Reducing Uncertainty in 21st Century Sea-Level Predictions and Beyond

Abstract

Sea-level rise is one of the most critical issues the world faces under global warming. Around 680 million people (10% of the world’s population) live in low-lying coastal regions that are susceptible to flooding through storm surges and from sea-water infiltration of fresh groundwater reserves, degradation of farmland and accelerated coastal erosion, among other impacts. Rising sea level will exacerbate these problems and lead to societal impacts ranging from crop and water-supply failures to breakdowns of city infrastructures. In time, it is likely such changes will necessitate the migration of people with substantial economic cost and social upheaval. Here, we discuss the physical processes influencing 21st Century sea-level rise, the importance of not using 2100 alone as a benchmark, the changes that are already locked in, especially after 2100, and those that can be avoided. We also consider the need for both adaptation and mitigation measures and early warning systems in this challenging global problem. Finally, we discuss how the scientific prediction of sea level rise can improved through international coordination, cooperation and cost sharing.

Future of Freshwater Ecosystems in a 1.5°C Warmer World

“…However, even modest sea level rise can substantially alter the character of low lying coastal freshwater ecosystems, rapidly shifting them into more brackish or saline systems unable to support their characteristic freshwater biodiversity (Grieger et al, 2020). As Siegert and Pearson (2021) note, under high emissions scenarios, we cannot rule out 2 m of sea level rise by 2100, and up to 5 m by 2150.…”

The Zero Emissions Commitment and climate stabilization

“…As the cryosphere is also slow to adjust, the total global mean sea level rise is expected to be closer to 0.6 m/°C of surface warming after 100 years, or 4 m/°C after 2000 years and 7 m/°C after 10,000 years. During the last interglacial period, for example, temperatures were 0.5°C to 1.5°C warmer, and the sea level was 5-10 m higher (11,59).…”

Algorithm Applied to SDG13: A Case Study of Ibero-American Countries

“…Approximately 10% of the world's population lives in low-lying coastal regions that may be affected by sea level rise [9], leading to infiltration of seawater into fresh groundwater reserves, degradation of croplands, and accelerated coastal erosion [9]. Research also reveals an increase in concerns about severe heat waves [10], forest fires [11], heavy rains [12], and droughts [13], leading to an increase in casualties [14] and social tensions [15].…”