From ice to high seas: The changing risk of coastal flooding around the world Prof. David Vaughan OBE Director of Science Accompanied by: Dr Simon Morley Mr Paul Hayden Mauritius State House 22 May, 2017

What is British Antarctic Survey?

British Antarctic Survey SWOT analysis

British Antarctic Survey Delivering research at both poles Delivering scientific advice to UK government Provides operational support to UK polar science Delivering excellent BAS core- and grant-funding from NERC is supplemented by EU and other grants Active programme of national and international science collaborations SWOT analysis

BAS - vision To be a world-leading centre for polar science and polar operations, addressing issues of global importance and helping society adapt to a changing world “A partner of choice for science, operations and business wherever polar expertise can be applied”

BAS Supporting polar science Headquarters in Cambridge 5 Antarctic research stations 1 Arctic research station Deep-field facilities 2 polar ships 5 polar aircraft SWOT analysis

David Vaughan Fieldwork in Antarctica 1980s Serving on Intergovernmental Panel on Climate Change 2013

Why are we here?

South Atlantic Island fisheries 80% of Tristan da Cunha income from the commercial lobster fishery St Helena fish is the major export and the major income stream after aid Photo: Maurits Heech / Flickr

Water resources of the Upper Indus High Mountain Asia has the highest concentration of mountain glaciers in the world Important to note that this follows several years of work in these areas, during which we have adapted instruments that we developed for the Antarctic into ones that will work in High Mountain Asia. 300 Million people in Indus Region Photo: ICIMOD Kathmandu Photo: ICIMOD Kathmandu

Water resources of the Upper Indus “Glaciers are a regionally-important buffer against drought” Important to note that this follows several years of work in these areas, during which we have adapted instruments that we developed for the Antarctic into ones that will work in High Mountain Asia. 300 Million people in Indus Region Pritchard, Nature. May, 2017 Photo: ICIMOD Kathmandu

Why are we here in Mauritius? During the visit To learn more about the Strategic requirements of Mauritius To identify areas where BAS / NERC science may be able support Mauritius After the visit Share with the NERC community Identify potential areas for future partnership Important to note that this follows several years of work in these areas, during which we have adapted instruments that we developed for the Antarctic into ones that will work in High Mountain Asia. 300 Million people in Indus Region Photo: ICIMOD Kathmandu

Potential areas for discussion Baseline assessment of marine ecosystems Ecosystem-based fisheries management Ground-water monitoring Sea-bed and topographic mapping Climate-change impacts assessment … Important to note that this follows several years of work in these areas, during which we have adapted instruments that we developed for the Antarctic into ones that will work in High Mountain Asia. 300 Million people in Indus Region Photo: ICIMOD Kathmandu

Ice and sea-level

Contributions to sea-level change

Recent observed global sea-level rise 3.2 mm/year 2.0 mm/year Satellites 0.8 mm/year Tide gauges Source – Steve Nerem 16

Regional sea-level rise 1993-2012 Source: NOAA -9 0 9

Impacts of sea-level rise

Unique coastal ecology e.g. “Machair” in Ireland and Scotland Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: Alison Cook

Coastal investment e.g. Sizewell B Nuclear Power Station (England) Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: William Connolley

Major coastal cities e.g. Rotterdam Photo: GoogleEarth Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: GoogleEarth

Changing risk

Vulnerable areas 1 metre above highest normal tide Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Courtesy: CRESIS - Kansas 1 metre above highest normal tide

London - coastal vs. river flooding Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: UK Environment Agency

Responsive development of flood defences 1953 flood interim defences 1930 Flood Act Late-C19 update to Flood Act 1879 Flood Act Photo: UK Environment Agency Trinity Hospital Greenwich

100th closure of the Thames Barrier Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: UK Environment Agency

100th closure of the Thames Barrier Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: UK Environment Agency

Isle of Harris (Scotland) Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: Alison Cook

The glacial contribution to sea-level rise

World of glaciers Randolph Glacier Inventory = 198,000 glaciers SWOT analysis Randolph Glacier Inventory = 198,000 glaciers

Two ice sheets Antarctica and Greenland 11% of land area Annual flux of 6 mm a-1 of global sea level Response time 100-10000 years SWOT analysis

Bed elevation in Greenland and Antarctica Thinning rates 2003-2007 Pritchard et al., 2009 – Nature, 23 September 2009

Current sea-level projections

IPCC AR5 (2013/14) on sea-level rise

Closing the budget in Global Mean Sea Level 1993-2010 Data from Table 13.1 IPPC AR5 SWOT analysis Randolph Glacier Inventory = 198,000 glaciers

Projections of 21st-century Global temperature CMIP5 multi-model time series from 1950 to 2100 relative to 1986–2005 Rate comparable to deglaciation. Say what it would be without Ant ppn increase. With rcp26 you get a constant rate of rise, not zero rise. 1950 2000 2050 2100 SPM Fig 6

Projections of 21st-century GMSLR under RCPs Medium confidence in likely ranges. Very likely that the 21st-century mean rate of GMSLR will exceed that of 1971-2010 under all RCPs. (Compared to ice2sea “best estimate” for A1B, including AR4 thermal expansion 0.16 – 0.69 m) Rate comparable to deglaciation. Say what it would be without Ant ppn increase. With rcp26 you get a constant rate of rise, not zero rise. SPM Fig 8

Questions stakeholders ask

Unique coastal landscapes Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: QRT300

Corpus Christi - Texas Photo: Karen “The Brit_2” – flickr Moving from Flood Defence to Flood Risk Management. Flood Risk = Probability (which decreases as increasingly large defences are built) X Consequence (which increases as people move in and develop behind the defences) We are used to the concept of probability (likelihood) of flooding and it can be measured fairly easily. Consequence is more difficult and our studies are enabling us to measure the risk and the value of reducing the consequence through flood risk management measures within the flood plain. These are known as “Receptor” responses. Photo: Karen “The Brit_2” – flickr

Combined high-end estimates for 2100 changes in extreme 50-year storm height Storm surge climate Ice-induced ocean dynamics Ice melt Thermal exp + non-ice ocean dynamics Vertical land movement

Specific questions asked by policy-makers Maximum rates of sea-level rise Low-probability high-impact scenarios of sea-level rise vs. “best-estimate” Local impacts (subsidence/emergence) Sea-level vs. storm surge Photo: ICIMOD Kathmandu

Thank you for your attention