Air Pollution Could Actually Save Arctic Sea Ice. But Should We Use It?

Some types of pollution, it turns out, could actually save some of the sea ice that other types of pollution are melting.

Oct 24 2015, 8:30pm

Photo: Alan Baekken/Flickr

The Earth doesn't always behave exactly as you'd expect it to.

For one bizarre example, take this: pollution in the form of greenhouse gases like carbon dioxide and methane is causing the atmosphere to warm at alarming rates and melting Arctic ice. At the same time, some pollutants can actually reflect the sun's rays into space, helping the planet cool down and—wouldn't you know it—helping preserve sea ice. So, what's an Earth-bound population to do?

A new study released this week sought to answer that very question. The paper shows that it's likely that aerosols, or tiny particles that reflect light, like soot, have mitigated about 60 percent of the warming in the Arctic over the 20th century. Published by Geophysical Research Letters, the paper also notes that air pollution could actually buy Arctic sea ice another decade. Right now, the Arctic is expected to have an ice-free summer in 2057. But if we were to revert to air pollution levels of the year 2000, the scientists say, the first ice-free summer would come as early as 2045.

A NASA data visualization gives a glimpse at the startling loss of sea ice over the past few decades.

So some types of pollution, it turns out, could actually save some of the sea ice that other types of pollution are melting.

Climate deniers have jumped on similar research into this phenomenon in the past. Earlier this month, Benny Peiser, director of the Global Warming Policy Foundation, a climate sceptic lobby group, told Breitbart that a similar study was "evidence…that climate models…should never have been trusted in the first place."

However, climate scientists say this doesn't change the big picture.

"The base driver of sea ice melt ultimately is anthropogenic greenhouse gases," Walt Meier, an Arctic expert at NASA, told Climate Central. "That ultimately causes enough warming to lose sea ice in summer in the Arctic. Aerosols are a secondary effect so they can reinforce carbon dioxide-influenced warming or slow it down."

There are ways that scientists have tried to alter the Earth's atmosphere to help mitigate climate change before. Called climate geoengineering, the schemes are meant to cool the Earth, but often come with high stakes. The study is also in no way an argument for a geoengineering scheme that puts more air pollution into the air, its authors say.

For one thing, aerosol particles are generally terrible for human health. In the U.S. alone, clean air legislation that limits the amount of aerosol particulates in the air is expected to prevent more than 230,000 early deaths and provide $2 trillion in economic benefits by 2020, according to the Environmental Protection Agency.

Another problem with aerosols is that they can worsen the effects of other pollutants, as well as increase floods and droughts by changing the way clouds form.

In the end, the scientists say, there's really only one solution: reduce the amount of carbon emissions in the atmosphere. But that, unlike polluting, is not an easy thing to do.