Drops and bubbles in the environment

Bubbles and drops are ubiquitous in nature and play critical roles in many important environmental processes. Most familiar is the life-sustaining role of rain. Less familiar are their roles in the thermal budget of the atmosphere and their role in pathogen dispersal. In this paper, we highlight new  applications where drops and bubbles have important impacts on the environment and health arenas. The paper highlights the physical processes that enable the creation of drops and bubbles and the new challenges that they raise. Among them, we discuss, in particular, the role of drops and bubbles in the dispersal of life and biological organisms and the role of drops and bubbles in pathogen dispersal, disease transmission  and health hazards.