COASTAL VULNERABILITY DUE TO SEA-LEVEL RISE HAZARDS IN THE BANGLADESH DELTA: BAND-AID

Band-Aid Project NASA NASA ESA ESA JAXA NASA/DLR COASTAL VULNERABILITY DUE TO SEA-LEVEL RISE HAZARDS IN THE BANGLADESH DELTA: BAND-AID R. Rietbroek, B. Uebbing, C.K. Shum, V. Ballu, S. Calmant, J. Duan, J. Guo, F. Hossain, C. Jenkins, Z. Haque Khan, J. Kim, M. Kuhn, J. Kusche, F. Papa, K-H Teng, J. Wan, B. Braun, A. Bernzen, R. Ahmed, and M. Hossain LIVELIHOOD RESILIENCE, RESEARCH, AND PRACTICE BONN, 26 JUNE, 2015 Partner: Bonn University, Germany Ohio State Univ., US IRD, France Inst. For Water Modelling, Dhaka, BD University of Cologne, Germany Curtin University, Perth, AUS LEGOS, Toulouse, France Univ. of Rajshai, Rajshahi, BD

Band-Aid Project BELMONT FORUM PROJECT: BANGLADESH COASTAL VULNERABILITY & SEA-LEVEL RISE HAZARDS, BAND-AID Ganges Brahmaputra-Meghna Delta (Bay of Bengal, Bangladesh) is the largest Delta and one of the most densely population regions in the world 3 Bangladesh is prone to transboundary monsoonal flooding, storm surges, and climate change induced sea-level rise. Land subsidence caused by tectonics, sediment load and ground water extraction have exacerbate the risks for Bangladesh s coastal vulnerability Objectives: (1) establish a satellite geodetic observational system to quantify sea-level rise and land motion in the Delta, and to project relative sea-level rise to 2100 and beyond, at fine regional scales, and (2) to quantify the human interaction and social sciences that govern coastal vulnerability in Bangladesh

20th century global mean sea level rise 4 Tide gauge trend ~1.6-1.8 mm/year

Sea level rise is not uniform 5 Mean: 3mm/a

Sea level rise is not uniform 6 Mean: 3mm/a BoB: 6 mm/a

What are the issues adressed in Band-Aid 7 Bangladesh Assessment of SLR (~6 mm/y) and physical/social implications

What are the issues adressed in Band-Aid Himalaya and upstream Monsoonal changes 8 Sea level rise Floodings, surges and cyclones Salinization Tides and coastal morphology Vertical land motion Sedimentation Bangladesh Assessment of SLR (~6 mm/y) and physical/social implications Land use (agriculture, shrimp farming, reservoir construction) Tidal river management Coastal embankment strategies

Satellite-geodetic observational system 9

Climate variability and ocean heat uptake 1993-2014 2003-2014 10 mm/a low-lying (<10m) Currently, sea level rise is accelerating along many coast of South Asia. A part of this is natural variability; i.e. it will not continue. But what part?

Sea level Projections 2050 11 Polders in green. Nonlinear (accelerated) sea-level projection based on climate scenarios [Parris et al. 2012; Vermeer & Rahmstorf, 2009] & reconstructed sea-level trend, 1950 2012 [Meyssignac et al., 2012] & GPS subsidence [Steckler et al., 2012; courtesy]

Sea level Projections 2050 2100 12 Polders in green. Nonlinear (accelerated) sea-level projection based on climate scenarios [Parris et al. 2012; Vermeer & Rahmstorf, 2009] & reconstructed sea-level trend, 1950 2012 [Meyssignac et al., 2012] & GPS subsidence [Steckler et al., 2012; courtesy]

Sea level Projections 2050 13

Relative sea level and its measurement 2050 14 Land subsidence is as important as sea level rise. Long-term monitoring (vertical control, tide gauge, geodetic network) very important!

Relative sea level and its measurement Bangladesh is a polder country, strong tides and morphology changes. 2050 Long-term terrestrial monitoring along the coast is difficult and expensive. 15 Coastal embankment improvement project.

Regional sea level rise 1st project meeting, Dhaka 2014 17 Tide gauge station installed by Band-Aid

Connecting satellite and tide gauge measurements S. Calmant (IRD) 18 Measuring sea level with a GPS float for calibrating satellite measurements

Band-Aid Project Sustainable Research Close cooperation with local partners (IWM, others Capacity building (e.g. training workshop 8/2015) Seek to engage in long-term collaboration 19