1.
CYCLONE DISASTER
MANAGEMENT
Dr Fayaz A. Malla
Assistant Professor, Environmental Sciences
GDC Pulwama
Higher Education Department, Govt. of J&K
Email: nami.fayaz@gmail.com

2.
Definition
• A cyclone is a large scale air mass that rotates around a strong
center of low atmospheric pressure.
• They are usually characterized by inward spiraling winds that
rotate clockwise and anti-clockwise.
• A tornado is rotating column of air whirling at destructively
high speeds, usually accompanied by a funnel-shaped
downward extension of a thundercloud.

3.
Geographical Location
Cyclones begin in tropical regions such as Pacific islands,
Northern Australia and other areas.
Tornadoes have been spotted in all continents except
Antarctica. Highest frequencies occur in the Netherlands,
and up to 1200 on average in the United States.

4.
Characteristics
• Cyclones have a low pressure center which is called the "eye", and the
wind circling around is counter clockwise on the northern hemisphere
and clockwise in the southern hemisphere.
• The speed of cyclones varies from 32 to 200 kmph.
• Cyclone mainly occur in a particular season and mainly affect the
coastal areas.
• Cyclones can be of three main types:
 Polar
 Tropical
 Mesocyclones
6

5.
• Tornadoes normally rotate cyclonically (when viewed from above, this is
• counterclockwise in the northern hemisphere and clockwise in the
• southern).
• The speed of tornado varies from 60 to 480 kmph.
• Tornadoes are most common in spring and least common in winter.
• Tornadoes can be of three main types:
 Multiple vortex
 Waterspout
 Landspout
Tornado

6.
Intensity and Damage
• The scale for measuring cyclones is called the Beaufort Scale
and Saffir-Simpson scale and may vary in different countries.
• The scale for measuring the intensity of cyclones depends on the
intensity of damage and the wind speed.
• The scale ranges from negligible house damage, and destruction of
plants and tress to extensive damage and widespread destruction,
with wind speed ranging from 74 to 156 mph.

7.
• The intensity of tornadoes can also vary in intensity those with a
longer track being stronger. The scale used for rating the strength of
tornadoes is called the Fujita (F), Enhanced Fujita (EF), and TORRO (T)
Scale.
• The range varies from F0, EF0 or T0 for minimal damage (damages
trees but not buildings) up to F5, EF5 or T11 for vast degree of damage
(buildings and skyscrapers end up getting damaged).
• In the United States, maximum tornadoes (80%) fall into the EF0 and
EF1 (T0 to T3) category and less than 1% are violent (EF4, T8 or more).
Tornado

8.
Detection
Cyclones and tornadoes are detected by Pulse Doppler
radar, photogrametry, and ground swirl patterns.

9.
Photos
Cyclone Tornado
Source: Cyclone Nilofar
URL: https://goo.gl/qt4wSr
Source: This was part of the Oklahoma
tornado outbreak on May 3, 1999
URL: https://goo.gl/3iUbfu

10.
Comparison

11.
PROTECTION AGAINST CYCLONE
Four Stage Warning

12.
• Extreme Weather Events
• Causes major loss of lives and live stocks.
• In single event 2 to 3 lakh people lost lives.
(Bangladesh Cyclone, November 1970.)
• Only weather system which bears name or
identification because of long life.
Eye Eye-wall
Convective cells
Spiral cloud bands
TROPICAL CYCLONE
Low pressure system
Low (<17 knot)
Depression (17-27)
Deep Depression (28-33)
Cyclone (34-47)
Severe Cyclone (48-63)
Very Severe Cyclone (64-119)
Super Cyclone (12 and above)

13.
STORM
SURGE
CYCLONE
LOCAL TIDES
LOCAL COASTAL
CONFIGURATION
WIND
RAIN
FLOODING OF COASTAL AREAS
EROSION OF BEACHES
LOSS OF SOIL FERTILITY FROM
SALINE INTRUSIONS
DAMAGE TO STRUCTURES
LOSS OF
POWER/COMMUNICATION
INJURIES & LOSS OF LIFE
DESTRUCTION OF CROPS,
VEGETATION, LIVE-STOCK
CONTAMINATION OF WATER
SUPPLY SYSTEM
LAND SUBSIDENCE
FLOODING OF INLAND AREA
Potential damages due to tropical cyclones

14.
NORTH INDIAN OCEAN
• Bay of Bengal is a vast warm pool adjoining the warm pool of the
western North Pacific. Several of the precursors of the Bay of Bengal
cyclones emerge from the neighboring Pacific basin as remnant of
typhoons and re-intensify over the Bay after passing over rather narrow
strip of SE Asian countries
• Ocean currents in the Bay of Bengal are quite complex and in the post-
monsoon season low salinity warm waters begin to cover eastern
coastal waters from October to December through the East India
Coastal Current

15.
State Total No.
West Bengal 69
Orissa 98
Andhra Pradesh 79
Tamil Nadu 62
Karnatka 02
Maharashtra & Goa 18
Gujarat 28
Kerala 03

16.
PAST STUDIES

17.
Probable Maximum Storm Surge in meters
for each coastal District
A shallower bathymetry
piles up the surge more
Source: IMD

18.
Category : Cyclonic storm T Number : T2.5
Wind speed : 34-47 Knots 62-87 Kmph
Structures : Damage to thatched huts
Communication and power: Minor damage to power and communication
lines due to breaking of tree branches.
Road/Rail : Major damage to Kutcha and minor damage to Pucca roads.
Agriculture : Some damage to paddy crops, Banana, Papaya trees and
orchards.
Marine Interests : High to very high sea waves about 6-9 m high.
Coastal Zone : Sea water inundation in low lying areas after erosion of
Kutcha embankments
Overall Damage Category : Minor to Moderate
Impact of Cyclonic Storms

19.
Category : Severe Cyclonic storm , T Number : T3.5
Wind speed : 48-63 Knots (88-117 Kmph)
Structures : Major damage to thatched houses / huts. Roof tops may blow off.
Unattached metal sheets may fly.
Communication and power: Minor damage to power and communication lines.
Road/Rail : Major damage to Kutcha and some damage to Pucca roads. Flooding
of escape routes.
Agriculture : Breaking of tree branches, uprooting of large avenue trees. Moderate
damage to Banana and Papaya trees. Large dead limbs blown from trees.
Marine Interests : Phenomenal seas with wave height 9-14 m. Movement in motor
boats unsafe.
Coastal Zone : Major damage to coastal crops. Storm surge upto 1.5m (area
specific) causing damage to embankments/ salt pans. Inundation upto 5 Km in
specific areas.
Overall Damage Category : Moderate
Impact of Cyclonic Storms

20.
Category : Very Severe Cyclonic storm , T Number : T4.0 – 4.5
Wind speed : 64-90 Knots (118-167 Kmph)
Structures : Total destruction of thatched houses/ extensive damage to Kutcha
houses. Some damage to Pucca houses. Potential threat from flying objects.
Communication and power: Bending/uprooting of power and commn poles.
Road/Rail : Major damage to Kutcha and Pucca roads. Flooding of escape
routes. Minor disruption of railways, overhead power lines and signaling
systems.
Agriculture :Widespread damage to standing crops plantations, orchards, falling
of green coconuts and tearing of palm fronds Blowing down bushy trees like
mango.
Marine Interests : Phenomenal seas with wave heights more than 14m. Visibility
severely affected. Movement in motor boats and small ships unsafe.
Coastal Zone : Storm surge up to 2 m, Inundation up to 10 Km in specific areas.
Small boats, country crafts may get detached from moorings.
Overall Damage Category : Large
Impact of Cyclonic Storms

21.
Category : Very Severe Cyclonic storm , T Number : T5.0 – 6.0
Wind speed : 91-119 Knots (168-221 Kmph)
Structures : Extensive damage to all types Kutcha houses, some damage to
old badly managed Pucca structures. Potential threat from flying objects.
Communication and power: Extensive uprooting of power and
communication poles.
Road/Rail : Disruption of rail / road link at several places.
Agriculture :Extensive damage to standing crops plantations, orchards.
Blowing down of Palm and Coconut trees. Uprooting of large bushy trees.
Marine Interests : Phenomenal seas with wave heights more than 14m.
Movement in motor boats and small ships not advisable.
Coastal Zone : Storm surge up to 2 – 5 m, Inundation may extend up to 10-
15 Km over specific areas. Large boats and ships may get torn from their
moorings, country crafts may get detached from moorings
Overall Damage Category :Extensive
Impact of Cyclonic Storms

22.
Category : Super Cyclonic storm , T Number : T 6.5 and above
Wind speed : 120 Knots and above (222 Kmph and above)
Structures :Extensive damage to non concrete residential &industrial building.
Structural damage to concrete structures. Air full of large projectiles.
Communication and power: Uprooting of power and communication poles.
Total disruption of communication and power supply.
Road/Rail : Extensive damage to Kutcha roads and some damage to poorly
repaired pucca roads. Large scale submerging of coastal roads due to flooding
and sea water inundation. Total disruption of railway and road traffic due to
major damages to bridges, signals and railway tracks. Washing away of rail / road
links at several places.
Agriculture :Total destruction of standing crops/orchards, uprooting of large
trees & blowing away of palm and coconut crowns, stripping of tree barks.
Marine Interests : Phenomenal seas with wave heights more than 14m. All
shipping activity unsafe.
Coastal Zone : Extensive damage to port installations. Storm surge more than 5m,
Inundation up to 40 Km in specific areas and extensive beach erosion. All ships
torn from their moorings. Flooding of escape routes.
Overall Damage Category :Catastrophic
Impact of Cyclonic Storms

23.
Classification of Cyclone Prone Districts
 All coastal districts are cyclone prone.
 Therefore, it become imperative to
decide degree of proneness.
 In general, coastal districts in WB,
Orissa, AP & TN are in high to very
high category.
 Some interior districts in NE
India(earlier included in BMTPC atlas)
excluded.
 Cyclone proneness is very high for the
districts of south 24 praganas &
Midnapore (West Bengal), Balasore,
Kendrapara, Bhadrak, Jagatsinghpur
& Ganjam (Orissa), Nellore, Guntur,
east Godabari (Andhra Pradesh)

24.
Cyclone Operation in India
• Meteorological Department, by providing Cyclone Surveillance Radars at
Calcuta in the east coast and at Goa, Bombay in the west coast.
• Satellite picture receiving equipments at Delhi, Bombay, Madras are
receiving satellite pictures of the cyclones from the polar-orbiting Satellites of
the U.S.A. and U.S.S.R. Since April 1982.
• A.V.H.R.R. (Advance very High Resolution Radio-meter) Indian Geo
Stationary Satellite INSAT-LB has become operational since October 1983.
• Monitoring of the cyclone by taking hourly pictures has helped the forecaster
to improve his skill in issuing the timely warnings to the public.
SOME INDIAN ASSOCITIONS
• Area Cyclone Warning Centres (ACWC)
• Cyclone Warning Centres (CWC)
• Numerical Weather Prediction (NWP)
• Northern Hemispheric Analysis Centre (NHAC)
• Cyclone Warning Research Centre (CWRC)
• Regional Specialized Meteorological Centre