Small remote-sensing satellites can be used for environmental monitoring. One application is in monitoring forest cover.1 Detecting flooding is another application where small satellites can perform.2 Project Persephone's support of warning systems for communities threatened by landslides in equatorial alpine regions could also be helpful in environmental monitoring.
1 "Eyes in the sky spy on threatened jungles"?, Reuters. "Nigel Sizer, director of [World Resources Institute]'s Forests Initiative [....] said within five years, micro satellites with 5 to 10 meters resolution will deliver real-time imaging to rapidly detect any changes in forest cover. In a decade, high-resolution video would likely be available." ⇑
2 See e.g., "NovaSAR – A Novel, Low Cost, Medium Resolution Spaceborne SAR System Development", Phillip Whittaker et al. ⇑