Even if the world were to stop emitting greenhouse gases tomorrow, sea levels would continue to rise. Sea level rise is not only absolutely guaranteed, but the process will continue for hundreds or even thousands of years, experts claim.
Rising water levels are one of the most serious consequences of global warming, which are already being felt. Since 1880, the average global sea level has already risen by 16-21 cm. Half of this rise has occurred in the last thirty years.
(...)
The best and worst-case scenarios up to 2100
How bad could it get? It is difficult to predict precisely, but the IPCC (Intergovernmental Panel on Climate Change) has attempted to model various scenarios based on how successfully humanity manages to mitigate the climate crisis. Each potential scenario is the result of complex calculations (shared socio-economic pathways or SSPs, which are expressed numerically) that take into account potential emissions, as well as potential socio-economic changes such as population size, urban density, education, land use, and prosperity, all of which influence the use of fossil fuels.
The most optimistic forecast: 1.5 °C warming = 28-55 cm sea level rise.
If the world moves towards a more sustainable future, meets development goals, and achieves the Paris climate target—to keep global warming to 1.5 °C by 2050—the average global sea level is expected to rise by 0.28-0.55 m in the near future, i.e., in the next century. The IPCC calls this the sustainability scenario (SSP rating 1-1.9).
Intermediate scenario: 1.8 °C = 32-62 cm
Assuming that socio-economic and technological trends do not change significantly, inequality will persist, but we will manage to reach the low-emission target (SSP 1-2.6), which will keep global warming within 1.8 °C by the end of the century; sea levels are forecast to rise by 0.32-0.62 m.
Regional rivalry: 2.7 °C = 44-76 cm
A medium greenhouse gas emission scenario (SSP 2-4.5) where net-zero is not reached by 2100. This scenario envisages resurgent nationalism, which makes environmental issues a low international priority as countries strive for development rather than sustainability.
Inequality: 3.6 °C = 55-90 cm
A very high emission scenario in which CO₂ levels double by 2100 compared to current levels (SSP3-7), due to highly unequal investments in human capital, increasing inequality between and within countries, and increased investment in coal mining.
Fossil-fuel-driven development: 4.4 °C = 63-101 cm+
Social and economic development is linked to the use of fossil fuel resources to support energy-intensive lifestyles worldwide. The IPCC also warns of a low-probability, high-impact scenario (SSP5-8.5), according to which sea level rise could exceed 2 metres by the end of this century due to ice sheet instability.
Read the full article