Combat relative sea-level rise at global scale- Presenting the International Panel on Land Subsidence (IPLS)

Accelerated relative sea-level rise (SLR) rate is driven by by changing climate and land elevation decline at the world's coastlines. Today, many coastal environments and communities, such as river deltas, wetlands, and cities experience accelerated land subsidence rates due to human-induced processes such as groundwater extraction. Coastal populations are preferentially located in low-lying and subsiding regions, >500M people worldwide living at the coast experience, on average, a four times higher relative sea-level rate than the global mean average (Nicholls et al., 2021).

Although subsidence is the dominant force driving relative SLR worldwide, its effect is often overlooked and/or not fully integrated into global and local sea-level rise projections. As a result, SLR impact assessments underlying coastal adaptation plans for many governments around the world underestimate future relative SLR rates and consequent flood risks. It is more important than ever for the global scientific community that studies land subsidence, its drivers and impacts from all biophysical and socio-economical domains to unite, in a similar fashion as the IPCC has come into existence in the 80's, to combat the growing global challenge of land subsidence.

We propose the International Panel on Land Subsidence (IPLS). In a similar spirit to the IPCC, we envision the IPLS to grow in the coming years and become a global focal point of scientific knowledge made available in an accessible matter, to place subsidence higher on the international agenda, and communicate effective strategies for mitigation and adaptation of coastal subsidence to governments.

We present a roadmap to grow the IPLS initiative by developing a global community of forward-looking scientists. IPLS aims to communicate ongoing developments, organize knowledge exchange and brainstorming events, training workshops, and write joint scientific papers on crucial issues. IPLS's first milestone is to present the First Global Assessment Report on Land Subsidence, including 21st-century projections of land elevation, to inform governments, scientific communities and the public worldwide.

The IPLS welcomes experts from all related disciplines to join the initiative and become part of this global community.