This past week the San Francisco Bay Area has declared three consecutive "Spare the Air" alerts, showing that even with a harsh winter just behind us, things are already heating up for the west coast of the United States.

In the wake of a prolonged stretch of high temperatures and low winds, the Air Quality Management Districts for Sacramento and the Bay Area have both declared "Spare the Air" alerts for their regions, warning people who go outside that the air may be unhealthy for sensitive groups.

The "Spare the Air" air quality alert was initially established by the Bay Area Air Quality Management District in 1991 as a way to warn residents when air quality became unhealthy due to a combination of weather factors and weakening ozone, according to the official "Spare the Air" website. The alerts, which also serve as a way to protect the ozone from greenhouse gasses, were quickly adapted by regions also suffering from heavy smog conditions.

The San Fransisco Bay Area, known as the Bay Area for short, encompasses metropolitan areas around San Francisco, Oakland, San Jose, and several small counties. Because the region is commonly exposed to intense heat waves with little wind exposure, air quality can be dangerously low. Car exhaust, for instance, won't rise as quickly in heightened temperatures. Without wind to sweep these stagnant clouds of smog away, the sea-level region often finds itself stuck breathing its own filth, prompting health warnings.

On "Spare the Air" days, officials ask that citizens take extra measure to avoid creating air pollution, such as carpooling or limiting their driving.

Wednesday's air alert was the third consecutive alert for the Bay Area this week, reminding residents why steps must be taken to reduce smog in the region. During the summer months each year, the Bay Area declares a single season-long "Spare the Air Alert" as intense heat and stagnant air become commonplace.

Currently, the Bay Area and Sacramento are only reporting moderate air quality warnings. You can track air quality alerts for the entire country via the National Weather Service's Air Quality Forecast Guidance map.