29 th Annual Louisiana RS/GIS Workshop April 23, 2013 Cajundome Convention Center Lafayette, Louisiana

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1 Landsat Data Continuity Mission 29 th Annual Louisiana RS/GIS Workshop April 23, 2013 Cajundome Convention Center Lafayette, Louisiana

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3 Landsat 5 Sets Guinness World Record For 'Longest Operating Earth Observation Satellite' Outliving its three-year design life, Landsat 5 delivered high-quality, global data of Earth's land surface for 28 years and 10 months. March 1, Landsat 5 was designed and built at the same time as Landsat 4 and carried the same two instruments: the Multispectral Scanner System (MSS) and the Thematic Mapper (TM). The Landsat Data Continuity Mission (LDCM) launched from Vandenberg Air Force Base in California at 10:02 a.m. PST on February 11, 2013.

4 Opening New Eyes LDCM is a joint mission of NASA and the Department of Interior's U.S. Geological Survey. Landsat Data Continuity Mission (LDCM) released its first images of Earth, collected at 1:40 p.m. EDT on March 18. The first image shows the meeting of the Great Plains with the Front Ranges of the Rocky Mountains in Wyoming and Colorado. Credit: USGS/NASA Earth Observatory

5 Landsat 8 Data Product By the end of May 2013, data from the Landsat 8 satellite will be available to all users. Each day, 400 scenes acquired by the Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) will be archived at the USGS EROS Center, and will be processed to be consistent with current standard Landsat data products. Data will be ready to download within 24 hours of reception.

6 Processing: Pixel Size: Processing details of LDCM Level 1 Products Level 1 T- Terrain Corrected Data Characteristics: GeoTIFF data format OLI multispectral bands: 30-meters OLI panchromatic band: 15-meters TIRS bands: resampled to 30 meters to match OLI multispectral bands Cubic Convolution (CC) resampling North Up (MAP) orientation Universal Transverse Mercator (UTM) map projection (Polar Stereographic for Antarctica) World Geodetic System (WGS) 84 datum 12 meter circular error, 90% confidence global accuracy for OLI 41 meter circular error, 90% confidence global accuracy for TIRS 16-bit pixel values Data Delivery: HTTP Download

7 Sample images of four areas important to LDCM can be found at Images of the LDCM s Underfly with Landsat 7 can be found at LDCM Documentation and Information LDCM Mission Data Data Format Control Book (Rawest form) -.pdf (1.13 MB) LDCM Level 0 Reformatted Data Format Control Book (Format prior to product generation) -.pdf (1.63 MB) LDCM Level 1 Data Format Control Book (Products) -.pdf (410 KB) LDCM CAL/VAL ALGORITHM DESCRIPTION DOCUMENT -.pdf (10.2 MB) Additional information about LDCM can be found at

8 Question: How will LDCM differ from previous Landsat satellites? Answer: The LDCM satellite will carry two push-broom instruments: the Operational Land Imager (OLI), and the Thermal Infrared Sensor (TIRS). The spectral bands of the OLI sensor, while similar to Landsat 7 s ETM+ sensor, provides enhancement from prior Landsat instruments, with the addition of two new spectral bands: a deep blue visible channel (band 1) specifically designed for water resources and coastal zone investigation, and a new infrared channel (band 9) for the detection of cirrus clouds. A new Quality Assurance band will also be included with each data product. This will provide information on the presence of features such as clouds, water, and snow. The TIRS instrument collects two spectral bands for the wavelength covered by a single band on the previous TM and ETM+ sensors. This page describes the band designations for all Landsat sensors:

9 Bandpass wavelengths for Landsat 8 OLI and TIRS sensor, compared to Landsat 7 ETM+ sensor The data quality (signal to noise ratio) and radiometric quantization (12-bits) of the OLI and TIRS will be much higher than previous Landsat instruments (8-bit for TM and ETM+), providing significant improvement in the ability to detect changes on the Earth s surface. At least 400 scenes will be collected daily placed into the USGS archive to become available for download within 24 hours after acquisition.

10 Question: What data products will be available for Landsat 8 scenes? Answer: Data products from Landsat 8 will become available approximately 100 days after launch, and will be consistent with the existing standard Level-1 (orthorectified) data products created using Landsat 1 to Landsat 7 data. The standard Level 1 data and LandsatLook (full-resolution jpg) products will be available for download at no charge from GloVis, EarthExplorer or the LandsatLook Viewer. Details about processing levels of Landsat data products can be found on

11 Question: What files will be included when I download a Landsat 8 scene? Answer: Along with similar multispectral bands used on the L7 ETM+ sensor, the addition of a new coastal/aerosol band and a new cirrus band will provide improved data products. Two thermal bands (TIRS) capture data with a minimum of 100 meter resolution, but will be registered to and delivered with the OLI data product. The file sizes will be larger than existing Landsat 7 data, due to additional bands and improved 16-bit data product.

12 All files will be delivered in a tar.gz compressed file: A new Quality Assurance (QA) band will be also included. This band will provide bit information regarding conditions that may affect the accuracy and usability of a given pixel. More information can be found at : How do I use the Landsat 8 Quality Assessment (QA) band?. Compressed Uncompressed LDCM/Landsat 8 1 GB 2 GB Landsat MB 450 MB all file sizes approximate

13 Answer: The newly added cirrus band (band 9: µm) will provide better detection of cirrus cloud contamination in each scene. Cirrus clouds will appear bright while most land surfaces will appear dark through cloud-free atmospheres containing water vapor. While this band will not be used together with other multispectral channels, it will be useful in determining cloud contamination. Question: What is the new Coastal/Aerosol band and how will it be used? Answer: The newly added coastal/aerosol band (band 1: µm) will allow the closer investigations of coastal waters, relative to MODIS and SeaWiFS sensors, as well as estimating the concentration of aerosols in the atmosphere. Question: What is the new Cirrus band and how will it be used?

14 Question: How will the 12-bit data received from Landsat 8 improve data products? Answer: Landsat 8's OLI and TIRS sensors provide improved signal-to-noise (SNR) radiometric performance quantized over a 12-bit dynamic range. This translates into 4096 potential grey levels in an image compared with only 256 grey levels in previous 8-bit instruments. Improved signal to noise performance will enable improved characterization of land cover state and condition. Products will be delivered as 16-bit images. Question: How do LDCM/Landsat 8 band combinations differ from earlier Landsat satellite data? Answer: Because LDCM/Landsat 8 will deliver data in additional bands, the combinations used to create RGB composites will be different than Landsat 7 and Landsat 5 data bands. For instance, bands 4, 3, 2 are used to create a Color Infrared (CIR) image using Landsat 5 or Landsat 7. To create a CIR composite using LDCM/Landsat 8 bands, bands 5, 4, 3 will be used. The graph below shows the wavelengths from both Landsat 7 (bottom row) and LDCM/Landsat 8. Seeing where the bands fall will help transition to creating LDCM/Landsat 8 RGB composites that will be comparable to Landsat 5 and 7.

15 A few common band combinations in RGB for Landsat 7 and LDCM/Landsat 8 are: Landsat 7 LDCM/Landsat 8 Color Infrared: 4, 3, 2 5,4,3 Natural Color: 3, 2, 1 4,3,2 False Color: 5,4,3 6,5,4 False Color: 7,5,3 7,6,4 False Color: 7,4,2 7,5,3

16 LDCM Status Update for April 16, 2013 All spacecraft and instrument systems continue to perform normally. Two ascent burns were performed in the last week. On Sunday, April 7, ascent burn No. 3 was conducted. The 56.2-second burn was the longest LDCM burn yet, bringing the satellite within range of its operational orbit. Early Friday morning, April 12, ascent burn No. 4 was performed. This 50.5-second burn delivered LDCM to its operational orbit altitude of 705 kilometers (438 miles). Additionally, an inclination burn was successfully executed on Sunday, Apr. 14, and a trim maneuver was not needed.

17 "After many years in the making, LDCM has reached her final home," said LDCM Project Manager Ken Schwer. During this period, OLI and TIRS imaging have continued. The calibration team continues their trending work to refine the instruments' pre-launch calibration.?

18 Thank you