Tropical Wave

A tropical wave also called an easterly wave or tropical easterly wave is an atmospheric area in and around the Atlantic Ocean. It is an elongated atmospheric area of low air pressure.

Key Points for UPSC Prelims

• The relatively low air pressure area is oriented north to south and it moves from east to west across the tropic regions to cause cloudiness and thunderstorms.
• Tropical waves are generally carried westward by the prevailing easterly winds along the tropical and sub-tropical regions near the equator.
• They can lead to the formation of tropical cyclones in the north Atlantic and north-eastern Pacific regions.
• Tropical waves are the origin of around 85% of intense Atlantic hurricanes and around 60% of Atlantic tropical cyclones.
• Near India, the Easterly waves move fast across the Bay of Bengal and usually target Tamil Nadu and Kerala, as well as Sri Lanka.

Tropical wave may bring rain to South Peninsula

A greater geographical area can be impacted by the rain-laden tropical wave with the wet spell getting extended over the larger South Peninsula.

As per the India Meteorological Department (IMD) heavy rainfall is likely over Puducherry, Tamil Nadu, and Karaikal.

In addition to this, as per the Sri Lanka Meteorological Department, isolated rain showers are expected over Coastal Andhra Pradesh, South Interior Karnataka, Yanam, and Rayalseema. Sri Lanka to the South can also see heavy weather as is usual with tropical waves.

India Meteorological Department (IMD)

It is the main agency responsible for weather forecasting, meteorological observations, and seismology in India. The agency is under the Ministry of Earth Sciences, Government of India. It is also the Regional Specialised Meteorological Centres of the World Meteorological Organisation (WMO).

WMO has 6 Regional Specialised Meteorological Centres.

World Meteorological Organisation (WMO)

It is a UN Specialized agency that is responsible for strengthening international cooperation on hydrology, atmospheric science, geophysics and climatology. It was formed in the year 1950 and is headquartered in Geneva, Switzerland.