagrams and formulae are available to assist in relating geographical coordinates to the satellite orbit number. Each scene acquired by ACRES is sub-sampled and produced in its Digital Catalogue access to which is available through the WWW. Data are provided as digital data products which can be viewed and manipulated on a variety of software systems. However, the data transmitted to Earth from an Earth observation satellite are in a form unsuitable for use by customers so ACRES processes this raw data in varying degrees to produce products suitable for use by clients.

ACRES processes MODIS data within 24 hours of acquisition and places it on the ACRES web pages for ftp download for a limited time. Historical MODIS data may be processed from raw data after a client has placed an order for a specific product. This is due to the large quantities of data received from a satellite and the large range of product options available.

Positional accuracy:

Within 1km, after specialised processing.

Attribute accuracy:

Not Relevant

Logical Consistency:

As the data is acquired in seamless north-south swaths each swath is internally consistent. However, swaths are acquired on different dates and while swaths can be joined to cover larger areas, changes in ground conditions between acquisition dates may be apparent in the resulting mosaic.

Completeness:

A new coverage of Australia is obtained every 2 days (from 3 swaths). The exact orbits repeat themselves every 16 days.

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Contact information

Contact organisation: Geoscience Australia (GA)
Contact position: Director, Sales and Distribution, ISB
Mail address: GPO Box 378
Mail address:
Locality: Canberra
State: ACT
Country: Australia
Postcode: 2601
Telephone: +61 2 6249 9966
Facsimile: +61 2 6249 9960
Electronic mail address: sales@ga.gov.au

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Metadata information

Metadata date: 2008-09-01

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Additional metadata

Metadata reference XHTML: http://www.ga.gov.au/meta/ANZCW0703005429.html

Metadata reference XML: http://www.ga.gov.au/meta/ANZCW0703005429.xml

Size of the dataset: A full scene is (uncompressed) approximately 3.5Mb for 1km data, 21.6Mb for 500m data and 86.4Mb for 250m data.

Scale/resolution: 250, 500 and 1000 metre pixel resolution

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