Sea ice breakup in winter

Sea ice & icebergs

Nuclear icebreaker "Taymyr" operating in sea ice North of Dickson, Taymyr, Russia

Sea ice can be an effective insulator between colder winter air and the warmer ocean below, thereby reducing the potential dissipation of heat into space.

There have been occasional undeveloped references to the idea to break up sea ice in winter with ice breakers to increase the amount of outgoing radiation (see for example: McCracken 2009; and https://groups.google.com/g/geoengineering/c/XMR75eB77c8/m/aJrf6Zp3okcJ). Apart from such isolated references, Hunt et al. (2020) provide some back-of-the-envelope calculations on the potential radiative effects of sea ice breakup, and suggest several methods by which to do this. Many of the authors’ ideas about Arctic sea ice removal are reminiscent of earlier plans by Russian and Soviet scientists and engineers to melt the Arctic in order to “ameliorate” the northern climates. Hunt et al. (2020) even directly cite some of these earlier ideas to legitimize their plan. They ultimately consider the following options: (1) Pumping freshwater down to make it less likely for ice to form, (2) Reducing the melting of the Greenland ice sheet thereby limiting freshwater inflow, and (3) Deviating the rivers in the Northern Regions to reduce freshwater inflow into the Arctic.

Technological Readiness Level (TRL)

Low 1

Apart from the highly questionable assumption that it would be beneficial to get rid of Arctic ice, and setting aside the question whether this would require enormous engineering projects in face of already rapidly declining ice levels, the plans suggested by Hunt et al. (2020) belong to the realm of speculative mega-engineering projects that are nowhere close to being operationalised.

Technological Readiness Level (TRL)

A technology with a TRL of 1-3: TRL 1 – Basic; TRL 2 – Concept formulated; TRL 3 – Experimental proof of concept

Scalability

Low 1

Scalability

Physically unable to scale; sub-linear/logarithmic efficiency of scalability

Timeliness for near-future effects

Low 1

Many of these engineering projects would take very long to develop and produce, if they are at all feasible.

Timeliness for near-future effects

Implemented too late to make a significant difference

Northern + Arctic potential

High 3

Although there are no clear technological pathways to do so, and it is highly questionable if it would be desirable to remove Arctic sea ice, this measure would clearly have a huge impact on the Arctic. Apart from the removal of the ice itself, the increased release of heat from the Arctic ocean would likely warm surrounding air temperatures and have a significant warming effect on the Arctic.

Northern + Arctic potential

Very detectable impacts in the Arctic, above the global average; technology ideally/preferably located here

Global potential

Unknown 0

Hunt et al. (2020) do not attempt to provide any definitive calculations on this. Removing sea ice in winter could increase outgoing radiation, but it is unsure how much this would be. The resulting lack of sea ice in spring would undoubtedly lower the earth’s albedo and thereby increase ocean energy absorption.

Cost - benefit

High 1

Hunt et al. (2020) admit that the costs for such projects would be prohibitively high.

Cost - benefit

Cost of investment comparable to cost of avoided damage

Environmental risks

High 1

Apart from side effects of the chosen method to remove the ice, the destruction of Arctic ice would severely endangered local ecosystems, and the warming in the Arctic as a result of increased outgoing radiation would likely equally be disastrous for the region.

Environmental risks

Major, serious risks with a high disaster potential; multiple and cascading risks

Community impacts

Negative 1

Hunt et al. (2020) seemingly uncritically copy the ideas of Soviet scientists about the amelioration of the North and assume that a warming Arctic would be desirable. But the destruction of Arctic ice and further warming of the region would be disastrous for already severely endangered local livelihoods.

Community impacts

Serious detrimental effects

Ease of reversibility

Hard 1

Many of the suggested means through which the ice would be removed would be near-permanent constructions, and there are many doubts if Arctic winter sea ice could regrow if removed (see for example the discussion of Arctic winter sea ice as a tipping point in Armstrong McKay, 2022).

Ease of reversibility

Impossible or very difficult to reverse

Risk of termination shock

Low 3

Risk of termination shock

Low or insignificant termination shock or damage

Legality/governance

Medium 2

Given the huge objections against it, it is highly unlikely that the removal of Arctic sea ice and the technologies required to do so could become part of international legal and governance structures. The sea ice within the Exclusive Economic Zone of individual countries may however be modified under domestic laws, e.g., by the river freshwater outflows.

Legality/governance

Fits within existing structures to a certain degree, but some policy changes are needed to deploy at scale

Scientific/media attention

Low 1

Apart from Hunt et al. (2020), there have been several independent references to the breaking up of sea ice in winter. However, this remains a very niche idea that is not given much credible attention.

Scientific/media attention

Very low attention from individuals and/or abandoned ideas; low media attention; no commercial interest.

References

Armstrong McKay, D. I., Staal, A., Abrams, J. F., Winkelmann, R., Sakschewski, B., Loriani, S., ... & Lenton, T. M. (2022). Exceeding 1.5 C global warming could trigger multiple climate tipping points. Science, 377(6611), eabn7950. https://doi.org/10.1126/science.abn795

Hunt, J. D., Nascimento, A., Diuana, F. A., de Assis Brasil Weber, N., Castro, G. M., Chaves, A. C., ... & Schneider, P. S. (2020). Cooling down the world oceans and the earth by enhancing the North Atlantic Ocean current. SN Applied Sciences, 2(1), 1-15. https://doi.org/10.1007/s42452-019-1755-y.

MacCracken, M.C. (2009). On the possible use of geoengineering to moderate specific climate change impacts. Environmental Research Letters, 4(4): 045107. https://doi.org/10.1088/1748-9326/4/4/045107

Related ideas

Oceans & marine

Enhancing oceanic light availability below the photic layer

Ocean bioproductivity through photosynthesis stops beyond the photic layer as no more energy from the sun can penetrate beyond that point.

Atmosphere / solar radiation

Space-based solar radiation management

GHG emissions reductions and future negative emissions are the only sustainable solutions to stabilize or even reverse global warming as they counter the cause of the problem. However, such actions will likely take a while to materialize, and inertia in the climate system and “baked-in” warming already ensures major changes in global temperatures and the nearing of several tipping points. Solar radiation management (SRM) techniques seek to reduce global temperatures by reflecting incoming solar radiation. They would thereby not fix the underlying issue of the warming effects of GHGs, but are according to the United Nations Environment Programme (UNEP) Review on Solar Radiation Modification Research (2023) ‘the only known approach that could be used to cool the Earth within a few years’.

Shelf-Iceberg, North of Antarctic Peninsula

Ice sheets and glaciers

Ice sheet stabilization via buttressing

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 lockedin warming (State of the Cryosphere report 2022).

Blueberries (Vaccinium myrtillus) as part of the vegetation 5 years after forest fire, Mykland, Aust Agder, Norway

Land-based measures

Rewilding

Large areas of the Northern and Arctic regions consist of permafrost, almost permanently frozen soil. As global temperatures rise, these permafrost areas are thawing at an ever faster rate. This thawing leads to massive amounts of GHGs being released into the atmosphere, either as CO2 or CH4 in generally dry or wet areas. Because methane is a very potent GHG, the thawing of the permafrost is considered a major tipping point in the climatic system. Permafrost preservation is of the utmost importance because Arctic terrestrial regions alone hold up to 1500 Pg C (Schuur et al. 2015), and although there is large uncertainty about the total amount of emissions from permafrost (Miner et al. 2022), especially when it comes to nonlinear abrupt thawing (Turetsky et al. 2020), significant amounts of carbon release is to be expected as the Northern regions warm.

Old whale bone providing fertile conditions for vascular plants, Antarctic Peninsula

Industry

Biochar

The concentration of GHGs in the atmosphere will have to be stabilized or lowered to mitigate or even reverse current global warming. To achieve this, current GHG emissions need to be reduced. Such mitigation strategies will however take time to deploy, and some emission sources will be difficult to mitigate. Moreover, since current atmospheric levels are already having a major warming effect, negative emission or Carbon Dioxide Removal (CDR) measures that reduce the amount of GHGs in the atmosphere are an active topic of research.

Melting glacier ice, Alpefjord, Northeast Greenland National Park

Ice sheets and glaciers

Artificial glaciers

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.

Sea ice covered Coast in July, Sterlegova, Taymyr, Russia

Sea ice & icebergs

Sea ice thickening

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.

High waves at Tromøy shore, "Rollingstone" (Raet) National Park in planning, Arendal

Oceans & marine

Hydrological system modification - Ocean current modification

Hydrological systems play an important role in energy distribution in the climate system. For the Arctic and Northern region the clearest example of this is the habitability of the European Arctic thanks to the Gulf Stream. Furthermore, there are several access points to the Arctic ocean that play an important role in shaping local geophysical conditions.