Gist of Increasing incidence of severe cyclones | Gist of Rajya Sabha TV / RSTV (now Sansad TV) - UPSC PDF Download

RSTV: The Big Picture- Increasing Incidence Of Severe Cyclones

Introduction:

The powerful Cyclone Tauktae battered the western coast. The cyclone is classified as an ‘Extremely Severe Cyclonic Storm’ and is the fifth-strongest cyclone ever in recorded history in the Arabian Sea. At a time,when India is battling a massive spread of Covid-19, the cyclonic storm has unleashed a double-edged sword to people in the western coastal areas. The IMD categorises tropical storms, which rotate in an anti-clockwise direction, into Depression, Deep Depression, Cyclonic Storm, Severe Cyclonic Storm, Very Severe Cyclonic Storm, Extremely Severe Cyclonic Storm, and Super Cyclonic Storm. Cyclones occur in the pre-monsoon months of May-June and the post-monsoon months of October-November. India has faced 170 storms since 1970, which is the fourth highest after the United States, the Philippines and China in the same duration.
A cyclone is a large scale air mass that rotates around a strong center of low atmospheric pressure. Cyclones are characterized by inward spiraling winds that rotate about a zone of low pressure. Tropical cyclones are intense low-pressure areas confined to the area lying between 30° N and 30° S latitudes, in the atmosphere around which high velocity winds blow. Horizontally, it extends up to 500-1,000 km and vertically from surface to 12-14 km.
The unusually high number of cyclones in the Arabian Sea, some of them extremely severe with wind speeds higher than 167 kmph, are a result of warming seas and changes in sea surface temperature distribution, says Hiroyuki Murakami, a climate scientist at the US National Oceanic and Atmospheric Administration’ Geophysical Fluid Dynamics Laboratory.

Reasons for increasing cyclones:

• The first factor is the rising sea surface temperature.
• This warm ocean contributed to intensifying cyclones, leading to more severe storms.
• The second factor is that onset of winter monsoon is delaying, leading to a longer storm season.
• The last factor is increases in anthropogenic aerosols, leading to changes in sea surface temperature distribution that in turn change monsoon circulation, resulting in more active storms.

Impact of Climate change and increasing cyclones:

• The studies associated with temperature suggest that the Indian Ocean is warming, particularly the Arabian Sea, which is doing so at the fastest rate.
• Previously, tropical cyclones in the Arabian Sea were restricted to Gujarat.
• In the past decade though, Maharashtra, Goa, Kerala and Karnataka have also become more vulnerable to cyclones. A recent example is “Nisarga”.
• The Arabian Sea is quickly responding to climate change signals, heating rapidly and driving more and more cyclones, and excessive rainfall.
• In general, when global warming proceeds, the surface ocean gets warmer. This warm condition is favourable for intensification of tropical cyclones.
• But increasing greenhouse gasses also cause warming in the upper atmosphere, that makes the atmosphere more stable.
• This stable atmosphere is unfavourable for tropical cyclones. Therefore, the frequency of tropical cyclone genesis would decrease when global warming proceeds.
• But once a storm generates, the storm can develop into an intense storm due to the warmed surface ocean.
• Regional tropical cyclones are much more complex. Some regions get more active storms by changing circulation whereas some regions get less active. Expecting changes in regional tropical cyclones contain a lot of uncertainty.

Negative effects of Cyclones on India:

• India is highly vulnerable to natural disasters especially cyclones, earthquakes, floods, landslides, and drought. Natural disasters cause a loss of 2% of GDP every year in India. According to the Home ministry, 8% of total area in India is prone to cyclones.
• Strong Winds/Squall: Cyclones are known to cause severe damage to infrastructure through high speed winds. Very strong winds which accompany a cyclonic storm damages installations, dwellings, communications systems, trees etc., resulting in loss of life and property. Gusts are short but rapid bursts in wind speed are the main cause for damage. Squalls on the other hand, are longer periods of increased wind speed and are generally associated with the bands of thunderstorms that make up the spiral bands around the cyclone.
• Torrential rains and inland flooding: Torrential rainfall (more than 30 cm/hour) associated with cyclones is another major cause of damages. Unabated rain gives rise to unprecedented floods. Rain water on top of the storm surge may add to the fury of the storm.
• Storm Surge: A Storm surge can be defined as an abnormal rise of sea level near the coast caused by a severe tropical cyclone; as a result of which sea water inundates low lying areas of coastal regions drowning human beings and life stock, causes eroding beaches and embankments, destroys vegetation and leads to reduction of soil fertility.
• Regional Climate: Tropical cyclones can quickly change the environment of the affected areas. They can bring warmer air into hot places. This makes the atmosphere feel very sticky and muggy and rises the temperature dramatically. This can cause heat strokes and other heat related illness to children and the elderly after the storm which is not good.
• Fishing and livelihood: Loss of habitat and Loss of juveniles and brood fishes. Loss of livelihoods of farmers and fishermen: Statistics show that the global average annual losses from cyclones and storm surges are estimated at US$ 80 billion. Small fishermen with no state-of-the-art technology are usually advised to stay off the seas before and during the cyclones.

Measures to tackle such incidences:

• The National Cyclone Risk Mitigation Project (NCRMP), to be implemented with financial assistance from the World Bank, is envisaged to have four major components:
  (i) Component A: Improvement of early warning dissemination system by strengthening the Last Mile Connectivity (LMC) of cyclone warnings and advisories.
  (ii) Component B: Cyclone risk mitigation investments.
  (iii) Component C: Technical assistance for hazard risk management and capacity-building.
  (iv) Component D: Project management and institutional support.
• These components are highly interdependent and have to be implemented in a coherent manner.
• The NDMA had come up with its National Guidelines of Management of Cyclones in 2008. The basic premise of these guidelines is that the mitigation has to be multi-sectoral.
• Developing Integrated Coastal Zone Management (ICZM) frameworks for addressing the sustainability and optimal utilisation of coastal resources as also cyclone impact minimisation plans.
• Ensuring cyclone resistant design standards are incorporated in the rural/ urban housing schemes in coastal areas
• Implementing coastal flood zoning, flood plain development and flood inundation management and regulatory plans.
• Coastal bio-shields spread, preservation and restoration/ regeneration plans.
• There is a need for private sector participation in designing and implementing policies, plans, and standards.
• Need of Disaster Management program to be inclusive including women, civil society, and academia.

Conclusion:

In Indian waters, cyclonic storms are associated with heavy rains, thunderstorms, high tides and intense winds that cause shocking destruction in coastal areas. The increase in the frequency of tropical cyclones over the Arabian Sea can result in a massive loss of lives, livelihood and costal ecology. India should prepare to mitigate and deflect the destruction caused by Cyclones. We need to employ technology, strict following of command structure and most importantly the participation and cooperation of local communities in the affected area.