Rajesh Kumar is Deputy Director of the Research Applications Laboratory of the National Center for Atmospheric Research (NCAR), Boulder, Colorado, USA. His research focuses on air quality that is one of the most important socioeconomic and environmental concern around the world today. Air pollution is responsible for about 7 million premature deaths every year and loss of about 80-120 million ton of food. He synergistically integrates ground- and satellite-based air quality monitoring with atmospheric composition and modeling capabilities to address a number of air quality issues including transport and transformation of air pollution, the relative importance of local and foreign emissions, deterministic and probabilistic air quality predictions, aerosol-climate interactions, heterogeneous atmospheric chemistry, chemistry-climate interactions, projection of future air quality, and impact of air quality for public health and food security.