Welcome to the KAIR (the Kelly air) group. Population growth and the desire for improved living standards places ever-increasing stress on several interconnected resources: energy, air quality, water, and food. Our group focuses on three aspects of this grand challenge: (1) how low-cost, air-quality sensing can improve our understanding of local-air quality and how it can engage the community, (2) how particle physicochemical properties and their transformations during atmospheric aging affect human health, and (3) how changes in our energy landscape affect air, water and food resources.