Presentation on theme: "USGS/EDC Archive Preservation Status An Update Stuart Doescher, USGS (Cheryl Greenhagen) WGISS-19 March 2005 Cordoba, Argentina."— Presentation transcript:
USGS/EDC Archive Preservation Status An Update Stuart Doescher, USGS (Cheryl Greenhagen) WGISS-19 March 2005 Cordoba, Argentina
TM and MSS Archive Conversion System (TMACS) Operations: 1992 to 2002. Number of High Density Tapes (HDT) transcribed: 32,300 –Landsat MSS, TM Number of DCRSi Cassette Tapes (DCT)s output: 3,200 Mostly in Telemetry stream format (Frame sync required to read)
WBVT summary Operated: April 1999 - May 2002 Number of HDTs converted: 21,300 Number of Digital Linear Tape (DLT 7000) generated: 143 and an additional 143 as backup Format: BSQ ( MSS-X) "orphan" data (no DIAT / SLAT) save on 172 DLTs Bad input tapes: 476 (even with cleaning & baking).
SPOT summary Operated: late April 2000 - February 2002 Number of HDTs converted: 6,100 Number of DLT 7000 tapes generated: 901 Format: MDA's FRED
Landsat Archive Conversion System (LACS) Planned Operations: June 2004 – June 2006 Input: About 6000 HDTs, 4000 DCTs, plus current Landsat 5 data Output: ~ 1000 tapes of "formatted" data and ~ 1100 tapes of "raw" data on 9940B. (200G/tape) Format: BSQ
LACS Description Ingest current Landsat 5 data from disk files Ingest data from DCRSi Cassette Tapes (DCTs) –Multispectral Scanner Archive format (MSS-A) data –Multispectral Scanner Product format (MSS-P) data –Thematic Mapper Archive format (TM-A) data –Thematic Mapper raw (TM-R) data Ingest TM-R data from High Density Tapes (HDTs) Archive the data to a high-density computer-compatible digital tape: 9940B Generate and archive browse imagery Generate inventory information for the new archive.
Data to be converted by LACS Data Set Number of Scenes Number of TapesData Volume MSS-P65,128 118 DCTs 3.2 terabytes MSS-A262,088 277 DCTs 9.5 terabytes TM-A13,733 108 DCTs 3.6 terabytes TM-R (1982 – 1994)593,563 3,431 DCTs 147.4 terabytes TM-R (1995 +)106,300 6,000 HDTs 30.0 terabytes TM-R (new)~ 8 terabytes 1,040,812 Total201.7 terabytes
LACS Status Started Operations: June 2004 Progress to Date: (January 2005) –Current Landsat 5 Data: 949 Intervals (22,061 scenes) –DCTs: 318 Tapes (2,809 Intervals, 53,697 scenes) –HDTs: 2624 Tapes (2,846 Intervals, 52,203 scenes) This is 105,900 of 1,040,812 scenes in 6 ½ months (Implies total time greater than 5 years with 4.5 years remaining - that would imply a July 2009 completion)
LACS Status LTS (LACS Transcription Subsystem) 3 Strings: –LTS1: Current Landsat 5 data only (acquired at EDC, or received on DLT from Australia.) –LTS2: DCT Input ( 2 to 3 shifts per day) –LTS3: HDT Input. (1 to 2 shifts per day) Tapes (HDTs) & tape drives (HDTRs) are cleaned before use Many of the HDTs are baked Some HDTs are tried many times before success HDTRs may require adjustment for specific sets of tapes
LACS Status LIS (LACS Integration Subsystem) 1 String: –Performs Automated Cloud Cover Assessment, Browse Generation, Quality Assignment –Provides Interactive Assessment Capability –Gives priority to current Landsat 5 data –This system is currently the bottleneck
LACS Status Issues / Problems: –Some tapes in very poor condition –LIS performance needs improvement Plans: –Continue to improve handling of poor-quality data –Performance Improvements: Run LIS on 3 Linux systems Run DCT Ingest on 2 LTS systems Run DCT Ingest on 3 LTS systems when HDTs done –Anticipate 3 time improvement (1.5 years remaining that would imply a July 2006 completion)