Scientific report ; WR 2009-05 Exploring high-end climate change scenarios for flood protection of the Netherlands Pier Vellinga, Caroline Katsman, Andreas Sterl, Jules Beersma, Wilco Hazeleger, John Church, Robert Kopp, Dick Kroon, Michael Oppenheimer, Hans-Peter Plag, Stefan Rahmstorf, Jason Lowe, Jeff Ridley, Hans von Storch, David Vaughan, Roderik van de Wal, Ralf Weisse, Jaap Kwadijk, Rita Lammersen and Natasha Marinova De Bilt, 2009 KNMI scientific report = wetenschappelijk rapport; WR 2009-05 De Bilt, 2009 PO Box 201 3730 AE De Bilt Wilhelminalaan 10 De Bilt The Netherlands http://www.knmi.nl Telephone +31(0)30-220 69 11 Telefax +31(0)30-221 04 07 © KNMI, De Bilt. All rights reserved. No part of this publication may be reproduced, stored in retrieval systems, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior permission in writing from the publisher. zzzz Exploring high-end climate change scenarios for flood protection of the Netherlands International Scientific Assessment carried out at request of the Delta Committee The Netherlands, September 2008 Pier Vellinga, Caroline Katsman, Andreas Sterl, Jules Beersma, Wilco Hazeleger, John Church, Robert Kopp, Dick Kroon, Michael Oppenheimer, Hans-Peter Plag, Stefan Rahmstorf, Jason Lowe, Jeff Ridley, Hans von Storch, David Vaughan, Roderik van de Wal, Ralf Weisse, Jaap Kwadijk, Rita Lammersen, Natasha Marinova This scientific report is a joint publication by Wageningen University and Research Centre / Alterra and the Royal Netherlands Meteorological Institute (KNMI) - 1 - - 2 - Author Team Convening author/ editor Pier Vellinga1 Introduction and Main findings Pier Vellinga1, Natasha Marinova1, Wilco Hazeleger2, Caroline Katsman2, Andreas Sterl2, Jules Beersma2 Chapter I - High-end projection for local sea level rise along the Dutch coast in 2100 and 2200 Caroline Katsman2, John Church3, Robert Kopp4, Dick Kroon56, Michael Oppenheimer4, Hans-Peter Plag7, Stefan Rahmstorf8, Jeff Ridley9, Hans von Storch10, David Vaughan11, Roderik van der Wal12 Thanks to: Catia Domingues3, Sybren Drijfhout2, Wilco Hazeleger2, Simon Jung5, Simon Tett5, Bert Vermeersen13, Neil White3 Chapter II - Winds and storm surges along the Dutch coast Andreas Sterl2, Ralf Weisse9, Jason Lowe8, Hans von Storch9 Thanks to: Hans de Vries2, Henk van den Brink2, Reindert Haarsma2, Erik van Meijgaard2 Chapter III - River Rhine discharge Jules Beersma2, Jaap Kwadijk14 and Rita Lammersen15 Thanks to: Adri Buishand2, Hendrik Buiteveld14, Alexander Bakker2, Albert Klein Tank2, Nick Raynard16 Addendum - Sea level rise in foreign policy documents Natasha Marinova1 1 Alterra, Wageningen University and Research Centre, the Netherlands 2 Royal Netherlands Meteorological Institute (KNMI), the Netherlands 3 Centre for Australian Weather and Climate Research, A partnership between CSIRO and the Bureau of Meteorology, and the Antarctic Climate and Ecosystems CRC 4 Woodrow Wilson School of Public and International Affairs and Department of Geosciences, Princeton University, USA 5 School of GeoSciences, University of Edinburgh, West Mains Road, Edinburgh, Scotland 6 Vrije Universiteit, Amsterdam, the Netherlands 7 Nevada Bureau of Mines and Geology and Seismological Laboratory, University of Nevada, Reno, USA; 8 Potsdam Institute for Climate Impact Research, Germany 9 Hadley Centre for Climate Prediction and Research, Met Office, UK 10 GKSS Research Center, Institute for Coastal Research, Germany 11 British Antarctic Survey, Natural Environment Research Council, UK 12 Institute for Marine and Atmospheric Research, Utrecht University, the Netherlands 13 Delft University of Technology, the Netherlands 14 Deltares, the Netherlands 15 Rijkswaterstaat Waterdienst, the Netherlands 16 Centre for Ecology and Hydrology, Wallingford, UK - 3 - - 4 - Table of Contents Synthesis of the main findings ................................................................... 13 High-end projections for sea level rise...........................................................13 Storminess................................................................................................13 River Rhine discharge .................................................................................14 CHAPTER I – High-end projection for local sea level rise along the Dutch coast in 2100 and 2200 .............................................................................. 15 1. Introduction ........................................................................................... 15 1.1. Factors influencing local sea level...........................................................15 1.2. Uncertainties involved in projecting future local sea level...........................16 2. Sea level rise in the twenty-first century................................................ 17 2.1 IPCC AR4 projections for global mean sea level rise ...................................17 2.2 High-end contributions to global mean sea level rise..................................18 2.3 High-end projection for global mean sea level rise in 2100 .........................23 2.4 Local sea level changes .........................................................................25 2.5 High-end projection for sea level rise along the Dutch coast in 2100 ............28 3. Sea level rise in the twenty-second century ........................................... 30 3.1 Global mean thermal expansion ..............................................................31 3.2 Small glaciers ......................................................................................31 3.3 Ice sheets............................................................................................32 3.4 Plausible high-end scenario for global mean sea level rise for 2200..............33 3.5 Plausible high-end scenario for sea level rise at the Dutch coast for 2200 .....34 4. Conclusions and recommendations......................................................... 35 4.1 Conclusions .........................................................................................35 4.2 Recommendations ................................................................................36 5. Scientific background ............................................................................. 37 5.1 Observed local sea level changes along the Dutch coast .............................37 5.2 High-end scenario for atmospheric temperature rise for 2100 .....................40 5.3 Global mean thermal expansion ..............................................................40 5.4 Ice sheets............................................................................................45 5.5 Paleo-climatological perspective..............................................................57 Appendix I-a: Thermosteric sea level sensitivity ................................................65 Appendix I-b: Marine ice sheet instability .........................................................69 References ...................................................................................................72 CHAPTER II - Winds and storm surges along the Dutch coast ................... 82 Abstract...................................................................................................... 82 1. Introduction .......................................................................................... 82 2. Past and future changes of near-surface marine wind fields .................. 83 - 5 - 2.1 Past changes / Variability.......................................................................83 2.2 Projections ..........................................................................................83 2.2.1. IPCC ............................................................................................83 2.2.2 Regional climate modelling – PRUDENCE ............................................84 2.2.3 Global climate modelling – Essence ...................................................87 3. Projected changes of local storm surges ................................................ 90 3.1. Approach............................................................................................90 3.2. Uncertainty.........................................................................................91 3.3. Regional climate modeling ....................................................................92 3.4 Results from Essence ............................................................................93 4. Projected change of wind waves ............................................................ 93 5. Summary and discussion ........................................................................ 94 References ...................................................................................................95 CHAPTER III - Effects of climate change on the Rhine discharges ............. 99 1. Introduction ........................................................................................... 99 1.1. Objectives ..........................................................................................99 1.2. Main results ........................................................................................99 2. The hydrology of the Rhine basin ......................................................... 100 3. Methods used to assess future discharge changes of the River Rhine . 101 3.1 Delta approach................................................................................... 103 3.2 Direct approach.................................................................................