1. Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado
2. National Oceanic and Atmospheric Administration/Earth System Research Laboratory, Boulder, Colorado
3. Institute of Environmental Assessment and Water Research, Barcelona, Spain
4. Instituto Interuniversitario de Investagación del Sistema Terra en Andalucía, Centro Andaluz de Medio Ambiente (CEAMA), University of Granada, Granada, Spain
5. Department of Civil and Environmental Engineering, Duke University, Durham, North Carolina
6. Department of Atmospheric Science, University of Utah, Salt Lake City, Utah, and Storm Peak Laboratory, Desert Research Institute, Steamboat Springs, Colorado
7. MTA-PE Air Chemistry Research Group, University of Pannonia, Veszprém, Hungary
8. Basic Environmental Observatory Moussala, Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria
9. CSIRO Oceans and Atmosphere, Aspendale, Victoria, Australia
10. Environmental Meteorology Research Division, National Institute of Meteorological Sciences, Seogwipo-si, Jeju-do, South Korea
11. School of Earth and Environmental Sciences, Seoul National University, Seoul, South Korea
12. Environment and Climate Change Canada, Toronto, Ontario, Canada
13. Climate Environmental Research Monitoring, South African Weather Service, Stellenbosch, South Africa
14. Department of Atmospheric Sciences, National Central University, Taoyuan, Taiwan
15. Department of Environmental Sciences, University of Puerto Rico, Río Piedras Campus, San Juan, Puerto Rico
16. Storm Peak Laboratory, Desert Research Institute, Steamboat Springs, Colorado
17. Department of Physics and Astronomy, Appalachian State University, Boone, North Carolina
18. El Arenosillo Atmospheric Sounding Station, Atmospheric Research and Instrumentation Branch, National Institute for Aerospace Technology, Huelva, Spain
19. State Key Laboratory of Severe Weather, and Key Laboratory of Atmospheric Chemistry, Chinese Academy of Meteorological Sciences, China Meteorological Administration, Beijing, China