Giving Compass' Take:

• Research from the McKelvey School of Engineering at Washington University in St. Louis revealed that it is difficult to adequately measure pollution in cities, and more data is necessary to make accurate calculations.

• How can donors help support this research? How would this data help inform city leaders about their surrounding environment? Could better pollution data spur environmental action?

•  Read about the effects of traffic pollution on children.

“I often see rankings of the most polluted city in the world,'” says Randall Martin, professor in the energy, environmental, and chemical engineering department in the McKelvey School of Engineering at Washington University in St. Louis.

“These rankings are misleading,” he says, “because there is insufficient information to know.”

In a paper in Atmospheric Environment: X, Martin outlines the extent of the gap between what researchers know and don’t know about on-the-ground levels of fine particulate matter, also known as PM2.5.

Understanding the amount of pollution in the air requires on-the-ground monitoring, but many cities—ostensibly some with high PM2.5 levels—have no monitoring at all. In India, for example, there is just one monitor for every 6.8 million people. Such sparse monitoring fails to represent pollution variability.

Martin and colleagues found that just about 9% of the world’s population lives in areas that have more than three monitors per million people. About 18% of the population live in areas without monitoring.

Beyond mitigating health concerns, a better understanding of pollution on the ground is important for several reasons. For Martin, whose research sits at the intersection of remote sensing and global modeling, having accurate data is the only way to develop accurate models.

“Part of our analysis involves relating what satellites measure to ground-level PM2.5,” he says. “If we relied only on ground-based monitors, we would have insufficient information.”

In order to improve the ground-level data, Martin and colleagues propose a robust “integrated monitoring framework” composed of different types of monitoring equipment focused on the most densely populated areas, or even on those most prone to variability. They calculate that in order to achieve a goal of one monitor per million people, thousands of new monitors will need to come online.

Read the full article about better data on pollution by Brandie Jefferson at Futurity.