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TIDAL WAVES CYCLONES STORM SURGES COASTAL EROSION AND

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           TIDAL WAVES, CYCL/ONES, STORM SURGES, COASTAL
             EROSION AND SUBMERSTON OF COASTAL AREAS

Except for the two land-locked countries of Nepal and Bhutan" all the other five SAARC nations are afflicted by
cyclones,tidal wavesand their compoundingeffects.Clclones may haveperipheral effectsevenon Nepal and Bhutan.
Becauseof their extensivecoastlines,India, Bengladesh,Pakistan,Sri I-anka and Maldives have suffered from sea
basedstorms in varying degrees.The devastating1991cyclonein lenglxdssh and the periodic storm surgesover the
easterncoastof India show the propensig and destructive     violenceof cyclonesemanatingfrom the Bay of Bengal.
Although only about sevenper cent of the global tropical cyclonesoccur in the north Indian Oceen, they are the
deadliest the world. Factorslike the shallowwatersof the Bay sf le,ngal, the low and flat coastalfslvain of India
         in
and Bangladesh,and the funnel shaped coastline combine to produce huge lossesof life and property even with
storms of moderate intensity. The Bakerganj cycloneof 1876and the cycloneof 1970each killed more than 200,000
peoplein BenglsdqFh. 191, the most powerfulcyclonein Bangladesh's
                      In                                                 historyleft more than llX),Ofi)peopledead
and large scale destruction of property, almost ruining the country's economy.

Tropical cyclones possiblythe most destructive natural phenomena their combinationof violence,duration
                  are                           of                 in
and size of arca affected. Cyclonesare low pressuresystemsaround which the air circulatesin an anti-clockwise
                                    The rotating massof warm humid air is normally between300 km and 1500
direction in the northern hemisphere.
km in diameter.The strongwind, which may approach kn/hr or more, blowsaroundthe eyeof a cyclone,
                                                   250                                                 which
can range from a few kilometresto more than 100km in diameter.

The nomenclature tropical stormsvariesfrom one region of the world to another.Tropical stormswith sustained
                    of
winds of 64 knots are called hurricanes in the Atlantic and eastern Pacific; tlphoons in the western north Pacific;
willy-willy in Australia; Baguio in the Philippine islands;and severecyclonesin South Asia. Tropical cyclonesare
seasonal  phenomenaand their greatestfrequencyis during periods of maximum seasurface temperatures,although
other  factors are also important. In the north Indian Ocean,this period is from May to June and from October to
December.About six cyclonesreach tropical storm intensity in the north Indian Ocean each year. Large variability
hasbeen reported in the location of stormsfrom decadeto decadealthoughno systematic        patternshaveemerged.

A storm surgeis a shoal-water   process generated tropical cyclones. is definedas a superelevation sealevel
                                                   by                    It                              of
due to a combination of wind-driven water and an uplift induced by the pressure drop. The sea level can rise to
immenseheightsas a tropicd cyclonecentrearrivesat the shore.As the centreof the cycloneapproaches shore,  the
sea levels rise and inundation begins, which is increasedby freshwater runoff from heavyrains in river and stream
basins.Together, all these constitute what is knoum as the hurricane tide (cyclone tide or a tidal wave). A cyclone
that moves rapidly towards its landfall will ordinarily ceate a larger peak surge than if it approachesslowly.

Pre-monsoon,monsoon and post-monsoonperiods are the three seasons       when cyclonesand depressionsform in the
Bay of Bengal, Cyclones,    which form during pre-monsoonand post-monsoonperiods, are the most destructivedue
to the great instability of the atmosphereand the weak vertical winds. They generally form over the Andaman Sea
or southeastBay of Bengal.They initially move west,/northwestwards,  then northwards, and finally in a northeasterly
direction,and crossSengladesh the upper Burma coast.Someof them also crossthe tndian coastin Tamil Nadu,
                                  or
Andhra Prades\ Orissa and West Bengal. The cyclonic storms which form during the southwestmonsoon are not
so destructivedue to the presenceof large vertical winds.


Efrects of cycfones

When a cycloneor depressionapproaches country, a risk of seriousloss or damagearisesfrom severewinds, heavy
                                            a
rainfall, storm surgesand river floods. The force exertedby the wind is proportional to the square of its speed.The
total damagedue to wind may, therefore, be expectedto increaserapidly with the more violent cyclones.There is
a threshold speedlevel below which damagecausedby wind is tairly snall and abovewhich it is considerable.In case
of agriculture, the threshold speed is relatively low; an4 for buildings, it dependson the type of construction and
structural material used. The effects of a storm surge are most pronounced in wide and shallow bays exposedto
cyclones   suchas in the northern part of the Bay of Bengal.Someof the world's greatesthuman disasters     havebeen
attributed to storm surgeswhich occurred severalhours in advanceof a cyclone'slandfall, bringing floods at a time
when the evacuationof people was still in progress.


                                                       165
Sengladeshhas the worst record of cyclonesand tidal surges.Clclones and tidal surgesare fnequentin the months
of October and November.These disastersdestroy crops, de-age infrastructure, housesand vital installations, and
causewidespreadhealth hazardsfor the people.They occur so frequently and in such magnilude in Bangladeshthat
they havemultiplied the problems of poverty and seriouslychallengedthe efforts of the country towards self-reliance.

The major natural disastersthat affect the coastalregionsoflndia are cyclones,storm surgesand coastalerosion due
to waves.India has a coastlineof about 9,m0 km of which 55 per cent are beachesand 25 per cent shores,including
deltas.The rest include rocky overhanFng cliffs or combinationsof rocky and beach shores.

Clclonic storms and storm surgesare nuch more common on the east coast of India than on the west coast. The
India Meteorological Department has been collecting data on cyclonic storms for well over a century now. The
nu-ber of cyclonic storms that have formed in the Bay of Bengal and the Arabian Sea in different months during
the period 1891-1970 given in table 14.1.Most of the severestorms which originate in the Bay of Bengal strike
                     are
the coast. The incidence of cyclonic storms (with wind speedsbetween34 knots and 63 knots) and severecyclonic
storms (with wind speedsbetween64 knots and 89 knots) reachingTanil Nadu and Andhra Pradeshis high during
the post-monsoonseason(October-December),whereasfor the Orissa-WestBengal coastthe number is high during
mons(x)n and summer seasons,    respectively.The Orissa-WestBengal coast has 1f,Ehighssl ar€rage annual nunber
of storms, severestorms, and consequentlystorm surges.Damagesdue to storm surgesin the Bay of Bengal region
durtng the 30 year period 1945-75  have been estimated at US $ 7 billion.

In Sri Lanka, devastatingcyclonesare rare. Major storms usually affect sparselypopulated coastal areas of the east
and northwest parts. Coral and sandstone  reefs that parallel most of Sri l-anka's shoreline act as natural breahraters.
The cyclone seasonof Sri l-anka is from November to December as 83 per cent of cycloneoocrurenceqwhich have
reached its east coast, have been during this period. A freak cyclone forming off the west coast moved across the
island to the east in October L967.The total number of cyclonic storms lsxshing the east coast of Sri I-anka during
the period 1881-1980 shown in table 14.2.Out of the 12 cyclonic storms, four have been severe.These occurred
                       is
in 1907,Ly22,l9g and 198. The most devastating     cycloneto hit Sri Lanka was that of November 1978,which moved
in from the Bay of Bengal. A million people were affected in that cyclone.About 100,000people were rendered
homelessand 915 lives were lost. At Kalkudalr" the sea entered inland to a distance of about 1.5 km. About 50 pet
cent of the roofs of buildings along the path were bloum off. Coconut plantations in the area were wiped out.

In Maldives, long distanceswellsand hiefi water levelsdue to wavesurgesand higb tides would not havecausedmuch
damagewere it not for the mismanagement        that has taken place in developmentalactivities. This mismanagement
includes stripping the islands of their natural defencesprovided by the outer reefg reef flats and beaches.

Maldives has a unique situation. It has a large number of small islandswith an average height of 0.8 m to 2 m above
sea  level. The islandsare exposedto continuousattack of wavesand currents. But as theseislandshave been formed
at the rim of atolls, a natural defence is being provided by coral reefs. The reefs face the ocean waves first and
dampen their effect before they reach the islands.Hence, they act as a natural breakwater for the islands.But as the
continuous attack of oceatrwavesdamagesthe corals, their smothering death and decayover the years producesa
large quantity of coral sand which moves towards the islands and enrichesthe beaches.The sandybeachesfurther
danpen the fury of the wavesand give protection to the islands.Thus, the protection of coral reefs is very crucial
for the survival of these islands. The damage causedto the reefs due to exploitation of corals has disturbed the
delicatebalanceof this natural defenceand at times cilusreserosion on someislands.Any further damageto the reefs
will destroy this natural protection againstoceanwavesand tides and lead to disaster.

The weather in the country is dominated by the southwestmonsoon from April to November and the northeast
monsoonfrom December to March. However,Maldives is not subjectto cyclones.    Winds are seldom over 8.5-14m/s.
Gale and storm force winds are rare and cyclonesare unknown. The windiest time is June and July when tropical
storms and gales are most frequent in the Arabian Seato the north of the Maldives. Similarly, in late October and
November, tropical storms may track westwardjust to the north of Maldives from the Bay of Bengal at the end of
the southwestmonsoon period.

No serious studies on wave direction has been made in Maldives. Wind generated waves and oceanic swells are
conditioned by monsoon wind directions, and their effect is more noticed in the atolls of southern and central
southern Maldives.Wavesgeneratedby the southwestmonsoonin the Indian Ocean north of the equator are2-3 m
high. The effect of thesewavesis, howerrer, reduceddue to waverefraction and interference by thc atoll configuration
and the natural defenceprovided by the wide fringing reefs. Howewr, deepwaterswells are knocm in the Male atoll
causingproblems for ships and bargas.The floods of the south Male reclained area, Hulule aitpott, other islands
northeast of Male, and in the atolls of the south, are attributed to long swells generated in the Indien Ocean,west
of Australia. Coastal flooding in Maldircs due to high tides has been e:pericnced at various places.The impact of
recent flooding has been more noticeable becauseof the construction of walls and housesnear the shore and on
lowlyingreclaimedland and in areasdamaged humans.
                                         by

Cyclonesand storm surgesalong Pakistan's112I)kn long coastlineare not so disastrousas the country is not located
in the region of cyclonicstorms.Tidal wavesand coastalerosionare, however, commonfeature.On November27,
                                                                          a
7{A5, a major earthquake of 8.3 on the Richter scale occurred along the Makran coast of Pakistan, which was
accompanied a tidal wave 12 m high with a speedof 224kra per hour. Ports along the Malran coastwere affected
              by
severelyand many fishing villagesin Sindh and Baluchistanwere washedaway.Many mud volcanoesalso sometimes
causeseveretidal waves.There is, however,no information or data available on the frequency, seasonand time of
occurrence other tidal wavesin Pakistan.
            of                             There has beensomelossof life and property due to this calamitybut
the total loss has neverbeen estimated. The expenditure relief and rehabilitationhas also been minor.
                                                        on


Coastal erosion

Coastalerosionis anotherseriousproblemthat affectsseveral     countriesof SouthAsia. The southwest   coastof India,
along the state of Kerala, is well knovm for marine erosion.This coastis eroding at the rate of six metres ennually.
Maps of 1850and 1966show that the major part of the Kerala coast has recededduring this time. About 320 km of
Kerala's 565 km coastline has been affected by erosion. In 1!b,6,ganite walls were constructed along 64 krn of the
affected coast,whEre erosion threatenedrailway lines, national highwaysand agricultural land. By 190, about 2f7
km of the coastwasprotectedby granitewalls.But waves     during the southwest monsoonharc damaged      about 70 km
of the walls and havehad to be repaired.Someerosionhasalsobeenobserved        alongtle west coastin Maharashtra.

Along the easterncoastof India, the spit calledGodavariPoint,which encloses  KakinadaBay, hasgrown northward
by about L2 km in 100 years. This is attributed to sediment dischargedue to floods and deforestation.The
sedimentationrate at Madras,Visakhapatnam GodavariPoint is estimated be L million tonnesper year.This
                                              and                             to
progradationof the shorelineis probablyof the order of 10 m, 15 m, 15 m and 5 m per annumin the Ganga/Ganges,
Mahanadi, Krishn4 Godavari and Cauvery deltas, respectively.On the western coast, the Gulf of Cambay is also
growing'

Coastalerosionwas not viewedas a major problem in Sri Lanka until the early part of this century.Today coastal
erosion is an acute problem, disrupting fishing navigation"recreation and many other coast-basedactivities.
Nonetheless, problem of coastalerosionin Sri l-anka is not unusualin terms of world trends.
            the

The major sourceof beachsandin Sri tanka is sedimentcarried doumby the rivers. Other sourcesare sediments
from eroding coastalfeatures,and offshore sandsbrought onshore.If the sandsupplied to a particular coastalsector
is less than what is carried away,the shoreline will erode. A variety of human activities contribute to the problem,
namsly, s1d 6ining from river beds and beaches,       6e1nlnining and destructionof reefs, improper location or
construction of maritime structures (for example,shoreline protection works, fishery harbours, river outfall training
schemes,   vertical or steeply-facedseawallsin close proximity to the beach),and improper removal of coastal
vegetation.

Erosion hazard is greatestduring the monsoons.The southwestmonsoonfrom May-Septembergenerateswavesof
high intensity. During this nonsooq the greatestenergyis deliveredto the areasbetweenKdpittya and Potuvil. The
northeast monsoonfrom November-March delivers somewhatlessenerg5r the Sri l-anka shore and its effects are
                                                                           to
mainly felt along the north coastand on the eastcoastas far as Potuvil. Continuing land loss is evident in someparts.
Old mapsand surveyplans of landed properties in Seenigama     area indicatesthat a large extent of land has been lost
to the sea.The small island on which the Seenigama   now standsformed part of the meinlandsomeyearsago.

Although the beachesare recedingin most parts of the islan4 the impact of coastalerosion is most severealong the
westernand southwesterncoasts.While there are isolated problems elsewhere,it is only along this segmentthat the
problem is widespread.This is also the most densely populated coastal region and development along it is most
intense.About 75 pr cent of the bigger hotels in Sri L,ankaare located in coastal areas,very near the waterline.
Coast protection schemeshave been implemented to protect the most vulnerable hotels. However, severalsmaller
structuressuchas restaurantsand swimning pools havebeen damagedor destroyed.Severalhotels have experienced
decreased  clientele becauseof non-availability of beach in the hotel frontage. Both the higbway and railway lines of
Sri l,anka rue on or near the coast. The main railway link betweenColombo and Matara runs neiu the coast along
most of its length. In the area betweenColombo and Panadurait runs very close to the beach, and most of it exists
today only due to heavy coast protection works that have been carried out during the past several years to protect
the railway line. Similarly, the main highwaylinking Colombo to the major southern towns, runs in close proximity
to the beach in most areas.Coast.protectionschemes        have been implementedin many critical areas to provide
protectionto the road. It hasbeenestimated   that alonglhe coastalsegment    extending km from Kalpitiya to Yala
                                                                                       685
National Park, about 175,000 285,000 m of coastallland lost annuallythrough erosion.Of this amount,about
                                to       sq                   is

                                                        L67
145,m0sq m are lost annuallyfrom the mouth of the Kelani River to Talawila (Kalpitiya psniisul6).

Very little work has been done in Pakistan to assess extent of marine erosion. Techniques applied so far to
                                                        the
mitigate its impact are confined to the construction of seawalls and stone pitching at certain places.The 1120km
long coastlin€of Pakistan is sparselypopulated and underutilised.The two major ports at Karachi and Qasin are
located on the Western coast of the country. A programmefor the developmentof seasiderecreational facilities has
been preparedrecently.

In the coastalregions 6f lengl2ds5b the natural processes erosion and accretionare going on due to inland fresh
                                                           of
water flows, tides, tidal sluges, and high winds. To protect the coastal land from erosion" mangrove plantation
                                                       As
programmeshave been taken up by the government. a result, more and more newly accretedlands are being
brought under manglove plantations.The mangroveafforestationproject also aims at creating a forest belt along the
coast and offshore islands to minimise loss of life and property causedby severecyclonesand storm surges.


Disaster manrgermentand fuecasting

The effective prediction of cyclonesis very important for Bangladesh.
                                                                    The intensity and developmentof a cyclone
dependon many meteorological     parameters.  Theseparameters derivedfrom meteorological
                                                               are                           observations. The
knowledge of these leads a forecaster to issue an effective forecast of a cyclonic storm, about its intensity,
developmentand future movement.Tracking of a cycloneis also done with the help of radar and satellite imageries.
When a disturbance forms in the Bay of Bengal, bulletins and warnings are issued about the origrn" path of
movement,intensityand future position.Thesebulletinsare issuedin addition to routine forecastsand warnings.

There is a standing order for dealing with emergencysituations causedby cyclonesso that necessarypreparations
can be taken up in advance.The order spells out specific functions and responsibilities of different government
minisldsg divisions, agenciesand divisional commissioners,deputy commissioners,chairmen of upazilla and union
parishads,Bangladesh   Red CrescentSocieties  and the generalpublic.

The Ministry of Relief is mainly responsiblefor disastermanagementwith the help of other departments.There is
a cyclone preparednessprogramme sincs 7972 to help the government during cyclones. There are volunteer
organisationsat grassroot level along the coastal belt of the country. They have ?nsl0 volunteers spread over 24
upazillasof eight districts (Co:CsBazar, Chittagong Feni"Noakhali"Bhola, Lu:mipur, Patuakhali and Borguna). The
upazillas are connected with the headqqrters at Dhaka by a wireless network. The volunteers are trained and
equippedwith warning equipment like transistor radios, megaphones,     sirens and signal lights. Two or three villages
constitute a unit and each unit has ten volunteers to reacb, help, rescue,render first aid and distribute relief to the
affected people.When evacuationis necessary, volunteersextensively
                                                the                       announcethe message the villagers.The
                                                                                                  to
local administration arrangesvehicleslike country boats,motor launchesand e"etre boats to evacuatepeople to safer
places.

During 1972to 195, the Bangladeshgovernmentconstructed238 cyclone sheltersunder IDA credit. Each shelter
can accommodate800 people. Since 1985,6e f,engladeshRed CrescentSocietyhas constructed60 cycloneshelters
which can accommodateover 49 people each. For cattle heads, 157 earthen killas (earthen mounds) have been
constructedunder the food for work programme.About 600cattle headscan take shelter in eachkilla. Theseshelters
are, however,not adequatein comparisonwith the total requirement.
In India" the responsibility for monitoring the weather s)4stem entrusted to the tndia Meteorological Department
                                                              is
QMD). For weather forecasting the department usesits own network of obsenatories and data from international
agencies and satellites.The departmentalso operatesa network of cyclonewarning centresto keep track of cyclonic
storms. The responsibility for monitoring and issuing cyclonewarnings has been given to these centres. Results of
mathematical models are used to issueyx;nings once a cycloneis detected.

Most of the coastalstatesof India havepreparedplans to mitigate loss of life and property, which are put into action
once a warning is issued.Typically, a state's cyclone mitigation plan at the district level is implementedby a
permanent 'cyclone committee' with the district collector as its chairman. The members qf this committee include
nomineesof stateand central governmentdepartments,one or more membersof the state legislature and parliament,
and a representativeof voluntary organisations.

The storm warning centres first issuewarningsto district collectors and to other government offrceslike the public
works departments, irrigation departments and authoritis5dealingwith railwap, ports, fisheriesetc. At the second
stage,warning messages broadcastby the All India Radio and even telecast.In addition, specificinstructions
                         are
issued the district collectorsregardingevacuation distress
      by                                          and           mitigationmeasures alsobroadcast All India
                                                                                    are               by
Radio and carried on the public wirelessnetwork.
The frequencyof storm surgeshave increasedin the Maldives during the last decaderesulting in loss of more than
40 million US Dollars worth of property in 1987and danages of more than ,1000 housesin 191. The responsibilities
for disaster management and mitigation has been given to the National Commission for the Protection of
Environment with its Secretariat1o15slt',finistryof Planningand Environment. The Commissionhas membersfrom
a large cross-section the Ministries and other Departments.
                     of

The Meteorological Department of Pakistan issues forecasts about the occurrence of cyclonic storms. When
information about an expectedstorm is received the residentsof the area are askedto vacatetheir houses.This has
happenedonly once in the last 50 years,when the residentsof Karachi living near the coastwere told to shift to other
parts, becauseof a cyclonic storm. The area was evacuatedwith the help of the local administration and the defence
forces.

Most of the housesbuilt in rural and urban areascan withstand the storms that occur in Pakistan.In urban centres,
buildi"g designshave to conform to building regulations.In rural areas,however,people build their housesmostly
with local building materials, which are often affected by storms or during a heavydownpour. There are 3 1nm!61
of rules ald regulations about the use of the sea and the coastal areas but no act or ordinance encompasses     all
aspects.There is need for a coastalzone managementact and a necessary      institutional framework to ensureproper
and safe use of the coastline.


Permanent submersion

In Maldives,no permanentsubmersion land hasbeenreported.The floodingof certainareasin the past hasbeen
                                       of
of a temporarynature. But the Maldivesdoesfeel extremelythreatenedby the projectedsealevel risesdue to the
expectedglobal warming. The Presidentof Maldives has raised the problem at various 6se,tings of the United
Nations, the Commonwealthand SAARC. As a result, a number of studieshave been made in the last three years.
He had called the small states conferenceon sea level rise in November 1989.The Male' declaration on global
warming and sealevel rise issuedby this conferenceclearly highlighted the dangersfaced by lowlying countries. In
the context of global warming it hasbeenpredicted that tropical stormswill becomemore frequent and more intense
with increased  oceantemperatures:  Hence,the northernmost   atolls of Maldivesare likely to be more affectedby the
passage thesestorms and experienpe
        of                            increasedwind and rainfall. This aspectis being coveredin a parallel detailed
study on the'GreenhouseEffect and lts Impact on the SouthAsian Region".

Evidence of land subsidencealong India's coastsis substantial.This includes presenseof peat beds, 6-13 m below
the surface, at severallocations near Calcutta and submergedforests in Valimukkam Bay near Tirunelveli and off
Bombay. l,ocal depressions  occurred during the earthquakeof 1819in Kutch and this lead to a submergence 500
                                                                                                         of
sq km of coastalland. Most of thesestudies,however,are much too localisedto know the various geological factors
controlling this phenomenon.

Tide gaugedata is useil to determine the trend of submergenoe emergencealong the coast. One such analysis
                                                                or
concludedthat Mangalore, during 195TL976,    showeda drop of 1.33mmfyear in sealevel. Four other ports, Bombay
(1878-1%3), Cochin (7y39-tn8), Madras (19167977) and Visakhapatnam (1937-1978)showed a rise (indicating
relativesinking of land) of 1.28mmfyear,2.Tl mm/year,0.36mmfyear and 0.76 mm/year. respectively.      Data from
these five stations show an averagerise of 0.67 mm/year. Similar studies on a global scale suggesta sea level rise
of 1.0 mm/year to 1.5 mm/year.

Vast areas of land in South Asia could get submerged due to the expected 'global warming' and this global
environmental  problemsis, hence, matter of greatconcernto the region.It is now established the concentration
                                  a                                                         that
of greenhousegasesin the atnosphere has increasedduring tle recent past. Atmospheric concentration of carbon
dioxide, for example,has increasedfrom approximately280 ppm in 1860to around 340 ppm at present. It as been
predicted that the buildup of the gases will increase earth's atmospheric temp€rature. There are, how,ever,
considerableuncertaintiesin the predictions.For example,doubling of carbon dioxide could increasethe temperature
by anythingbetween1.5oCto 4fC.Increased surfaceatnospheric temperaturewill lead to thermal e:rpansion the of
oceansand to melting of polar snow and ice. Consequently,the mean sea level will increase.

During the last century, the global sea level rose by 1G15cm. Over the sameperiod, global warming was estimated
to be about 0.4"C. A rise of qbout 5 c'n in sea level can be linked to thermal expansionbecauseof the global
warming.The remaining5-109m rise hasbeen attributed to deglaciation.      Because little is known about the ratesof
deglaciationdue to global warming it has generallybeen assumed      that the ratio of sea level rise due to thermal
expansion  and that due to deglaciation   will vary between0.5 and 1.0.With such approximations, estimatesof
                                                                                                    the
global sealevel rise for the year 2050vary from 23.8cm to LL6.7cm and for the year ZLffi from 56.2cm to 35.9 cm.
If the sealevel rise of the predictedorder doesoccur,the region of India most wlnerable to permanentsubmersion
will be the Lakshadweep   archipelago.The archipelagoconsistsof 27 separate   coral reefs and islandswith a total area
of 32 sq km. Only 10 of the islandsare inhabited.Accordingto the 1971census' populationof Lakshadweep
                                                                                 the                              w:ls
32,000,thus, -"1'uog it one of the most densely populated regions of the country. The l-alshadweep islands are
lowlyrngwith the highest points not highsl than a few metres above sea level. At present there are no studies
anaiiablein India that give quantitative estimatesof areasthat can be affectedby global warming and the consequent
economicimplications.Studieson such quantificationhave been sponsoredby the Ministry of Environment and
Forests.a mijor diffrculty in measuring level rise is the uncertaintyassociated
                                           sea                                       with the current predictions.

             no                      submersion
In Bangladesh, measurements perrnanent
                          on                   havebeen carried out.

Sinceindependence, incidenceof permanentsubmersion beenreportedin Pakistan.Periodicflooding due to
                     no                               has
                                             elsein the world. Recentstudiesindicate that the seaalong the
high tides in the summer is commonas anyrvhere
coastalareasof Sindh is receding.
                                                I




Pereptions of strengthsand *tatnesses

In Bangladesh, particularstudieshavebeenconducted assess
               no                                    to      permanentsubmersion exceptfor naturalerosion
                                       technology, whole coastalarea is being monitoredby fts lengladesh
in the Joastalareas.Using remote sensing           the
SpaceResearchand Remote SensingOrganisation(SPARRSO).A satelliteground station is receivingdata and
imagery from meteorologicalsatellites of USA and Japan. Pictures are sent regularly to the Meteorologicd
Departmentand Water Development                                                 purposes.
                                   Board for weatherforecasting flood forecasting
                                                              and                          Another station
for receivingimageryfrom resourcesatelliteslike Landsatof USA and SPOT of France is being set up.

India is reasonablycapable predictingcyclones
                            of                                                                     The
                                                sufficiently advance take remedialmeasures' infrastructure
                                                            in        to
to gather necessary                                                                                      of
                     data, to processit and to predict the future courseof eventsexists.The success a cyclone
*"rttiog and mitigation plan, however,dependson the awareness     and understandingof the problem by the people
in immLent danger.A handicapin achievingthe necessary      levelsof public education is the low literacy rate and low
standardsof living which makespublic educationand information difhcult. Another handicapis the lack of frnancial
resources  which often hampersmitigation plans.

                                                              who can assess process'formulate remedial
For coastalerosion, India has the institutionsand professionals              the
measures, monitor their performance  and undertakecorrectivesteps,if          Measuresto control erosion are
                                                                     necessary.
generallyexpensive                             is
                   and availabilityof resources often a problem.

In Maldives,a fgll fledged 6inistry was established 1988to deal with environmentalmatters in the country.In
                                                     in
October 1989,a national workshopwas organised take note of all the recommendations
                                                   to                                        containedin available
reports and expert studies and has laid down the directive principles and framework for action. The national action
plan identifies specificareas for the assessment statusand areasof immediate'priority. There are no precise
                                                 of
iecords of long term tidal variations in Maldives. Two tide gaugeswere installed in Male in June 198? with the
assistance Hawaii University and the Lanka Hydraulic Laboratory.
          of

Nepal being a land-locked country does not face the hazardsassociated with coastal areas.However, freak storms
do occur as an aberration though the phenomenonhas neither been carefully monitored nor analysed.
                                                                    PakistanCentre of Scientific and Industrial
In Pakistan,existing institutions like the Institute of Oceanoglaphy,
Research, Departmentof Meteorology,and Spaceand Upper AtmosphereResearchCommissionhave capabilities
to conductstudiesand assess problem.Formulationof remedialmeasures however,the responsibility many
                              the                                         is,                          of
agenciesand more concerted efforts are required.

In Sri Lanka,the CoastConservation      Departmenthad prepareda coastalerosionmanagement       plan in 1985,whose
implementationcommencedin 1988.To date three major            projects have been undertaken:the Negombo Coast
ProtectionScheme,    Moratuwa Coast ProtectionScheme,      and the Coast protectiveschemebetweenBeruwelaand
Weligamamainlyin areas     wherethe highway threatened erosion.
                                             is           by         There is no informationregatdingthe damages
cau.ed by erosion in economic terms. However, public and       private investments in protecting the shoreline are
significant.In addition, severalhotels haveimplementedprotection schemes their own cost. Relief, however,is not
                                                                            at
granted regularly to those living in temporary housingunits located on the beachwhen they are damagedby erosion.
Relief is usuallygrantedby the governmentagentor by the Ministry of Fisheriesif those affectedare fishermen.




                                                         170
Table 14.1

Classifidftn   of Cydmic distubonccs (WIIIO/ESCAP)


 Low pessure sptcm          Wind speedsnot exceedingL5 knots
                            (27 km/hour)
 Depression                 Wind speedsbetween 16 knots and
                            33 knots (59 kn/hour)

 Qrclonic stmm              Wind speedsbetween34 knots and
                            63 knots (113 km/hour)
 Sercre cyclm€              Wind speedsgvsseding64 knots


Table t4.2

r endh of C-oastlincin Difrerent Comtrfox of SouthAsia


 Country                   I ength of Coastlire

 Bangladesh                        NA
 Bhutan
 India                          7500 KM
 Maldives                          NA
 Nepal
 Pakistan                          NA
 Sri Lanka                      1585KM

NA : Not Available


Table 14.3

Number of cyclmic stams that fanned during 1891-ilm


               Jan   Feb    Mar     Apr    May     Jrm   Jul   Aug   Sep    ft    Nov
 Bay of         51            419            39    35    38    26     32     62    68     %3
 Bengal        (1) (1)       (2)  (8)       (26)   (4)   (7)   (1)   (10)   (%)   (33)   (133)
 Arabian        20            05             16153              )     5202598
 Sea           (0) (0)       (0)     (4)    (13) (10)    (0)   (0)   (1)  (7) (1e)       (55)

Figures within brackets denote the number of storms in which winds exceeded48 knots
Table 14.4

Total number of ctdmic stams reac.hing F{S Coast of gsi f -'rkr
                                      thc


 Month             Number Year
 January           1     (1e06)
 February         0
 March             1     (1e07)
 April            0
 May              0
 June             0
 July             0
 August '         0
 September        0
 October          0
 November                (1922,L96, 1979)
 December         6      (L908,1912,
                                   t9L3,


Table 14.5

Number of Deaths due to Cldmic Storms in nanglafuh


 Date             Stormssurge     Nrrmberof peoplekilled          Number of
                  height (i" m)                                    people
                                                                   mrsSrng
 11.10.60         4.5                  3000
 31.10.60         6.1,                  5L49
 09.05.61         2.+3                11468
 28.05.63         2.+3.6              LLs?n
 11.05.65         3.6                 LTng
05.11.65          2.+3                   873
 17.L2.65         6.L-6.6         Great loss of life              1000
01.11.65          3-10                  850
 r2.r1.70         2.7-5.1            200000 (officially)
                                  7/ffi     (unofficially)
28.IL.74         2.L-4.5                   m                       2ffi
10.12.81         NA                      72
15.10:83         1.5                     43                       7r(f,.
09.11.83         4.5                                              300
24.05.85         0.6-4.2               42il                       6805
29.11.88                               6L33                       6000
Table 14.6

Damage to infrastructurrebyquinds          in MaldivEs (May 191)


             Atoll       Nunbcr of Houses

 Fadhippolhu Atoll                   2t4
 MdC Atoil                           L23
 Ari Atoll                          4y
 Feride Atoll                        48
 Mulaku Atoll                        L39
 N. Nilande Atoll                    159
 S. Nilande Atoll                    160
 KolhumaduluAtoll                    t26
 HadhdhunmathiAtoll                 388
 N. Huvadhoo Atoll                   r23
 S. HuvadhooAtoll                   2U
           Atoll
 Fuehmurlaku                           2
 Addu Atoll                         1881
 TOTAL                              zlml




                                                       L73
  Table 14.7

 Activities cmtributing to coastal ermion in Sri I anlre


   CasualAgent            Process                  Effeds                          Examplesof sites
   Beachsandmining        reductionof sandin       increased
                                                           erosion                Panadura"Lunawa,
                          beachmaintenance                                        Angulana, Palliyawatta
                          system
   River sandmining       -do-                     increased  erosionof           Kalu Ganga,Kelani
                                                   adjacent  beaches,erosion      G^tlg\ Maha Oya
                                                   of river banks
   Inland coral mining    conversion of            development inland
                                                                 of               Akuralq Kahawa,
                          productive land          wastedumpsand                  Ahangam4 Midigama
                                                   abandoned   pits. Reduction
                                                   of coastalstability by
                                                   creation of lowJying areas
  Collectionof coral     reductionof beach         increasederosion               From Ambalangodato
  from beaches           nourishmentmaterial                                      Hikkaduwa,lyfidigemx,
                                                                                  Ahangama and Polhena
  Reef breaking          reductionof reef size, increasedwave energy on           Ambalangodato
                         creationof gapsin      beaches resultingin               Hikkaduwa, Koggala,
                         reef                   erosion                           1,{idigama,
                                                                                            Polhena,
                                                                                  Rekawa,Pasikudah
                                                                                  Kuchchaveli,Nilaveli
  Reef dpamiting                                  -do-                            -do-
  and breaking for
  fishery activity
  Improperly sited       interference with        erosionin someplaces,           BeruwelaFishery
  harbours,              natural sand             accretionin others              Harbour, Kirinda
  revetmentsjetties      transport processes                                      Fishery Harbour
  Improperly sited       interference with        loss of structure,other        Hakkaduwq Bentota,
  coastalbuildings       dpamic of coastal        propertydue to retreat         Beruwela,Negombo
                         processes
  Improper removal     exposedare:$ are           increased
                                                          erosion                Palliyawatta,Koggala,
  of coastalvegetation subjectto more rapid                                      Polhena"Negombo
                       rates of erosion


Table L4.8

Major storn suqges the Bay of B€4al since 19j0
                 in


 Sr.    Dates of Stcm             Metecological            Storn SurgsAspects             Ca$nlties ad
 xg                               Aspeds                                                  Danages
 1.     November1952              l,andfall at             Area Affected : Coromandel     Several
                                  Nagapattinam,            Coastand Northern Shoresof     thousanddeaths
                                  Tanil Nadu, India        Palk Bay. Peak surge of 3 m    in India
        2l to 24 October 1958     Winds of 89 km/hr        Peak surge of 2 m in India

Source: Murty et al. (1986)
 Table 14.9

 Perepios     of strengtbs and*eahscs

Country                     Stre4ths                                      Weatncsses

Bangladesh             L.Data being received at satellite ground     1.   kck of research, except on natural
                         station from Japan and USA                       erosionof coastalareas
                      2. Coastal area being monitored by the
                         Sangl3dgsf, Space Research and
                         Remote SensingOrganisation

Bhutan                                     NA                                             NA

India                 1. Adequateinfrastructureto gatherdata,        1.   Inadequate awareness, low levels of
                         proc€ssand predict cyclones                      information disseminationto the public
                      2. Existence of institutions and                    to facilitate cyclone warning and
                         professionals asses
                                     to       coastalerosion              mitigation plans
                                                                          lack of frnancial resourcesto undertake
                                                                          cyclone mitigation measures and to
                                                                          control coastalerosion

Maldives              1.    A national plan and a framework of       1. No long term records of tidal variation
                            action available
                      )     Tide gauges have been installed to
                            monitor tidal variations

Nepal                                                                L.   Lack of storm monitoring and analpes

Pakistan              t.    Institutional researchfacilities exist
                            ad studieshave been conducted
                      L     lmplementation of a coastal erosion
                            manag€ment     plan
                      ,)
                            Substantialprivate and public
                            investment in protecting the
                            shoreline

Sri Lanka             1. Implementation of a coastal erosion         t.   I-ack of regular relief to those living on
                        managementplan                                    the tieach, in temporary housing units,
                     2. Substantial private and public                    damagedby erosion.
                        investmentin protecting the shoreline             Lack of research on the economic
                     3. Development of a Coastal Tnne                     implicationsof erosion damage
                        ResourcesManagementPlan - Coast
                            2m


NA : Not Available




                                                      L75