The Union Ministry of Earth Sciences has announced it will set up a cyclone warning center in Kerala and boost weather forecasting in the state with another Doppler radar.
The new center will be set up in Thiruvananthapuram. At present, India Meteorological Centre (IMD) has six cyclone warning centers, four along the east coast at Chennai, Visakhapatnam, Bhubaneswar and Kolkata, and two along the west coast at Ahmedabad and Mumbai.
According to officials, the center will be equipped with state-of-the-art forecasting tools to provide daily weather alerts and coastal warnings. It is expected to be functional within a month.
The ministry has also proposed setting up another C-band Doppler weather radar at Mangalore to provide “nowcast” alerts for severe weather, including thunderstorms triggered by heavy rain for the next 2-3 hours.
The radar, which costs Rs 3 crore, will cover northern Kerala and Karnataka and is expected to be installed by the end of next year.
Currently, there are two Doppler radars in the state, at Kochi and Thiruvananthapuram, which cover the central and southern districts, respectively. With the addition of another radar, the entire state will be covered for monitoring rainfall and severe weather events.
IMD has developed many new models and tools right from nowcasts (2-3 hours) to extended range forecasts (15-20 days’ lead time).
Doppler Effect refers to the change in wave frequency during the relative motion between a wave source and its observer. It was discovered by Christian Johann Doppler who described it as the process of increase or decrease of starlight that depends on the relative movement of the star.
Doppler Effect works on both light and sound objects. For instance, when a sound object moves towards you, the frequency of the sound waves increases, leading to a higher pitch. Conversely, if it moves away from you, the frequency of the sound waves decreases and the pitch comes down. The drop in pitch of ambulance sirens as they pass by and the shift in red light are common examples of the Doppler Effect.
The use of Doppler Effect in astronomy in relation to light waves depends on the fact that the spectra of stars are not constant. Different stars exhibit different absorption lines at defined frequencies, but Doppler Effect is identifiable only when these absorption lines are away from these defined frequencies.
There are various applications of Doppler Effect. It is used in:
- Medical imaging and blood flow management
- Flow management
- Velocity profile management
- Satellite communication
- Vibration measurement