Impact of Atlantic Ocean Hurricane Forecasts on India: Climate Stressors and Cyclone Predictions

Impact of Atlantic Ocean Hurricane Forecasts on India: Climate Stressors and Cyclone Predictions

Sub : Geo

Sec :Climatology

Why in News

Countries surrounding the Indian Ocean are increasingly vulnerable to climate change, both in terms of chronic stressors like warming oceans and acute stressors such as cyclones and extreme weather events. The Atlantic hurricane forecasts have prompted a fresh look at the state of India’s own weather prediction capabilities and the potential effects on regional climate dynamics.

Global Climate Stressors Impacting Indian Ocean Region

Chronic Stressors: These include rising sea levels, warming oceans, and increased extreme rainfall events. Chronic stressors occur consistently over time, making the region more susceptible to acute stressors.

Acute Stressors: These are events that exacerbate the impact of chronic conditions, such as cyclones, heavy rainfall, and flash droughts. Acute stressors often cause sudden, severe damage.

Hurricane and Cyclone Forecasts:

Meteorologists had predicted a historic hurricane season for 2024 based on the expected development of La Niña. However, despite early hurricanes like Helene and Milton, the strong La Niña conditions have not materialized as forecasted.

El Niño and La Niña Effects: Historically, El Niño tends to suppress cyclones, while La Niña intensifies them. However, the global warming patterns observed during 2023-2024 have altered this predictable link.

What is Hurricane:

A hurricane is a powerful and destructive tropical storm characterized by strong winds, heavy rainfall, and low atmospheric pressure.

Hurricanes are also known as cyclones or typhoons in different parts of the world.

In the Atlantic Ocean and Northeast Pacific, they are called hurricanes, while in the north western Pacific, they are referred to as typhoons, and in the South Pacific and Indian Ocean, they are known as cyclones.

About EL Nino

El Nino refers to the large-scale ocean-atmosphere climate interaction linked to periodic warming in sea surface temperatures across the central and east-central Equatorial Pacific.

It is associated with high pressure in the western Pacific. El Nino adversely impacts the Indian monsoons and hence, agriculture in India.

El Nino means lesser than average rains for India. Indian agriculture is heavily dependent on the monsoons and because of this, lesser rainfall during the monsoons generally translates to below-average crop yields.

What happens because of El Nino?

The cool surface water off the Peruvian coast goes warm because of El Nino. When the water is warm, the normal trade winds get lost or reverse their direction.

Hence, the flow of moisture-laden winds is directed towards the coast of Peru from the western Pacific (the region near northern Australia and South East Asia).

This causes heavy rains in Peru during the El Nino years robbing the Indian subcontinent of its normal monsoon rains. The larger the temperature and pressure difference, the larger the rainfall shortage in India.

About La Nina:

It means the large-scale cooling of ocean surface temperatures in the central and eastern equatorial Pacific Ocean, together with changes in the tropical atmospheric circulation, namely winds, pressure and rainfall.

It has the opposite impacts on weather and climate as El Niño, which is the warm phase of the El Niño Southern Oscillation (ENSO).

Weather Changes due to La Nina:

The Horn of Africa and central Asia will see below average rainfall due to La Niña.

East Africa is forecast to see drier-than-usual conditions, which together with the existing impacts of the desert locust invasion, may add to regional food insecurity.

It could also lead to increased rainfall in southern Africa.

It could also affect the South West Indian Ocean Tropical Cyclone season, reducing the intensity.

Southeast Asia, some Pacific Islands and the northern region of South America are expected to receive above-average rainfall.

In India, La Niña means the country will receive more rainfall than normal, leading to floods.

Cyclone Activity in the North Indian Ocean

The North Indian Ocean, particularly the Arabian Sea, has witnessed an increasing number of cyclones. While the region has been relatively quiet in recent years, this unpredictability only highlights the difficulty in forecasting future cyclone patterns.

Rapid Intensification: Cyclones gain energy from the upper ocean layers, and as these waters warm, cyclones may intensify rapidly, with wind speeds increasing by over 55 km/h in less than 24 hours.

India’s Progress in Cyclone Forecasting and Disaster Management

Improved Forecasting Systems: India has made significant strides in improving its cyclone forecasting capabilities, with advanced early warning systems that have helped reduce loss of lives.

Geographical Advantages: The areas over the Arabian Sea and Bay of Bengal where cyclones typically intensify are relatively small, limiting their size and strength. Additionally, many cyclones are steered away from India’s mainland, reducing their potential impact.

About Tropical Cyclone:

A tropical cyclone is an intense circular storm that originates over warm tropical oceans and is characterized by low atmospheric pressure, high winds, and heavy rain.

A characteristic feature of tropical cyclones is the eye, a central region of clear skies, warm temperatures, and low atmospheric pressure.

Storms of this type are called hurricanes in the North Atlantic and eastern Pacific and typhoons in South-East Asia and China. They are called tropical cyclones in the southwest Pacific and Indian Ocean region and Willy-willies in north-western

Storms rotate counter-clockwise in the northern hemisphere and clockwise in the southern

The conditions favourable for the formation and intensification of tropical storms are:

• Large sea surface with temperature higher than 27° C.
• Presence of the Coriolis force.
• Small variations in the vertical wind speed.
• A pre-existing weak low-pressure area or low-level-cyclonic circulation.
• Upper divergence above the sea level system.