How are remote sensing satellites helpful in detecting a natural disaster like Tsunami and earthquake?

Remote sensing satellites orbit the earth at different altitudes. They gather electromagnetic energy reflected or scattered back from a part of the earth's atmosphere below the satellite.

Satellite remote sensing is a powerful tool and can clearly reveal the factors causing environmental degradation occurring in any part of the world.

Monitoring emergencies as they happen, keeping track of a flood, alerting Coast Guard to pollutants in water, detecting burning fires are some of the important tasks done by remote sensing satellites.