Temporary Availability of Continental Composites

In the process of producing a global composite, the world is divided into the twelve regions as defined by the interrupted Goode's homolosine projection (see Steinwand 1994 ). This allows for more efficient use of computer resources and data management throughout the development of a global composite. In practice, the regions generally correspond to continents, for example the two regions that comprise North America.

As a result, it is possible to provide the intermediate continental composites for specific time periods in advance of a complete global composite of the same time period. The availability of the continental data will vary in time and geogeoraphic location. It is anticipated that as a global composite is produced, the complimentary continental composites will only be available as subsets of the global data sets and retrievable through the global composite interface.

The continental composites are in the interrupted Goode's Homolosine projection. For specific information, please refer to the map projection documentation.

Questions? Please be sure to check the detailed information available from the Global Land 1-KM AVHRR Project web site by clicking here .

Notice to Global 1-km AVHRR Data Users

Over the past few months we have provided data via this interface to test and evaluate the data compression, geographic and resolution subsetting, and network performance for data distribution. The data provided did not completely conform to IGBP processing standards in all cases.

However, all the data now available through this improved interface does comply with the IGBP standards. The primary difference is in the scaling of the data values for both byte and integer data. We recommend that any data acquired via this interface prior to APRIL 15, 1995 not be used in any comparative analysis with the data now being provided. The different scaling methods will likely produce erroneous results.

Notice

The May 11-20 and May 21-31, 1992 global and North America continent 10-day composite data have been modified (as of October 2) to correct a problem in North America. We recommend discarding the old versions and acquiring the revised data. If you have any questions, please contact DAAC User Services.

FTP access to North America AVHRR 10-day composite data

	For additional dates for North America, please extract North America from theGlobal AVHRR 10-day composite data.	Period April 1-10, 1992 April 11-20, 1992 April 21-30, 1992 May 1-10, 1992 May 11-20, 1992 May 21-30, 1992 June 1-10, 1992 June 11-20, 1992 June 21-30, 1992 July 1-10, 1992 July 11-20, 1992 July 21-30, 1992 August 1-10, 1992 August 11-20, 1992 August 21-30, 1992 September 1-10, 1992 September 11-20, 1992 September 21-30, 1992 October 1-10, 1992 October 11-20, 1992 October 21-30, 1992 November 1-10, 1992 November 11-20, 1992 November 21-30, 1992 December 1-10, 1992 December 11-20, 1992 December 21-30, 1992 January 1-10, 1993 January 11-20, 1993 January 21-30, 1993 February 1-10, 1993 February 11-20, 1993 February 21-30, 1993 March 1-10, 1993 March 11-20, 1993 March 21-30, 1993
Select the North American 10 day period to download:

Each band must be retrieved separately. Select the desired band.
Band: 1...AVHRR channel 1 2...AVHRR channel 2 3...AVHRR channel 3 4...AVHRR channel 4 5...AVHRR channel 5 6...NDVI 7...Satellite zenith 8...Solar zenith 9...Relative azimuth 10...Date index

The data can be compressed with the GNU gzip compression software program before it is delivered. Compression: gzip unix none

The data is stored as a raw image file 15568 pixels wide by 8674 lines. The data files are stored on a robotic mass-storage device so there may be a delay of up to 4 minutes while the media is retrieved.