Pumping water onto ice sheets

Although the model studies of Frieler et al. (2016) and Feldmann et al. (2019) show that such a measure might be effective in stabilizing ice sheets or reducing sea level rise, the technology would be prohibitively expensive and complicated to install and maintain due to extreme weather conditions and the remote nature of these ice sheets. Although similar kinds of pumps exist, there have been no further engineering studies into how they might be adjusted and adapted to these conditions as they would require far too much energy to be feasible. The Feldmann et al. (2019) model study shows that lifting the water 640 m on average to cover an area ‘similar to the size of the state of Costa Rica or half the size of Iceland' would already require a significant amount of currently used global energy, and that this would roughly double if the water had to be desalinated first. One option could be to build 12,000 wind turbines, similar to those described in ambitious macro-engineering projects to generate energy on a large scale in Antarctica (Bolonkin and Brook, 2008). But given the difficulties in constructing and maintaining them, this seems to make this project very unattractive compared to other schemes.

Snow accumulation is a low sensitivity knob in the climate system, and melt rates are often far greater than disposition rates. Even if successful in increasing glacier mass, this could eventually accelerate the ice sheet melt and thereby negate any positive effects this measure would have had.

Apart from these geophysical objections, the costs and investments are likely too high for this idea to be scalable.

Constructing the required infrastructure would be a major undertaking, while continuously rising global temperatures would require ever-greater volumes of water to be pumped onto the ice sheets.

This measure seems “plausible” only in Antarctica where lower surface temperatures prevent much surface melt. It would likely be futile in Greenland where surface melt is already extensive. However, if effective in Antarctica, it would also reduce sea level rise in the Northern and Arctic regions.

Although water deposition on top of ice sheets could reduce sea level rise (Frieler et al., 2016), ice sheet dynamics would evolve as a result of it, and it is doubtful it would have a significant global effect in the long run (Moore et al., 2020).

Frieler et al. (2016) state that the ‘costs cannot be reliably estimated,’ but would be extremely high. Moore et al. (2020) therefore conclude it is an ‘entirely implausible use of resources.’

Feldmann et al. (2019) state that '[t]he building of the wind turbines and the further infrastructure, as well as the extraction of the ocean water itself, would mean the loss of a unique natural reserve, with serious effects on its sensitive marine and coastal ecosystems'.

Feldmann et al. (2019) warn that it would be very hard to deal with potential negative effects and hazards of such an enterprise. Any accumulated snow will stay until melted away (potentially over thousands of years).

The Protocol on Environmental Protection to the Antarctic Treaty (Secretariat of the Antarctic Treaty, 1991) means to protect the Antarctic, and would most certainly be a major obstacle for the deployment of such measures on the continent. In the Arctic, such an intervention on the Greenland ice sheet would likely have to deal primarily with Greenlandic national governance systems (Corbett and Parson, 2022).