Tar sandstone from the Monterey Formation of Miocene age; southern California, USA. Photo © Wikimedia contributor James St. John

Obviously we never thought that extracting oil from tar sands was ecologically friendly, but a new study published in Nature has found that, in Canada (but presumably everywhere else too), the process releases much more fine particle air pollution than previously believed. Bobby Magill reports for Scientific American:

In one of the first studies of its kind, scientists have found that tar sands production in Canada is one of North America’s largest sources of secondary organic aerosols—air pollutants that affect the climate, cloud formation and public health.

The study, published Wednesday in the journal Nature, showed that the production of tar sands and other heavy oil—thick, highly viscous crude oil that is difficult to produce—are a major source of aerosols, a component of fine particle air pollution, which can affect regional weather patterns and increase the risk of lung and heart disease.

Aerosols from the production of heavy oil is a growing climate and pollution concern because new tar sands developments are on the drawing board in Venezuela, Utah and elsewhere, the study says. Today, heavy oil accounts for 10 percent of global crude oil production worldwide, mostly in Canada, which produced about 1.1 billion barrels of oil in 2014.

“The results indicate that the environmental impacts of Canadian tar sands are much larger than previously recognized,” said Allen Robinson, a mechanical engineering professor at Carnegie Mellon University who is unaffiliated with the study. “What is so novel about this paper is that tar sands were not on anybody’s radar as a major source of aerosol.”

Using aircraft to measure air pollution over the Alberta tar sands region, the researchers found that tar sands production emitted between 55 and 101 metric tonnes of secondary organic aerosols per day. That’s comparable to aerosol pollution measured downwind of major cities such as Mexico City and Paris and greater than the pollution measured near Tokyo and the Northeast U.S.

Aerosols in urban air pollution and from major industries such as the Canadian tar sands are of concern to scientists because they can affect regional climate patterns and have helped to warm the Arctic.

In a separate study published Wednesday, researchers at the RIKEN Advanced Institute for Computational Science in Japan, said aerosols in the Arctic have a “profound” impact on the global climate system. Climate models often underestimate the extent to which aerosols from industrial air pollution—especially those containing black carbon—warm the atmosphere because they assume Arctic air is cleaner than it actually is, the study said.

Black carbon contained within some aerosols can be deposited on Arctic ice sheets and mountain snowpack. The black carbon spread across the ice darkens its color, absorbing more heat and causing the ice to melt more quickly. Less ice and snow on the earth’s surface reduces the earth’s ability to reflect sunlight, increasing surface temperatures.

Read the rest of the original article here.