Extreme sea levels at different global warming levels

Abstract

The Paris agreement focused global climate mitigation policy on limiting global warming to 1.5 or 2 °C above pre-industrial levels. Consequently, projections of hazards and risk are increasingly framed in terms of global warming levels rather than emission scenarios. Here, we use a multimethod approach to describe changes in extreme sea levels driven by changes in mean sea level associated with a wide range of global warming levels, from 1.5 to 5 °C, and for a large number of locations, providing uniform coverage over most of the world’s coastlines. We estimate that by 2100 ~50% of the 7,000+ locations considered will experience the present-day 100-yr extreme-sea-level event at least once a year, even under 1.5 °C of warming, and often well before the end of the century. The tropics appear more sensitive than the Northern high latitudes, where some locations do not see this frequency change even for the highest global warming levels.

Multisector Dynamics: Advancing the Science of Complex Adaptive Human‐Earth Systems

“…Applying exploratory modeling in MSD research represents a challenge as well as an opportunity to transform how human-Earth systems modeling is currently done. Innovative approaches to experimental design can (a) improve the representation of the deep uncertainties affecting a system (for example due to internal variability as well as uncertainties surrounding model structures and inputs), (b) help to sample potential futures, and (c) shed light on the impacts of uncertainties on consequential MSD outcomes (e.g., Lehner et al, 2020;Tebaldi et al, 2021). Applying scenario discovery methods on the generated output space can identify critical combinations of uncertain factors, consequential human actions, or tipping points that drive poor outcomes (e.g., Dolan et al, 2021;Hadjimichael et al, 2020;Lamontagne et al, 2018Lamontagne et al, , 2019.…”

Remote Sensing of the Coastline Variation of the Guangdong–Hongkong–Macao Greater Bay Area in the Past Four Decades

“…The development of coastlines brings great economic benefits but may also shine a light on environmental pollution and ecological problems [77]. Coastline changes may be related to global warming, rising sea levels and tropical cyclone activities [78]. In order to ease the conflict between human and nature, China promulgated Notice of the State Council on Several Issues Concerning Further Strengthening the Work of Marine Management (http: //www.gov.cn/, accessed on 12 August 2020) and Regulations of Guangdong Province on the Administration of the Use of Sea Areas (http://www.gd.gov.cn/, accessed on 15 August 2020) to strictly approve marine development activities and control land reclamation and the mining of sea sand.…”

Popular extreme sea level metrics can better communicate impacts

“…Climate and sea level scientists have developed various metrics and indicators to describe changes in the frequency of contemporary ESLs under various climate change scenarios (Hunter 2012;Buchanan et al 2017;Rasmussen et al 2018;Frederikse et al 2020;Vitousek et al 2017;Taherkhani et al 2020;Church et al 2013;Howard and Palmer 2020;Feng et al 2018;Fox-Kemper et al 2021;Tebaldi et al 2021). For example, ESL amplification factors (AFs; also called "factors of increase" or "multiplication factors") denote the change in the expected frequency of a given contemporary ESL under a given climate change scenario.…”