What are air pollutants? Where do they come from? Why are they important? Check out these fact sheets and videos to learn the answers to these questions and more.
Metro Vancouver measures air quality in the Lower Fraser Valley with scientific instruments at air quality stations close to where people live, work and play. We determine how clean the air is by comparing these measurements to the Air Quality Health Index and ambient air quality objectives
Ozone is a pungent gas made of three oxygen atoms. Ozone can form in two places: 1) high up in the atmosphere, and 2) right down at the ground. When it’s up high in the ozone layer it’s “good” ozone. The ozone layer acts like sunscreen lotion for the Earth – blocking out most of the Sun’s harmful ultraviolet rays.
Nitric oxide (NO) and nitrogen dioxide (NO2) are known collectively as nitrogen oxides (NOx). On hot and sunny days, nitrogen oxides can react with other pollutants to form ground-level ozone. Nitrogen oxides can also react with other pollutants to form fine particulate matter.
Particulate matter (PM) is made up of tiny solid or liquid particles that float in the air. Particulate matter can be emitted directly and it can be formed indirectly when nitrogen oxides or sulphur oxides react with ammonia in the atmosphere.
Sulphur dioxide is a colourless gas that smells like burnt matches. It is emitted when fossil fuels containing sulphur are burned. Sulphur dioxide can also react with other substances in the air to form particulate matter which can affect human health and create a “white haze” in the air.
Air Quality Part 1
Smog Formation in the Lower Fraser Valley
Watch more videos - Air Quality Part 2, 3, and 4
What are greenhouse gases? Where do they come from? Why are they important? Check out these fact sheets and videos to learn the answers to these questions and more.
What is the greenhouse effect? Carbon dioxide, methane, nitrous oxide and water vapour are “greenhouse gases” (GHGs). What does that mean? They allow solar radiation to pass through the atmosphere, but prevent heat from escaping into space. Human activities like the burning of fossil fuels are enhancing the greenhouse effect, increasing average global temperatures, and changing climate systems.
Did you know that carbon dioxide isn’t the only gas that can influence the Earth’s climate? Three common air pollutants - black carbon (soot), ground-level ozone (smog) and methane - can also have a negative climate impact. We call these three substances ‘short-lived climate forcers’. Read more to find out why.
Introduction to Climate Change
Preparing for Climate Change
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Metro Vancouver acknowledges that the region’s residents live, work, and learn on the shared territories of many Indigenous Peoples, including 10 local First Nations: q̓ic̓əy̓ (Katzie), q̓ʷɑ:n̓ƛ̓ən̓ (Kwantlen), kʷikʷəƛ̓əm (Kwikwetlem), máthxwi (Matsqui), xʷməθkʷəy̓əm (Musqueam), qiqéyt (Qayqayt), Semiahmoo, Sḵwx̱wú7mesh Úxwumixw (Squamish), scəw̓aθən məsteyəxʷ (Tsawwassen), and səlilwətaɬ (Tsleil-Waututh).
Metro Vancouver respects the diverse and distinct histories, languages, and cultures of First Nations, Métis, and Inuit, which collectively enrich our lives and the region.
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