Copernicus Global Land Operations – Lot 2 Date Issued: 18.10.2018 Issue: I1.10 Copernicus Global Land Operations “Cryosphere and Water” ”CGLOPS-2” Framework Service Contract N° 199496 (JRC) ALGORITHM THEORETHICAL BASIS DOCUMENT WATER BODIES PROBA-V 300M VERSION 1 Issue I1.10 Organization name of lead contractor for this deliverable: VITO Book Captain: I. Reusen (VITO) Contributing Authors: L. Bertels (VITO) D. Wolfs (VITO) Copernicus Global Land Operations – Lot 2 Date Issued: 18.10.2018 Issue: I1.10 Document-No. CGLOPS2_ATBD_WB300m_V1 © C-GLOPS2 consortium Issue: I1.10 Date: 18.10.2018 Page: 2 of 53 Copernicus Global Land Operations – Lot 2 Date Issued: 18.10.2018 Issue: I1.10 Dissemination Level PU Public X PP Restricted to other programme participants (including the Commission Services) RE Restricted to a group specified by the consortium (including the Commission Services) CO Confidential, only for members of the consortium (including the Commission Services) Document-No. CGLOPS2_ATBD_WB300m_V1 © C-GLOPS2 consortium Issue: I1.10 Date: 18.10.2018 Page: 3 of 53 Copernicus Global Land Operations – Lot 2 Date Issued: 18.10.2018 Issue: I1.10 Document Release Sheet Document-No. CGLOPS2_ATBD_WB300m_V1 © C-GLOPS2 consortium Issue: I1.10 Date: 18.10.2018 Page: 4 of 53 Copernicus Global Land Operations – Lot 2 Date Issued: 18.10.2018 Issue: I1.10 Change Record Issue/Rev Date Page(s) Description of Change Release 06.09.2017 All First issue I1.00 I1.00 01.08.2018 All Revision after review meeting I1.10 Document-No. CGLOPS2_ATBD_WB300m_V1 © C-GLOPS2 consortium Issue: I1.10 Date: 18.10.2018 Page: 5 of 53 Copernicus Global Land Operations – Lot 2 Date Issued: 18.10.2018 Issue: I1.10 TABLE OF CONTENTS 1 Background of the document ............................................................................................. 12 1.1 Executive Summary ............................................................................................................... 12 1.2 Scope and Objectives............................................................................................................. 12 1.3 Content of the document....................................................................................................... 12 1.4 Related documents ............................................................................................................... 12 1.4.1 Applicable documents ................................................................................................................................ 12 1.4.2 Input ............................................................................................................................................................ 12 1.4.3 Output ......................................................................................................................................................... 13 1.4.4 External Documents .................................................................................................................................... 13 2 Review of Users Requirements ........................................................................................... 14 3 Methodology Description .................................................................................................. 16 3.1 Overview .............................................................................................................................. 16 3.2 The retrieval Algorithm ......................................................................................................... 17 3.2.1 Outline ........................................................................................................................................................ 17 3.2.2 Basic underlying assumptions ..................................................................................................................... 19 3.2.3 Related and previous applications .............................................................................................................. 19 3.2.4 Alternative methodologies currently in use ............................................................................................... 21 3.2.5 Input data.................................................................................................................................................... 21 3.2.6 Output product ........................................................................................................................................... 25 3.2.7 Methodology............................................................................................................................................... 26 3.2.8 Limitations .................................................................................................................................................. 51 3.3 Quality Assessment ............................................................................................................... 52 3.4 Risk of failure and Mitigation measures ................................................................................. 52 4 References ........................................................................................................................ 53 Document-No. CGLOPS2_ATBD_WB300m_V1 © C-GLOPS2 consortium Issue: I1.10 Date: 18.10.2018 Page: 6 of 53 Copernicus Global Land Operations – Lot 2 Date Issued: 18.10.2018 Issue: I1.10 List of Figures Figure 1: General overview of the Water Bodies Detection Algorithm. .......................................... 16 Figure 2: Outline of the Water Bodies Detection Algorithm. ........................................................... 18 Figure 3: Location in Northern South-Sudan (10°0’N, 31°80’E). a) False water bodies were detected because of dark soils. b) By applying the extra check on the MWEM most of the commission errors could be prevented. .................................................................................. 20 Figure 4: Location in Southern Spain (38°40N, 7°4’W). a) Due to the strict Water Bodies Potential Mask parts of the lake were not detected as water. b) The MWEM overrules the WBPM and as such reduces the omission errors. ......................................................................................... 21 Figure 5: a) This Google Earth image shows an area over the Alps (Upper left corner: 48°08’25” N, 5°40’0” E). b) The permanent glacier mask for the same area in (a). ..................................... 23 Figure 6: a) Google Earth image showing part of northern Ethiopia and southern Eritrea with the dark volcanic soils manually delineated (red polygons). b) Dekad MC10_20140521 for the same area with the derived dark volcanic soils shape file overlaid. c) The final volcanic soil mask (white=volcanic soil) obtained after rasterizing the shape file. ....................................... 24 Figure 7: a) The high resolution Maximum Water Extent product of JRC’s Global Surface Water dataset shows where in the last 32 years water was ever detected (blue colored). b) The PROBA-V 300 m resolution Maximum Water Extent Mask is derived from the Maximum Water Extent product of JRC’s Global Surface Water dataset. Both images have the PROBA-V 300 m raster overlaid (red). The shown water reservoir is located in India (25°25’N, 77°55’E). ..... 25 Figure 8: MC10 algorithm flow. ..................................................................................................... 28 Figure 9: Decision tree for MC10 observation type classification. .................................................. 29 Figure 10: a) Part of the 90 m spatial resolution GLSDEM over Rift Valley in Ethiopia. b) The detected lowest points for this area are colored yellow. The larger sized colored areas are areas of equally low elevation which correspond to some smaller lakes in the region. ........... 31 Figure 11: Expanding the initially detected lowest point by systematically rising an imaginary water level in steps of 1 m. The corresponding 90 m spatial resolution pixels are indicated by the dots at the bottom. ................................................................................................................. 32 Figure 12: a) Part of the GLSDEM over Rift Valley. b) The detected potential WBs for this area. The detailed window shows a potential WB in the center (crossing of red lines). The horizontal and vertical profiles are according to the red lines over the images. On the horizontal profile, the wetland (1) near lake Hora (2) and the potential water body (indicated by the long red arrow) are seen. On the vertical profile part of the wetland (1’) near lake Hora (2), the potential water body (indicated by the long red arrow) and lake Bishoftu (3) are seen. ......................... 33 Figure 13: a) Part of image MC10_20131021 taken over the Rift Valley in Ethiopia (SWIR, NIR and Red bands assigned to the RGB channels resp.). b) The WBPM for the same area in (a) Document-No. CGLOPS2_ATBD_WB300m_V1 © C-GLOPS2 consortium Issue: I1.10 Date: 18.10.2018 Page: 7 of 53 Copernicus Global Land Operations – Lot 2 Date Issued: 18.10.2018 Issue: I1.10 (white=potential water body, black=no water body possible). The plot shows the vertical GLSDEM profile according to the red line. Marked with the blue boxes are the seven potential WBs. The arrows indicate the location of lake Abijato (1) and lake Langano (2). ................... 35 Figure 14: The HSV color space. .................................................................................................