Arctic Ice Preservation
The Arctic is warming 2x faster than the rest of the planet, causing the loss of 75% of the polar continent’s ice volume and 50% of ice surface area over the past three decades. Since the Industrial Revolution around 1750, average temperatures in the North Pole have risen as much as 5.5˚ Fahrenheit. As the air and waters of the Arctic grow warmer, sea ice melts further towards the pole each year, multiyear ice disintegrates and long-lived glaciers calve off into the sea.
Sea ice plays a critical role in determining the stability of the Arctic. Forming at the edges of the Arctic ocean in mid-Autumn, Arctic sea ice grows to cover millions of square miles over the winter, until the melting season begins in March. Because it covers an extensive surface area and has a white surface color, sea ice reflects enough sunlight to have a cooling effect on both the Arctic and to a lesser degree, the Earth itself.
Albedo is a measure of how reflective a surface is, according to the amount of light bounces off versus the amount that gets absorbed. After sea ice melts, it does reform in the winter. However, this young and thin sea ice has an albedo value only 30%, and is susceptible to annual melting in the summer months.
Until recently, thick older ice with an albedo value of 75% persisted through the year, helping to keep the ocean, the Arctic and the planet as a whole cooler. In the last four decades, however, 95% of this highly reflective ice has disintegrated.
As sea ice melt increases due to warming, a feedback loop ensues, accelerating the melt rate and regional temperature increase in the Arctic: when sea ice melts, the Arctic loses its highly reflective surface cover, exposing the open ocean to the sun, whose dark blue color absorbs up to 95% of incoming light.
The result is a net warming effect on both sea water and the ambient air, since less light is now being reflected away. This additional warming causes more sea ice to melt, leading to further solar gain from the exposed ocean surface, creating an accelerating, self perpetuating feedback loop.
This feedback loop, compounded by the ongoing warming effect of continued CO2 emissions, is tipping the Arctic towards severe decline within decades. Currently it is projected that the Arctic ocean will be entirely free of sea ice by 2035.
And what happens in the Arctic doesn’t stay there. Ice melt contributes to rising sea levels that threaten to inundate hundreds of millions of people living in coastal cities and towns across the planet over the next century.
Elsewhere, the loss of arctic sea ice has been implicated in the erratic jet stream over North America in recent years, causing polar vortexes to plunge as far south as Texas and disrupting regular precipitation patterns in California, contributing to drought and worsening wildfires there. As the Center for Science Education writes:
“Typically, a large difference in temperature between the air of the polar vortex and the air in the mid-latitudes drives the polar jet stream. However, the Arctic is warming faster than other areas of the planet, which makes the difference in temperature less distinct. This causes the polar jet stream to meander north and south instead of making a beeline around the planet”
Erratic Polar Jet Stream Causes Extreme Weather and Drought in the U.S. Credit: National Weather Service
Additionally, the Arctic reflects a significant amount of sunlight off the Earth’s surface, but as its ice melts, the reflective value (also known as albedo, a measure of how reflective a surface is by how much light bounces off versus gets absorbed) is being reduced, leading to a warming effect equivalent to 25% of humanity’s CO2 emissions over the past 30 years.
As global greenhouse gas reduction targets have come and gone without sufficient action by the nations of the world, various groups have begun to consider direct, emergency interventions to preserve the ice at the top of the world, such as:
Building concrete walls around glaciers to protect from warming seawater,
Millions of wind-powered pumps to recirculate cold water up from the depths
Covering glaciers with huge blankets during the summer months
While these ideas are both expensive and technically difficult given the harsh environment of the poles, one simple idea shows promise: enhancing the albedo of sea ice by applying a top layer of benign, natural materials. The Arctic Ice Project (AIP), founded by Dr. Leslie Field, has spent nearly a decade researching, developing and testing this idea, and have settled on white, silica microspheres as the optimum material (silica comprises most beach sand and is used to make glass).
AIP has identified a suitable candidate in the K1 microsphere created by the 3M corporation. The K1 silica bead is ideal for its bright hue, low cost, nontoxic ingredients and particle size, which is tiny yet still large enough to prevent internal harm from animals that might ingest it. The K1 spheres also float, and wouldn’t absorb oil in the case of a nearby spill.
Dr. Field and her team propose layering K1 over young ice as it develops, to protect vulnerable ice during the summer melt season and support young ice’s growth over winter into thick, multiyear sheets. Whereas young ice typically only reflects 30% of sunlight, AIP claims that K1 would boost albedo by 15%.
Ice911 refers to the application of Arctic Ice Project’s K1 microspheres. Credit: Arctic Ice Project
AIP aims to apply K1 in strategic and targeted fashion, rather than broadly across the continent, focusing on covering 15,000 - 100,000 square kilometers in the Fram Straight and Beaufort Gyre. In these areas, bolstering young ice will stem further warming and aid the growth of ice further to the north in central Arctic.
In modeling scenarios AIP ran in collaboration with Climformatics, this narrow approach yielded benefits for the whole Arctic:
Cooling the Arctic by about 1.5˚ C
Increasing ice thickness 20 - 50 centimeters
Growing ice concentration 15 - 20% across the continent
Stabilizing sea ice volume, instead of an 8% decline per decade
Stemming the feedback loop of sea ice loss and ocean warming
For the rest of the planet, fortifying the Arctic could help stabilize the polar jet stream, slow sea level rise and provide a cooling effect of 1.02˚ C globally. It’s possible this approach could be utilized in the Antarctic and Greenland as well, preserve sea ice, slow sea level rise and further cool the planet.
In terms of operations, AIP foresees large crude carrier ships receiving K1 spheres via rail and setting sail for the Arctic in October and November. During this period, ice is in the “grease”phase of its development, the prime time to ensure the silica is deposited near the top layer of ice. The carrier ship would use large blowers to deposit its load of K1, which AIP estimates could be accomplished within a day.
The scale of K1 application envisioned by AIP would require 300,000 tons of silica, which is more than 2x that of current global production, but not unreasonable to achieve. This much silica would cost $300 million, and overall project costs would range between $1 - $5 billion annually.
For potentially stabilizing the Arctic, slowing down sea level rise, preventing polar vortexes and cooling the globe, this price is modest to say the least. Thus, using silica for targeted albedo enhancement of sea ice looks like one of the most promising ways to preserve the Arctic. It would be relatively cheap, scalable and reasonable to achieve both technologically and operationally.
The key hurdle to clear is environmental safety, since it is an open question whether, or to what extent, thousands of tons of silica spheres could harm Arctic wildlife and ecosystems. One concern, raised by Cecilia Bitz, an atmospheric scientist at the University of Washington, is that K1 spheres would clog the Arctic environment. K1 could block sunlight from reaching marine plankton, and its not definitive that internal digestion by animals wouldn’t be a problem.
While AIP has found in lab tests that no harm was done to birds and fish fed K1 spheres, the team plans to conduct more rigorous tests on ecotoxicology and the effects on phytoplankton.
The beads would eventually break down in the ocean, which naturally has huge amounts of silica, but in response to environmental safety concerns Dr. Field suggested in a BBC article that she’s considering “whether to tweak their composition such that they dissolve after a period of time”. Fortunately, AIP doesn’t intend to cover the entire Arctic in silica beads, but rather just a few locations representing at most 0.6% the area of the whole continent, so any impacts would be limited.
As with many climate solutions that can scale to meet the challenge, such as large solar or wind farms, we must clearly weigh the benefits of potentially stabilizing the Arctic as a whole against some local impacts that may occur. The greater good of climate benefits shouldn’t by default overrule legitimate local impacts, but we must keep in mind the bigger picture.
Consider: how does concern over the potential impact from clogging in less than 1% of the Arctic compare to the impact on all polar species of ice free summers, which will eliminate habitat for many polar mammals and birds, and usher in new global shipping routes with associated air pollution and open untapped oil reserves for drilling?
Sea ice albedo enhancement may come with some impacts, but appears to offer a viable, cost-effective path to preserving the Arctic, slowing sea level rise, reducing weather extremes in North America and providing a modest global cooling effect.