If you’ve noticed the large green laser that shoots 25 kilometres skyward just north of Nesters, don’t worry, Whistler is not being invaded by aliens. The beam is part of a light detection and radar station (LIDAR), which is designed to provide information about Whistler’s air quality.

Located at the Environment Canada weather station near Nesters Market, the LIDAR station is just one of six in Canada and part of the Canadian Operational Research Aerosol LIDAR Network (CORALNet). The green laser measures aerosols, which are tiny particles suspended in the air. Some occur naturally from volcanoes, dust storms, forest and grassland fires, living vegetation and sea spray, while others result from human activities, such as burning fossil fuels and altering natural surface cover.

Did you know that Whistler’s LIDAR station can detect ash from a fire in Ontario? This fun fact helps scientists understand the roles of manmade, locally produced air pollutants as well as those that move into the area via meteorological “highways” and their impacts on air quality. Every 10 seconds the LIDAR station provides vertical aerosol profiles from near ground to 25 km into the sky. It operates 24 hours a day, seven days a week except when it’s raining or aircraft fly over the site. The system is operated remotely and the data, which are updated every hour, are publicly available on www.coralnet.ca.

The LIDAR station is important to Whistler because it helps us understand what influences aerosol concentrations in Whistler’s atmosphere, whether they are human-made, locally produced air pollutants or those which move in to the area via metrological highways. Readings from the machine help us better understand how aerosols impact Whistler’s air quality, which allows us to make better decisions in order to protect our quality of life.

What’s the big deal about aerosols, anyway? Well, aerosols are important to understand for a number of reasons. Polluting aerosols destroy ozone molecules, which deplete the ozone layer that protects us from the harmful effects of the UV rays. Aerosols also affect the Earth’s climate by interacting with the sun and Earth’s radiation, by modifying clouds, and by decreasing visibility.

Whistler’s LIDAR station is connected to a network called CORALNet, which is composed of six LIDAR stations located at sites across Canada. The sites were chosen to cover the entire country and to maximize the ability to monitor both long-range transport events as well as regional air quality issues. The sites from west to east are Whistler, University of British Columbia, Bratt’s Lake, Sask., Centre For Atmospheric Research Experiments (Egbert, Ont.), University of Sherbrooke (Que.) and Acadia University (Wolfville, N.S.).

While the big green laser continues to collect aerosol data at Nesters, long-term monitoring of traditional air pollutants such as particulate and ground-level ozone is still taking place at Meadow Park. Real-time results for the Meadow Park station are available at www.bcairquality.ca and comparisons to health reference levels are tracked at www.whistler2020.ca.

Draft data for 2009 has just been released and based on local air monitoring of regional contaminants, Whistler’s air quality is quite good. This indicator measures the number of days that the provincial Air Quality Index (AQI) for Whistler is below “good.” The index is primarily driven by ground-level ozone, a regional air pollutant that is created by a reaction of other air pollutants and oxygen in the presence of sunlight.

In 2009, however, air quality was less than “good” for 412 hours throughout the year, up from 139 hours in 2008. Contributing factors for 2009 could be the number and volume of regional forest fires, including two that burned on Blackcomb Mountain.

The Whistler Way 2010 Commuter Challenge,Sept. 22 to Oct. 5, is a two-week fun competition among participating businesses to reduce single-passenger vehicle trips and encourage people to switch from driving alone and use preferred modes: walk, cycle, skateboard etc. Registration begins Sept. 13 at thewhistlerway.ca. To get involved, contact: Donna Savage, RMOW Commuter Challenge Coordinator, at dsavage@whistler.ca.

Want to learn more about The Whistler Way 2010 Commuter Challenge? Check out thewhistlerway.ca