Glacier albedo increase

Ice sheets and glaciers

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). The surface of many mountain glaciers has moreover significantly darkened due to a general increase in atmospheric black carbon and other kinds of aerosols.

It has recently been suggested that hollow glass microspheres (HGM, see also see sea ice albedo increase) could be used to increase the albedo of mountain glaciers and thereby slow their melt. The non-profit organization Bright Ice Initiative (https://brighticeinitiative.org/) is currently exploring this idea in collaboration with several other US and Indian organizations like the Healthy Climate Initiative (https://healthyclimateinitiative.org/) and Climformatics (https://climformatics.com/).

Technological Readiness Level (TRL)

Medium 2

This measure faces similar issues as sea ice albedo enhancement does: the material already exists, but there remain large uncertainties around effectiveness, material behavior, and environmental issues. While the application of HGM on sea ice has been the subject of several studies, there has been no peer reviewed publications of its usage on high mountain glaciers yet. In collaboration with scientists from IIT Indore a field experiment is scheduled to start on the Chhota Shigri Glacier in North India in the summer of 2023 (Project Himalayas Brochure, 2023).

Technological Readiness Level (TRL)

A technology with a TRL of 4-6: TRL 4 – validated in lab; TRL 5 – validated in relevant environment; TRL 6 – demonstrated in relevant environment

Scalability

Low 1

This measure would only serve to reduce the melting of specific glaciers on land, and is likely most effective on relatively flat surface areas (Project Himalayas Brochure, 2023). If HGM is found to work, there could be possible scaling advantages in the production process that reduce costs.

Scalability

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

Timeliness for near-future effects

Medium 2

The suggested material already exists, but there is no certainty if this measure would actually work.

Timeliness for near-future effects

Implemented in time to make some difference, although questionable

Northern + Arctic potential

Low 1

Apart from the issues that also face the application of HGM on sea ice, the vast expanse of the Arctic and Northern regions would likely make widespread operationalization difficult.

Northern + Arctic potential

No noticeable extra positive effect beyond the global average; technology is unsuited to the Arctic

Global potential

Low 1

It would mainly concern targeted interventions with limited global effects.

Global potential

Insignificant to be detected at a global scale

Cost - benefit

High 1

There are no current estimates of the price of deployment, although the figures for the application of HGM on sea ice indicate high costs. To this, it must be added that the proposed surface area to be treated is far smaller than what Arctic Ice Project envisions for the Arctic sea ice, and that the potential sites of distribution would be many smaller surfaces instead of a single large area, which probably would come with increased costs.

Cost - benefit

Cost of investment comparable to cost of avoided damage

Environmental risks

Medium 2

There have been no studies on environmental risks. In a recent unpublished manuscript on the behavior of various HGM’s in the Arctic, Farkas et al (2023) found that some variants in their experiment leached in seawater overtime. Since mountain glaciers are generally of great importance to ecosystems and human drinking water (Cauvy-Fraunié and Dangles, 2019), this would be an essential element to investigate further.

Environmental risks

More widespread and possibly regional impacts that extend beyond the immediate solution deployment location

Community impacts

Unknown 0

Some of the sites on which this technique would be deployed might be of particular importance to local communities. For instance because of religious or financial reasons, or, especially in the context of Asian high mountain ranges, because it is a source of drinking water. The protection of such a glacier could therefore be important to such a community. However, it has to be made sure that the HGMs are environmentally safe and do not pose a risk to human health.

Ease of reversibility

Easy 3

This measure would likely stop when the HGM are washed away or buried, although they would potentially need to be cleaned up if suddenly found undesirable.

Ease of reversibility

Easily reversible naturally

Risk of termination shock

Low 3

Risk of termination shock

Low or insignificant termination shock or damage

Legality/governance

Medium 2

Legality/governance

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

Scientific/media attention

Medium 2

The promoters of this idea have been quite vocal, and even organized an online benefit concert to raise awareness and gain sponsors for their idea. So far the idea seems not to have been picked up in scientific circles. A recent article in The New Yorker likely provided it great public exposure (Riederer, 2023).

Scientific/media attention

Some attention within the scientific community, including published research and funding programmes; some media attention; some commercial interest

References

Cauvy-Fraunié, S., & Dangles, O. (2019). A global synthesis of biodiversity responses to glacier retreat. Nature Ecology & Evolution, 3(12), 1675-1685. https://doi.org/10.1038/s41559-019-1042-8

Farkas, J., Molid, M., Hansen, B. H., Nordam, T., Nordtug, T., & Throne-Holst, M. Characterization of Hollow Glass Microspheres with Potential for Regional Climate Intervention to Preserve Arctic Sea Ice. Available at SSRN 4377493. https://doi.org/10.1016/j.coldregions.2023.103967

Project Himalayas. 2023. Saving the Himalayan glaciers: a field trial to slow the melting of glacial ice. Brochure.

Riederer, Rachel (April 25, 2023). A Heat Shield for the Most Important Ice on Earth. The New Yorker. https://www.newyorker.com/news/the-control-of-nature/a-heat-shield-for-the-most-important-ice-on-earth

Related ideas

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.

Autumn at Mykland after forest fire 5 years ago

Land-based measures

Wildfire management

Fire is important to the healthy functioning of boreal ecosystems. However, as wildfires increase, they release greater amounts of GHGs into the atmosphere, contributing to climate change. While boreal fires typically contribute 10% of global CO2 emissions, in 2021, an extreme fire year, they accounted for 23% of global emissions (Zheng et al. 2023). Particulate matter in wildfire smoke (soot or black carbon, see also Black carbon mitigation) can also reduce albedo on sea ice and glaciers, enhancing ice melt (e.g., Aubry-Wake et al. 2022). Wildfires are projected to increase in both frequency and intensity over the coming decades (UNEP 2022). By 2050, wildfires in North American boreal forests alone could contribute close to 12 Gt CO2, almost 3% of the remaining global CO2 emissions to keep temperatures to below 1.5oC (Phillips et al. 2022a).

Mountain pine and spruce forest in winter, Hillestadheia, Norway

Atmosphere / solar radiation

Snowfall enhancement

With the exception of some regions like Antarctica, global snowfall amount and frequency have decreased, and the timespan during which snow cover remains has shortened (Zender 2012). This has multiple effects on human and natural systems as it influences widely diverging processes such as reducing surface albedo and changes in the hydrological cycle.

Industry

Radiative covering and building technologies/ Passive daytime radiative cooling

An increase in GHGs in the atmosphere leads to a greater amount of outgoing infrared radiation from the earth being retained. There are several ideas to reduce the resulting warming by modifying surface radiation processes.

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’.

Industry

Enhanced weathering (on land)

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.

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.

Ice sheets and glaciers

Increasing humidity around glaciers and ice sheets

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).