 Climate change is happening at a dangerous pace. Most of the CO2 emissions that are responsible for climate change occur in cities. Transportation, cars, trucks, airplanes, home heating, air conditioning, industry. If we're going to reduce the pace of climate change, cities have to do their part all over the world. We've built Beacon, the Berkeley Environment Air Quality and CO2 Network to provide cities with observations that allow them to know they're doing their part. In the next five years, all cities on the planet need to take quick and deliberate action. We stand ready with Beacon to provide observations that help them know that their plans are occurring on track and on target.