Increasing humidity around glaciers and ice sheets

One of the potentially most catastrophic effects of contemporary global warming would be the dramatic increase in sea levels as a result of the melting Greenland and Antarctic ice sheets. Even if all current emissions were immediately stopped, sea level rise could still occur because of locked-in warming (State of the Cryosphere report 2022).

Terrestrial carbon can be stored in biomass above or below the ground, and in soils themselves. Soil organic matter can form differently, and have different amounts of plant and microbial components depending on the availability of water (Cotrufo and Lavallee, 2022). The large amounts of the Earth that have been brought under cultivation over the past 12.000 years have significantly degraded soil carbon levels, and have released some 110 billion metric tons of carbon (Sanderman et al. 2017). Soil security and health is increasingly being recognised as essential for planetary health (Kopittke et al. (2022).

Up to 50% of the world’s glaciers are predicted to disappear this century, with many more at risk if emission reduction targets are not met (Rounce et al. 2023). Furthermore, the melting of mountain glaciers impacts the rates and seasonality of meltwater abundance and scarcity.

Arctic sea ice extent has rapidly decreased over the last few decades, with most multi-year ice disappearing altogether. This has already had major effects on local communities and ecosystems. The disappearance of the relatively reflective sea ice also leads to a dramatic decrease of albedo in the Arctic and subsequent high energy uptakes by the darker water during the Arctic summers.

Surface albedo has a significant impact on global climate (Zhang et al. 2022). Plants play an important role in this. Matthews et al. (2003), for example, estimate that the spread of agriculture has led to a global cooling of around 0.17°C, as agricultural crops tend to have a higher albedo than wild vegetation (Monteith and Unsworth 1990).

The deep waters in the Baltic are severely deoxygenated. Although the causes of the current state are complex, this is mainly a result of increased eutrophication from sewage and agricultural runoff from surrounding lands, which leads to extreme bioproductivity (Rolff et al. 2022). Some species manage to survive in the upper water layers, but many organisms living on the seafloor are severely impacted by the hypoxia, thereby influencing the health of a wide network of ecosystems and biochemical processes. There are attempts to reduce nutrient runoff into the Baltic (see for example: https://helcom.fi/baltic-sea-action-plan/). However, some argue these will be insufficient and argue for engineering solutions to the issue.

Up to 50% of the world’s glaciers are set to disappear this century, with many more at risk if emission reduction targets are not met (Rounce et al. 2023).

Oceans play an important role in global heat transfer and carbon storage processes. As global temperatures and atmospheric carbon levels rise, some have suggested artificially modifying the vertical movement of water to enhance these processes.