Download - geogra l5 2
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 1/174
Sand-bar islandsCoral Islands
Types of Islands
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 2/174
formation
• Symbiotic relationshipbetween coral polypsand xooxanthalae
•
Sunlight –depth 50 m• Temp – 25-27 deg
• Salinity –
• !alm" circulating
nutrient rich water• #ot at mouth of ri$er
conditions
!oral reef
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 3/174
Coral bleaching
• !oral polyps expelxooxanthalae understress condition
•
%lobal warming• &'one depletion
• &cean acidi(cation
• Sedimentation
• )arine pollution• diseases
Reasons for
bleaching
!oral reef
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 4/174
•
*ringing reef– barrier reef-atoll
• Subsidence
theory of+arwin
• Standstilltheory of)urray
*ormation of coral reef
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 5/174
,ori'ontal)otion of &cean water
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 6/174
wavesOcean currents
,ori'ontal motion of ocean water
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 7/174
tidesSpring-neap tide
Tides
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 8/174
UpwellingDown-welling
p-welling and down-welling
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 9/174
Temperature of the ocean
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 10/174
• )ain energy source - Insolation
• &ceans play important role in energyand temperature regulation on earth"due to speci(c heat of the water
• .$erage temperature of ocean / -5degree !elsius
• ut a$erage surface temperature ofocean water / 25 degree
Temperature of &cean
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 11/174
• 1atitudinal $ariation
• It decreases fromeuator to poles
• ut highesttemperature is notat the euator butat the tropics
• 3eason4 high
rainfall" cloud co$erhigh albedo6reection ofsunrays8
Temperature 9attern of the &cean
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 12/174
•,emispheric$ariation
•#orthernhemisphere
warmer thansouthern
•3eason4 largeland mass in
northernhemisphere –high energy
Temperature pattern of the &ceans
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 13/174
• :nclosed seas
• )arginal seas oftropics warmerthan open &cean
; marginal seas oftemperate regioncooler than openseas
• 3eason4 lessmixing of water
Temperature pattern of the &ceans
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 14/174
• &cean
currents• <arm
ocean
current –warminge=ect
• !old ocean
currentcoolinge=ect
Temperature pattern of the &ceans
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 15/174
• p-welling and
dow-welling• pwelling bring
cool water from
depth –lowerdown the surfacetemp
Temperature pattern of the &ceans
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 16/174
• +own-welling– piling up ofwarm water –
increase thetemp
Temperature pattern of the &ceans
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 17/174
•
)ax temp of dayand min temp ofnight time
• Tropical waterhigher diurnalrange thaneuatorialwaters
• ecause",eating andcooling of waterrapid underclear s>y
+iurnal range of temperature
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 18/174
•
igger thesi'e of ocean-better mixingof water and
heat• 1ower annual
range
•
9aci(c ocean –lower annualrange than.tlantic &cean
.nnual range of temperature
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 19/174
9relims2007
?@ !onsider thefollowing statements4
A8 .nnual range oftemperature is
greater in 9aci(cocean than in.tlantic ocean
28 .nnual range oftemperature is
greater in northern
9S!
?uestion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 20/174
9relims2007
<hich of the statementis correctB
a8 A only
b8 2 only
c8 oth A and 2
d8 #either A or 2
.ns@ 8
9aci(c &cean – better
9S!
?uestion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 21/174
Ast layer – upto 500m
20-25 deg !8
2nd layer –thermocline 500-A000m
th layer – cold layer–beyond A000m
Certical distribution of temperature
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 22/174
• Temp decreases withincreasing depth
• rate of decrement is
rapid at euator –tropics than towardspoles
• Ast layer – permanent
in Tropics–temperate only insummer
Certical distribution of temperature
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 23/174
Temperature of the ocean
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 24/174
• .mount of salt found in A000 gm ofwater
• #acl 7DE8" )g!l2 AAE8" )gS&F@5E8" !aS&F 2@5E8
• #a and !l has high residual time inocean water – $ery gradual remo$al –
thatGs why" they remain in thehighest proportion
Salinity of &cean water
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 25/174
• Irrespecti$e of absolute salinity of thewater" the proportion of the saltremain same in all parts of the
oceans
• .mount of addition or extraction offresh water compared to salt content
in the &cean water decides absolutesalinity of the &ceans@
Salt udget
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 26/174
• Sediments carried by ri$ers
• Submarine $olcanism at )&3
•
!hemical reaction between roc>s ofgeothermal $ent of $olcano and coldwater
• :rosion of oceanic roc>s
Sources of salts in ocean water
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 27/174
• 9hysical remo$al – wa$es brea> atthe beaches" salt-spray
• iological remo$al – marine life formsextract calcium from sea water fortheir bones
3emo$al of Salts in &cean water
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 28/174
• .ddition of fresh water /H 3ainfall"inow of large ri$er" melting ofglacier /H less salinity
• 3eduction of fresh water /H increasein temperature" high e$aporation"windy wind accelerate the
e$aporation8
Cariation in salinity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 29/174
• Standard salinity of ocean water is /5@5 ppt – salinity of .tlantic &cean
• +ead Sea 50 salinity8" 1a>e $anF008" 1a>e rmia
• )an seldom drowned in sea withhigh salinity
• ecause" high salinity / high density
Salinity of the oceans
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 30/174
• Salinity goesdecrease fromeuator to poles
• ut highest
salinity is not atthe euator /because highrainfall" cloud
co$er• ,ighest salinity
is at tropics
9attern in $ariation of salinity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 31/174
• #orthern
hemisphere –warmer – highe$aporation –saline
• ut in southern9aci(c- roaringF0" furious 50and shrin>ing 0screaming 70 –$ery fast winds
• ,igh e$aporation
/H high salinity
9attern in $ariation of salinity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 32/174
• Ast - &cean
currents• warm ocean
current li>e"
highe$aporation
• !old currentled to p-
welling4 coolerwater fromdepth come atthe surface /H
low salinity
1ocal Cariations in Salinity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 33/174
• 2nd - :nclosed
seas• low latitude -
warmer than open
sea- high salinity• :x@ )editerranean
Sea" 3ed sea
• high latitude-
cooler than opensea – low salinity
• :x@ altic Sea
1ocal Cariations in Salinity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 34/174
• th – inow of
large ri$ers• %anga –
rahmaputra ow
into ay of engal• ay of engal less
saline than.rabian sea
1ocal Cariations in Salinity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 35/174
Mississippi in GofMe!ico
"mu dar#a$ S#r
dar#a to "ral sea
3i$ers inow to the seas
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 36/174
%lac& sea'ersian gulf
3i$ers inow to the seas
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 37/174
• Fth – glaciers
• altic sea recei$efresh water from
melting of glaciers– low salinity
1ocal Cariations in Salinity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 38/174
• Salinity decreases with increasingdepth
• Temp of water decreases
• +ensity of water increases
• Salinity increases density –watersin>s
• Saline water free'e slowly comparedto pure water
Certical pattern of salinity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 39/174
• :uator – salinity increases withdepth upto some layer –thandecreases with depth
• eyond euator – salinity decreaseswith depth
• Certical salinity $ariation of oceans is
complicated• #o uniform layering
Certical pattern of salinity
f
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 40/174
Temperature of oceanwater
$ariations
Salinity of ocean water
Salt budget
$ariations
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 41/174
!limatology
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 42/174
• :arly atmospherehas , and ,e in
abundance-lighter gasesescaped
• +uring early life of
the earth –extensi$e$olcanism-degassing@ #" S"<ater Capour".rgon and !&2came out
&rigin of the .tmosphere on :arth
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 43/174
• <ater $apour
condensed –clouds – rainfall–washed outbul> of the !&2
into &ceans@ !o2/ 0@0E
• &xygen – fromanaerobicrespiration ofbacteria li>e"!ynobacteria
&rigin of the .tmosphere on :arth
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 44/174
Gas 'ropor
tion(itrogen 7DEO!#gen 2AE"rgon 0@JECarbon
dio!ide
0@0E
(eon 0@00AD
E
)elium 0@0000
9roportion of gases
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 45/174
• #" &" , and .rgon are permanentgases
• <ater $apour" !o2" o'one -H $ariable
gases" %,%
• #" .rgon – inert gases
• .tmospheric gases- no chemicalinteraction among them
• They donGt lose their properties
• They act as a single uni(ed gas
9roportion of gases
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 46/174
Structure of atmosphere
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 47/174
• J0E of
atmospherewithin 2 >m
• Tropopause /,eight D >m atpoles" AD >m ateuator
• .t euator
cumulonimbusclouds
Troposphere
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 48/174
• Temperature
decrease as heightincreases
• Transparent toinsolation
shortwa$e8• ,eated by
terrestrial radiation
longwa$e8• %,%s absorbs long
wa$e terrestrialradiation
%reenhouse e=ect in troposphere
?uestio
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 49/174
9relims
20A2
?@ normally" the temperaturedecreases with increase in
height from the earthGssurface" because"
A@ .tmosphere can be
heated upward only fromearthGs surface
2@ There is more moisture in
upper atmosphere@ The air is less dense in
upper atmosphere
9S!
?uestion
?uestio
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 50/174
9relims
20A2
a8 A only
b8 2 and
c8 A and
d8 A"2 and
.ns@ !8
1ess dense / lessamount of %,%s / lowtemp
9S!
?uestion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 51/174
• Temperatureincreases withheight
•
ecause ofthe presenceof o'one layer
• &'one
absorbs Crays fromisolation
stratosphere
?uestio
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 52/174
9relims
20AA
?@ The Ket aircrafts y $eryeasily and smoothly in lower
stratosphere@ <hyBA@ There are no clouds or
water $apour in lower
stratosphere2@ There are no $ertical
winds in lower
stratosphere
.ns@ A in wrong" 2 is correct
9S!
?uestion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 53/174
•
.bsence of %,%s• Temperature
decreases withheight
)esosphere
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 54/174
)esospheric
clouds• !louds $isible
at highlatitudes
• +uring summerseason
• !ondensation
of mixture ofmeteoric dustand somemoisture
#octilucent clouds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 55/174
• Temperatureincrease withheight
•
%ases in ionic state– trap insolation –extremely hot
• ut ions are highly
dispersed• p to D00 >m from
earth
Thermosphere
* D0> t
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 56/174
• *rom D0>m toF0 >m
• #umber ofionic layers
• seful inradio-
communication
Ionosphere
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 57/174
• ,igh energy
sunrays andcosmic raysbrea> the atomsof air molecules –
become ionised;$e charged8
• eha$e as free
particles• .t night time"
only cosmic raysioni'ation -wea>
Ionosphere
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 58/174
la#
ers
heigh
t
+re,u
enc#
'rese
nce
format
ion+ 0-
J0>m1* +ay-
timeSolarradiation
: JJ-A0>m
)*",*
+ay-time
C with#molecule
* A50-D0>m
)*",*
+ayLnight
% HF00> )*" +ay L
1ayers of Ionosphere
? . l i : thG ?uestio
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 59/174
9relims
20AA
?@ . layer in :arthGsatmosphere called
ionosphere facilitates radiocommunication@ <hyB
A@ 9resence of o'one cause
reection of radio wa$esto earth
2@ 3adio wa$es has long
wa$elength
oth statements are wrong
9S!
?uestion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 60/174
• eyond F0 >m
• ,ighly rari(edatmosphere
• Cery high
temperature-but di=erentfrom airtemperature-
because noexistence of air-temp canGt befelt
:xosphere
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 61/174
• %lowing lightsat mid-nightsat high
latitudes• .t height of
exosphere andmagnetospher
e
.urora
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 62/174
• sun emit solarwind6storm fromits corona
• Solar wind
consist of plasmafree electronsand ;$e ions8
• Interaction of
solar wind withearthGsmagnetosphere-disturbance
.urora
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 63/174
• !ollision of charged
particlesisoni'ation8 inmagnetosphere
• Ionised particles
emit light –releaseenergy
• charged particlesinteract with
geomagnetic (eldlines
• Thus" $isible onhigh latitudes
.uroras
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 64/174
• The a$eragetemperature of theearth A5 degree
• :arth maintains inuxand out-ux of theenergy" but out-ux isnot immediate" it haslong time gap@ That is
why" the temperatureis maintained@
,eat budget
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 65/174
• *irst 5Eabsorbed by&'one layer
• Then A5Eby cloud
co$er• &nly 50E
energyreached to
the earthsurface
,eat budget - Incoming
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 66/174
• 20E is lost in
latent heat ofe$aporationA0E lost insensible heat
temperature ofthe body8
• A5E absorbed
by %,%s• 3emaining 5E
was released inthe space
,eat budget - outgoing
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 67/174
• 3atio between thetotal solar radiationfalling upon asurface and theamount reected
• 3epresents as E
• :arthGs a$g@ .lbedo
/ 5E• 1owest- dar> soil
• highest - snowfall
.lbedo
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 68/174
surface "lbedo*resh
snow
D0E-J0E
+esert 5-F5E
%rasses 2E!rops A5E
ri > - A -2
.lbedo - table
? <hich one of the following ?uestio
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 69/174
9relims
20A0
?@ <hich one of the followingreect bac> more sunlight as
compared to other threeBa8 sandy desert
b8 9addy crops
c8 1and co$ered with freshsnow
d8 9rairie land
.ns@ !8
9S!
?n
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 70/174
)ori*ontal
•
when there is pressuregradient
• from high pressure tolow pressure /Had$ection
•
when air get warm"gets expands"becomes lighter /Hmo$e upwards /Hcon$ection
vertical
)o$ement of air
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 71/174
• <hen air gets
hotter thansurrounding air" itrises upward
• If it has moisture -latent heat ofcondensation –more heated – will
go up - formclouds -can bringrainfall /instability
Certical mo$ement of air - instability
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 72/174
• <hen air is coolerthan surrounding –it cannot mo$eupward
• sin>ing air
• atmosphericstability or anti-
cyclonic condition• ,igh pressure on
ground
Certical mo$ement of air - stability
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 73/174
1ow pressure – ,igh pressure
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 74/174
• The rate at which airpac>et cools whilerising
• .$g adiabatic lapserate is @F degree6>m
• That is air pac>etgets cool by @Fdegree afterco$ering one >mupward
.diabatic lapse rate
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 75/174
• if air pac>et has highmoisture content- notget cool so fast@
• Its adiabatic lapse
rate M@F degree6>mN F degree6>m /H<.13
• <et air can reachhigher distances withlow lapse rate /Hcreate instability
<et adiabatic lapse rate
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 76/174
• If air pac>et is dry"
it does not ha$emuch moisture" itwill get cool $eryfast@ )ore than@F degree6>m –li>e" A0degree6>m@
•
+ry air createstable condition
+ry .diabatic 1apse rate
!onditions of stability and
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 77/174
situation condition
!onditionalstability
when wet.13M normal
.13 M dry .13.bsolute
stability
when normal
.13M wet .13M +ry .13
!onditions of stability andInstability
increasingi
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 78/174
increasingheight
temperature of airdecreasing"
but re$erseis
happenedthan it iscalled
tem eratur
Temperature In$ersion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 79/174
• Ast
• .t Tropopause– temperaturestartsincreasing
from here
• So air pac>etreach till here"
start mo$ingdownwards
:x@ &f temperature In$ersion
f i
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 80/174
• 2nd
• . cool winternight" the airabo$e the coldsurface gets cool@
• ut the air layerabo$e that coollayer is till
warmer@ Then" bygoing upward" airdoes not getcooler but warmer
:x@ &f temperature In$ersion
&f i
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 81/174
• th
• Calley in$ersion• winter – cool air
descends to$alley
• plift the warmair of $alley
• +escending
cool air-damage crops-frost
:x@ &f temperature In$ersion
Implications of temperature
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 82/174
+ormation
of fog
arm air cooled
b# cold airbelow .condensation .
tin# waterdroplets- lowvisibilit#
*ormation offrost
<ater moisturefro'en withcontact cold
surface- dama e
Implications of temperaturein$ersion
? <hat do you?uestio
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 83/174
mains20A
?@ <hat do youunderstand by
phenomenon ofOtemperature in$ersionP
in meteorologyB ,owdoes it a=ect weatherand habitants of the
placeB 58
9S!
n
! d ti f t d l t
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 84/174
Condensation ofwater droplet Result
.t heights !louds
.t lower le$el *og
on the cold
surface
+ew
drop Turn into ice
crystal in extreme
*rost
!ondensation of water droplets
3 f f ti f f
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 85/174
"dvection
Moving of warmair over cold
3adiat
ion
<inter nights –
loss of heat dueto terrestial
radiation – coldsurface@ )o$ing of
warm air o$er
3eason for formation of fog
+ i l l f i ibilit
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 86/174
+ecreasing le$el of $isibility
i
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 87/174
fog
•
<ater dropletcondensed around adust particle
• It reduces the$isibility" damage thecrops
• <ater droplet
condensed around aparticle of pollutant"li>e S&2
• 3educe $isibility ;
health ha'ard
smog
comparison
i
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 88/174
Smog• It occurs in warm" dry
and sunny climate
• )ixture unsaturated
hydrocarbons andnitrogen oxides #&28in presence ofsunlight
•
Its components areo'one" nitric oxide"acrolein" andformaldehyde andperoxyacetyl nitrate
9.#8@
'hotochemical smog
comparison
• It occurs in cool humidclimate
• It is a mixture ofsmo>e" fog andsulphur dioxide S&28@
?@ 9hotochemical smog is ?uestio
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 89/174
9relims
20A
? gresultant of reaction among
a8 #&2" & and peroxyacetylnitrate in the presence ofsunlight
b8 !&2" &2 and peroxyacetyl
nitrate in the presence ofsunlight
c8 !&"!&2 and #&2 at low
temperatured8 ,igh concentration of #&2"
& and !& in the e$ening
9S!
n
9hotochemical smog4?uestio
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 90/174
9relims
20A
9hotochemical smog4
#&2" &'one ; sunlight
.ns@ .8
9S!
n
Structure of
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 91/174
atmosphere
Certical )o$ement ofair
.diabatic lapse rate Temperature in$ersion
and its e=ectsfog
precipitation
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 92/174
e$aporationprecipitation
:$aporation
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 93/174
A8 ,igh temperature
28 19 conditions
8 *ast mo$ing wind• <ater $apour
e$aporate from thewater body
• :$aporation addsmoisture in the air
:$aporation
,umidity
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 94/174
"bsolute )umidit#
• <eight of water$apour in unit $olumeof moist air
• <eight of water$apour per unit weightof dry air
Speci/c )umidit#
,umidity
9recipitation
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 95/174
• 9recipitation – whenair is saturated withwater $apour and anyextra addition result
in precipitation3elati$e ,umidity4
• .mount of water$apour present in air
– to amount of water$apour reuired forsaturation
• 9recipitationdepends upontemperature andmoisture content ofthe air
• ,ot air – saturationreach with more
moisture contentthan cold air
9recipitation
Types of clouds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 96/174
Types of clouds
Types of rainfall
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 97/174
Convectional rainfall
Orographic rainfall
Types of rainfall
Types of rainfall
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 98/174
C#clonic rainfall
+rontal rainfall
Types of rainfall
9ressure system of the world
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 99/174
• :ntire earth is di$ided into F large pressurebelts
• In reality" belts are not continuous butpoc>ets of low and high pressure@
• ut pressure can be created throughthermal or dynamic reasons
• Thermal4 high temperature/H 19" low
temperature /H ,9• +ynamic4 air rises /H 19" air descends /H
,9
9ressure system of the world
9ressure system of the world
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 100/174
• F belts4
• euatorial lowpressure belt
• sub-tropical
high pressurebelt
• sub-polar lowpressure belt
• 9olar ,ighpressure area
9ressure system of the world
:uatorial 19 belt
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 101/174
:uatorial 19 belt
• !onstant insolation• .ir gets warm -19
• .ir mo$e upward
-H cloud formation-H instability -Hrain in the e$eningdaily
• !umulonimbusclouds
• !on$ectional
rainfall
:uatorial 19 belt
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 102/174
:uatorial 19 belt
• .bsence ofad$ection of air
• elt of calm 6
+oldrum• ecause light"
feeble winds -calm region
Sub tropical ,9 belt ST,98
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 103/174
• The air abo$e
euator mo$etowards pole" butcoriolis force - theirpath get deected@
•
The length of pathincreases@ Theirenergy reduced inmid-path -cooled@
air subside near 0-F0 deg latitude@
Sub-tropical ,9 belt ST,98
Sub tropical ,9 belt ST,98
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 104/174
• .s descending air
– ,9• +ynamically
induced ,9
• !alled QhorselatitudeG
Sub-tropical ,9 belt ST,98
Sub polar 19 belt S9198
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 105/174
• *rom the pole" cold
winds mo$etowards euator
• The both warmand cold winds
collide" the warmerwinds from ST,9rise abo$e the coldpolar winds
•
This rising ofwarmer wind near50-0 degreecreate 19
Sub-polar 19 belt S9198
9olar high
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 106/174
• .ir risen at
S919"descends atpoles
• ,igh pressure
conditions• Thermally
induced
9olar high
<ind system of the world
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 107/174
<ind system of the world
9lanetary winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 108/174
• winds blowing at
the same directionthroughout the year
• co$er largedistances@
• ,ori'ontalmo$ement"9ressure beltsystem pro$ide
them the pressuregradient
• !orilis force modifytheir direction
9lanetary winds
• The winds mo$eTrade winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 109/174
• The winds mo$etowards euatorial
low pressure /IT!R
• IT!R – intertropicalcon$ergence'one" where windcon$erges
•
Their direction iseast to west dueto coriolis force
Trade winds
Tropical deserts and trade winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 110/174
• Tropical
easterlies ows–east to west
• <ind becomesdry when they
reaches thewestern coast ofthe continents
• &= –shore trade
winds• Trade wind
deserts
Tropical deserts and trade winds
Tropical desert and cold currents
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 111/174
•
2nd• !old currents
pro$idedesiccating
e=ect to tradewind deserts
• !old current
ow onwesternmargins ofcontinents
Tropical desert and cold currents
?@ )aKor hot deserts in ?uestion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 112/174
)ains20A
Knorthern hemisphere
are located between20-0 degree #orthlatitudes and on thewestern side of thecontinents@ <hyB A08
9S!
n
<esterlies
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 113/174
• *rom west to east
• *rom ST,9 to S919
<esterlies
<esterlies
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 114/174
• *rom west to east
•
*rom ST,9 toS919
• 1ess landmass insouthern
hemisphere• *ast owing
winds in the opensea
•
3oaring F0s"furious 50s"shrin>ing 0s andscreaming 70s
<esterlies
?@ <esterlies in southernhemisphere are stronger and
?uestion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 115/174
9relims
20AA
hemisphere are stronger andpersistent than northern
hemisphere@ <hyB
A@ Southern hemisphere hasless landmass as compared
to northern hemisphere2@ !oriolis force is higher in
southern hemisphere ascompared to northernhemisphere
.ns@ A is correct" 2 is wrong
9S!
n
9olar :asterlies
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 116/174
• *rom east towest
• *rom poles to
S919
9olar :asterlies
.pparent mo$ement of the sun
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 117/174
Summer
inter
.pparent mo$ement of the sun
mo$ement of the pressure system
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 118/174
Summer
inter
mo$ement of the pressure system
<ind system of the world
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 119/174
<ind system of the world
Seasonal winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 120/174
• )onsoon winds4
seasonal re$ersalof winds
• *eature oftropical latitude
• In winter – tradewind blows northto south" insummer – trade
wind blows southto north but inlimited area
Seasonal winds
)onson winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 121/174
• +ue to apparentnorthwardmo$ement of thesun in summer@
Thus" the IT!R 198also mo$es upward
• Thus" the area whichwas under northerntrade winds inwinter" will come
under southern tradewinds in the summer
)onson winds
<ind system of the world
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 122/174
<ind system of the world
1ocal winds 4 mountains winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 123/174
Cold wind
countr#
wind
%reece
%ragale
Italy Tremonta
Mountains
ind
.lps *ohn
3oc>ies
!hinoo>
.ndes Ron
arm winds
oca ds ou a s ds
1ocal winds 4 land
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 124/174
Cold wind0 land
• ,9 condition in winter• +i$ergence of cold air
• Siberia – uran
• !anada - li''ard
desert
inds
Sahara Sirocco
:gypt Uhamsin
1ibya %ibli
arm wind0 desert
1ocal winds 4 land
1ocal winds4 India
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 125/174
summer
• ,ot-dusty wind / QlooG
states ind
ihar"
<".ssam
Ualbais
ha>hi
U# losso
mshower
U3 )ango
're-monsoonthunderstorm
1ocal winds4 India
<ind system of the world
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 126/174
y
)ountain bree'e
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 127/174
• +uring night
time4 top getscooler than$alley / ,9"$alley /19
• <ind mo$e hill-top to $alley /Hmountain bree'e
• .griculture –
frost bite" chill inhabitation in the$alley
• +uring dayCalley bree'e
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 128/174
+uring daytime4 top
gets warmerthan $alley/ 19" $alley/ ,9
• So windmo$es from$alley to the
top /H$alleybree'e
y
<ind system of the world
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 129/174
y
1and bree'es
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 130/174
•
+i=erentialcooling of landand water
• +uring night4
• land cooler /,9"
• water /19
• <ind mo$e land
to water /H landbree'e
Sea-bree'e
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 131/174
• +uring day time4• land gets warmer
/H19 " water /,9
•
<ind mo$e fromwater to land /Hsea bree'e
9ressure belts of theworld
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 132/174
world
9lanetary wind systemCariable winds
Seasonal" local winds)ountain- $alley bree'e
1and-sea bree'e
• .roundpper tropospheric winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 133/174
.roundtropopause" there
is only onegradient
• <ind accumulatedabo$e euatorand rari(edatmosphere abo$epoles
•
,9 at the euatorand 19 at thepoles
pp p p
%eo-strophic winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 134/174
• strong coriolis
force attropopause
• ecause friction isless - high speed -
stronger thecoriolis force
• So the deectionis J0 degree
• Such winds calledgeo-strophicwinds
p
<esterlies winds
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 135/174
• The upper
tropospheric winds 6geo-strophic
winds blowfrom westto east atthe $eryhigh speed
li3ossby wa$es
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 136/174
• <esterlies at
poles – tomaintain theangularmomentum- they
meander /H3ossby wa$es
• 3ossby wa$es donot meander
consistently" butfollow a cycle /Index cycle
y
Vet streams
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 137/174
•
In westerlies"there are strong"narrow bands ofhigh speed wind
/H Vet stream• Speed of Vet
stream00>mph
V
Vet streams location
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 138/174
• There are
situated at themargins ofmeridional cells
•
F permanent Vet streams4 29olar Vet and 2Sub-Tropical
<esterly VetST<V
V
2emporar# 1et Vet streams
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 139/174
'ermanent 1et stream
2emporar# 1etstream
• Vet stream Vet streams
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 140/174
Vet streamembedded in
westerlies3ossby wa$es8at highlatitude" causepressure$ariability
• ThatGs why
they are calledtra$ellingdepression
Vet Stream – tra$elling depressions
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 141/174
<eather of )id and high latitude
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 142/174
• <eather of higher latitude is more complexthan weather of euatorial or tropical regions
• ecause tropical and euatorial region areheat surplus region– thermal reasons play
the dominant role@• ut higher latitude are heat de(cit region –
dynamic reasons play dominant role
•
These include – localised ; upper-tropospheric circulations 3ossby wa$es" Vetstreams" temperate cyclones8
• 1arge extensi$e body.ir mass
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 143/174
• 1arge extensi$e bodyof air-mass
A000s>m8• ,eight upto
Tropopause
• .t particular height"
one air mass will ha$euniform temperatureand moisture across itswidth
• .irmasses can bedi=erentiate accordingto their temperatureand moisture content
• .ir mass acuired.ir mass
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 144/174
• .ir mass acuiredproperties fromthe source regions– land" marine"polar" arctic"
.ntarctic / gi$ethem identity@ :x@m9" cT
• :xtensi$e
homogeneoussurface ; longerstay ,98
.ir masses
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 145/174
•.ir masses do notstay at theirsource regionsfore$er" they
mo$e out@ <hilemo$ing they cameacross other airmasses@
*ront
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 146/174
• The relati$edi=erence betweentemperature andmoisture decide
their interactionwith one another
• The border6
meeting region ofthe two air-mass/H *ront
• If cold air mass!old front
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 147/174
If cold air massmo$e faster than
the other than it willlift the warmer oneupward /H coldfront
• the slope will besteep / there willbe sudden up-liftment of the warm
air / cumulonimbusclouds /frontalrainfall
• If warmer air<arm front
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 148/174
• If warmer airmass is moreacti$e than coldfront /H warmfront
•
slope will begentler / therewonGt be suddenup-liftment of
warm air /uniformprolonged rain –dri''le
*ronts
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 149/174
*rontal cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 150/174
• .lso called asextra-tropicalcyclone"tra$elling
depressions"cold-corecyclone"wa$e
cyclones
)eaning of cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 151/174
A8 Intense 19 system
28 .ir con$erges towards thecentre
8 !losed isobarsF8 In #orthern hemisphere
con$ergence – anti-cloc>wise
Isobar
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 152/174
(ormal isobar
Closed isobar
!onditions for 19
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 153/174
2hermall# induced
•
ecause of hightemperature
• :x@ 19 at euator
• !on$ectional rainfall
at euator
• pliftment of warm air
• :x@ 19 at sub-polar 19belt
• *rontal rainfall
D#namicall# induced
• )o$ement of+e$elopment of *rontal cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 154/174
• )o$ement of
airmasses fromtheir source region
• The warm andcold air mass face
each other• . front is created
between them
•
!alled Stationaryfront
*ormati$e stage of frontal cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 155/174
3ocation of air
masses
Circular movement
• !old air mass+e$elopment of *rontal cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 156/174
!old air mass
pushed the warmair mass
• *orced upliftmentof warm air mass
at the cold front/19
• Two cold air masscon$ergence –circular due tocoriolis force
)ature stage
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 157/174
Interaction of air
masses
3' . closed isobars
• &ne cold air mass&ccluded front
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 158/174
&ne cold air massclimb o$er othercold air mass–warmfront is destroyed
• !alled occluded
front• 3apid change in
temperature andpressure
• nstable weatherconditions
• *rontolysis –t
+issipation of frontal cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 159/174
no great
temperaturedi=erencebetween twocold air
masses –frontdissipated –19 reduced –cyclonedissipated
Stationaryfront
+ront
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 160/174
&ccludedfront
+rontol#sis
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 161/174
9ath of the temperate cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 162/174
• .lways west toeast direction
• ecause inuence
of the wetserlies• %radual
mo$ement-9redictable
weather
+istribution of temperate cyclones
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 163/174
,urricane –#@ Tropical cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 164/174
,urricane #@.merica
Typhoon - !hina
• 1ate summer
• Increased sea
surfacetemperature / 19
• !on$ergence of airaround 19 'one
• 3ising moist wet8air /H absoluteinstability
Tropical cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 165/174
•!loud formation/more and moremoisture – latentheat of e$aporation
/H cumulo nimbuscloud /H cyclone
• !oriolis forceinduce spiralmo$ement of air
• Intensi(cation of
)ature Tropical cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 166/174
Intensi(cation of
19• !on$erging air
near watersurface
• !irculating airrises abo$ecoriolis force8
•
+i$erging air atthe top ofcyclone
• .t the centre of the
:ye of the tropical cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 167/174
• .t the centre of the
cyclone – QeyeG of thetropical cyclone@
• It is a pressuredefect@ ecause" atQeyeG a narrow
stream of winddescend / is ,9 atQeyeG
• .t the eye" there is
clear s>y@• eyond eye wall –
extreme low pressure
9roperties of tropical cyclones
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 168/174
• )o$e swiftly
• It is fuelled bymoisture – sowhen cyclone is
cut-o= from seaand mo$etowards land – itstarts
wea>ening
+istribution of tropical cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 169/174
2 i l l
comparison
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 170/174
2emperate c#clone
• 0-F0 degree latitude
• +ynamically induced
•
+ue to frontalinteraction
• *ormed o$er largearea
•
)o$e west to east• %radual mo$ement –
predictable
• D-20 degree latitude
• Thermally induced
• +ue to increasing SST
• Small area
• )o$e east to west
•
Swift mo$ement-diWcult to predict path
2ropical c#clone
2 i l l
comparison
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 171/174
2emperate c#clone
• <ind speed F0-50>mph
• 9ressure gradient JD0mb
• 9owerful on land
• .=ect mainland
• )ore time to dissipate
• <ind speed HA20>mph
• 9ressure gradientMDD0 mb
• <ea>ens on land
• .=ect only coastalareas
• ?uic>ly dissipate aftercoming on land
2ropical c#clone
?@ Tropical cyclones arelargely con(ned to
?uestion
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 172/174
)ains
20AF
g y
South !hina Sea" ay ofengal and %ulf of)exico@ <hyB A08
9S!
A8 Tropical
3eason for location of Tropical
cyclone
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 173/174
water
28 <arm oceancurrents
8 Increase SSTin late
summer
F8 Tropicalcyclonemo$e east towest
58 1andmass onwesterncoast
8/17/2019 geogra l5 2
http://slidepdf.com/reader/full/geogra-l5-2 174/174