Abstract
The rising costs of climate change merit serious evaluation of potential climate restoration solutions. The highest rate of change in climate is observed in the Arctic where the summer ice is diminishing at an accelerated rate. The loss of Arctic sea ice increases radiative forcing and contributes to global warming. Restoring reflectivity of Arctic ice could be a powerful lever to help in the effort to limit global warming to 1.5°C. Polar ice restoration should be considered in planning of 1.5°C pathways. In this paper, a novel localized surface albedo modification technique is presented that shows promise as a method to increase multiyear ice using reflective floating materials, chosen so as to have low subsidiary environmental impact. Detailed climate modeling studying the climate impact of such a method reveals more than 1.5°C cooler temperatures over a large part of the Arctic when simulating global sea ice albedo modification. In a region north of Barents and Kara Seas temperatures have been reduced by 3°C and in North Canada by almost 1°C. Additionally, there are notable increases in sea ice thickness (20–50 cm Arctic wide) and ice concentration (>15–20% across large parts of central Arctic). These results suggest that the geoengineering technology proposed in this study may be a viable instrument for restoring Arctic ice.
Plain Language Summary
This paper describes a method to preserve and restore ice in the Arctic in order to reduce the effects of climate change. This method is benign by design, developed to restore ice in the Arctic in targeted areas to build back the reflective ice that has melted over the past several decades. The aim is to restore the Arctic ice's historic function of reflecting sunlight. By applying reflective materials such as glass microspheres on young, low‐reflectivity sea ice, we can protect the young ice from the summer Sun, much like a white shirt fends off the Sun for a person on a hot summer day. This way the ice may be conserved and converted over time into highly reflective multiyear sea ice. Climate modeling shows that this method can cool the Arctic significantly and can rebuild Arctic ice area and volume, hence reducing Arctic as well as global temperature rise.
Key Points
Arctic ice regrowth is an effective lever on global climate
Albedo modification of sea ice is an effective method of ice preservation
Albedo enhancements increase the sea ice area and volume and decrease the surface temperature