How would you expect data from a less populated, rural area to compare to PM2.5 levels in cities like Los Angeles and Pittsburgh? (Hint: Review sources of PM2.5 in the Key Terms tab)

Question

A
PM2.5 levels would be zero

B
PM2.5 levels would be lower but not zero

C
PM2.5 levels would be significantly higher

D
PM2.5 levels would be in between those of Pittsburgh and Los Angeles

Answer 1

The most likely expectation would be:

B - PM2.5 levels would be lower but not zero.

In less populated, rural areas, sources of PM2.5 emissions (such as vehicle traffic, industrial activity, and construction) are typically reduced compared to urban environments like Los Angeles and Pittsburgh, where these activities are more prevalent. However, PM2.5 can still originate from natural sources (like wildfires, dust, and agricultural activities) and long-range transport from urban areas, which means that levels would be lower but not completely absent.