Land Archive

Last Update: November 14, 2007

Collection 4

At the present time MODAPS land forward processing is being conducted using Collection 4 codes. This will continue until the Collection 5 codes are introduced in mid-December. All land products from this processing are being and will be exported to the LP or NSIDC DAACs.

The GES DAAC stopped the production of Collection 4 L1 data products on dataday 55 (February 24, 2006). The GES DAAC will continue to distribute Collection 4 L1B, geolocation, and cloud mask for intervals earlier than dataday 55 until early-September when the distribution of all Collection 4 data products will be terminated. The distribution of L1B, geolocation, and cloud mask products after dataday 55 became the responsibility of MODAPS after February 24, 2006. The distribution of these products for all of the Collection 4 interval will become MODAPS responsibility after early-September, 2006 (Transition Issues).

MODAPS will archive Collection 4 cloud mask/profiles in LAADS. However, MODAPS will not archive either Collection 4 L1B or geolocation products in LAADS. MODAPS maintains a "rolling" data pool for Collection 4 forward processing L1B and geolocation. This data pool has a capacity of 21 datadays (compressed using hrepack) of Aqua and 21 datadays of Terra products (Data Access).

Collection 5

MODAPS will export Collection 5 land data products to the LP/NSIDC DAACs for both reprocessing and forward processing. The data products, including data volumes, archived at these locations are shown in the Land Archive Table (updated 11/14/07) (MSExcel spreadsheet).

The atmosphere Science Team has requested the inclusion of certain Collection 5 land data products in the LAADS archive. Albedo products (MCD43Ax, MCD43Bx, and MCD43C1C) will be archived. The reprocessing of Terra products started on June 30, 2006 (Collection 5 Land Reprocessing Plan).

The cloud mask and geolocation products will also be archived in LAADS and the L1B products will be archived in "rolling" data pools, with the exception of the CONUS and European regions (and later Asia) which will be permanently archived in LAADS.

As described in the Collection 5 Land Reprocessing Plan, the first stage of the reprocessing will utilize a single processing machine for the Terra-only interval. The second stage will utilize two machines for the Aqua/Terra interval. The second stage processing will therefore include two data pools. This will be transparent to users accessing the data products through LAADS.

The capacity of each data pool will be approximately 120 datadays of L1B (compressed using hrepack). This is equivalent to approximately 30 calendar days of reprocessing and forward processing production. User access to the data pool will be provided through the LAADS. Any user requests for Collection 5 data pool products older than the most recent 30 days of production should also be submitted through LAADS. This will be satisfied on a processing-on-demand basis (LAADS Capabilities).

Details of the land reprocessing plan can be found at Collection 5 Land Reprocessing Plan. Data access instructions are given under Data Access. The LAADS Web Data Availability page provides a detailed identification of the Collection 5 data products available through LAADS.