Landsat 8. Snabba leveranser av bilder till användarna. Lars-Åke Edgardh. tisdag 9 april 13

Transcription

1 Landsat 8 Snabba leveranser av bilder till användarna Lars-Åke Edgardh

2 Keystone A single system for: Many sensors Many types of clients Hides the complexity of sensors. Specialised on: Services High volume productin tin

3 Keystone = Near Real Time (minutes) Acquisition planning Acquisition T0 Downlink Services and Products User T1 T1+ minutes T1+ minutes

4 LDCM + Keystone = ESA Near Real Time (3 hrs) Acquisition Products User Acquisition planning Downlink T1 T1+ T0 3 hrs T1+ 3 hrs + download

5 LDCM + Keystone = Near Real Time Spacecraft GNE Mission data Ingest L0Ra DPAS Subsetter L0Rp LPGS L1T/L1G Keystone Server Portal Worldwind client WMS Keystone Workflow FTP NRT < 3 hrs

6 Landsat 7 Launched April 1999 Landsat Enhanced Thematic Mapper Plus (ETM+) Eight spectral bands Bands 1-7 has a resolution of 30m Band 8 has 15m resolution Scen size 170km x 183km Landsat 7 Wavelength (micrometers) Resolution (meters) Band 1 - Visible band 2 - Visible band 3 - Visible band 4 - Near-Infrared band 5 Near-Infrared band 6 - Thermal band 7 - Mid-Infrared (30) band 8 -Panchromatic (Band 6 is acquired at 60m and processed to 30 m)

7 Landsat 8 Launched February 2013 Also called Landsat Data Continuity Mission (LDCM) Two sensors: Operational Land Imager OLI (band 1-9) Thermal Infrared Sensor TIRS (band 10-11) Landsat 8 OLI has added "ultra-blue" band 1 (coastal and aerosol studies) and 9 (cirrus cloud detection) Wavelength (micrometers) Resolution (meters) Band 1 - Visible (Coastal aerosol) band 2 - Visible band 3 - Visible band 4 - Near-Infrared band 5 - Near-Infrared band 6 - SWIR band 7 - SWIR band 8 - Panchromatic band 9 - Cirrus band 10 - Thermal Infrared (TIRS) Band 11 - Thermal Infrared (TIRS)

8 Landsat 7 vs Landsat 8

9 Processing details of LDCM Level 1 Products Processing: Level 1 T (Terrain corrected) Pixel Size: OLI multispectral bands: 30-meters OLI panchromatic band: 15-meters TIRS bands: resampled to 30 meters to match OLI multispectral bands Also an additional data quality band indicating clouds, snow etc Three decades of changes in the Birdsfoot delta of Mississippi River, USGS

10 Standard Terrain Correction - Level 1T Geometric and radiometric accuracy by applying ground control points (GCP s) and digital elevation models (DTM s) Aral sea 1973 and 2009 GCP s from GLS2000 dataset DEM include SRTM, NED, CDED, DTED, GTOPO30

11 Systematic Correction - Level 1TQ Systematic geometric and radiometric accuracy by applying data from the sensor and spacecraft Geometric accuracy within 250m Only used when GCP s not available Chernobyl 1975, 1986 (accident), 2011

12 Data characteristics GeoTIFF data format Cubic Convolution (CC) resampling North Up (MAP) orientation Universal Transverse Mercator (UTM) map projection World Geodetic System (WGS) 84 datum 12 bit dynamic range delivered in 16-bit pixel values (Landsat 7 used 8 bit) 12 meter circular error, 90% confidence global accuracy for OLI 41 meter circular error, 90% confidence global accuracy for TIRS

13 Data delivery All files will be delivered in a tar.gz compressed file Compressed Uncompressed Landsat 8 1 GB 2 GB Landsat MB 450 MB

14 USGS Landsat 8 archives Available from May Each day 400 scenes from the OLI and TIRS will be acquired Archived at the USGS EROS data center Processing to be consistent with existing Landsat archive Data ready for public download within 24 hrs

15 ESA Landsat 8 archives Available from May Each day 120 scenes from the OLI and TIRS will be received Archived at the ESA Landsat archive Processing to be consistent with existing Landsat archive Data ready for public download within 3 hrs

16 Free and open access Access to L1 products is free and open for all GMES and not GMES users registered using the standard EOPI registration. Free and open: The ESA catalogue consultation is open in the sense that it is not necessary to be a registered user to perform it. To access the data, users need to be registered and identified, providing their access credential, by ESA systems. In this context open means that the users have no restriction on the catalogue consultation and, after being identified by the system, on the Landsat-8 product that they can access. The access to the data is not subject to a fee, therefore is free.

17 Registration URL: earth.esa.int Step 1 Step 2

18 First image March 18, 2013 Rocky Mountains in Wyoming and Colorado Two images: First image is shown in natural color, created using data from OLI spectral bands 2 (blue), 3 (green), and 4 (red) Second image was created using data from OLI bands 3 (green), 5 (near infrared), and 7

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