CYCLONES are atmospheric disturbances and are formed around a low-pressure area. It is distinguished by swift and often destructive air circulation.
Geographically, it is classified into:
- Tropical cyclones
- Extratropical/Temperate cyclones
Tropical cyclones are of thermal origin. That is, it owes its origin to the warmness of ocean water. It occurs between Tropic of Cancer and Tropic of Capricorn. Whereas, the temperate cyclone is of frontal origin.
India with a long coastline of 7516.16 km is one of the worst affected regions, where it is exposed to around 10% of tropical cyclones in the world.
- It is an intense low-pressure centre associated with the convergence of wind rotating inwards to the low-pressure point forming a closed cyclonic vortex. Coriolis force and the rapid inward circulation to the low-pressure area is the reason behind the formation of the cyclonic vortex.
- Center of the low-pressure area is called EYE region where the atmosphere is calm. But the area around the eye region (eye-wall) is associated with violent movement of wind.
- It begins as a low-pressure area to a super cyclone depending on the speed of the wind. (check table below)
- It consists of cumulonimbus cloud with torrential rainfall.
According to the wind speed, Tropical Cyclones are classified in to :
Favourable conditions for Cyclones
- A low-pressure condition where I.T.C.Z forms 5 to 8 degree away from the equator.
- Sea surface temperature should be more than 27-degree Celsius.
- An adequate amount of vapour supply through evaporation.
- Differential heating of land and sea.
- Strong anticyclonic divergence in the upper atmosphere.
Effects of cyclones
- Strong winds/Squalls: Through high-speed winds, cyclones cause severe damage to the infrastructure. Installations, dwellings, communication system etc. get destroyed resulting in loss of life and property.
- Torrential rains and Inland flooding: Continuous rains cause floods resulting in loss of shelter. Also, heavy rains due to cyclone cause landslides, soil erosion and weaken the embankments.
- Storm surge: An abnormal rise in sea level near the coast due to severe tropical cyclone results in the drowning of low lying areas in the coastal region. It results in loss of lives, destruction of vegetation and the salt content in seawater reduces the soil fertility.
- Majority of the cyclones affecting India originates from the Bay of Bengal striking the eastern coast. The ratio of occurrence of cyclone between the Bay of Bengal and Arabian sea is approximately 4:1. This is because of less salinity, which is due to more inflow of freshwater and high sea surface temperature in the Bay of Bengal.
- Cyclones in India occurs during the month of May, June, October, and November.
- Cyclones like Nada, Varda, Hudhud, Phailin etc. caused loss of property in the eastern part of India. Recently, a severe cyclonic storm Ockhi resulted in the loss of lives and damage to properties in Tamil Nadu and Kerala.
Current Situation of Disaster Preparedness and Management in 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 theHome ministry, 8% of total area in India is prone to cyclones.
- Indian Meteorological Department(IMD) is the nodal agency for early warning of cyclones and floods.
- Natural Disaster Management Authority is mandated to deal with the disaster management in India. It has prepared National Guidelines on Management of Cyclone.
- National Cyclone Risk Mitigation Project (NCRMP) was launched by Home ministry to upgrade the forecasting, tracking and warning about cyclones in states.
- National Disaster Response Force(NDRF) has done a commendable performance in rescuing and managing relief work.
- National Disaster Response Reserve (NDRR)– a fund of 250 crores operated by NDRF for maintaining inventory for an emergency situation.
- In 2016, a blueprint of National Disaster Management Planwas unveiled to tackle disaster. It provides a framework to deal with prevention, mitigation, response and recovery during a disaster. According to the plan, Ministry of earth science will be responsible for disaster management of cyclone. By this plan, India joined the list of countries which follow the Sendai Framework For Disaster Risk Reduction 2015-2030.
- Due to increased awareness and tracking of Cyclone, the death toll has been reduced substantially. For example, Very severe cyclone Hudhud and Phailin claimed lives of around 138 and 45 people respectively, which might have been more. It was reduced due to the early warning and relocation of the population from the cyclone-hit areas. Very severe cyclone Ockhi claimed many lives of people in Tamil Nadu and Kerala. This was due to the unprecedented change in the direction of the cyclone.
- But the destruction of infrastructure due to cyclonic hit is not been reduced which leads to increase in poverty due to the economic weakening of the affected population.
Problems in Disaster Preparedness and Management
- Historically from the British period onwards disaster management in India is largely confined to post-disaster relief works. It is more about management than prevention.
- One-third of the population in India lives in the coastal area. Most of them are marginalized people who are ill-prepared and unable to cope up with disaster.
- India considers post-disaster response as an important activity. Hence institutional system, manuals, policy, programs are designed to address this concerns. Redefining this is not yet complete.
- There is lack of proper coordination between the central and state government and its agencies.
- The warning of a cyclone is not properly communicated between the concerned agencies. In many cases, the warning is not taken seriously by the agencies which cause delayed effort for prevention of a disaster. This was evident in the recent Ockhi cyclone disaster.
- Lack of awareness of people about the impact and magnitude of the disaster.
- Mining and other industries in the ecologically sensitive area, lack of compliance with zoning and building regulation codes is increasing the death toll.
- Indian laws follow the international norms which make it illegal for small fishing vessels to carry communication equipment that could help in saving lives during a disaster.
- There is also a lack of coordination between the local communities for search and rescue missions.
- There is a need of harmonizing the national and local level disaster resilient bylaws, land use zoning, resource planning, early warning system establishments and technical competence.
- The government should take commonalities from success stories and institutionalize it. For example, Built Back Better Program of Gujarat government after 2001 earthquake.
- Disaster Risk Reduction should be an important aspect of global poverty reduction initiatives.
- Moving from a risk blind approach to a risk-informed decision when it comes to investments.
- There should be a Disaster Risk Audit for the future developmental project for both public and private entities.
- Disaster Risk Reduction program should be more people-centric.
- 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.
- State governments should increase their engagements in scientific research institution for a better formulation of policies.
Nature is unpredictable. Nothing in the world can withstand its fury. Natural disaster comes without warning. India should prepare to mitigate and deflect the destruction caused by Cyclones. For this India need to employ more technology, strict following of command structure and most importantly the participation and cooperation of local communities in the affected area.