The effects of mean sea level rise and strengthened winds on extreme sea levels in the Baltic Sea. Issue 6 (December 2018)

• Record Type: Journal Article
• Authors: Hieronymus, Magnus; Dieterich, Christian; Andersson, Helén; Hordoir, Robinson
• Is Part Of: Theoretical & applied mechanics letters. Volume 8:Issue 6(2018)
• Page Start: 366
• Page End: 371
• Publication Date: 2018-12
• Subjects: Extreme sea levels -- Sea level rise -- Wind speeds -- Baltic Sea; Mechanics, Applied -- Periodicals; Mechanics, Analytic -- Periodicals; Mechanics, Analytic; Mechanics, Applied; Periodicals; 620.1
• DOI: 10.1016/j.taml.2018.06.008
• Languages: English
• ISSNs: 2095-0349

Abstract

HIGHLIGHTS: The sensitivity of extreme sea levels to winds and sea level rise is investigated. Simple extreme sea level parametrization is developed. Sea level extremes increase more with increasing winds where they are already high. ABSTRACT: Mean sea level rise and climatological wind speed changes occur as part of the ongoing climate change and future projections of both variables are still highly uncertain. Here the Baltic Sea's response in extreme sea levels to perturbations in mean sea level and wind speeds is investigated in a series of simulations with a newly developed storm surge model based on the nucleus for European modeling of the ocean (NEMO)-Nordic. A simple linear model with only two tunable parameters is found to capture the changes in the return levels extremely well. The response to mean sea level rise is linear and nearly spatially uniform, meaning that a mean sea level rise of 1 m increases the return levels by a equal amount everywhere. The response to wind speed perturbations is more complicated and return levels are found to increase more where they are already high. This behaviour is alarming as it suggests that already flooding prone regions like the Gulf of Finland will be disproportionally adversely affected in a future windier climate.