Introduction $arious disasters like earthquake, ea rthquake, landslides, volcanic eruptions, fires, flood and cyclones are natural haards that kill thousands of people and destroy billions of dollars of habitat and property each year. The rapid growth of the world%s population and its increased concentration often in haardous environment has escalated both the frequency and severity of natural disasters. With the tropical climate and unstable land forms, coupled with deforestation, unplanned growth proliferation non!engineered constructions which make the disaster!prone areas mere vulnerable, tardy communication, poor or no budgetary allocation for disaster prevention, developing countries suffer more or less chronically by natural disasters. &sia tops the list of casualties due to natural disaster. &mong various natural haards, earthquakes, landslides, floods and cyclones are the ma'or disasters adversely affecting very large areas and population in the Indian sub! continent. These natural disasters are of (i) geophysical origin such as earthquakes, volcanic eruptions, land slides and (ii) climatic origin such as drought, flood, cyclone, locust, forest fire. Though it may not be feasible to control nature and to stop the development of natural phenomena but the efforts could be made to avoid disasters and alleviate their effects on human lives, infrastructure and property proper ty.. ising frequency, amplitude and number of natural disasters and attendant problem coupled with loss of human lives prompted the eneral &ssembly of the *nited +ations to proclaim --s as the International /ecade for +atural /isaster eduction (I/+/) through a resolution 001234 of /ecember 22, -5- to focus on all issues
related to natural disaster reduction. In spite of I/+/, there had been a string of ma'or disaster throughout the decade. +evertheless, by establishing the rich disaster management related traditions and by spreading public awareness the I/+/ provided required stimulus for disaster reduction. It is almost impossible to prevent the occurrence of natural disasters and their damages. 6owever it is possible to reduce the impact of disasters by adopting suitable disaster mitigation strategies. The disaster mitigation works mainly address the following7 (i) minimise the potential risks by developing disaster early warning strategies, (ii) prepare and implement developmental plans to provide resilience to such disasters, (iii) mobilise resources including communication and tele!medicinal services and (iv) to help in rehabilitation and post!disaster reduction. /isaster management on the other hand involves7 (i) pre!disaster planning, preparedness, monitoring including relief management capability. (ii) prediction and early warning. (iii) damage assessment and relief management. /isaster reduction is a systematic work which involves with different regions, different professions and different scientific fields, and has become an important measure for human, society and nature sustainable development.
Role of Space Technology "pace systems from their vantage position have unambiguously demonstrated their capability in providing vital information and services for disaster management ( 8ig.).The 9arth :bservation satellites provide comprehensive, synoptic and multi temporal
coverage of large areas in real time and at frequent intervals and %thus% ! have become valuable for continuous monitoring of atmospheric as well as surface parameters related to natural disasters(Table!). eo!stationary satellites provide continuous and synoptic observations over large areas on weather including cyclone! monitoring. ;olar orbiting satellites have the advantage of providing much higher resolution imageries, even though at low temporal frequency, which could be used for detailed monitoring, damage assessment and long!term relief management. The vast capabilities of communication satellites are available for timely dissemination of early warning and real!time coordination of relief operations. The advent of $ery "mall &perture Terminals ($"&T) and *ltra "mall &perture Terminals (*"&T) and phased ! array antennae have enhanced the capability further by offering low cost, viable technological solutions towards management and mitigation of disasters. "atellite communication capabilities!fi
1. &pplications of space
remote sensing
in
disaster
management /isaster
;revention
9arthquakes =apping geological
;reparedness (Warning)
elief
eodynamic
Locate
measurements
ofstrain stricken
lineaments
areas,
accumulation
land use
mapdamage =apping lava
$olcanic eruptions
Topographi and land use maps
Detection/measurement of gaseous emissions
flows, ashfalls and lahars,map damage
Topographic >andslides
and land use Rainfall,slope stability maps
8lash floods
>and 8lood
plain
=a'or floods maps?
land
use maps
area
rainfall Map
use Local
maps
Mapping slide
flood
measurements
damage
egional
=ap e
rainfall?evapotranspiration floods
>and use and "torm surge land maps 6urricanes
"ea state?ocean surface Map extent of cover wind velocities damage Synoptic
eather Map extent of damage
forecasts
+owcasts? local weather Map amount, Tornadoes
weather extent
>ocal
damage
observations /rought
Long models
ranged
climate
=onitoring vegetative biomass?
of
Drought /rought is the single most important weather! related natural disaster often aggravated by human action. /rought%s beginning is subtle, its progress is insidious and its effects can be devastating. /rought may start any time, last indefinitely and attain many degrees of severity. "ince it affects very large areas for months and years it has a serious impact on economy, destruction of ecological resources, food shortages and starvation of millions of people. /uring -4@!--, droughts have affected A percent of the 2.5 billion people who suffered from all natural disasters and killed 3A percent of the 3.A million people who lost their lives due to natural disasters. :wing to abnormalities in the monsoon precipitation, in terms of spatial and temporal variation especially on the late on set of monsoon, prolonged break and early withdrawal of monsoon, drought is a frequent phenomenon over many parts of India. In India, thirty three percent of the area receives less than @Amm rainfall and is chronically drought!prone, and thirty five percent of the area with @A! 2Amm rainfall is also sub'ect to drought once in four to five years. Thus, 45 percent of the total sown area covering about 02 million hectares are vulnerable to drought conditions. India has faced three ma'or droughts in this century! -0!-A,-4A!44 and -54!5@. The -5@ drought had a lasting impact on one!third of the country. The role of space technology in drought mitigation is enumerated hereunder7
Drought
!reparedness
/rought mitigation involves three phases, namely, preparedness phase, prevention phase and relief phase. In case of drought preparedness, identification of drought prone areas information on land use and land cover, waste lands, forest cover and soils is a pre! requisite. "pace!borne multi spectral measurements hold a great promise
in
providing
such
information.
Drought
!rediction
emote sensing data provide ma'or input to all the three types rainfall predictions? namely such as long!term seasonal predictions, medium range predictions and short!term predictions. lobal and regional atmospheric, land and ocean parameters (temperature, pressure, wind, snow, 9l!+ino, etc.) required for long!term prediction, could be generated from observations made by geo!stationary and polar orbiting weather satellites such as I+"&T and +:&& . In the medium range weather prediction, the +ational Bentre =edium ange Weather 8orecasting (+B=W8) uses satellite!based sea surface temperature , normalised difference vegetation inde<, snow covered area and depth, surface temperature, altitude, roughness, soil moisture at surface level and vertical sounding and radio sonde data on water vapor, pressure and temperature, and vertical profile data in the T541+=B model. In the short!range rainfall prediction also I+"&T! based
Drought
visible
and
thermal
data
are
being
used.
"onitoring
/rought monitoring mechanisms e
rainfall,
weather,
crops
condition
and
water
availability,
etc.
Bonventional methods of drought monitoring in the various "tates in India suffer from limitations with regard to timeliness, ob'ectivity, reliability and adequacy (Ceyaseelan and Thiruvengadachari, -54). 8urther,
the
assessment
is
generally,
influenced
by
local
compulsions. In order to overcome the above limitations, !sponsored a pro'ect titled %+ational &gricultural /rought &ssessment and =onitoring "ystem (+&/&=")% and sponsored by the /ept. of &griculture and Booperation and /ept. of "pace /ept. of "pace (/:") was taken up by the +ational emote "ensing &gency in collaboration with the India =eteorological /epartment (I=/), Bentral Water Bommission (BWB) and concerned "tate overnment agencies. The focus has been on the assessment of agricultural drought conditions in terms of prevalence, relative severity level and persistence through the season. "atellite!derived $egetation Inde< ($I) which is sensitive to vegetation stress is being used as a surrogate measure to continuously monitor the drought conditions on a real !time basis. "uch an e
With the availability of Indian emote "ensing satellite (I") Wi8" data with 55m spatial resolution, the methodology is being updated to provide quantitative information on sowings, surface water spread, and taluk 1 mandal 1block level crop condition assessment along with spatial variation in terms of maps (8ig.2). The I" Wi8" !based detailed monitoring has been opertionalised for &ndhra ;radesh "tate in --5, and subsequently e
Drought
Relief
The "tate overnments are primarily responsible for both short !term and long! term relief management. The +&/&=" provide detailed assessment of drought conditions for providing short !term relief.
Long#term
management$
"everal chronically drought!affected districts in India e
"tate emote "ensing &pplications Bentres, and Bentral round Water Doard and "tate round water /epartments. round water potential maps showing ground water prospect at 72A, scale have been prepared for entire country. The success rate achieved by drilling wells through the use of remote sensing data has been found to be much better than those achieved by conventional means. 8urthermore, as a follow!up large scale (7A,) mapping of ground water prospects for a'asthan, =adhya ;radesh, &ndhra ;radesh, Earnataka and Eerela under a'iv andhi +ational /rinking Water =ission
is
in
progress.
%yclone The intense tropical storms are known in different part of the world by different names. In the ;acific ocean, they are called %typhoons%, in the Indian ocean they are called %cyclones% and over +orth &tlantic, they are called %hurricane%. &mong various natural calamaties, tropical cyclones are known to claim a higher share of deaths and distruction world over. ecords show that about 5 tropical cyclones form over the globe every year. India has a vast coast line which is frequently affected by tropical cyclones causing heavy loss of human lives and property. Byclones occurs usually between &pril and =ay (called pre! monsoon cyclonic storms) and between :ctober and /ecember (called post!monsoon cyclonic storms). While cyclonic storms can%t be prevented, the loss of lives and damage to the properties can be mitigated if prompt action is taken after receiving timely warnings.
yclone
&arning
=eteorologists have been using satellite images for monitoring storms for about thirty years. :ne of the most important applications in this endeavour is to determine the strength and intensity of a storm. In the late -4%s, meteorologists began observing tropical cyclones at more frequent intervals. The infrared sensors aboard polar orbiting satellites began providing day!and!night observations while geo!stationary satellite provided the continuous coverage during daytime. There e
(Eellar,
--@).
& network of !cyclone detection radar covering entire 9ast and West Boasts is being used for cyclone warning each with a range of 0 km. When cyclone is beyond the range of coastal radar, its intensity and movement is monitored with the help of I+"&T, and +:&& series of satellites. The I+"&T provides every three!hourly cloud pictures over the Indian subcontinent. 8or precise location, every half!an!hour pictures are used. Warnings are issued by the &rea Byclone Warning Benters (&BW") located at Balcutta, =adras, and Dombay? and Byclone Warning Benters (BWB) located at Dhubaneswar, $isakhapatnam and &hmedabad. &round disaster warning systems have been installed in cyclone!prone villages of &ndhra ;radesh and Tamilnadu. It is planned to e
administration, /istrict Bollector, "tate overnment officials, etc. The most memorable use of /W" system has been during the cyclone that hit the &ndhra ;radesh coast on may -, --, in evacuating over ,@, people. The information helped saving thousands of lives and livestock in this area. &dditional /W" units are being established to
cover
%yclone
the
entire
coastal
areas
of
the
country.
"anagement
The most striking advantage of the earth observation satellite data has been demonstrated during the recent :rissa super!cyclone event. & severe cyclonic storm with a wind speed about 24 kmph hit the :rissa coast at ;aradip on 2-!oct!-- causing e
I""!III data collected on th :ctober, --- and adarsat "ynthetic &perture adar("&) data of 2nd +ovember, --- since cloud !free optical sensor data over the cyclone!hit area were not available (8ig.3). The map showing inundated area as on 2nd +ov, --- was drapped over topographical map, and was delivered to the :rissa overnment on 3rd +ov,---. Information, thus generated, was effectively used by various departments of :rissa overnment involved in relief operations. "ubsequently, the recession of inundated areas was also studied using adarsat and I" data of Ath,5th,th,3th and 0th +ovember, ---. &n estimated 3.@A lakh ha in Cagatsinghpur, Eendrapara, Dhadrak, Dalasore, Ca'pur, besides Buttack, Ehurda and ;uri districts had been found to be inundated. In addition, the crop
damage assessment was also made and maps along with block!wise statistics derived using pre!and post!cyclone +/$I image from I" Wi8"
data
were
also
provided
to
:rissa
overnment.
'loods India is the worst flood!affected country in the world after Dangladesh and accounts for one!fifth of the global death count due to floods. &bout 0 million hectares or nearly 15th of India%s geographical area is flood!prone. &n estimated 5 million hectares of land are affected annually. The cropped area affected annually ranges from 3.A million ha during normal floods to million ha during worst flood. 8lood control
measures
consists
mainly
of
construction
of
new
embankments, drainage channels and afforestation to save A04 towns and 0@ villages. :ptical and microwave data from I", >andsat 9" and adarsat series of satellites have been used to map and monitor flood events in near real!time and operational mode(8ig.0). Information on inundation and damage due to floods is furnished to concerned departments so as to enable them organising necessary relief measures and to make a reliable assessment of flood damage. :wing to large swath and high repetivity, Wi8" data from I"!B and !/ hold great promise in floods monitoring. Dased on satellite data acquired during pre!flood, flood and post!flood along with ground information, flood damage assessment is being carried out by integrating the topographical, hydrological and flood plain land use1land cover information in a I" environment. In addition, spaceborne multispectral data have been used for studying
the
post!flood
river
configuration, and
e
flood
control
structures , and identification of bank erosion!prone areas and drainage congestion, and identification of flood risk ones.
'lood
Disaster
Impact
"inimi(ation
8lood forecasts are issued currently by Bentral Water Bommission using conventional rainfall runoff models with an accuracy of around 4AG to @G with a warning time of si< to twelve hours. The poor performance is attributed to the high spatial variability of rainfall not captured by ground measurements and lack of spatial information on the catchment characteristics of the basin
such
as current
hydrological land use 1 land cover, spatial variability of soils, etc. Incorporation of remote sensing inputs such as satellite!derived rainfall estimates, current hydrological land use 1 land cover, soil information, etc. in rainfall!runoff model subsequently improves the flood forecast. Improvements in flood forecasting was tested in lower odavari basin in a pilot study titled F"patial 8lood Warning "ystemF. *nder this pro'ect, a comprehensive database including /igital 9levation
=odel
;ositioning
(/9=)
"ystem
generated
(/;"),
using
/ifferential
hydraulic1hydrologic
lobal
modeling
capabilities and a /ecision "upport "ystem (/"") for appropriate relief response has been addressed in collaboration with concerned departments of &ndhra ;radesh overnment. Initial results have been quite encouraging. The deviation in the flood forecast from actual
river
flood
has
been
within
AG.
)arth*ua+e 9arthquakes are caused by the abrupt release of strain that has built up in the earth%s crust. =ost ones of maandsat!T= and ";:T images, and adar interferograms have been used to detect the active faults (=erifield and >amer -@A? Heats et al.--4? =assonnet et al. --3). &reas rocked by >anders earthquake ("outh Balifornia) of magnitude @.3 were studied using 9"! "& interferometry which matched e
been used for earthquake prediction. "pace geodetic technique with lobal ;ositioning "ystem (;") provides an accuracy of a centimetre over km and , thus, helps in measuring the surface deformations and monitoring accelerated crystal deformations prior to earth
quakes
with
required
accuracy.
9arthquake risk assessment involves identification of seismic ones through collection of geological 1 structural, geophysical (primarily seismological) and geomorphologic data and mapping of known seismic
phenomena
in
the
region,
(mainly
epicenters
with
magnitudes). "uch an effort calls for considerable amount of eatur area of =aharastra, India. "pace techniques have overcome the limitations of ground geodetic surveys1measurements and have become an essential tool to assess the movement1displacements along faults1plate boundaries to even millimetre
level
accuracy.
*sing $ery >ong Daseline Interferometry ($>DI), it has been possible to record accurately the plate movement of the order of centimetre
along baseline of hundreds of kilometre. "imilarly, satellite!based lobal ;ositioning system (;") has emerged as a powerful geodetic tool for monitoring (geological) changes over time which is the key for understanding the long!term geo!dynamical phenomena. ;" has been particularly useful in measuring the more comple< deformation patterns across plate boundaries where large and regional scale strain builds up. ;late movements, slips along faults etc. have been measured using differential ;" to an accuracy of sub!centimetres.
olcanic
)ruption
=any times precursors of volcanic eruptions have been observed in various areas of volcanic activity. round deformations, changes in the compositions of gases emitting from volcanic vents, changes in the temperatures of fumaroles, hot springs and crater lakes as well as earth tremors are preceding volcanic eruptions. Thermal infrared remote sensing has been applied for volcanic haard assessment. 6owever, deficiencies of equipment and coverage suggest that thermal infrared has not been adequately evaluated for surveillance of
volcanoes.
The
+ational
emote
"ensing
&gency
has
demonstrated the potential of multi!temporal >andsat!T= thermal band data in the surveillance of active volcanoes over Darren island volcano which erupted during =arch -- to "eptember -- (Dhatacharya et al. --2). In the last three decades, aircraft and satellite!based
thermal infrared (TI)
data
have been
used
e
thermal infrared images from satellites make it an alternative tool for monitoring volcanoes. <hough the spatial resolution of +:&& environment satellite is too coarse to record details of surface thermal patterns, the plumes of smoke and ash from volcanoes could be detected which is useful in planning the rehabilitation of affected areas. "tudies have shown that the upward migration of magma from the earth%s crust 'ust before eruption inflates the volcanic cone. "uch premonitory signs can easily and quickly be detected with the aid of differential "& interferometry. 9
Landslides &erial photographs and large!scale satellite images have been used to locate the areas with the incidence of landslide. 6igher spatial resolution and stereo imaging capability of I" !IB and !/ enable further refining the location and monitoring of landslides. & number of studies have been carried out in India using satellite data and aerial photographs to develop appropriate methodologies for terrain classification and preparation of maps showing landslide haards in the arhwal 6imalayan region, +ilagiri hills in south India and in "ikkim forest area. "uch studies have been carried out using mostly aerial photographs because of their high resolution enabling contour mapping with intervals of better than 2m in height. The availability of m resolution data from the future I" mission may help generating contour maps at 2m intervals making thereby space remote sensing a
highly
%rop
cost
effective
tool
!est
in
landslide
and
onation.
Diseases
:ne of the successful programmes where space technology has been used in risk assessment from crop pests1diseases is the /esert >ocust "atellite &pplications pro'ect of the *+18&: for the International /esert >ocust Bommission. Temporal and spatial distribution of desert vegetation and rainfall derived from +:&&! &$6 data have been used to identify the potential >ocust breeding grounds. In India, the desert locust is epidemic over 2 lakhs sq.km spread over a'asthan, u'arat and 6aryana states. Improved desert locust forecasting system is being tried with the help of satellite data by the locust warning organiations by narrowing down the potential breeding areas to undertake aerial spraying for arresting further growth
of
locust.
'orest
'ire
"everal thousands of hectares of forests are burnt annually due to manmade forest fires causing e
demography,
infrastructure
and
urban
interface
are
considered. 9ffective mitigation of forest fire involves fuel (land cover, weather, terrain, vegetation type and moisture level) mapping, identification of fire risk areas, rapid detection, local and global fire
monitoring and assessment of burnt areas. The analysis of near!real time low spatial resolution (km) and high repetivity data from +:&& and high spatial resolution data with low repetivity from earth resources satellites could provide the information on areas under fire. The I" satellite data have been used for monitoring forest fires over +agarhole
Wild
>ife
"anctuary
of
"outhern
India.
%onclusions &part from loss of human lives, natural disasters inflict severe damage to ecology and economy of a region. "pace technology has made
significant
contribution
in
all
the
three
phases,
i.e.
preparedness, prevention and relief of disaster management. With a constellation of both I+"&T and I" series of satellites, India has developed an operational mechanism for disaster warning especially cyclone and drought, and their monitoring and mitigation. 6owever, prediction of certain events likes earthquake, volcanic eruption and flood is still at e
References -attacharya, A. Reddy, %.S.S. Sri0asta0, S.. 1223, emote sensing for active volcano monitoring in Darren island "outh &ndamans,
India,
using
shortwave
+"&1&1/1T!1-2,
infrared
+"&,
satellite
data.
6yderabad.
4eyaseelan A.T. S.Thiru0engadachari 1256, Burrent /rought monitoring system in &ndhra ;radesh states. eport +o7 I"!*;! +"&!/=!T
3,
+ational
emote
"ensing
&gency,
and
6yderabad. arni+, . Algermissen, S.T., 1275, "eismic oning! Bhapter in the
&ssessment
and
=itigation
of
9arthquake
isk.
*+9"B:,;aris,pp!0@. "assonnet, D. Ad0agna,'. 1228, & full scale validation of radar interferometry :bservation
with
9"!7
The
Juarterly,
>anders
earthquake.
9arth
+o.0.
Rao, D.!. 1225, emote sensing K I" for sustainable development7 &n overview. ;roc. Int. "ymp. on esource and 9nvironmental =onitoring 7 >ocal, regional and global. "ept. !0,--5 Dudapest, 6ungary. Rao, 9.R. 1226, "pace Technology for "ustainable /evelopment. Tata =craw!6ill ;ublishing company >td. +ew /elhi , India. ogel, A. 125:, Bontribution of "pace Technology to 9arthquake ;rediction, esearch, &dv. 9arth :riented &pplication. "pace Technology. "assonnnet, D., ".Rossi, %.%armona, '.Adragna, ;.!elt(er,
.'eigl, T.Rabaute, 1228, The displacement field of the >anders earthquake mapped by radar interferometry7 +ature, v. 340, p. 35! 02. "erifield, !.m. D.L.Lamar, 127<, &ctive and inactive faults in southern california viewed from "kylab7 +&"& 9arth esources "urvey
"ymposium,
+&"& T=
L!A545,
v.
,
p.@@-!@-@.
!rior, D.-., 4.".%oleman, L.).;arrison, 1272, /igitally acquired undistroted
side!scan
sonar
=ississippi
iver
/elta7
images
of
eology,
submarine v.
@,
landslides p.
=eats, R.S., .Sieh, %.A.Al+len, 1226, eology of earthquakes7 :