Cyclones : news and updates


Improving Resilience to Cyclones Disasters in India

Read More

Synopsis – The Government needs to ensure fiscal rehabilitation for improving resilience to Cyclones disasters.

Introduction-
  • The Indian subcontinent is among the worst affected regions of the world when it comes to tropical cyclones. It is due to its 4,670-mile coastline, where a large percentage of the country’s population lives.
  • Despite all the planning for reducing risk and forecasting cyclone paths still, cyclones have been incredibly destructive as seen in the case of Cyclone YAAS. Thousands have lost houses and property.
  • There is still a lot of work to do. It is in terms of preserving assets and developing fiscal tools to assist people to rebuild their lives.
What are the reasons behind frequent cyclones disasters in India?

Extreme tropical storm precipitation events and accompanying inland floods may become more common. Because the climate continues to warm due to increasing human activities.

  • Rising Ocean temperatures – Warmer ocean temperature makes atmospheric and ocean conditions favorable for the intensification of cyclones.
    • It could intensify the speed of the winds by up to 10%. It will result in an increase of 10-15% in precipitation. Both of these factors could cause more flooding and widespread damage.
  • Rise in seas level due to global warming.

Impact of recent cyclones- According to the World Meteorological Organization (WMO) report on the State of Global Climate 2020

  • The economic losses caused by cyclone Amphan amounts to about $14 billion.
  • Around 2.4 million people were displaced in India, mainly in West Bengal and Odisha.
Ways to address the risk of cyclones and other extreme events

Following cyclone Amphan, the West Bengal government faces allegations of irregularities and corruption in the distribution of financial relief. Governments are in the best position to compensate people against the cost of disasters by spreading the cost across the population. Thus,

  • Government should ensure proper distribution of funds without corruption and mismanagement.
  • It should make citizens, members in a social insurance model.
  • Rebuilding should be green and follow a build-back better approach. It is necessary, considering the negative impact of climate change on tropical cyclones.

Source- The Hindu

Posted in 9 PM Daily Articles, daily news, Daily News Updates, PUBLICTagged

Very Severe “Cyclone Yaas” hits the coastal areas of Odisha and West Bengal

Read More
What is the News?

Cyclone Yaas hit the coastal areas of Odisha and West Bengal. Upon landfall, the cyclone weakened.

About Cyclone Yaas:
  • Cyclone Yaas is a Tropical Cyclone. It has been named by Oman. Yaas means a tree bearing fragrant flowers.
  • Cyclone Yaas is the first cyclonic storm to develop over the Bay of Bengal in 2021.
  • Cyclone Yaas crossed the northern Odisha coast around 20 km south of Balasore at its peak intensity as a very severe cyclonic storm.

Click Here to Read how Cyclones are Named

upcoming Cyclone names

Classification of Cyclones: The Indian Meteorological Department(IMD)’s criterion to classify the cyclones is based upon the method adopted by the World Meteorological Organisation(WMO). The classification is:

Type of Disturbances (and Associated Wind Speed in the Circulation):
  • Firstly, Low-pressure Area: Wind Speed less than 17 knots (<31 kmph)
  • Secondly, Depression: 17 to 27 knots (31 to 49 kmph)
  • Thirdly, Deep Depression: 28 to 33 knots (50 to 61 kmph)
  • Fourthly, Cyclonic storm: 34 to 47 knots (62 to 88 kmph)
  • Fifthly, Severe Cyclonic Storm: 48 to 63 knots (89 to 118 kmph)
  • Sixthly, Very Severe Cyclonic Storm: 64 to 119 knots (119 to 221 kmph)
  • Seventhly, Super Cyclonic Storm: 119 knots and above (221 kmph and above).

Source: The Hindu

 

Posted in Daily Factly articles, daily news, Daily News Updates, Miscellaneous, PUBLICTagged

Rising Cyclone Intensity and Frequency due to Micro-Climatic Changes

Read More

Synopsis: According to the Council on Energy, Environment and Water(CEEW) report the cyclone frequency has doubled after 2005 in India. Micro Climatic Changes are contributing to this change.

Key Findings of the report:
  • In the last 50 years, India has recorded a 12-fold increase in the number of cyclonic events such as extreme rainfall, floods, sea-level rise, and thunderstorms.
  • The frequency of extreme weather events is far more severe on the western coast of India. The expectations are for it to increase further in the coming decades.
  • Concern: This is a worrying sign for India. This is because Arabian Sea cyclones have been impacting India’s west coast at the rate of one per year since 2018. This frequency is not seen before in five decades.
Reasons behind the increasing intensity of cyclones on western coastal areas
  • Microclimatic changes triggered by local climate change drivers are the reasons behind it. Changes include land-use-surface change, deforestation, encroachments upon wetlands and water bodies, which are contributing to this change.
  • These factors are contributing to excessive heating of land areas. This heat is further pulled into the ocean, which is in excess of the heating of oceans due to global warming. It intensifies storms into cyclones.
Vulnerable States:

 Gujarat:

  • In Gujarat, as many as 29 districts are vulnerable to extreme climate events. These extreme events have increased three-fold between 1970 and 2019.
  • Moreover, Gujarat is becoming increasingly common to have droughts in one set of districts and floods in other sets of districts in the same season.
Other States:
  • Maharashtra: The analysis also points to Maharashtra as a vulnerable state which has been affected most by droughts. The state has seen a seven-fold increase in the past 50 years affecting more than 80% of its districts.
  • Goa: There has been a four-fold increase in storm surge and cyclone events in the last 50 years in Goa. Cyclone-associated events have also increased six-fold since 2005.
Initiatives by the government:
  • The Government of India launched the second phase of the National Cyclone Risk Mitigation Project in 2015.
  • The programme is being implemented successfully in the Eastern coast of India and especially states like Odisha.
  • However, the projects along the western coast are lagging. The projects were to be completed by 2019, but the states here have missed this deadline, Hence, the deadline has now been extended to 2022.
Recommendations:
  • Climate-vulnerable states such as Gujarat need to focus more on building climate resilience, especially at the local and regional levels.
  • States must invest in cost-effective (and nature-based) resilient infrastructure.
  • Governments should develop decentralised capacity to respond to climate shocks and design salient public information campaigns to prepare vulnerable communities against climate risks.
  • At the national level, there is a requirement for a Climate Risk Commission with statutory status. A Climate Risk Atlas with district-level information should support the commission.
  • New insurance schemes should be launched to provide the safety net for livelihoods and not just the saving of lives.

Source: Indian Express

Posted in 9 PM Daily Articles, daily news, Daily News Updates, PUBLICTagged

Steps and Suggestions to Handle Cyclone related Disasters

Read More

Synopsis: Precise forecasts and resilience-building are very important in handling severe cyclones.

Introduction 
  • Cyclone Tauktae has become a severe cyclonic storm. It is throwing huge volumes of water all along the west coast. It caused loss of life in Kerala, Karnataka, Goa, Maharashtra, and Gujarat, before fading overland.
  • Thousands of people had to be evacuated to safe locations. This year’s pre-monsoon season is posing a double risk. People are stuck between a fast-spreading virus variant and a pounding storm. 
  • Many coastal residents would have gone through a similar experience last year, when the severe cyclonic storm, Nisarga, moved landwards from the Arabian Sea.
Initiatives and suggestions 

India has taken many steps in forecasting, disaster mitigation.  However, it needs to develop greater expertise in crafting policies to increase resilience among communities. Only then it would be prepared to handle cyclones. 

  1. Firstly, the India Meteorological Department (IMD) introduced an impact-based cyclone warning system from the October-December season aimed to reduce economic losses last year. It focussed on districts and specific locations. It also incorporated factors such as population, infrastructure, land use, and settlements.
  2. Secondly, the IMD claimed that its accuracy of forecasts is now better. For instance, in plotting landfall location. This is a promising approach (along with ground mapping of vulnerabilities) to avoid loss of life and destruction of property. 
  3. Thirdly, the importance of accurate early warnings cannot be over stressed. The Arabian Sea has become a major source of severe cyclones. Their intensity is heightened by a long-term rise in sea surface temperatures related to pollution over South Asia and its neighbourhood.
  4. Lastly, climate-proofing of lives and dwellings should be a high priority now. Climate proofing requires a multi-sectoral approach: 
    • To build durable homes of suitable design.
    • Create adequate storm shelters.
    • Provide accurate early warnings.
    • Ensure financial protection against calamities through insurance for property and assets. Governments must rise up to this challenge. 

Source: click here

 

“Cyclone Tauktae” expected to hit Gujarat

Posted in 9 PM Daily Articles, daily news, Daily News Updates, PUBLICTagged

Why Arabian Sea is transforming into a New Cyclonic Hotbed? – Explained, Pointwise

Read More
Introduction

The Arabian Sea used to be cyclone shy! But it is changing now, and changing fast!

Cyclones are among the most devastating extreme weather events that India faces every year. The strong winds and heavy rains that accompany cyclones cause immense loss of life and property along the coastline of India.  Approximately 1.4 lakh people died by cyclones, floods, and other weather extremes during the past five decades.

The recent formation of Cyclone Tauktae makes 2021 the fourth consecutive year to witness an Arabian Sea cyclone during the pre-monsoon season (April–June). The changing climate and rising global warming have converted the Arabian Sea into a new hotbed for cyclonic activities. Earlier the majority of the cyclones used to occur in the Bay of Bengal.

Current Scenario
  • Cyclone Tauktae developed over the Arabian Sea on May 14, 2021, and got converted into a very severe cyclonic storm (VSCS) on May 16, 2021. It is expected to hit southern Gujarat on May 18, 2021. 
  • In recent years, strong cyclones have been developing on the Arabian Sea more frequently than earlier.
About Tropical Cyclones
  • They are violent storms that originate over oceans in tropical areas.
  • They create a whirl in the atmosphere with very strong winds circulating around it. The direction is anticlockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
  • The pressure gradient falls towards the center from all directions and therefore winds try to converge towards the center from all directions.
  • They develop in the North Indian Ocean region (Bay of Bengal and Arabian Sea) during the pre-monsoon and post-monsoon (October to December) periods. May-June and October-November are known to produce cyclones of severe intensity that affect the Indian coasts.
  • It is anticipated that around 76 per cent of India’s coastline is susceptible to cyclones and tsunamis.
  • Conditions for Formation of Tropical Cyclones:
    • A consistent source of heat as tropical cyclones are thermally induced low-pressure systems.
    • Large sea surface with a temperature higher than 27° C which is possible only during the late summers i.e. September, October, and November
    • Presence of the Coriolis force. It is the result of the earth’s rotation and deflects objects to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.
    • 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.
Past Trend of Cyclonic Activities
  • The Arabian Sea has been comparatively less prone to cyclonic storms than the Bay of Bengal. In the usual course, there was an occurrence of one extremely severe cyclone every four-five years in the Arabian Sea.
  • During the period 1891-2000, nearly 308 tropical cyclones crossed the east coast, of which 103 were severe in intensity. Similarly, 48 cyclones crossed the west coast of which 24 were severe. 
 Reasons behind past trends
  • First, high sea surface temperatures along with high humidity in the Bay of Bengal triggers extremely strong cyclones.
  • Second, sluggish winds along with warm air currents in the Bay of Bengal keep temperatures relatively high.
  • Third, the constant inflow of freshwater from the Ganga and Brahmaputra rivers makes it impossible for the warm water to mix with the cooler water below.
  • Fourth, cyclonic winds easily move into the Bay of Bengal due to the presence of moisture sources from rivers and the absence of any large landmass.
  • Fifth, the Arabian Sea receives stronger winds that help dissipate the heat, and the lack of constant freshwater supply helps the warm water mix with the cool water thereby reducing the temperature. 
    • Almost 50% of the storms don’t sustain as the west-central and the north Arabian Sea have a colder sea temperature than other adjacent regions. 

However, this trend is changing, with a greater number of cyclones being developed in the Arabian Sea.

Reasons behind increasing cyclonic activities in the Arabian Sea
  • Annually, five cyclones on average used to form in the Bay of Bengal and the Arabian Sea combined. Among these, four develop in the Bay of Bengal and one in the Arabian Sea.
  • Previously, tropical cyclones in the Arabian Sea were restricted to Gujarat. However, now even Kerala and Karnataka have also become more vulnerable to cyclones. A recent example is ‘Ockhi’.
  • Tauktae is the fourth cyclone in consecutive years to have developed in the Arabian Sea. Cyclone Mekanu hit Oman in 2018, Cyclone Vāyu struck Gujarat in 2019 and Cyclone Nisarga hit Maharashtra in 2020.
  • Apart from frequency, a rise in the intensification rate is also observed. All these cyclones since 2018 have been categorised either ‘Severe Cyclone’ or above.
    • Tauktae took only 2 days to become VSCS while Cyclone Mekanu and Cyclone Nisarga had developed slower, taking 4 and 5 days respectively.  
Reasons behind changing trends
  • First, sea surface temperatures in the Arabian Sea have increased rapidly during the past century due to global warming. Temp. now is 1.2–1.4 °C higher than the temperature witnessed four decades ago. These warmer temperatures support active convection, heavy rainfall, and intense cyclones.
  • Second, the rising temperature is also enabling the Arabian Sea to supply ample energy for the intensification of cyclones. Currently, seawater up to depths of 50 metres has been very warm that allowed Cyclone tauktae to become a VSCS in only 2 days.
  • Third, the Arabian Sea is also providing conducive wind shear for cyclones. For instance, a higher level easterly wind drove the depression of Cyclone Ockhi from the Bay of Bengal to the Arabian Sea.
  • Fourth, greater occurrence of El Niño Modoki. It is a climate phenomenon that means ‘pseudo El Niño’ and creates conditions that are not conducive for cyclogenesis in the Bay of Bengal. However, this condition is conducive for the formation of cyclones in the Arabian Sea.
    • El Nino is associated with suppressing cyclone formation in the Arabian Sea.
Concerns associated with changing trends
  • Covid management: There is a concern about the impact of the cyclonic storm on the battle against Covid-19. The rain and flooding may set back social distancing and other necessary measures at evacuation centres and relief camps.
  • Delay in Monsoon: The cyclone Tauktae is expected to interfere with the normal progression of the Indian Monsoon by sucking all the moisture from the monsoon winds towards itself.  The strong low-pressure areas at their core induce the surrounding winds to rush towards them.
  • Rise in Extreme Rainfall events: Widespread extreme rainfall events that cause floods have also increased by threefold over India, in response to Arabian Sea warming. This has deeply impacted the lives, livelihood, infrastructure and ecology of the region.
  • Forecasting Challenge: The new trend is encouraging more and more rapid intensification of cyclones. State-of-the-art cyclone models are unable to pick this rapid intensification because they do not incorporate the ocean dynamics accurately. 
Initiatives towards Cyclones
  •  Government is carrying out a National Cyclone Risk Mitigation Project (NCRMP) with the help of the World Bank to upgrade cyclone forecasting, tracking, and warning systems in India
  • The government is also implementing the Integrated Coastal Zone Management Project (ICZMP) to improve national capacity for the implementation of comprehensive coastal management in India.
  • Lastly, Government also separated Structural (includes construction) and non-structural measures for effective disaster management of cyclones.
Suggestions
  • The cyclones must be closely monitored at higher resolution and accuracy using on-site platforms such as buoys and moorings.
    • A buoy is a type of object that floats in water and is used in the middle of the seas as locators or as warning points for ships.
    • A mooring is any permanent structure to which a vessel may be secured.
  • The Indian National Centre for Ocean Information Services (INCOIS) must be provided with greater autonomy, finance, and human resources. This would improve the collection and dissemination of data on cyclonic events.
  • There must be an incorporation of the global warming signals in the weather models that can help tackle the challenges of intense cyclones in the future.
Conclusion

Climate projections indicate that the Arabian Sea will continue warming due to increasing carbon emissions, resulting in more intense cyclones in the future. This calls for strengthening the disaster management framework in consonance with the Sendai Framework for Disaster Risk Reduction 2015-2030.

Posted in 7 PM, PUBLICTagged

“Cyclone Tauktae” expected to hit Gujarat

Read More
What is the News?

Cyclone Tauktae (pronounced Tau-Te) is expected to hit southern Gujarat of the country.

About Cyclone Tauktae:
  • Cyclone ‘Tauktae‘ name was suggested by Myanmar. Tauktae means a highly vocal lizard gecko.
  • This cyclone has been classified as a very severe cyclonic storm (VSCS).
  • The Cyclone has been developed in the Arabian Sea.
Why is Cyclone Tauktae unique?
  • Cyclone Tauktae will be the first cyclonic storm along the Indian coast in the year 2021.
  • This will also be the fourth cyclone in consecutive years to have developed in the Arabian Sea, that too in the pre-monsoon period (April to June).
    • All these cyclones since 2018 have been categorised as either ‘Severe Cyclone’ or above.
How are cyclones named?
  • Cyclones are officially named by one of the World Meteorological Organization’s (WMO) warning centres based across the globe.
Naming cyclones in the Bay of Bengal and Arabian Sea:
  • The WMO/United Nations Economic and Social Commission for Asia and the Pacific (ESCAP) Panel on Tropical Cyclones (PTC) names the cyclones for this region since 2000.
  • The panel includes 13 countries –– India, Bangladesh, Myanmar, Pakistan, the Maldives, Oman, Sri Lanka, Thailand, Iran, Qatar, Saudi Arabia, United Arab Emirates and Yemen.
  • Each country sent in suggestions to the WMO/ESCAP Panel. After this, the panel finalizes the list alphabetically country-wise starting with Bangladesh followed by India, Iran, Maldives and so on.
Significance of Naming of a cyclone:
  • Firstly, it helps in the quick identification of storms in warning messages
  • Secondly, names are presumed to be far easier to remember than numbers and technical terms.
  • Thirdly, giving names to cyclones makes it easier for the media to report on tropical cyclones,
  • Fourthly, it heightens interest in warnings and increases community preparedness

Source: Indian Express

 

How Tropical cyclones are formed?

Posted in Daily Factly articles, daily news, Daily News Updates, Miscellaneous, PUBLICTagged

Implementation of “National Cyclone Risk Mitigation Project(NCRMP)”

Read More

What is the News?

The government of India has informed the Lok Sabha about the implementation of the National Cyclone Risk Mitigation Project(NCRMP).

About National Cyclone Risk Mitigation Project(NCRMP):

  • Firstly, it was launched by the Ministry of Home Affairs with the support of the World Bank. It addresses the cyclone risks in the country.
  • Secondly, its aim is to undertake suitable structural and non-structural measures to mitigate the effects of cyclones in the coastal states and UTs of India.
  • Thirdly, its objectives are:
    • Improving early warning dissemination systems
    • Enhancing the capacity of local communities to respond to disasters
    • Improving access to emergency shelter, evacuation, and protection against wind storms, flooding, and storm surge in high areas
    • Strengthening Disaster Risk Management(DRM) capacity at central, state, and local levels.
  • Implementation: National Disaster Management Authority(NDMA) in coordination with participating State Governments and the National Institute for Disaster Management (NIDM).
  • Coverage: The Project has identified 13 cyclone-prone States and Union Territories(UTs) with varying levels of vulnerability. These States/UT have further been classified into two categories:
    • Category I: Higher vulnerability States namely Andhra Pradesh, Gujarat, Odisha, Tamil Nadu, and West Bengal.
    • Category II: Lower vulnerability States i.e. Maharashtra, Karnataka, Kerala, Goa, Pondicherry, Lakshadweep, Daman and Diu, Andaman, and the Nicobar Islands.

Source: PIB

Posted in Daily Factly articles, Miscellaneous, PUBLICTagged

How Tropical cyclones are formed?

Read More

News: Cyclone Burevi has weakened into a deep depression as its interaction with a landmass in Tamil Nadu has slowed its movement and intensity.

Cyclonic disturbances are rapid weather systems, which include weather depressions, deep depressions, and tropical cyclones (of severe, very severe, extremely severe, and super cyclonic storms depending on their intensity).

What is Tropical cyclone Burevi ?

Tropical cyclones are violent storms that originate over oceans in tropical areas and move over to the coastal areas bringing about large-scale destruction caused by violent winds, very heavy rainfall, and storm surges.

Cyclones create a whirl in the atmosphere with very strong winds circulating around it in an anti-clockwise direction in the Northern Hemisphere and in a clockwise direction in the Southern Hemisphere.

The pressure gradient falls towards the center from all directions and therefore winds try to converge towards the center from all directions. The air blows inwards in an anticlockwise direction in the northern hemisphere and clockwise in the southern hemisphere.

Conditions for formation of Cyclones

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

  1. A consistent source of heat as tropical cyclones are thermally induced low-pressure systems.
  2. Large sea surface with a temperature higher than 27° C which is possible only during the late summers i.e. September, October, and November
  3. Presence of the Coriolis force.
  4. Small variations in the vertical wind speed.
  5. A pre-existing weak low-pressure area or low-level-cyclonic circulation;
  6. Upper divergence above the sea level system.

Structure of Tropical Cyclone

The structure of a Tropical Cyclone is typically a massive cumulonimbus cloud with rapidly rising air spiraling upwards at the margins of the eye. An eye is a region of calm with subsiding air. Around the eye is the Eyewall, where strong spiraling winds ascends and the height can reach up to the tropopause.

Tropical cyclones are formed by the following parts:

Eye:  

The eye is the center of cyclones which is characterized by a calm area, sinking, and light wind. The eye is the calmest part of the Cyclone structure.

Conservation of angular momentum and centrifugal force are the reasons behind its formation.

Eyewall:

A band around the eye of the greatest wind speed, where clouds reach the highest and precipitation is the heaviest. The heaviest wind damage occurs where a hurricane’s eyewall passes over land.

Rain bands:

Curved bands of clouds and thunderstorms that trail away from the eyewall in a spiral fashion. These bands are capable of producing heavy bursts of rain and wind. Sometimes gaps are found between spiral rain bands, where no impact (wind or rain) of cyclones are found.

Formation of Tropical Cyclones

Cyclone Structure

  • As mentioned in the conditions, air temperature higher than 27° C with an abundant and turbulent transfer of water vapor to the overlying atmosphere (air) by evaporation is required for the formation of Cyclones, which is facilitated by direct insolation.
  • As the low-pressure area is created over sea pockets and high pressure on the surrounding areas, air starts to flow from the high-pressure area to low-pressure pockets.
  • The Coriolis force causes the wind to spiral around a low-pressure area. As the presence of Coriolis force is negligible in the equatorial belt between 5 degrees north and 5 degrees south latitudes, hence cyclonic systems do not develop in this region.
  • Heated sea surface starts to heat the air over that leading to air moving up and away from the ocean surface due to convection, it leaves less air near the surface. Cool Air from the surrounding areas rushes towards the empty area to fill it, which after reaching there gets heated and picks moisture and starts rising upwards. It creates the cycle of air moving in and up.
  • As the moist air rises up, it starts cooling with the altitude (temperature falls with the height), and the process of condensation starts. It results in the release of the latent heat of condensation. The latent heat of condensation is what drives the storm and leads to the formation of clouds.
  • The energy that intensifies the storm, comes from the condensation process in the towering cumulonimbus clouds, surrounding the center of the storm (Eye).
  • With the increasing altitude, the air cools down to an extent at tropopause where it fails to rise any further and starts to diverge outside horizontally.
  • The whole system of clouds and wind spins and grows, fed by the ocean’s heat and water evaporating from the ocean surface. As the storm system rotates faster and faster, an eye forms in the center.
  • A mature tropical cyclone is characterized by the strong spirally circulating wind around the center, called the eye. The diameter of the circulating system can vary between 150 and 250 km.
  • Rain bands regions with cumulonimbus clouds are created, facilitating intense rainfall in that region. Cloud formation is dense at the center and density decrease towards the outside.

Conditions that slow or end Cyclones

  • With a continuous supply of moisture from the sea, the storm is further strengthened. On reaching the land the moisture supply is cut off and the storm dissipates. The place where a tropical cyclone crosses the coast is called the landfall of the cyclone.
  • Another condition that slowdown or ends a Cyclone is when dry, cool air is suddenly present in the system, which reduces the possibility of convection to keep the storm going.

Why More Cyclones are formed in Bay of Bengal?

There are other coastlines around the world that are vulnerable to surging storms – the Gulf Coast of Louisiana, for example – but the “north coast of the Bay of Bengal is more prone to catastrophic surges than anywhere on Earth”.

Both the Bay of Bengal and the Arabian Sea are prone to Cyclonic storms, but Cyclonic activities are more intense and frequent in Bay of Bengal Compared to the Arabian Sea

  • High sea surface temperatures along with high humidity due to higher rainfall in the Bay of Bengal, triggers extremely strong cyclones.
  • Sluggish winds, along with warm air currents in the Bay of Bengal keep temperatures relatively high.
  • The supply of constant inflow of fresh water from the Ganga and Brahmaputra rivers makes it impossible for the warm water to mix with the cooler water below.
  • Cyclonic winds easily move into the Bay of Bengal due to the presence of moisture source from rivers and the absence of any large landmass unlike the Arabian Sea, where Cyclones usually weaken due to the presence of Western Ghats.
  • Whereas Arabian Sea receives stronger winds that help dissipate the heat, and the lack of constant fresh water supply helps the warm water mix with the cool water, reducing the temperature.

Classification of storms

Indian Meteorological Department (IMD), which classifies the low pressure systems in the Bay of Bengal and the Arabian Sea on the basis of capacity to damage, which is adopted by the WMO.

tropical cyclone classification

Benefits of Tropical Cyclones:

Although Tropical cyclones are known for the destruction they cause, when they strike, they also bestow certain benefits to the climatic conditions of that area such as

  • Relieve drought conditions: By bringing rain to the coastal areas, cyclones relieve the drought-like conditions in the surrounding areas.
  • Maintain equilibrium in the Earth’s troposphere: They Carry heat and energy away from the tropics towards temperate latitudes, thus helps in maintaining an equilibrium of the troposphere.
  • Cyclones help in maintaining a relatively stable and warm temperature worldwide.

Causes of destruction caused by Cyclones:

There are three elements associated with cyclones that cause destruction during its occurrence. These are:

Strong Gusts/Squall:
    • These are very strong winds that accompany a cyclonic storm damages installation, dwellings, communications systems, trees, resulting in loss of life and property.
  • Gusts: These are short but rapid bursts in wind speed. These are the main cause of damage. Gusts are generally short-lived.
  • Squalls: A squall is a strong rise in wind speed which generally lasts for some time. Squalls generally associated with the bands of thunderstorms.
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 is a serious problem for the people which become shelterless due to cyclone.
    • Heavy rainfall from a cyclone is usually spread over a wide area and causes large-scale soil erosion and weakening of embankments.
Storm Surge:
  • It can be defined as an abnormal rise of sea level near the coast caused by a severe tropical cyclone;
    • Seawater inundates low-lying areas of coastal regions drowning human beings and life stock, causes eroding beaches and embankments, destroys vegetation, and leads to a reduction of soil fertility.

Apart from these Cyclones also create destructions such as:

    • Sudden Change in Regional climate: The ability of cyclone to bring in warmer air is high. So, the elderly and children in those areas have a high vulnerability to develop heat-related problems such as heat strokes.
    • Loss of Livelihood: The majority of the coastal people generally depend on fishing which is completely halted by cyclones.
    • Loss of economy: The economic loss is in multifront from infrastructure loss, relief packages to people, etc.

Government Initiatives:

  • Government is carrying out a National Cyclone Risk Mitigation Project (NCRMP) with the help of the World Bank to upgrade cyclone forecasting, tracking, and warning systems in India
  • Government is also implementing the Integrated Coastal Zone Management Project (ICZMP) to improve national capacity for the implementation of comprehensive coastal management in India.
  • Government also separated Structural(includes construction) and non-structural measures for effective disaster management of cyclones
  • Solutions:
  • The government should consider the NDMA Guidelines for the management of cyclones:
  • Ensemble Warning System(EWS): Establish EWS involving observations, predictions, warnings, and customized local level advice for decision-makers (national, state, district level) to manage the impact of the cyclone (Read more about EWS)
  • Commissioning of Aircraft Probing of Cyclone (APC): Guidelines calls for the combination of manned and Unmanned Aerial Vehicles (UAV) for critical observational data gaps.
  • Cyclone Disaster Management Information System (CDMIS): Establishing a comprehensive department for coverage of all management information and provide online services to the departments of Disaster management.
  • Specifying the roles and responsibilities in institutionalizing Cyclone risk mitigation with Developmental planning.
  • Community-Based Disaster Management (CBDM): Guidelines asked to launch such activities in all villages of the 84 districts vulnerable to cyclones.

Way forward:

  • With the adverse Climate Change risks posted by IPCC reports the only option for India is to better preparedness for the disaster with better urban planning, community awareness, etc.
Posted in 7 PMTagged , , ,

Cyclone Burevi

Read More

News: Cyclone Burevi is heading towards the Tamil Nadu(TN) coast after crossing Sri Lanka.

Facts:

  • Cyclonic Burevi: It is a tropical cyclone formed over southwest Bay of Bengal.It is expected to bring heavy rainfall over south Tamil Nadu and south Kerala.
  • Named by: The name “Burevi” was suggested by the Maldives.

Additional Facts:

  • Tropical Cyclones: These are storms that originate and intensify over warm tropical oceans.They are intense low pressure areas with very strong winds circulating around it in anti-clockwise direction in the Northern Hemisphere and in clockwise direction in the Southern Hemisphere.
  • Different Names: Tropical Cyclones are known by different names in different regions:
    • Cyclones in Indian Ocean
    • Hurricanes in Atlantic
    • Typhoons in Western Pacific in South China Sea
    • Willy-Willies in Western Australia
  • Conditions: The conditions favourable for the formation and intensification of tropical cyclones are:
    • Large sea surface with temperature higher than 27° C;
    • Presence of the Coriolis force enough to create a cyclonic vortex
    • Small variations in the vertical wind speed;
    • A pre-existing weak low-pressure area or low-level-cyclonic circulation is must for cyclone formation in tropics
    • Upper divergence above the sea level system

How Tropical cyclone are formed?

Posted in 9 PM Daily Articles, daily news, Daily News UpdatesTagged ,

Cyclone Nivar: All about tropical cyclones

Read More

This article has been created based on The Hindu Editorials:  Storm warnings: On weather forecast and Cyclone Nivar appeared on 27th November 2020.

Introduction

According to the India Meteorological Department (IMD), Cyclone Nivar, which crossed the TN coast as a very severe cyclonic storm with wind speeds of 120 kmph and rain-filled, further weakened as it moved inland.

The storm system is likely to move northwestwards and weaken into low pressure. Subsequently, Cyclone Nivar weakened into a cyclonic storm and further into a deep depression, centered about 50 km west-southwest of Tirupati.

Cyclone Nivar is the second cyclone to form over the Bay of Bengal this year after Super Cyclone Amphan.

Read about Amphan and few basics in ForumIAS blog by clicking here

India Meteorological Department (IMD)

  • IMD is the principal agency for all matters relating to meteorology and allied subjects such as weather forecasting and seismology etc.
  • In the year 1875, the Government of India established the India Meteorological Department, bringing all meteorological work in the country under a central authority.
  • Mr. H. F. Blanford was appointed Meteorological Reporter to the Government of India. The first Director-General of Observatories was Sir John Eliot.
  • The Headquarters of the IMD was initially Calcutta but now headquarters located in New Delhi.
  • The administrative responsibilities of the Department are under the supervision of the Ministry of Earth Sciences

What are Tropical Cyclones?

They are violent storms that originate over oceans in tropical areas and move over to the coastal areas bringing about large-scale destruction caused by violent winds, very heavy rainfall and storm surges.

  • Conditions: The conditions favourable for the formation and intensification of tropical cyclones are:
    • Large sea surface with temperature higher than 27° C;
    • Presence of the Coriolis force enough to create a cyclonic vortex
    • Small variations in the vertical wind speed;
    • A pre-existing weak low-pressure area or low-level-cyclonic circulation is must for cyclone formation in tropics
    • Upper divergence above the sea level system.

Vulnerability of India to Cyclone:

  • Indian sub-continent is the worst affected region of the world, having a coast line of 7516 kms. (5400 kms along the mainland, 132 kms in Lakshadweep and 1900 kms in Andaman and Nicobar Islands) is exposed to nearly 10% of the world’s Tropical Cyclones.
  • 40% of the total population lives within 100 km of coastline.
  • Four States (Andhra Pradesh, Odisha, Tamil Nadu, and West Bengal) and one UT (Pondicherry) on the East Coast and One State (Gujarat) on the West Coast are more vulnerable to cyclone disasters

Benefits of Tropical Cyclones:

Although Tropical cyclones are known for the destruction they cause, when they strike, they also bestow certain benefits to the climatic conditions of that area such as

  • Relieve drought conditions: By bringing rain to the coastal areas, cyclones relieve the drought like conditions in the surrounding areas.
  • Maintain equilibrium in the Earth’s troposphere: They Carry heat and energy away from the tropics towards temperate latitudes, thus helps in maintaining equilibrium of the troposphere.
  • Cyclones help in maintaining a relatively stable and warm temperature worldwide.

Causes of destruction caused by Cyclones:

There are three elements associated with cyclones that cause destruction during its occurrence. These are:

  • Strong Gusts/Squall:
    • These are very strong winds that accompany a cyclonic storm damages installation, dwellings, communications systems, trees, resulting in loss of life and property.
  • Gusts: These are short but rapid bursts in wind speed. These are the main cause of damage. Gusts are generally short-lived.
  • Squalls: A squall is a strong rise in wind speed which generally lasts for some time. Squalls generally associated with the bands of thunderstorms.
  • 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 is a serious problem for the people which become shelter less due to cyclone.
    • Heavy rainfall from a cyclone is usually spread over wide area and cause large scale soil erosion and weakening of embankments.
  • Storm Surge: It can be defined as an abnormal rise of sea level near the coast caused by a severe tropical cyclone;
    • Seawater inundates low-lying areas of coastal regions drowning human beings and life stock, causes eroding beaches and embankments, destroys vegetation, and leads to a reduction of soil fertility.
  • Apart from these Cyclones also create destructions such as
    • Sudden Change in Regional climate: The ability of cyclone to bring in warmer air is high. So, the elderly and children in those areas have a high vulnerability to develop heat-related problems such as heat strokes.
    • Loss of Livelihood: The majority of the coastal people generally depend on fishing which is completely halted by cyclones.
    • Loss of economy: The economic loss is in multifront from infrastructure loss, relief packages to people, etc.

Challenges in Cyclones Management:

  • Bare minimum Technology: At the terminal-end generally lacks the equipment and communication back-up to deal with the situation effectively.
  • Lack of grass root level participation: There is a wider awareness gap is there between disaster management from people’s end.
  • Multiple agencies: The IMD issues meteorological or weather forecasts while the Central Water Commission (CWC) issues flood forecasts at various river points. But cyclones bring the combination of problems. Before the integration of data people on the ground lost the “golden time”.
  • Low data: The government has not measured the peak flows in the rivers and canals to plan remedies and also not documented data on annual flooding patterns.
  • Absence of land use norms has spawned an amorphous housing sector characterized by inflated, speculative prices but no foundation of civic infrastructure.
  • Poor Urban planning: Many Indian cities lacks poor urban planning which is highlighted by floods in Chennai and Mumbai.
  • Climate Change: There are many proven records that exist between the link between the higher frequency of disaster and climate change.

Government Initiatives:

  • Government is carrying out a National Cyclone Risk Mitigation Project (NCRMP) with the help of the World Bank for upgrade cyclone forecasting, tracking and warning systems in India
  • Government is also implementing Integrated Coastal Zone Management Project (ICZMP) to improve national capacity for the implementation of comprehensive coastal management in India.
  • Government also separated Structural(includes construction) and non-structural measures for effective disaster management of cyclones
  • Solutions:
  • The government should consider the NDMA Guidelines for the management of cyclones:
  • Ensemble Warning System(EWS): Establish EWS involving observations, predictions, warnings, and customized local level advice for decision-makers (national, state, district level) to manage the impact of the cyclone (Read more about EWS)
  • Commissioning of Aircraft Probing of Cyclone (APC): Guidelines calls for the combination of manned and Unmanned Aerial Vehicles (UAV) for critical observational data gaps.
  • Cyclone Disaster Management Information System (CDMIS): Establishing a comprehensive department for coverage of all management information and provide online services to the departments of Disaster management.
  • Specifying the roles and responsibilities in institutionalizing Cyclone risk mitigation with Developmental planning.
  • Community Based Disaster Management (CBDM): Guidelines asked to launch such activities in all villages of the 84 districts vulnerable to cyclones.

Way forward:

  • With the adverse Climate Change risks posted by IPCC reports the only option for India is to better preparedness for the disaster with better urban planning, community awareness, etc.
Posted in 7 PMTagged , ,

Typhoon Goni: Asia’s most powerful tropical storm of 2020?

Read More

News: Typhoon Goni has made landfall in the eastern Philippines.

Facts:

  • Typhoon Goni: It is a tropical cyclone that recently made landfall as an extremely powerful Category 5–equivalent super typhoon in the Philippines.

Additional Facts:

  • Tropical Cyclone: They are violent storms that originate over oceans in tropical areas and move over to the coastal areas bringing about large-scale destruction caused by violent winds, very heavy rainfall, and storm surges.
  • Wind Direction: The winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
  • Different Names: Tropical Cyclones are known by different names in different regions:
    • Cyclones in the Indian Ocean
    • Hurricanes in Atlantic
    • Typhoons in the Western Pacific in the South China Sea
    • Willy-Willies in Western Australia.
  • Conditions: The conditions favorable for the formation and intensification of tropical cyclones are:
    • Large sea surface with a 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 and
    • Upper divergence above the sea level system.
Posted in PUBLICTagged ,

Super Cyclone Amphan Is Set to Hit India and Bangladesh

Read More

Source: Click here

News: Cyclone Amphan has intensified into a super cyclonic storm and is expected to make landfall between West Bengal and Bangladesh close to Sundarbans.

Facts:

Cyclone Amphan:

  • Cyclone Amphan is a tropical cyclone formed over Bay of Bengal that has turned into a super cyclonic storm.
  • The Cyclone Amphan is also the strongest storm to have formed in the Bay of Bengal since the super cyclone of 1999 that ravaged Paradip in Odisha.

Why does the Bay of Bengal receive higher Cyclones compared to Arabian Sea?

  • Higher Rainfall: Bay of Bengal receives higher rainfall which provides required humidity for cyclone formation.
  • Location: The typhoons originating in the Pacific Ocean too influence the cyclones in BOB not the case in Arabian Sea.
  • Constant Inflow of Fresh Water: The inflow from the Ganga and Brahmaputra rivers makes it impossible for the warm water to mix with the cooler water making it ideal for a cyclonic depression.
  • Sluggish Winds: It keeps temperatures relatively high of about 28 degrees around the year.

Reasons responsible for intensification of Cyclones in Bay of Bengal:

  • In 2020, the Bay of Bengal has observed record summer temperatures due to global warming from fossil fuel emissions that have been heating up oceans.
  • However, such unusual warming around India is no longer restricted to just the BoB but also the Arabian Sea and the Indian Ocean.It makes storm prediction less reliable as well as disrupting monsoon patterns.
  • Further, reduced particulate matter emissions during the lockdown resulted in fewer aerosols such as black carbon that are known to reflect sunlight and heat away from the surface.

Classification of Cyclones: The criteria followed by Indian meteorological Department(IMD) to classify Cyclones in the Bay of Bengal and in the Arabian Sea are as under:

            Types of DisturbancesAssociated Wind Speed in the Circulation
              Low Pressure Area            <31 km/hr
              Depression          31-49 km/hr
              Deep Depression          50-61 km/hr
              Cyclonic Storm          62-88 km/hr (Here,IMD assigns the                                      name to Cyclone)
              Severe Cyclonic Storm          89-118 km/hr
              Very Severe Cyclonic Storm          119-221 km/hr
              Super Cyclonic Storm          >222 km/hr

Different Colour Codes:

  • Green(No warning): No advisory is issued in such cases.
  • Yellow(Be updated): It indicates severely bad weather panning across several days.It also suggests that the weather could change for the worse causing disruption in day-to-day activities.
  • Orange/ Amber(Be prepared): It is issued as a warning of extremely bad weather with the potential of disruption.It is also a sign for people to prepare for evacuation and protect themselves from bad weather.
  • Red(Take action): It is issued when the extremely bad weather conditions are certainly going to disrupt life.In this case, people must take all measures to protect their families and follow the instructions of local authorities and disaster-response teams.

Additional Facts:

  • IMD:It was established in 1875 under the Ministry of Earth Sciences.It is the principal agency responsible for meteorological observations, weather forecasting and seismology.
Posted in 9 PM Daily ArticlesTagged ,

Cyclones Titli

Read More

Context:The Regional Integrated Multi-Hazard Early Warning System (RIMES) has termed ‘Titli’, the severe cyclonic storm that devastated Odisha in October, as ‘rarest cyclone’.

Note: In October 2018, Severe Cyclonic Storm Gaza had hit coastal areas of Tamil Nadu

RIMES

  • The RIMES is an intergovernmental body registered under United Nations.
  • It is owned and managed by 45 collaborating countries in Asia Pacific and Africa Region.
  • It seeks to establish regional early warning system within multi-hazard framework for generation and communication of early warning information and capacity building for preparedness and response to trans-boundary hazards.
  • It provides information related to Tsunami and extreme weather conditions. It also acts as a test bed for emerging technologies and help to enhance performance

Cyclones in India:

Cyclones mainly occur during post monsoon and less in pre-monsoon and monsoon season. Cyclones affect both the Bay of Bengal and the Arabian Sea; however, the Bay of Bengal witness more cyclones than the Arabian Sea. This is because:

  1. Bay of Bengal has higher ocean surface temperature than the Arabian Sea. This helps in formation and intensification of cyclonic storms
  2. High rainfall and inflow of freshwater:
  • The Bay receives higher rainfall and a constant inflow of freshwater. Therefore, its surface water keeps getting refreshed, making it impossible for the warm water to mix with the cooler water below, making it ideal for depression.
  • On the other hand, enhanced vertical mixing in the Arabian Sea limits cyclone intensification.
  1. Role of remnants:
  • Cyclones that form over the Bay of Bengal are either those develop insitu over southeast Bay of Bengal and adjoining Andaman Sea or remnants of typhoons over Northwest Pacific and move across south China sea to Indian Seas. As the frequency of typhoons over Northwest Pacific is quite high, the Bay of Bengal also gets higher number of cyclones.
  • On the other hand, the cyclones over the Arabian Sea either originate insitu over southeast Arabian Sea or remnants of cyclones from the Bay of Bengal that move across south peninsula. As the majority of Cyclones over the Bay of Bengal weaken over land after landfall, the frequency of migration into Arabian Sea is low.

What makes Cyclone Titli unique?

Cyclone Titli

Both India Meteorological Department and the RIMES designated as “rarest cyclone” because of its following unique characteristics:

  • North-eastward recurvature (change in direction) over the land: The normal behaviour of the cyclones forming in the Indian seas is that after deriving strength from the moisture in waters such as the Bay of Bengal, they move west, incline in a northerly direction and move out into the sea or land, depending on their origin. However, cyclone Titli recurved in a north-easterly direction over the land. It had made a recurvature away from coastal areas for more than 2 days
  • Retaining its destructive potential after landfall: After landfall, a cyclone loses speed and intensity as it loses the source of energy from warm ocean waters and gradually dissipates. However, cyclone Titli, recurved its path and gained intensity.

Note: Recurving occurs due to air currents in the local atmosphere that push cold air from the poles towards the equator and interfere with cyclone formation. 

How are Cyclones named?

    • In the beginning, storms were named arbitrarily.
    • The tradition of naming cyclones started with hurricanes in the Atlantic Ocean, where tropical storms that reach sustained wind speeds of 39 miles per hour were given names
    • In 1953, the US weather service officially adopted the idea and created a new phonetic alphabet (international) of women’s names from A to W, leaving out Q, U, X, Y and Z.
    • Male names were included in 1978.
    • The process of naming cyclones involves several countries in the region and is done under the aegis of the World Meteorological Organization.
    • For the Indian Ocean region, deliberations for naming cyclones began in 2000. A formula was adopted in 2004

How has naming a cyclone helped?

  • It helps in the quick identification of storms in warning messages
  • Names are presumed to be far easier to remember than numbers and technical terms.
  • Giving names to storms makes it easier for the media to report on tropical cyclones, heightens interest in warnings and increases community preparedness

Impact of Cyclone Titli:

The Odisha government, with support from the World Bank National Cyclone Risk Mitigation project, increased disaster preparations including building shelters, evacuation planning, conducting drills and strengthening embankments. It had initiated Mission zero causality for all disasters. However, its Cyclone risk management has been primarily focussed on coastal areas. The unique nature of Titli-its recurvature and retention of intensity even after landfall had posed serious challenge and led to death and destruction in non-coastal areas.

Disaster Management of Cyclone in India

  1.      Pre-Disaster

Structural Measures:

Structural measures include construction of cyclone shelters, construction of cyclone resistant buildings, road links, culverts, bridges, canals, drains, saline embankments, surface water tanks, communication and power transmission networks etc.

Non-Structural Measures:

Non-structural measures include early warning dissemination systems, management of coastal zones, awareness generation and disaster risk management and capacity building of all the stakeholders involved.

  1.      During Disaster: Immediate rescue operations, supply of water, medicines, food and other necessary items, Damage assessments
  2.      Post Disaster: Rehabilitation, Providing financial assistances, arrangements of relief measures.

Government Initiatives

National Cyclone Risk Mitigation Project (NCRMP)

Aim: The scheme aims to:

  • upgrade cyclone forecasting, tracking and warning systems,
  • build capacity in multi-hazard risk management
  • Construct major infrastructures including multi-purpose cyclone shelters and embankments.

Principal Components: The major components under the scheme are:

  1.  Community mobilisation and training
  2.  Cyclone Risk Mitigation Infrastructure (construction of cyclone shelters, roads/missing links and construction/repair of Saline Embankments etc.)
  3.  Technical assistance for capacity building on Disaster Risk Management (risk assessment, damage and need assessment)
  4. Capacity Building and knowledge creation along with project management and implementation support

Integrated Coastal Zone Management Project (ICZMP)

  • It is a World Bank assisted project which aims at national capacity development for implementation of comprehensive coastal management in India. Broad objectives of the project include:
  • Cyclone forecasting
  • Tracking and warning systems
  • Cyclone Risk Mitigation and Capacity Building
  • Major infrastructure to be constructed under multipurpose cyclone shelters, access roads, underground cabling and saline embankments
  • Disaster Mitigation
  • Lowering loss of lives, property in vulnerable states

NDMA Guidelines:

  1. Establishment of exclusive eco-system monitoring network to study the impact of climate change
  2. Adoption of Aircraft Probing of Cyclone (APC) facility to fill the critical observational data gaps and significantly reduce the margin of error in predicting cyclone track, intensity and landfall
  3. Establishment of a comprehensive Cyclone Disaster Management Information System (CDMIS)
  4. Establishment of a state-of-the-art cyclone early warning system (EWS) involving observations, predictions, warnings and user friendly advisories
  5. Structural mitigation should be taken up which include- improvement in structural lifeline infrastructure, construction of multi-purpose cyclone shelters and cattle mounds, ensuring cyclone resistant design standards in rural and urban housing schemes, building all-weather road links, bridges, culverts and saline embankment
  6. Management of coastal zones should include mapping and delineation of coastal wetlands, patches of mangroves and shelterbelts and identification of potential zones for expanding bio-shield spread based on remote sensing tools.

Way Ahead

  1. The Early Warning System for cyclones should be strengthened to ensure timely and accurate information about cyclone- its track, intensity, time of landfall and likely impacts.
  2. A rare cyclone like Titli highlighted the lack of impact-based actionable early warning information and prior experience in addressing such disasters. Therefore, research and detailed assessment is necessary combat such disasters in future.
  3. It is important to ensure timely dissemination of warning. IMD’s cyclone alerts should be disseminated by broadcasters to all levels of governance and public
  4. The disaster management authorities should be more proactive in search and rescue operation after a cyclone disaster so that the loss of life can be negated.
  5. There should be proper coordination between the Centre, State and several Government agencies, and trained personnel for prompt and organised response after a cyclone.
  6. Structural measures such as designing and building of robust cyclone proof shelters, ensuring availability of essential infrastructure is important.
  7. Rapid urbanization and increasing encroachment in coastal areas is a major problem. Coastal Regulation zone norms should be strictly enforced.
  8. Awareness generation among all stakeholders is important for cyclone risk mitigation.
  9. Odisha State Disaster Management Authority should learn lessons from Cyclone Titli to evolve measures to minimise impacts in both coastal and non-coastal regions more effectively in future
Posted in Featured EditorialsTagged

Explained: Why cyclones hit the east coast in October, and how they are predicted

Read More

Explained: Why cyclones hit the east coast in October, and how they are predicted

News:

  1. The article talks about the hurdles the scientists face in accurately predicting the cyclones along with conditions in Bay of Bengal.

Important Facts:

2. Recently cyclone Titli became the third major cyclone to hit the Odisha-Andhra coastal zone in the last five years, all in October.

3. Cyclone Titli struck in same month as Phailin and Hudhud, but still the forecasting department failed to notice its arrival.

4. Reasons for poor forecasting:

  • Poor data gathering technique: India have to rely on satellite images that reveals little data on moisture content and intensity to predict the developing cyclones over Indian ocean were as US has dedicated aircraft in the Atlantic basin, which fly directly into the clouds to study moisture levels and gather various data on cyclone profile.

Indian scientists get a more detailed picture only when a cyclone is 300-400 km from the coast, which reduces preparation time.

  • Lack of budgetary support: India acquires storm prediction models from the US and Europe but lacks the resources to upgrade the models regularly.
  • Cyclone Titli was additionally hard to read because it turned into a recurving cyclone (it changed direction.
  1. Season and frequency of cyclones in Bay of Bengal:
  • The Bay of Bengal receives the remnants of major landfalls in the Philippines, China and South Asia.
  • From these places come low-pressure systems that develop into a monsoon depression or a cyclone in Bay of Bengal.
  • This is because it is adjacent to the northwest Pacific, which is one of the world’s most active basins for typhoons.
  • The cyclones such as Titli, Phailin (2013) and Hudhud (2014) typically strike in October because of wind shear.
  • Low wind shear, when combined with surface sea temperatures greater than 26°C, raises the likelihood of cyclones.

  1. Evacuation during cyclones:
  • Researchers classify evacuation exercises as preventive, vertical, and shelter-in-place.
  • Preventive (or horizontal) evacuation: The impact area is completely evacuated, but this is a measure rarely taken in India because of poor roads and inadequate public transportation. Also, poor people rarely have the resources to find alternative accommodation.
  • Vertical evacuation: Here people are directed to specially designed buildings within the impact area. This strategy was largely followed during Cyclone Titli.
  • Shelter-in-place evacuation: It involves fortification of existing houses and community buildings, which require financial resources.
  1. Storm surge and saving lives:

  • During Titli, Hudhud or Phailin, lives were saved because, unlike the 1999 Super Cyclone, there was no storm surge.
Posted in Test 1Tagged