PM2.5 refers to atmospheric particulate matter (PM) that have a diameter of less than 2.5 micrometers. PM2.5 levels have been increasing from 2000 in China (red line). A decrease jump can be found after the 2008 Beijing Olympics due to the environmental protection policies. However, a very obvious increasing trend can be found both before and after the 2008 Beijing Olympics.

PM2.5 data over China aquired from 2008-2010, based on data from the Multi-angle Imaging Spectroradiometer (MISR) instrument on the Terra satellite, the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on the Terra and Aqua satellites, and a chemical transport model called GEOS-Chem.

https://earthobservatory.nasa.gov

Equipment and measurements taking place of emission factors in East China

The image on the left is satellite image taken on 1st October of an agricultural area in East China. On the right is the same area 6 days later taken with a drone, showing burnt areas. Red circles are the locations of a new small fire detection algorithm (5th Oct 2015), proving that real fires are being detected.