NASA Science Facilities on the International Space Station

The International Space Station offers a unique vantage point for observing the Earth's ecosystems with hands-on and automated equipment. These options enable astronauts to observe and explain what they witness in real time. Station crews can observe and collect camera images of events as they unfold and may also provide input to ground personnel programming the station's automated Earth-sensing systems. This flexibility is an advantage over sensors on unmanned spacecraft, especially when unexpected natural events such as volcanic eruptions and earthquakes occur.
A wide variety of Earth-observation payloads can be attached to the exposed facilities on the station's exterior; already, several instruments have been proposed by researchers from the partner countries. The station contributes to humanity by collecting data on the global climate, environmental change and natural hazards using its unique complement of crew-operated and automated Earth-observation payloads.

See www.nasa.gov/mission_pages/station/research