Landsat: 43+ Years of Global Land Observation

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1 Landsat: 43+ Years of Global Land Observation Landsat 1 launched July 1972 (MSS) Landsat 2 launched January 1975 (MSS) Landsat 3 launched March 1978 (MSS) (80m res. No MIR) Landsat 4 launched July 1982 (TM) (30m res. Inc. MIR) Landsat 5 launched March 1984 (TM) Landsat 6 launched October 1993 failed shortly after Landsat 7 launched April 1999, May 2003 SLC-Off (ETM+) Landsat 8 launched February 2013 (OLI)

2 Landsat image, Zermatt 01/09/2010

3 Landsat is special. Landsat is one of 73 satellite-based global land observing programs operated by 34 different sovereign states (Belward & Skøien, 2015), but. Landsat-1 was the first near polar orbiting satellite observing the Earth's landmass The Landsat archive was the first to offer free global imagery (at 30 m resolution) since 2008

4 Landsat data the basis for > 2x refereed papers dealing with land cover than any other system At 28 years of operation, Landsat-5 operating for almost twice as long as any other Earth observing satellite (and there have been more than 200)

5 Multi Spectral Scanner (1972) LANDSAT (U.S.) initially known as ERTS 1972 Landsat 1 Multi-Spectral Scanner (MSS: 80m) 1975 Landsat 2 until Landsat 3 until 1983 No Mid-IR band(s).

6 Landsat TM ( ) bands mostly Landsat Landsat 4 Thematic Mapper (TM: 30m) until Landsat 5 TM... Operational till 2011

7 Enhanced Thematic Mapper Plus (ETM+) (Landsat 7): Additional band versus Landsat 5 TM: PAN (Green->IR) band 15m [and the Thermal band is 60m versus 120m for Landsat 5] Sensor malfunctionned, April 2003 (Scan Line Calibration) Landsat 7 data ( ) used for Google Earth and Google maps mosaics

8 Landsat 7 Still receiving ~500 scenes / day useful data if the Force is with you Minimum striping Possible to combine multiscenes

9 Landsat 8 successfully launched February 2013

10 EO-1 launched November 2000: ALI Covering earth 1 minute after Landsat 7 Advanced Land Imager testing new technology for future Landsats Pushbroom versus Whiskbroom; (fewer moving parts ) 3 extra bands + PAN (10m); 16 bit data (0-65,535)

11 Landsat 8: Operational Land Imager

12 Landsat 8, first image: Fort Collins, CO 432 composite

13 Landsat Data Continuity Mission (LDCM) 753 composite

14 Aral Sea, OLI colour composite

15 Aral Sea, OLI cirrus band

16 Comparison of Landsat 8 OLI bands and 7 ETM+ bands

17 Landsat 8 Thermal data TIRS bands 10-11: collected at 100 meters but resampled to 30 meters to match OLI multispectral bands

18 Both OLI and TIRS generate 12 bit data (0-4095) Scaled to -> 16 bit (0-55,000 grayscales ) 8 bit = bands 12-bit (including 1 at 15m) v 7 bands 8-bit data Data Delivery:.tar.gz compressed file size: ~1 GB (compressed), ~2 GB (uncompressed) Universal Transverse Mercator (UTM) map projection - Polar Stereographic for scenes with center > 63 N/S World Geodetic System (WGS) 84 datum

19 Why do we need 12 or 16 bit data? Advantages: improved characterization of land cover reduced saturation e.g. snow / ice more detail in water / shadows Drawbacks: Landsat 5 TM Landsat 8 OLI Not required for many applications? Need to extra enhance to avoid black (GIS) Need to re-tweak ratio thresholds Higher data volume

20 Landsat 5 TM visible bands dashed = human eye sensitivity

21 Landsat 8 OLI visible bands note new band 1

22 The global Landsat archive: Status, consolidation, and direction Remote Sensing of Environment Mike Wulder et. Al 2015 Canadian Forest Service, Victoria, BC, V8Z 1M5, Canada

23 Landsat ground receiving stations Landsat 1-5: data captured only by stations with receiving area - International Co-operators nations Some ICs switched from L5 to L7 after 1999, but switched back after May 2003 At one time, MDA built 27 of world s 32 stations

24 Landsat archive Jan 2015

25 Contributed by coorperators

26 Still to be added to archive

27 USGS Archive Jan 2015 Sensor #images (m) archive (TB) image (MB) Years Annual acquisition rate MSS ,652 TM ,388 ETM ,135 OLI 400k ,081 Total Current acquisition rate (L8) : ~725 images per day

28 LANDSAT Sequence - Kumtor gold mine, Kyrgyzstan, 1975

29 Kumtor gold mine, Kyrgyzstan, 1998

30 Kumtor gold mine, Kyrgyzstan, 2006

31 Kumtor gold mine, Kyrgyzstan, 2013

32 Kumtor is 100% owned by the Canadian mining company, Centerra Gold. The mine started operation in 1997 and produced more than 5.8 million ounces (180,000 kg) of gold through the end of However, in mid June 2012, the Kyrgyz Parliament issued a resolution to review Kumtor s compliance with relevant operational, environmental, health and safety and community standards.