Beijing and other Chinese cities arechoking under a blanket of smog. It’s so thick in Tianjin that planes can’t land. Authorities have issued the first “red alert” of 2016, and 1,200 Beijing-area factories were ordered to shut down or to reduce production, according press reports.
This winter, officials will be equipped with forecasting tools from IBM and Microsoft that they tested last year. IBM’s tool, used by the city government, is designed to incorporate data from traditional sources, such as the 35 official multipollutant air-quality monitoring stations in Beijing, and lower-cost but more widespread sources, such as environmental monitoring stations, traffic systems, weather satellites, topographic maps, economic data, and even social media. Microsoft’s system incorporates data from over 3,000 stations around the country. Both IBM’s and Microsoft’s tools blend traditional physical models of atmospheric chemistry with data-hungry statistical tools such as machine learning to try to make better forecasts in less time.
“Our advantage or differentiation is to combine all those together,” says environmental engineer Jin Huang, who is project manager for the Green Horizon Initiative at IBM Research–China, in Beijing. IBM reports an accuracy of over 80 percent for 3-day forecasts and around 75 percent for its 7- to 10-day forecasts. Microsoft now provides China’s Ministry of Environmental Protection with a 48-hour forecast that as of 2015 reached 75 percent accuracy for 6 hours and 60 percent for 12 hours in Beijing.
How best to combine physics models and machine learning for air-quality forecasts is “an active research area,” says atmosphere scientist Vincent-Henri Peuch, the head of the European Copernicus Atmosphere Monitoring Service in Reading, England. He adds that blending is the right choice: Both types of models have something to offer and do not need to preclude each other. The market seems to agree so far. IBM now offers its combined model in New Delhi and Johannesburg, and the Beijing startup AirVisual also offers machine-learning-enhanced forecasts for private commercial use.
Beijing officials have been able to claim some success beating down their fine-particle pollution levels: They reported that 2015 levels were 6 percent below 2014 levels.