Bangladesh Under Siege:Bangladesh Under Siege: A geographicalA geographical examinationexamination of a country at the mercy of amplifying of a country at the mercy of amplifying

natural forcesnatural forcesTeacher: Brian McCabeTeacher: Brian McCabe

Lesson AgendaLesson Agenda

► Part onePart one► Overview of why a study of Overview of why a study of

Bangladesh is important.Bangladesh is important.► A general look at location, A general look at location,

place, and region. place, and region. ► Bangladesh (regional) climate Bangladesh (regional) climate ► ActivityActivity► Part twoPart two► Natural disadvantagesNatural disadvantages► Human impact of calamitiesHuman impact of calamities► Potential impact from global Potential impact from global

warmingwarming► QuizQuiz

ObjectivesObjectivesStudent will be able to:Student will be able to:

► Locate Bangladesh on a map and identify its latitudinal Locate Bangladesh on a map and identify its latitudinal position.position.

► Discuss the importance of studying Bangladesh.Discuss the importance of studying Bangladesh.► Analyze and discuss the geography of Bangladesh and the Analyze and discuss the geography of Bangladesh and the

surrounding region.surrounding region.► Describe what Bangladesh is like.Describe what Bangladesh is like.► Discuss Bangladesh and regional climateDiscuss Bangladesh and regional climate► Identify and analyze natural disadvantages and appreciate Identify and analyze natural disadvantages and appreciate

their history of natural disasters.their history of natural disasters.► Understand the potential impact of global warming on Understand the potential impact of global warming on

Bangladesh.Bangladesh.

Why is the study of Bangladesh Why is the study of Bangladesh important?important?

► In many ways, Bangladesh is a In many ways, Bangladesh is a geographical “ground zero” geographical “ground zero”

► Bangladesh is vulnerable from tropical Bangladesh is vulnerable from tropical cyclones, storm surges, coastal erosion, cyclones, storm surges, coastal erosion, and back water effect.and back water effect.

► Their death rate from these natural Their death rate from these natural disasters are among the highest in the disasters are among the highest in the world.world.

► It is nation of 140 million people (3X less It is nation of 140 million people (3X less just 80 years ago). just 80 years ago).

► About the size of Arkansas, Bangladesh About the size of Arkansas, Bangladesh has about 2,350 people per square mile- has about 2,350 people per square mile- making the most population dense making the most population dense nation in the world (Arkansas has only nation in the world (Arkansas has only 2.5 million people at about 50 per sqm). 2.5 million people at about 50 per sqm).

► Over 50 % of Bangladeshis live well Over 50 % of Bangladeshis live well below the poverty level, making it one below the poverty level, making it one of the poorest nations of Earth.of the poorest nations of Earth.

► About 82% of the population lives in About 82% of the population lives in rural areas. Urban growth was limited by rural areas. Urban growth was limited by poor infrastructure and conditions. poor infrastructure and conditions.

LocationLocation, Place, Region, Place, Region► Pass out map handoutPass out map handout► Keep this map in front of you and Keep this map in front of you and

we will periodically add to it. we will periodically add to it. ► Locate Bangladesh and shade it in, Locate Bangladesh and shade it in,

neatly.neatly.► Locate the Tropic of Cancer at 23.5 Locate the Tropic of Cancer at 23.5

degrees north. Draw a line from left degrees north. Draw a line from left to right, where this latitude would to right, where this latitude would be. be.

► Locate India and Myanmar and Locate India and Myanmar and label them.label them.

► Locate the Himalayan range and Locate the Himalayan range and neatly shade in where it would be neatly shade in where it would be on a completed map. on a completed map.

► Locate the Bay of Bengal, Indian Locate the Bay of Bengal, Indian Ocean, and the Arabian Sea and Ocean, and the Arabian Sea and label them on map.label them on map.

LocationLocation, Place, Region, Place, Region► TectonicsTectonics► Has Bangladesh always been Has Bangladesh always been

there? there? ► Watch movieWatch movie► Discussion:Discussion:► Was Bangladesh included in this Was Bangladesh included in this

tectonic convergence? tectonic convergence? YesYes► Being on the Eastern end of this Being on the Eastern end of this

convergence, do you think this convergence, do you think this played a role in sculpting played a role in sculpting Bangladesh’s topography? Bangladesh’s topography? Natural Natural drainage zonedrainage zone

► What mountain range was formed What mountain range was formed as a result of this continental as a result of this continental tectonic convergence? tectonic convergence? HimalayasHimalayas

► http://www.asu.edu/http://www.asu.edu/courses/gcu600/gcucourses/gcu600/gcu672a/4Tectonics/Cla672a/4Tectonics/ClassroomResources/CssroomResources/ContDriftSeaAge.movontDriftSeaAge.mov

► An animation of the An animation of the Indian sub-continent Indian sub-continent crashing into Asia.crashing into Asia.

Location, Location, PlacePlace, Region, Region► Characterized by two distinctive Characterized by two distinctive

features: a broad deltaic plain & a features: a broad deltaic plain & a small hilly area replete with rivers. small hilly area replete with rivers.

► About 80% of its land-mass is About 80% of its land-mass is fertile, alluvial lowland delta plain fertile, alluvial lowland delta plain (Plain of Bengal or Lower Gangetic (Plain of Bengal or Lower Gangetic Plain). Plain).

► Most of Bangladesh is < 39 feet Most of Bangladesh is < 39 feet above sea level. above sea level.

► 67% of land is arable (define). 67% of land is arable (define). ► Three mighty rivers combine to Three mighty rivers combine to

form the Sundarbans or “Mouths of form the Sundarbans or “Mouths of the Ganges”: the Ganges, the the Ganges”: the Ganges, the Brahmaputra, and the Meghna Brahmaputra, and the Meghna (aka: the GBM river system). These (aka: the GBM river system). These rivers accommodate Himalayan rivers accommodate Himalayan snow melt and monsoonal snow melt and monsoonal watershed!watershed!

Location, Location, PlacePlace, Region, Region► The Sundarbans are home to the The Sundarbans are home to the

largest mangrove forest in the largest mangrove forest in the world.world.

► The GBM River System deposits The GBM River System deposits mineral rich silt into delta region mineral rich silt into delta region making it highly fertile. making it highly fertile.

► Agriculture is Bangladesh’s largest Agriculture is Bangladesh’s largest contributor to the economy (jute, contributor to the economy (jute, rice, and tea). rice, and tea).

► The country’s primary religion is The country’s primary religion is Islam, with Hindi , Buddhists, and Islam, with Hindi , Buddhists, and Christians following in that order. Christians following in that order.

► The people have a reputation of The people have a reputation of being wonderfully kind, resourceful, being wonderfully kind, resourceful, and proud.and proud.

► Dhaka, their largest city, has a Dhaka, their largest city, has a population of about 12.5 million population of about 12.5 million people.people.

Location, Place, Location, Place, RegionRegion

► The region of the Indian The region of the Indian subcontinent is sub-tropical. subcontinent is sub-tropical.

► Bangladesh is located on the Bangladesh is located on the Tropic of Cancer @23.5 Tropic of Cancer @23.5 degrees, which means the solar degrees, which means the solar angle is direct on what date? angle is direct on what date? June 21June 21stst or Summer or Summer Solstice.Solstice.

► Because the ITCZ follows the Because the ITCZ follows the sun, the humid, tropical sun, the humid, tropical monsoonal moisture is monsoonal moisture is positioned just south in the positioned just south in the Indian Ocean.Indian Ocean.

► A “High” to “Low” air flow A “High” to “Low” air flow either saturates this region or either saturates this region or causes drought. causes drought.

ClimateClimate► Three seasons are recognized in this region: Three seasons are recognized in this region: ► Hot & humid summer from March-JuneHot & humid summer from March-June► Cool & very rainy monsoon from June-October.Cool & very rainy monsoon from June-October.► Dry winter from October-March.Dry winter from October-March.► These seasons are driven by several factors: These seasons are driven by several factors: ► Although Bangladesh is located in the Easterly Although Bangladesh is located in the Easterly

Trade Wind zone under the Hadley cell, the Trade Wind zone under the Hadley cell, the presence of reliable “Highs” and “Lows” drive presence of reliable “Highs” and “Lows” drive moisture level and winds. moisture level and winds.

► During the winter, a Siberian “High” sends cool During the winter, a Siberian “High” sends cool dry air from Russia. However, in summer, the dry air from Russia. However, in summer, the High becomes a Low and a High forms over the High becomes a Low and a High forms over the Oceans of Southeast AsiaOceans of Southeast Asia

► Because of high pressure, air flows from High Because of high pressure, air flows from High to Low. This means hot, humid air flows to Low. This means hot, humid air flows towards the Low over Asia. towards the Low over Asia.

► This moist air flow then hits the Himalayas, This moist air flow then hits the Himalayas, rises, condenses and creates intense rainfall.rises, condenses and creates intense rainfall.

► Rainfall can range from 60 to 160 inches a Rainfall can range from 60 to 160 inches a year!year!

► Pull out map handout and draw arrows Pull out map handout and draw arrows indicating monsoonal northeasterly flow. indicating monsoonal northeasterly flow. Indicate High and LowIndicate High and Low..

ClimateClimate

► Remember the GBM River Remember the GBM River System? During monsoon System? During monsoon season, the GBM flows at season, the GBM flows at about 140,000 cubic meters about 140,000 cubic meters per second (only 7,000 per second (only 7,000 during dry season). during dry season).

► They are also the vehicle for They are also the vehicle for immense Himalayan immense Himalayan watershed from melting watershed from melting snow.snow.

► Research has been done Research has been done linking snow depth with linking snow depth with ENSO conditions with GBM ENSO conditions with GBM flow volume. flow volume.

What does all this mean?What does all this mean?

►140 million people mostly in poverty140 million people mostly in poverty► In a country which is 80% below 39 feet In a country which is 80% below 39 feet

above sea-level (most living at or just above sea-level (most living at or just above SL)above SL)

►With the most intense monsoonal rainfall With the most intense monsoonal rainfall on the planeton the planet

►Positioned on the delta of one of the Positioned on the delta of one of the largest high flowing river systems in the largest high flowing river systems in the world.world.

►Hmm? Hmm?

Questions? Questions?

ACTIVITY: 4 groupsACTIVITY: 4 groups

► Group 1 and 2 will:Group 1 and 2 will:► Take two paper towels and get Take two paper towels and get

them wet.them wet.► Then, on a flat surface, push Then, on a flat surface, push

one towards the other, until it one towards the other, until it collides.collides.

► Push until a large ripple Push until a large ripple representing the Himalayas representing the Himalayas forms.forms.

► Then shape the lower towel like Then shape the lower towel like India and on the right corner, India and on the right corner, tear the napkin slightly to look tear the napkin slightly to look like Bangladesh. like Bangladesh.

► This activity illustrates the This activity illustrates the tectonic history of the Indian tectonic history of the Indian sub-continent. sub-continent.

► Group 3 and 4 willGroup 3 and 4 will► Take tape and mark the floor Take tape and mark the floor

with three evenly separated with three evenly separated pieces. Mark top one “Tropic of pieces. Mark top one “Tropic of Cancer” the middle “Equator” Cancer” the middle “Equator” and the lower “Tropic of and the lower “Tropic of Capricorn”. Capricorn”.

► Then write June 21Then write June 21stst on Cancer on Cancer September 21September 21stst and March 21 and March 21stst on Equator and December 21on Equator and December 21stst of Capricorn. of Capricorn.

► Choose a student to take a Choose a student to take a helium balloon and slowly walk helium balloon and slowly walk from one tape to another and from one tape to another and observe the balloon lagging observe the balloon lagging behind. behind.

► This is an example of how the This is an example of how the ITCZ lags behind the sun, ITCZ lags behind the sun, causing a late monsoon season. causing a late monsoon season.

Part 2Part 2

Natural Disadvantages: Natural Disadvantages: A closer A closer looklook

Nature’s ArsenalNature’s Arsenal

► Tropical CyclonesTropical Cyclones► Storm Surges Storm Surges ► Coastal Erosion Coastal Erosion ► Back-water effectBack-water effect► DiseaseDisease

► DroughtDrought

Human DisadvantagesHuman Disadvantages

► Most are poorMost are poor► Shortage of land to Shortage of land to

accommodate peopleaccommodate people► Poor food securityPoor food security► Poor healthcarePoor healthcare► Low literacy (28%)Low literacy (28%)► Zia International Zia International

Airport floods, Airport floods, inhibiting aid. inhibiting aid.

Tropical CyclonesTropical Cyclones► About 80 tropical cyclones (TC) of About 80 tropical cyclones (TC) of

significance form in the world’s significance form in the world’s oceans, yearly.oceans, yearly.

► 6.5% form in the Indian Ocean6.5% form in the Indian Ocean► Frequency of TC in the Bay of Frequency of TC in the Bay of

Bengal is 5-6 times that of the Bengal is 5-6 times that of the Arabian Sea (5.5% of world storms)Arabian Sea (5.5% of world storms)

► Bangladesh is only hit with .93% of Bangladesh is only hit with .93% of all world tropical stormsall world tropical storms

► Is Bangladesh safe, then? Is Bangladesh safe, then? NONO► If you look at all storms with >5000 If you look at all storms with >5000

deaths, 16 of 35 were in deaths, 16 of 35 were in BangladeshBangladesh

► 53% of all world deaths related to 53% of all world deaths related to these storms were in Bangladesh!!! these storms were in Bangladesh!!! India was second. India was second.

► Together, they are hit by only Together, they are hit by only 4.27% of all world storms.4.27% of all world storms.

Tropical Cyclones: HistoryTropical Cyclones: History

► Bangladesh made this Bangladesh made this list 16 times, with the list 16 times, with the highest number of highest number of deaths.deaths.

► More severe storms More severe storms caused deaths to rise in caused deaths to rise in 1998, 2001 and as 1998, 2001 and as recently as July of 2007 recently as July of 2007 (800 dead so far).(800 dead so far).

Storm SurgesStorm Surges► Storm surges are generated Storm surges are generated

by the winds and atmospheric by the winds and atmospheric pressure changes induced by pressure changes induced by cyclones.cyclones.

► Wind moves water and a Wind moves water and a surge occurssurge occurs

► Bangladesh has recorded Bangladesh has recorded surges up to 10 meters (about surges up to 10 meters (about 30 feet) not uncommonly30 feet) not uncommonly

► These surges force sea water These surges force sea water up river estuaries, even up river estuaries, even reversing river flow, on reversing river flow, on occasionoccasion

► Salt water surges up stream Salt water surges up stream causing flooding and killing causing flooding and killing crops.crops.

Coastal ErosionCoastal Erosion

► GBM River System has GBM River System has heavy dischargeheavy discharge

► Wave action from intense Wave action from intense monsoon windsmonsoon winds

► High astronomical tidesHigh astronomical tides► Storm surges all contribute Storm surges all contribute

to coastal erosion and to coastal erosion and accretion. accretion.

► The mangrove trees are the The mangrove trees are the best defense against these best defense against these forces, but are shrinking. forces, but are shrinking.

Back Water EffectBack Water Effect► This is the retardation of a river outflow by the rise in the level of This is the retardation of a river outflow by the rise in the level of

water at the mouth.water at the mouth.► Storm surges create intense backwater effect.Storm surges create intense backwater effect.► This occurs mostly in Bangladesh’s Meghna River estuary, through This occurs mostly in Bangladesh’s Meghna River estuary, through

which about 90% of the river water in the country discharges. which about 90% of the river water in the country discharges. ► When this effect occurs, sea water pushes back on out-flowing river When this effect occurs, sea water pushes back on out-flowing river

water, thereby flooding the interior. water, thereby flooding the interior.

DiseaseDisease

► In 1988 a study was done to In 1988 a study was done to examine patterns of illness examine patterns of illness in post-flood Bangladesh.in post-flood Bangladesh.

► Of 46,740 patients Of 46,740 patients examined, 34% contracted examined, 34% contracted severe diarrhea, 17.4% severe diarrhea, 17.4% contracted respiratory track contracted respiratory track infections, 47% had watery infections, 47% had watery diarrhea diarrhea

► Other diseases that spiked Other diseases that spiked concurrently with SLR was concurrently with SLR was Cholera and water-born Cholera and water-born illness illness

Human ImpactHuman Impact► The frequency of natural calamities the The frequency of natural calamities the

limited ability to cope with it has led to limited ability to cope with it has led to despair, among many Bangladeshis.despair, among many Bangladeshis.

► On top is a dead baby floating in the On top is a dead baby floating in the slums polluted river and below is a man slums polluted river and below is a man using heroine.using heroine.

► HIV is on the rise- currently 5% of the HIV is on the rise- currently 5% of the population is infected and estimates population is infected and estimates suggest that by 2030, 8% will be suggest that by 2030, 8% will be infected. infected.

► Driving the spread of HIV is the increase Driving the spread of HIV is the increase in prostitution. Though minuscule in prostitution. Though minuscule compared to a neighbor like Thailand or compared to a neighbor like Thailand or India, many Bangladeshi women have India, many Bangladeshi women have few options available. few options available.

► Needle sharing is also a problem: In a Needle sharing is also a problem: In a study, it was found that of the 5,000 study, it was found that of the 5,000 heroine users surveyed, up to 80% heroine users surveyed, up to 80% share needles. Dhaka has set up safe share needles. Dhaka has set up safe needle dropping stations. needle dropping stations.

Human ImpactHuman Impact

► http://video.google.http://video.google.com/videoplay?docicom/videoplay?docid=5149498932673d=5149498932673486391&q=Banglad486391&q=Bangladesh+floods&total=6esh+floods&total=69&start=0&num=19&start=0&num=10&so=0&type=sear0&so=0&type=search&plindex=0ch&plindex=0

► Watch movie (3:14)Watch movie (3:14)► Copy & paste on Copy & paste on

browserbrowser

► http://www.cnn.com/video/#/vihttp://www.cnn.com/video/#/video/world/2007/08/04/gallaghedeo/world/2007/08/04/gallagher.india.floods.am.cnnr.india.floods.am.cnn

► Watch movie (1 minute)Watch movie (1 minute)

► http://www.cnn.com/video/#/vihttp://www.cnn.com/video/#/video/weather/2007/08/01/vo.badeo/weather/2007/08/01/vo.bangladesh.floods.reutersngladesh.floods.reuters

► Watch movie (1 minute)Watch movie (1 minute)

Human ImpactHuman Impact

GlobalGlobal WarmingWarmingAs if Bangladesh needs another problem…As if Bangladesh needs another problem…

GlobalGlobal WarmingWarming

►What are the projected side-effects of What are the projected side-effects of global warming?global warming?

►Sea-level rise (SLR)Sea-level rise (SLR)►A 2-4 degree Celsius rise in Sea A 2-4 degree Celsius rise in Sea

Surface Temperature (SST) Surface Temperature (SST)

GlobalGlobal Warming: SSTWarming: SST

► Now, if you apply those projected side-effects to Bangladesh, Now, if you apply those projected side-effects to Bangladesh, the following outcomes have been proposed by researchers:the following outcomes have been proposed by researchers:

► Using high cyclonic frequency zones on the planet (western Using high cyclonic frequency zones on the planet (western North Pacific and the Pacific west of Central America and later North Pacific and the Pacific west of Central America and later the eastern Atlantic off the coast of Africa) scientists have the eastern Atlantic off the coast of Africa) scientists have identified that SST and cyclonic frequency are likely related. identified that SST and cyclonic frequency are likely related.

► Although no direct data supports a link in the Bay of Bengal, if Although no direct data supports a link in the Bay of Bengal, if you look at the 115 cyclones from 1877 to 1990 and the 250 you look at the 115 cyclones from 1877 to 1990 and the 250 cyclonic storms that barely lasted a day, or hit land, and then cyclonic storms that barely lasted a day, or hit land, and then ask whether that would be the case with a 2-4C rise in SST. ask whether that would be the case with a 2-4C rise in SST. Some think a percentage of these storms would have Some think a percentage of these storms would have upgraded. upgraded.

► A greater SST may result in a greater convective instability- A greater SST may result in a greater convective instability- leading to an increase in wind speed. The potential result: leading to an increase in wind speed. The potential result: higher storm surgeshigher storm surges

GlobalGlobal Warming: SLRWarming: SLR► A SLR (sea level rise) would only intensify the amplitude of A SLR (sea level rise) would only intensify the amplitude of

these projections. these projections. ► Coastal erosion will suffer greater, under global warming Coastal erosion will suffer greater, under global warming

conditions. The formula by Bruun (1962) has been used to conditions. The formula by Bruun (1962) has been used to formulate SLR effects:formulate SLR effects:

► x= ab/ (e+d) x= ab/ (e+d) ► x:x: shoreline recession due to SLR shoreline recession due to SLR aa: rise in water from SLR : rise in water from SLR ee: :

elevation of shoreelevation of shore► d: d: depth of water at a distance and depth of water at a distance and bb distance from coastline distance from coastline► Formula results: coastal erosion due to SLR is about 87 times Formula results: coastal erosion due to SLR is about 87 times

the SLRthe SLR► Example: If SLR is .30 m then the coastal recession will be .18 Example: If SLR is .30 m then the coastal recession will be .18

to .39 m per 1 cm rise of oceanto .39 m per 1 cm rise of ocean

Hope and the FutureHope and the Future

► Bangladeshis are wonderfully Bangladeshis are wonderfully optimistic and resourceful.optimistic and resourceful.

► Efforts are being made to Efforts are being made to afforest the mangrove afforest the mangrove protection zones in the delta.protection zones in the delta.

► Flood-deterrent construction Flood-deterrent construction projects are being engineered.projects are being engineered.

► Bangladesh government is Bangladesh government is sponsoring and building many sponsoring and building many cyclone shelterscyclone shelters

► Zia International airport is Zia International airport is looking to raise runways and looking to raise runways and build flood deterrent walls, so build flood deterrent walls, so that aid may get in.that aid may get in.

► Better warning systems are Better warning systems are being put in place. being put in place.

Questions?Questions?

SourcesSources

►See Lecture NotesSee Lecture Notes