HEAD
OUR CLIMATE
AND OUR IVEA THER
LIMATEis one of the greatestupsettersof
humanplansand activities.
It dictatesour
economy,what we wear,the kind of housewe
livein,thesortof foodwe eat,howhardwe work,and
evenwhenandwherewe spendour vacations.
Farmers
andindustrial
magnates
mustbowto it;allanimal
life,
frominsectto elephant,
livesanddiesunderitsrule.
C
OFFICE, MONTREAL, OCTOBER 1949
summer,
addedit to theircharts,
anddecided
thatwe
are wellon ourway to a newtypeof climatein the
countries
bordering
on theAtlantic
coast.
Summers,
theysay,aregetting
progressively
hotter
and longer;wintersare milder.But,theyhastento
add, our historicalrecordsgo back only a short
distance--merely
for secondson the clockof the
earth’sprogress.
Thepresenttrend,detected
in the
1880%"maybe justa shiverin the world’sweather,
butit mightalsobe theroadbackto a muchdifferent
climate."
Mankind has never known a "normal"climate.
Weof 1949areat thetailendof aniceage,living
ina
timefollowing
a periodof climatic
violence
as great
as anythe earthhasknown.Several
of theseperiods
canbe tracedin the earth’s
crust,and between
them
therehavebeenlongagesof genialclimatic
uniforWearerising
outof a coldperiod
thathaditsgreatmity,lookeduponby geologists
as "normal"
times. est depthabout1,500,000yearsago. Glaciersall
overthe worldare receding
rapidly;
the permanently
Climaterunsin cycles.Our oldestrocks,around frozensubsoilin northern
Canadais meltingslowly;
RainyLakein Western
Ontario,
revealgraveldeposit- shipscan now reachSpitsbergen,
northof Norway,
ed underphysical
conditions
notgreatly
different
from duringninemonthsof the yearinsteadof the three
thoseof today.
monthsof thirtyyearsago.Whenwe are entirely
out
of theIceAgetherewillbe forests
in theinterior
of
We areallfamiliar
withthedailycyclein thetem- Greenland
wheretheiceis now twomilesthick.
peratezones:a maximum
temperature
in earlyto midClimateand Food
afternoon
and a minimumshortlybeforesunrise.
The
annualrangeis alsofamiliar,
through
the variety
of
No otherearthly
forcecanso mouldcivilizations
as
temperature,rain, snow and wind that makes up
a changein climate.
Men are pushedforwardimpetuSpring,Summer,Autumnand Winter.
ouslyin someregions
andheldbackto a sluggish
pace
in others,
bothphysically
andmentally.
We thinkand
Nextin significance,
probably,
isthewidely-accept-actbecause
of theburning
of foodin ourtissues,
and
ed 11-year
cyclecorresponding
to thecycleof sunspot the speedof thisburningdependslargelyuponthe
frequency.
Recordskeptfor morethantwo centuries typeof our foodandexercise.
Exercise
stepsup the
show that sunspotswax and wane in number and
rate.If the temperature
and humidityaretoo high,
extenttwicein aboutevery23 yearson theaverage. our body temperaturerises quickly.We are soon
Sincethesunis thesourceof ourheatandthebasic prostrated.
So we learnto takeit easyin thetropics.
causeof ourweather
changes,
it is natural
enoughto
supposethatcyclesof weathershouldcorrespond
to
Availability
of food is important.
We have seen
suchchanges
in thesun’scondition,
although
thisis
algae,
a lowformof plantlife,thriving
in hotsprings
notyetproven.
at 200degrees;
thereareSiberian
Arcticplantswhose
root-systems
survive
short
periods
of 90 degrees
It is GettingWarmer
belowzero air temperature;
but most plantsgrow
One pointaboutwhichthereseemsto be general withina narrowrange.For eachdegreeof latitude
agreement
is thattheearth’s
surface
is getting
warmer. northof theEquator
andforeach400-foot
increase
in
Just a month ago ProfessorG. H. T. Kimble and
heightabovesea levelon thisNorthAmerican
contiProfessor
F. K. Hare,bothof McGillUniversity’s nent,the dateof floweringof plantsof the same
Department
of Geography,
tottedup thescoreforthis species
is retarded
4 days.
Weather and Health
Theweather,
whichis a fickleactorwithin
a changeablebutlesshastily
changing
climate,
hasmuchto do
with our health.Thereis an undoubted
connection
betweenkindsof weatherand prevalence
of thisor
that malady.Hay feverbelongsto Autumn;whatis
generally
called"lungtrouble"
is moreprevalent
in
Spring than in midsummer; cold damp weather
increases
the discomfort
of rheumatism.
A tropical
climate
favours
theorganisms
thatcausesomediseases
such as malaria and hookworm,and reduces our
resistance
to disease
ofallkinds.
Pepys,
theEnglish
diarywriterof the1660’s,
seems
to havebeenparticularly
susceptible,
as someamusing
extractsfromhis diarywill show;"Got a coldby
sittingtoo longwithmy headbarefor Mum to comb
and washmy ears.
Gota strange
coldin my head,
by flinging
offmy hatat a dinner
andsitting
withthe
wind on my neck ....Caughta coldthroughleaving
my waistcoatunbuttoned."Out of all thesedire
experiences
he evolved
a preventive
devicewhichwill
amaze many medicoesand laymen:"Myselfin good
health,
butmightyaptto takecold,so thatthishot
weather
I am fainto weara clothbeforemy stomach."
Heatwaves,too,bringtheirperilsto Canadians.
We are the kindof animalthatcannotliveif our
in subduingour innerfires
bodytemperature
variestoomuchaboveor below98.6 We may havedifficulty
quickly
enough
to
meet
the
suddendifficulty
in heat
degreesFahrenheit.
Through
extremes
of temperature,
loss. Thousandsof us may developheatstrokeof
from the lowestCanadianrecord(81 belowzero)
greateror lesserseriousness
at temperatures
that
to the highest(115)the bodystrivesto maintain
residents
in theleast.We
constant
temperature
throughitsown heat-regulatingwouldnotbothertropical
are inclinedto eat too muchcarbohydrate
(sugar,
machinery.
In coldweatherit speedsup the rateof
to thesun.
heatproduction,
contracts
itssurface
bloodvessels
and starchandfats)andthenexposeourselves
evenproduces
extracirculation
by shivering.
In hot Thismeansthatwe are raisingheatinsideand absorbing
it fromoutside
at thesametime.
weatherthe surfacebloodvesselsare enlargedto
carryheatmorequickly
fromtheinsideto theoutside, Canada’sClimate
andtheevaporation
of sweathasa cooling
effect.
Canada is in the North TemperateZone. That
In Canada’s
temperate
climate,
wherean energetic means,according
to onewit,a climatewhereyoucan
lifeis encouraged,
breakdown
diseases
causemedical stayin one spotand get frostbitein Januaryand
men theirgreatestworry.Diseasesaffectingthe
sunstroke
inJuly.
lungshavebeenfoundby thePrudential
LifeInsurance
Company
of America
to be prevalent
in Brazil,Ecuador
How truehe is maybe seenby theremarkable
table
and Colombia.In thosecountriesthereis a great at the bottomof thispage.Notethe lengthof the
contrastbetweenthe 95 to 110 degreestemperature recordsrangingfrom31 yearsto 105 years.In all
in the afternoonand the 50 degreesto whichthe
thistimethereis no stationwhichhas notrecorded
thermometer
fallsin highaltitudes
at night.Cana- at some time below-zerotemperatures,
and every
dianswho live in an indoorwinterclimateof 80
station
has
had
temperatures
of
95
or
over,
whilethe
degreesand dashout into 20 belowzeroto gossip annualaverages
runfrom17 degreesto 49.5.
on thestreetcornerare-to putit mildly-foolish.
As for the commoncold, there probablyis no
diseasethatdoctorsknowtheyknowlessaboutand
thateveryoneelsethinkshe knowsmoreabout.Some
peoplebelievea coldcomesfromlackof properfood
or drink;othersblametheirneighbours
or a draught.
Suchvarietyimposesa severediscipline
on both
bodiesand minds.To peopleaccustomedto more
equableclimesCanadawouldappeara roughschool.
It does turn out men and women whoseframesare
braced
foractivity.
Progressis a productof moderateadversity,
not
of easeandlangour,
andCanadians
arenot bornwith
silverspoonsin theirmouths.We havelearnedmore
thanto comein outof therain:we havedeveloped
a
constructive
energythathasgivenus homes,factories
andfarmssecondto thoseof no country
in theworld,
anda standard
of living
thatis theenvyof many.
relationbetweenthe two.It is possible,
saysDr.
Kimble,
to havedrought
as weUas rainwitha southerly wind, and heat waves have accompaniednorth
windson occasion.
It is air masses,
not winddirections,
thatarereally
significant.
When the differencein temperature
betweenthe
equatorial
regions
andthepolarregions
setsup largescalemovementsof air, they are modifiedby the
Mostof us ownan overcoat,
a raincoat,
rubbers,
an
of the earth,thusestablishing
a systemof
umbrella,
a bathing
suit,a muffler,
suntan
lotion,
cough rotation
windbeltsand beltsof calm.Thereare
syrup,
anda bottleof aspirin.
Some,in addition,
have alternating
fourmainbelts:
thedoldrums,
thehorselatitude
belts,
snow boots,ear muffs,parkas,mukluksand a sun
hat.Withthisequipment
we get alongverynicely. thetradewindbelts,andthebeltsof theprevailing
westerlies.
Air Conditioning
Theprevailing
westerlies
arenorthandsouthof the
NorthernCanadais, at certaintimesof year,an
horselatitude
belts.Theair tendsto movefromthe
almostperfectrefrigerator.
The RockyMountains
in
highpressure
of thehorselatitudes
tothelowpressure
thewestkeepcurrents
of newairfromflowing
easily of thepoles,
deflected
by theearth’s
rotation
so that
intothatregion.
Forweekstheairliesnearlystill. windsblowfromthesouthwest
in the northern
hemisThe sun risesforonlya shortperiod,andthusthe phereand fromthenorthwest
in the southern
hemiscoolinggroundand the frozenlakeschillthe air
phere.Thegreater
partof Canadaliesin thepathof
abovethem.A hugemassof uniformly
ice-cold,
dry, theprevailing
westerlies.
clearairstretches
fromtheRockies
to Labrador,
from
Our Water Supply
theprairies
to as farnorthasnorthgoes.Itis likea
glacierof air.The weathermen callit a massof
Whenair rises,it expandsandso coolsto a tempolarcontinental
air.
perature
lowerthanat the earth’s
surface.
Its water
thusforming
greatmassesof minute
Air waves,whichmay be 500 milesor 1,000miles vapourcondenses,
and sucha clusterof visiblemoistureis
fromcrestto crest,are aboutthe onlytravellers droplets,
a cloud.
thatcanstillmoveacrossnational
boundaries
without called
passports,
visasand permits.The polarair surges
Manya cloudlooksas if it hadbeenput together
southward
as faras theGulfof Mexico;tropical
air painstakingly
aftera year’swork of planningand
washesnorthward
to theedgeof theArcticor farther. fitting.
Thisis certainly
trueof thecumulus,
thick,
The actionunderlying
GeorgeStewart’s
novelStorm mountain-like
massesoftenseen on a summerday
wastheprogress
of a wavealongthispolarfront.
abouthalfa milefromthe ground.
Thecumulus
is the
mostmajestic
of clouds,
moving
in stately
deliberation,
Our Polar Front
withperfectly
formedand sharpoutlineswhichare
Today’sweatherscienceis basedon the ideathat yetas transitory
as a dream.
It is saidthatthegreat
changesin weatherare causedby conflictbetween painter,
Turner,
declared
therewereonlytwoaspects
greatmassesof warmand coldairalong,this"polar of naturehe wouldnot attemptto paint:thesnowof
front,"wherethe north-bound
warm air meetsthe
the highAlpsand a cumulus
cloud.
south-bound
coldair.
Cirrusclouds
arethin,feather-like
formations,
at a
Mr.A.J.Connor,
of theAirServices,
Meteorologicalheightof aboutthreeto tenmiles,composed
of minute
Division,
Department
of Transport,
wroteus an exicecrystals.
Stratus
clouds
areflatlayers
often
seennear
planation
of thisyear’sunusual
weather.
He said:
the horizonearlyin the day,at a heightof about
In Canadawe expect
in summerfrequent
incursions
of 800 feet.Nimbostratus
clouds,our familiar
rainor
polar
airinto
southern
districts.
These
serve
first,
tolift snowclouds,are dullgrey,withthinnerspotsthat
warmer
andmoister
airtolevels
where
precipitation
may
a slowly-moving
lightbehindthe veil.They
begin,
andsecondly,
tooccupy
southern
regions
fora day suggest
feetor a milehigh.
or twoofcooltemperatures
withlowhumidity.
Thisyear maybe a fewhundred
theincursions
ofcontinental
polar
airhavebeenrather
An inchof rainis theamountof precipitation
on a
feeble
incentral
Canada,
allowing
theusual
summery
flow
of warm,humidairfromthesouthto continue
largely levelmoisture-proof
surface
to thedepthof oneinch.
unchecked
forunusually
longperiods.
Rainfall
hastherewe say,forexample,
thatthetotalannualpreciforebeenscanty,
andthehumidity
oppressive
incentral When
pitation
at
Fredericton
is
42.80,thatmeansthereis
regions.
enoughprecipitation
on thesurface
whereit is measLastwinter,
major
outflows
ofpolar
airpreferred
tofollow uredto coverit,if levelandmoisture-proof,
toa depth
a pathalong,
orimmediately
east
of,theCordilleran
region,
As a rule,aboutteninchesof snowis
bringing
unusually
heavysnowsandan unusually
long of 42.8inches.
requiredto makeone inchof water.An inchof rain
winter
tothemostwesterly
portion
ofthecontinent.
is 113shorttonsof wateruponan acre.
Wind and Weather
Humidity
We have becomeaccustomed,since our earliest
Humidity
is justanother
wordformoisture
or dampdays,to associate
certain
windswithcertain
kindsof
ness,butwe meanfarmorethanthatwhenwe say"the
weather,
andit is surprising
the numberof timeswe
Thatmeansthe degreeof wetnessof the
areright.Yet,saytheexperts,
thereis no clear-cut humidity."
air.We may express
it in a percentage,
whichrepresentsthe amountof waterin theair relative
to the
amountwhichwouldbe presentweretheairsaturated
at the sametemperature.
A relativehumidityof 40
percentmeansthattheairholds40 percentof the
maximumamountof moisturewhichit couldholdat
thattemperature;
if theairis saturated,
therelative
humidity
is saidto be 100percent.
All the forecaster
pretendsto do is to say with
reasonable
assurance
thatif an existing
trendcontinues, certainthingswill happen.The speedof the
weathermovementmay change,hastening
or delaying
arrival
of thekindofweather
he forecasts.
Controlling
Weather
Duringrecentyearsmany localrains have been
induced
dropping
dryiceon rainclouds.
Mr.J. L.
Whenhigh humidityinterferes
with lossof heat Orr,of by
the
National
Research
Council
of
Canada
told
fromthebody,because
theairis already
so moistit
theUnitedNations
scientific
conference
in Augustof
cannottakeup allthemoisture
ourbodieswouldlike successful
experiments
in thiscountry.
Analysis
of the
to throw off, we are uncomfortable.
Then when a
results
showed
that
rain
or
snow
reached
the
ground
humidspellis brokenby a showerour drowsiness on24 percentof alltheCanadian
trials.
In theapplied
may vanish.
experiments
on selectedcloudsrainor snowreached
It wouldbe usefulto havean absolute
scaleof com- thegroundon 43 percentof theattempts.
fortin relation
to temperature
andhumidity.
(Scientistshaveestablished
68 degreesas suitingmost
Mr.Orradded:"Fromthescientific
standpoint,
the
officeworkers,and say the humidityshouldbe 60
results
achieved
arenoteworthy
andtheability
to alter
per cent.)But the makingof sucha chartrunsup
thestructure
of thegreatmajority
ofclouds,
to produce
against
thedifficulty
thatthereisa marked
difference precipitation
from many clouds,and even, under
in what individualscall comfortable.The work
certain
conditions
to generate
clouds,
is remarkable."
in manyofficesand factories
wouldbe improvedif
temperatures
were adaptedto the comfortof the
The advancealreadymadein knowledge
and practnormalwellpeople,andlet the complaining
few put ice
indicates
that
it
may
be
possible
to
put
rain-making
on moreor lessclothes.
on a firmbasisshortly.
At a timewhenrainis badly
neededin some crop-growingor electricpowerWeatherForecasting
producing
partof Canada,
thefinancial
returns
could
TheMeteorological
Bureaudoesnot issueforecasts beof significant
value.
But,saysMr.Connor
ina letter
primarilyfor the convenienceof peoplewho are
on the work of Canada’sMeteorological
Division,
thinkingof goingon picnics.
Weatherforecasts
are
"ifwe everget weathercontrolon thisearth,wars
neededby airmen,sailors,farmers,shippersof
willfollow,
instigated
by thosewhowishto havefull
perishable
goods,forestrangersand businessmen.
controlfor theirown countryalone."Thenhe adds
The effectsof weatheron the cashregistercan be
facetiously:
"Domestically,
thenational
weather
conmightyimportant.
trollers
willneeda battalion
of bodyguards!"
Forecasting
in Canadais doneby the Department
of
Transport
as a publicservice,
and ourmeteorological Whatwe shouldlike,of course,is moreorderliness
service
rankswiththebestin theworld.Mainbureaus in the weather.Thereshouldbe some snowand ice
so thatwe arewilling
to workhardenough
are in Vancouver,Edmonton,Winnipeg,Toronto, in winter,
to enjoya littleleisurewhenspringcomes.Spring
Montreal,Halifaxand Gander,servedby many rewithflowers
andbeesand
portingstationsoverthe continent.
Whenthe main shouldbe a poet’sdelight,
mating
birds,
and
it
should
last
two
months.
Summer
station
hasin handallreports
fromitsowndistrict,
fromthe otherdistricts,
from the UnitedStates, shouldbe warmenoughto thawthe frostout of our
Alaska,Mexico,fromCanada’selevenstationsnorth bones,giveus the righttintof tan,and growour
gardenvegetables
and gladiolus
to the rightsize,
of the ArcticCircle,fromEuropeand fromshipsat
texture
and
shade.
Autumn
should
be longenoughfor
sea,themeteorologist
has a goodideaof whatconus to restaftera strenuous
summer,
colourful
enough
ditionsarelikelyto be duringat leastthe next24
to
gratify
our
aesthetic
sense,
and
just
cool
enough
to
hours.He is helpedby twice-daily
soundings
of the
easeus gently
intowinter.
upperair.
Prediction
is madedifficult
by thefactthatso many
factors
mustbe keptin mindandweighed
at onetime.
Thepublicdemands
thata forecast
shallbe expressed
as nearlyas possible
in oneword:clear,
fair,cloudy,
rain.Thisdoesnotallowa fairexercise
of theforecaster’s
skill,becauseto describe
whatwilllikely
happenin the next 24 or 36 hourswouldrequirea
paragraph
at least.Therecan be greatdifferences
withinsmallareas:not longago therewas rainon
St.JamesStreetin Montreal
andnoneon CraigStreet,
onlya blockaway.No matterwhattheforecast
said,
people
on oneof thesestreets
wouldthinktheweatherman was wrong--or,as they would likely say,
"wrongagain."
Everyseasonshoulddignifyitselfby comingin on
the properdate.Thiswouldenableus to make,sell
and buy clothesin a reasonably
stableway,and to
knowwhetherit is necessary
to lay in anotherton
ofcoal.
Tilltheseimprovements
can be made,theclothing
manufacturer,
the department
store,the coaldealer
and the consumermust plug alongwith the aid of
Almanacs,the Meteorological
Bureauand theirown
amateur
efforts
at forecasting.
Perhaps
itis better
so,
becauseif our weatheridealswere achievedwhat
shouldwe grumbleabout?
PRINTED IN CANADA
by The RoyalBankof Canada