A new study supported in part by CPO’s Atmospheric Chemistry, Carbon Cycle and Climate (AC4) Program provides an overview of the Alaskan Layered Pollution And Chemical Analysis (ALPACA) field experiment. ALPACA is funded largely by the National Science Foundation (NSF) and is aimed at understanding winter air pollution in cold regions like Fairbanks, Alaska, where residents often worry about air quality. AC4-supported scientists Becky Alexander (University of Washington) and Lu Hu (University of Montana) worked with a large international team of researchers to describe ALPACA’s findings on pollution sources, chemical processes, and how weather affects pollution. This study is crucial because it sheds light on how winter conditions impact air quality and helps communities like Fairbanks tackle pollution issues. AC4 funded these two researchers to investigate changes in chemistry, carbon, and composition in urban atmospheres in the context of a changing climate.
The ALPACA project grew from community concerns and survey results that illustrated public opinions on addressing air quality issues. The collaborative effort to collect measurements on pollution included intercepting pollutant plumes from power plants with balloons, remote sensing with lidar, capturing air chemistry data with instruments fixed to buildings, directly sampling snow, and more. The results, published in ACS ES&T Air, found that outdoor air had high levels of particles and gases, especially during pollution events when stable weather trapped pollution close to the ground. Indoors, cooking and pellet stoves could lead to higher particle levels than outside. The study showed how temperature inversions in cold regions trap pollution close to the ground, affecting air quality. Overall, ALPACA is the first large-scale international experiment focusing on high-latitude city pollution, providing valuable insights into winter air quality, which is crucial for addressing pollution in similar Arctic urban areas facing increasing human activity and urbanization.
For more information, contact Clara Deck.
Image credit: University of Alaska, Fairbanks
