Coastal adaptation measures must consider both sea level rise and extreme sea levels

A scientist specialising in coastal risks and climate change at the University of Southampton, UK, has reported that, while our understanding of sea level rise is growing, further information is needed about extreme sea levels—effects due to storm surges, high tides, and waves.

Our understanding of the impact of sea level rise on flood risk is growing. In fact, recent results are quite shocking. For the US coast, Buchanan et al (2017) concluded that events that currently have a one per cent chance of occurrence in any given year (so-called 100 year events) may occur 25 times as often by 2050 under a moderate scenario of climate change, and 40 times as often under a high-end scenario. They also pointed at different impacts of sea level rise on the occurrence of relative frequent (moderate) and rare (extreme) flood events: On the east coast, cities like Charleston or New York will experience a strong increase in the number of moderate events, while a city like Seattle on the west coast will experience a more rapid increase in the number of rare extreme events.

Climate Change Post summarised this study in their article ‘Current once-in-a-hundred-years flood levels along US coastline may occur every few years by 2050’. Similar results were shown in a study by Vitousek et al (2017), summarised in Climate Change Post’s article ‘Just a few cm of sea level rise may double the frequency of coastal flooding’.

Sea level rise, however, is a gradual process that can be anticipated. Extreme sea levels due to storm surges, high tides, and waves, on the other hand, occur randomly and accurate forecasts become only available a few days or hours before the impacts occur. Recent events like Hurricanes Harvey and Irma have revealed how vulnerable and ill-prepared many coastal communities are for such extreme events. Therefore, adequate adaptation has to take into account sea level rise and extreme sea levels as well as the uncertainties inherent to both of them.

Little is known about future extreme sea levels at continental and global scales. In the IPCC assessments, for instance, a lot of information is presented on sea level rise but the information on extreme sea levels is limited. Uncertainties in these extremes are at least as important as uncertainties in projections of sea level rise. Hence, both these contributions to flood risk need to be integrated to fully assess impacts and adaptation needs.

Future changes in storm surges may add to sea level rise or damp the effects of sea level rise. According to a study by Vousdoukas et al (2016) projected storm surge changes strongly vary along Europe’s coastline: An increase in Northern Europe, no change or a slight decrease in the South (summarised in the article ‘Storm surge levels increase along Northern Europe’s coastline’).

Thus, recent studies point at strong impacts of both sea level rise and storm surge on flood frequency, that strongly vary along the US or Europe’s coastline, and the combined effect of which is highly complicated. Clearly, these combined impacts need to be accounted for in coastal management and adaptation plans.

The article first appeared on Climate Change Post and is a digest of a scientific paper by Wahl, 2017. Environmental Research Letters 12.

 
Articles you may be interested in
In The News
Four EIT Climate-KIC innovators nominated for annual EIT Awards

The European Institute of Innovation and Technology (EIT) has released...

Four EIT Climate-KIC innovators nominated for annual EIT Awards
In Detail
Report offers recommendations for development of agricultural impact tool

A new report supported by EIT Climate-KIC’s CSA Booster programme proposes technical, governance and business arrangements for the development of a new tool for...

Report offers recommendations for development of agricultural impact tool
In Detail
Food value chains strategy report offers recommendations based on systemic i...

A new report details the work of EIT Climate-KIC and its partner Metabolic, a consulting company using systems thinking to tackle major sustainability challenges,...

Food value chains strategy report offers recommendations based on systemic impact
In The News
EIT Climate-KIC supports digital roadmap for a circular economy

EIT Climate-KIC, along with several European stakeholders, is advocating...

EIT Climate-KIC supports digital roadmap for a circular economy
In The News
EIT Climate-KIC urges London to lead in turning climate emergency into action

Climate innovation agency EIT Climate-KIC welcomed today the first...

EIT Climate-KIC urges London to lead in turning climate emergency into action
Opinion
London Climate Action Week: Climate Innovation Insights
London Climate Action Week: Climate Innovation Insights
Opinion
How can we deliver a net-zero emissions UK?
Andy Kerr Director, UK & Ireland, EIT Climate-KIC
How can we deliver a net-zero emissions UK?
Opinion
Can we identify the tipping points for transformative climate action?
Susannah Fisher Strategic Research Lead, EIT Climate-KIC
Can we identify the tipping points for transformative climate action?
In The News
Study launched on decarbonising Europe’s heavy industries by 2050

Industry representatives, regional experts, academics and EU officials held...

Study launched on decarbonising Europe’s heavy industries by 2050
In our community
Interview with Yvon Slingenberg of DG Climate Action, European Commission
Interview with Yvon Slingenberg of DG Climate Action, European Commission
In Detail
Evaluating the benefits of improved cooking solutions: impact data in high r...

Gold Standard today released a research study by Vivid Economics that estimates the economic value of Gold Standard-certified project benefits related to climate, health,...

Evaluating the benefits of improved cooking solutions: impact data in high resolution
In The News
New EIT Climate-KIC supported report proposes basis for a future EU taxonomy i...

The European Commission has welcomed the publication of the...

New EIT Climate-KIC supported report proposes basis for a future EU taxonomy in legislation
In The News
WCEF 2019: The challenges and potentials of circular procurement in cities

Increasing population growth and urbanisation intensifies the pressure on...

WCEF 2019: The challenges and potentials of circular procurement in cities
In The News
First round of 15 winners of Reinventing Cities competition announced

C40 Cities and EIT Climate-KIC have announced 15 winners...

First round of 15 winners of Reinventing Cities competition announced
In The News
Lisbon’s City Finance Lab-backed green participatory budget awarded €5 mil...

Lisbon City Council’s first-ever ‘green’ participatory budget, an initiative...

Lisbon’s City Finance Lab-backed green participatory budget awarded €5 million for next cycle
In The News
WCEF 2019: ‘The circular economy in cities’

EIT Climate-KIC CEO Kirsten Dunlop emphasised the importance of...

WCEF 2019: ‘The circular economy in cities’
In Detail
New Report on Circular Procurement in public construction projects shows how...

Public procurement affects a substantial share of world trade, amounting to more than €1.3 trillion per year. In the EU, the public purchase of...

New Report on Circular Procurement in public construction projects shows how targeted action can drive system-level impact
In The News
EIT Climate-KIC at World Circular Economy Forum 2019

EIT Climate-KIC is playing a prominent role at the...

EIT Climate-KIC at World Circular Economy Forum 2019
In The News
17 EIT Climate-KIC solutions included in MI 100 Global High Impact listing

13 EIT Climate-KIC Accelerator start-ups and four EIT Climate-KIC...

17 EIT Climate-KIC solutions included in MI 100 Global High Impact listing
In The News
EIT Climate-KIC’s global cleantech competition ClimateLaunchpad is open ...

EIT Climate-KIC’s ClimateLaunchpad, the world’s largest green business ideas...

EIT Climate-KIC’s global cleantech competition ClimateLaunchpad is open for registration
Opinion
Transformation Capital: A new investment logic for catalysing systems change
Dominic Hofstetter Transformation Capital, EIT Climate-KIC
Transformation Capital: A new investment logic for catalysing systems change
In The News
EIT Climate-KIC supported SkyNRG develops Europe’s first sustainable jet...

SkyNRG announced plans to develop Europe's first sustainable aviation...

EIT Climate-KIC supported SkyNRG develops Europe’s first sustainable jet fuel production plant
Opinion
Collaboration is hard!
Ulrike Linnig Innovation Lead, DACH, EIT Climate-KIC
Collaboration is hard!
In The News
EIT Climate-KIC supported report shows how to reduce industrial CO2 emissions

A new joint report, published by RWTH Aachen University...

EIT Climate-KIC supported report shows how to reduce industrial CO2 emissions
In The News
London event showcases innovation behind new investor climate tool

Yesterday’s event, titled “Applying Climate Risk Data to Investment...

London event showcases innovation behind new investor climate tool
In our community
Interview with Francisco de la Torre, Mayor of Malaga, Spain
Interview with Francisco de la Torre, Mayor of Malaga, Spain
Opinion
Adapting to climate change in Europe: Building a systemic and urgent vision
Susannah Fisher, EIT Climate-KIC and Andrew Norton, IIED
Adapting to climate change in Europe: Building a systemic and urgent vision
In our community
Interview with Andrzej Wiszniewski, President of the Board, National Energy ...
Interview with Andrzej Wiszniewski, President of the Board, National Energy Conservation Agency Poland
In The News
FEED-X programme aims to transform global feed industry

Supported by EIT Climate-KIC, global feed supplier Skretting, WWF...

FEED-X programme aims to transform global feed industry
In The News
New reports say net-zero emission EU heavy industry by 2050 is achievable

Achieving net-zero emissions by 2050 for European energy-intensive industries...

New reports say net-zero emission EU heavy industry by 2050 is achievable