State of the Art Science

Sea-level rise is an existential threat to coastal residents around the world as it progressively raises water levels, promoting increased flooding, erosion, salinization and ecosystem loss and degradation. Small islands, deltas and coastal cities are particularly threatened. Future sea-level rise is deeply uncertain with the worst scenarios of rise linked to the great ice sheets of Greenland and Antarctica and their response to global warming. Unmitigated climate change will lead to rapidly accelerating rise with a metre of rise by 2100 appearing likely and larger rises possible. Once initiated, sea levels would continue to rise for many centuries with catastrophic consequences. Hence, climate mitigation is critical. However, even the climate mitigation and temperature stabilisation targets agreed in the Paris Agreement will slow but not stop climate-induced sea-level rise due to the long timescales of ocean and ice sheet response to warming. Hence, sea-level rise is expected to continue slowly for centuries, even if the Paris Agreement is fully implemented.

Building on the success of the Sea Level 2017 Meeting in New York, the World Climate Research Program (WCRP) Grand Challenge on “Regional Sea-Level Change and Coastal Impacts” will hold the Sea Level 2022 meeting in Singapore. It will assess the current understanding of these challenges and what actions and approaches in both the science and adaptation practitioner domains are needed to meet them. The meeting comes three years after the publication of the IPCC Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC) and one year after the publication of the new IPCC WG1 AR6 report, providing a good moment for reflection. Sea Level 2022 will critically assess the different components of sea-level change to understand their likely magnitude under the range of possible emissions over the 21st Century and beyond. It will also consider the key uncertainties that need to be addressed in future research with a view towards AR7 and beyond. Given the critical need for coastal adaptation it will also consider how to effectively make this information available and most useful to the coastal policymakers and practitioners engaged in risk assessment and adaptation, drawing on contributions from practitioners engaged in adaptation planning today.

 The conference is held in a region where sea-level rise is an existential threat. Singapore is an island where one third is below 5 m above mean sea level today. More broadly, south, south-east and east Asia contain most of the world’s vulnerable coastal population and the needs for coastal adaptation are immense. Hence, information on future sea levels is critical for coastal development, adaptation and planning. Sea Level 2022 is a global conference engaged with the world community, but it recognises a particular need to benefit these vulnerable populations in Asia and other settings such as deltas and small islands.

 In summary, Sea Level 2022 will consider:

  •       The key uncertainties in sea-level science and how they can be addressed;
  •       The requirements that risk and adaptation assessment raise for sea-level science;
  •       How to sustain an ongoing science-practitioner dialogue so the science and practise remain connected.