Regional mean sea level projections for Denmark

The scripts to produce sea level time series in Klimaatlas v2022a.

Purpose

To produce the sea level time series for Danish Klimaatlas sea level index calculation. The sea level time series processed from IPCC AR6. The electronic data of SLR are through the NASA/IPCC Sea Level Projections Tool (https://sealevel.nasa.gov/ipcc-ar6-sea-level-projection-tool). The sea level projections in AR6 are produced by a package named the Frameworks for Assessing Changes To Sea-level (FACTS). The original data includes the median value (50%) and the likely range (upper 83% and lower 17%) and very likely range (upper 95% and lower 5% limits).

Scenarios

The SSPs are now included into the latest cycle of climate modeling, known as the Coupled Model Intercomparison Project version 6 (CMIP6), for the IPCC AR6. Five scenarios will be used for standard runs in CMIP6 for a worldwide agreement, with the designation of individual scenarios consisting of the name of the fundamental pathway followed by two numbers indicating the extra radiative forcing attained by 2100. SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5 are their designations.

The low-confidence and high-impact scenario

There is a small but significant risk of rapid sea level rise outside the likely estimates, which is mirrored in relatively high numbers for the upper percentiles for global-sea level because of uncertainty of ice-sheet-processes. IPCC AR6 now divides uncertainty into two types, normal uncertainty and deep uncertainty. Likely range projections do not include those ice-sheet-related processes whose quantification is highly uncertain or that are characterized by deep uncertainty. For evaluating this uncertainty, IPCC employ both a poll of experts and a smaller, more specific organized expert opinion. AR6 now incorporates this sort of expert opinion to evaluate risks that cannot be properly modelled but yet cannot be disregarded.crucial to comprehend what the risks are. Klimaatlas will provide a guideline for those who are intereted in this low-confidence scenario.