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DIVISION OF BUILDING RESEARCH
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C a n a d a L s c o v e r e d b y s n o w f o r a p o r t i o n o f e v e r y y e a r . T h l s s l m p l e f a c t h a s m a d e S n o w s u c h a c o r o m o n - p l a c e i n a t e r l a l t o C a n a d i a n s t h a t t h e n e e d f o r l t s s c l e n t l f i c s t u d y i s n o b g e n e r a l l y a p t r r r e c i a t e d . t i v e n t h e s i m p l e s t s t u d y o f t h e e f f e c t s o f s n o w o n t h e C a n a d l a n e c o n o m y r q u i t e a p a r t f r o m t h e c o r r e s p o n d l n g e c o n o m l e a s p e c t s o f _ 1 c e p r o b -I b m s , w 1 1 1 s e r v e t o s h o w t h a t , a l t h o u g h l o n g lgglected, snow 1ft a materlal about whlch Canadians shouJd know a g o o d d e a l . T h e N a t i o n a l R e s e a r c h c o u n c l l - h a s a p p r e c l a t e d t h e L m p o r t a n c e o f S n o w a n d l c e f o r g o m e t l m e . $ t u d l e s l n t h l s u n u s u a l f l e I d o f r e s e a r c h h a v e b e e n c a r r l e d o u t w i t h l n t h e C o u n c i l s l n c e 1 9 5 5 , I n i t l a l s t u d l e s w e r e r e l a t e d t o t h e p r o b l e u n s o f a l r c r a f t s k l s . T h e y s h o w e d q u i l e c l e a r t y t h a t e v e n t h l s p r o b l e m c o u l d n o t p r o p e r l y b e d e a l t w l t t t w i t h o u t a d e t a i l e d s t u d y o f t h e p r o i r e r t l e s o f s n o w , t h e m a t e r i a l o n w h l c h t } l e s k L s h a d t o o p e r a t e " T h l s l e d t o t h e l m p o r t a n t s t u d i e s o f s n o w m e a g u r e m e n t a n d s n o w c l a s s l f l c a t i o n c a r r l e d o u t b y M r . G e o r g e J " h I e i n , o f t h e L i i v l s l o n o f i V i e c h a n l c a l E n g i n e e r l n g . T h e k n o w l e d g e g a i n e d f r o m t h e s e p e a e e t l m e s t u d L e s was applied to a number of wartime problems durlng the y e a r s f g + O 1 9 4 5 o A s s l s t a n c e w a s g l v e n t h r o u g h t h e ^ D 1 v ! -i -i o n o f M e c h a n t c a l E n g l n e e r l n g t o t h e d e v e l o p m e n t o f s p e c l a l o v e r - s n o w v e h i c l e s " M e u b e r s o f t h e s t a f f o f t h e D i v l s l o n o f P h y s l c s a s s i s t e d w l t h i c e s t u d l e s 1 n c o n n e c t i o n w l t h t h e f a m o u i r r H a b b a k u k t t p " o j e c t . L a t e l n t h e v { a r , t h e C o u n e l l f o r m e d a n A s s o c l - a t e C o m r n i t t o e o n S o 1 1 a n d S n o w I v l e c h a n l c s w h l c h f o s t e r e d t h e f u n t h e r d e v e l o p m e n t o f t h e s n o w s t u d l e s w i t h s p e c i a l r e f e r e n c e t o t h e p e r f o r m a n c e o f t r a c k e d v e h i c l e s . T h e s t u d l e s o f t h l s c o m n l t t e e d e m o n s t r a t e d a g a l n t h e l m p o r t a n c e o f f u n d a m e n t a l r e s e a n c h l n t o t h e p r o p e r t l e s o f m o w a n d l c e " A s a r e s u l t n t h e w r l t e r a n d M a i o s i v i . G ' B e k k e r ( o f t h e D l r e c t o r a t e o f V e h l c J e D e v e l o p m e n t o f t h e C a n a d l a n A r m y ) v l s l t e d S w i t z e r l a n d ! n t h e s p r l n S _ o f 1 9 4 6 " I t h a d b e e n l o u n d t h a t s w l t z e r l . s r d w a s p r a c t i c a l l y t h e only country 1n whlch any appreclable amount of fundamental
snoil and lc-e research work had been carrled out. The work whlch w a s s e e n l n p r o g r e s s a t t h e $ w l s s I n s t l t u t e f o r S n o t u
R e s e a r c b a n d A v a l a n c h e P n e v e n t l o n n e a r D a v o s c o n f l r m e d m o s t d e f l n l t e l y t h e l m p n e s s l o n w h l c h h a d b e e n f o r m l n g L n C a n a d a a s t o t h e n e e d f c n s l m l L a r w o r k l n t h e D o m l n l o n .
I n ! 9 4 1 t h e C o u n c l l s e t u p a n e w D i v i s l o n o f B u i l d i n g R e s e a r c h . I b w a s e l e a r t h a t s o m e o f t h e b a s l c p r o b i e m s t o b e s t u d l e d b y t h l s D l v i s i o n w o u l d b e r e l a t e d t o s n o w a n d i c e " T h e n e w D l v i s i o n h a s , t h e r e f o r e , c o - o p e r a t e d c l o s e l y w l t h t h e D l v i s i o n o f I V l e e h a n i c a l E n g l n e e r l n g l n t h e d e v e l o p m e n t o f p l a n s f o r s n o w a n d i c e r e s e a r c h w o r k . L i a i s o n w i t h S w l s s w o r k e r s h a s b e e n m a i n t a i n e d a n d d e v e l o p e d . I n 1 9 4 8 t h e N a t i o n a l R e s e a r c h C o u n c l l a p p r o a c h e d S w i s s a u t h o r l t l e s w l t h t h e r e q u e s t t h a t t h e y a s s i s t t h e D i v l s i o n o f B u l l d i n g R e s e a r c h t o l L n d a y o u n g S w l s s s c i e n t i s t w h o c o u l d b e 6 ; i n w o r k i n C s n a d a 1 n t h l s s p e c l a l f l e l d " T h e a n s w e r t o t h l s r e q u e s t w a s s u r p r i s i n g a n d e n c o u r a g i n g " f n s t e a d o f h a v l n g t h e n a m e o f a y o u n g m a n s u g g e s t e d t o t h e m , t h e C o u n c i l w e r e o f f e r e d t h e s e r v i c e s o f D r . f u l a r c e l - d e Q u e r v a i n f o r a p e r i o d o f o n e y e a r , i n o r d e r t o a s s i s t w l t h t h e s t a r t o f G a n a d l a n s n o w a n d l c e r e s e a r c h . D r . d e Quervaln ls now the Direetor o f t h e S w i - s s S n o w R e s e a r c k r I n s t i t u t e . A t t h e t l m e o f h i s v l s l t u h e w a s t h e c h i e f s c i e n t l s t o n t h e I n s t l t u t e f s s t a f f o H e l s a s c l e n t l s t o f n o t e a n d h l s k n o w l e d g e o f s n o w a n d i c e r e s e a r c h w o r k i s p r o b a b l y u n r i v a l l e d . A c c o r d l n g 1 y , t h e $ w i s s o f f e r w a s g l a d J y accepted and Dr. de Quervain spent one year as a g u e s t m e m b e r o f t h e s t a f f o f t h e D l v l s i o n o f B u i l d l n g R e s e a r c h ,
T h i s R e p o r t s u m m a r i z e s t h e s t u d i e s w h i c h D r . d e Quervain m a d e l - n t h e U n l t e d S t a t e s a n d C a n a d a during his year of servlce
w i t h t h e C o u n c i l . t s a s e d u p o n i t , D r . d e Quervaln has prepared a n u m b e r o f s p e c l f i c r e c o m m e n d a t i o n s f o r a b r o a d p r o g r a m f o r s n o w a n d i . c e r e s e a r c h w o r k i n C a n a d a ; t h e s e a r e belng sribmltted t o t h e N a t l o n a l R e s e a r c h C o u n c l l " T h e R e p o r t m a y b e l e f t t o s p e a k f o r l t s e l f s i n e e i t d e m o n s t r a t e s v l v l d l y t h e v a l u e o f D r . d e Quervalnls stay ln Canada. One detail m a y , h o w e v e r o b e m e n t t o n e d . A l t h o u g h D r . d e Quervain made hls origlnat n o t e s l n h l s n a t l v e t o n g u e , h e w r o t e h l s c o m p l e t e d R e p o r t i n
E n g l l s t r " T h i s , 1 r r l t s e l f , w a s a r e m a r k a b l e f e a t o T h e R e p o r t u a s n o w r e p r o d u e e d , l s e x a c t l y a s D r . d e Quervain wrote lt
( a p a r t only from edi-torial c h a n g e s ) " T h e h a p p f l d l o m s a n d t h e o c c a s i o n a l h u m o r o u s r e f e n e n c e a r e a t r r r e , i - e f l e c t i o n o f t h e d e l i g h t f \ r l p e r s o n a l l t y o f t h e a u t h o r o ,
T h e R e p o r t p o i n t s t o t h e w a y l n w h l c t r r e s e a r c h l n t o t h e p r o b l e m s assoclated wlth sno$r and lee should be pur..sued if
C a n a d . a i s t o g i v e a p p r o p r i a t e a t t e n t l o n t o t h e s e e p r m o n - p l - a e e m a t e r i a l s w h l c L r a r e o f s u c h e c o n o m l c l m p o r t a n c e " I t p r o v i d e s a u s e f u l f o u n d a t l o n f o r f u r t h e r s t u d l e s , a f o u n d a t i o n o f s p e c l a l v a l u e l n t h a t i t l n c o r p o r a t e s t h e r e s u l . t s o f t e n y e a r s s o f p l o n e e r i n g e x p e r l e n e e l n $ w i t z e r l a n d l n t h i , r i s p e c l a l f l e l d o f w o r k , I t m a y b e t h o u g h t b h a t b e c a u s e o f tfre difference l n s l z e b e t w e e n C a n a d a a n d S w i t z e r l a n d , t h e p r o b l e m s o f s n o w a n d l c e r e s e a r c h . l n t h e t w o c o u n t r l e s w o u l - d b e d i s s i m l f a r " P o s s i b l y t h e m o s t l m p o r t a n t r e s u l t o f D r " d e Q u e r v a i n t s v i s i t w a s t h e d e m o n s t r a t l o n t h a t t h e b a s l c p r o b l e m s o f t h e t w o c o u n t r i . e s a r e
I f a n y r e a d e r s o f t h i s R e p o r t a r e i n d o u b t a s t o t h e s l g n i f i c a n c e o f s n o w a n c i i c e l n t h e C a n a d i a n e c o n o m y e r e f e r e n c e m a y u s e f u l l y b e g l v e n t o t h e f a c t t h a t B r i t l s h C o l u m b i a w a s e f f e c t i v e l y s e p a r a t e d b y s n o w s l i d e s f r o m t h e r e s t o f C a n a d a f o r s o m e d a y s d r : r l n g t h e w i n t e r s o f b o t h 1 9 4 8 - 4 9 a n d 1 9 4 9 - 5 0 . l T h i - I e i t l - s n o t s u g g e s t e d t h a t s n o w a n d i c e r e s e a r c k r c o u l d h a v e p r e v e n t e d t h e s e d i s a s t r c u s d i s -r u p t i o n s o f r o a d a n d r a 1 l a e r v i c e s , t h e y c o u l d c e r t a l n l y h a v e c o n t r l b u t e d t o t h e p r e d l c t l - o n o f s o m e o f t h e a v a l a n e h e s w h l c h c a u s e d s u c h s e r l o u s d a m a g e a n d p r : o b a b l y h a v e m a d e s o m e c o n t r l o u t i o n ' t o w a r d s t h e w o r k w h l c h h a d t o b e d o n e 1 n c l e a r l n g r l n e s o f c o r n m u n l c a t i o n s . I t ls estimated that the a n n u a l c o s t o f s n o w c l e o r l n g a l o n e l n C a n a d a b y r a i l w a y s n h l g h w a y d e p a r t m e n t s , a n C c l t i e s , l s a t l e a s t t w e n i y m l l l l o n d o l - 1 a r s e a f i g u r e w h i c h c a n b e l e f t t o s p e a k f ' o r i t s e l - f " C o r r e s p o n d i n g l y , t h e c o s t o f t h e e x t r a c o n c r e t e b e i n g u s e d L n C a n a d l a n d a m s n o w u n d e r c o n s t r u c t l o n n e c e s s a r y t o r e s i s t t h e c a l c u L a t e d p r e s s u r e d u e t o l c e m u s t b e a s l m i l a r l y v a s t a m o u n t , d e p e n d e n t u p o n a s s u m p t l o n s w h i c h i c e r e s e a r c b r a l o n e c a n s u b s t a n t i a t e o r c o r r e c t . A l l s u c h p r a c t i c a l p r o b l e m s c o n n e c t e d w l t , L r s n o w and i c e a r e l l n k e d b y t h e b a s l c n e c e s s l t y f o r a c c u r a t e k n o w l e d g e o f t h e f u n d a m e n t a l p h y s i c a l a n d m e c h a n i c a l p r o p e r t i e s o f t h e m a t e r l a l 1 n q u e s t i o n - w a t e r , l n i t s s e v e r a l f r o z e n f o r m s o T h i s R e p o r t m a k e s e i e a r t h l s - f u n d a m e n t a l l n t e r - r e l a t i o n " I t l s h o p e d t h a t i t m a y a s s i s t l n t h e f u r t h e r d e v e l o p m e n t o f C a n a d l a n w o r k i n t h l s f u n p o r t a n t f i e L d o f r e s e a r c h o l t c o n -s t l t u t e -s a f u r t h e r v a l u a b l e l i n k b e t w e e n S w i s s a n d G a n a d l a n s n o w a n d i c e w o r k , L h e c l o s e a s s o c l a t l o n o f w h i c h m a y c o n -f i d e n t l y b e e x p e c t e d l o r € t o c o n t l n u e . F e b r u a r y , 1 9 5 0 e D i v i s i o n o f B u l l d i n g R e s e a r e t r
CONTENTS
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IT. SNOili AND ICE PROBLEMS IN CANADA AND THE U. S" AO A O I N T R O D U C T I O N
BU TIIE SNOIY AND ICE STTUATION IN CANADA T h e S n o w S l t u a t l o n
T h e I e e S l t u a t l o n
PARTICULAR SNOI,Ni AND ICE PROBLE&IS H y d r o l o g i c a l A s p e c t s o f S n o w
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( c ( e J A r t i f i c t a l ( f ) C o n c l u s i o n avalanche s r e l e a s e o f a v a l a n c h e s ) o S+ory Clearlng ( a ) S n o w c l e a r l n g o n h l g h w a y s ( U t S n o w c l e a r i n g l n c l [ l e s ( c ) S n o w c l e a r l - n g o n a i - n p o r t s ( O l S n o w c l e a r t n g o n p r i v a t e g r o u n d ( u I Snow cleanlng on railway tracks ( f l S n o w c l e a r l n f b y h e a ta p p l i c a t l o n S n o w C o m p a c t i o n
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( c ) A d h e s l o n o f 1 c e
( d ) Bearlng eapaclty of lce 9. Iqlng from tkre Atmosphene
( a ) I c l n g o n a l n c r a f t ( b ) I c l n g o f o b J e c t s o n t h e g n o u n d P e r m a f r o s t V a r l o u s ! " ) S n o w a n d f l r e f l g h t l n g ( b ) S n o w a s a waten source ( " ) Chemical compounds 1n snow ( d ) Snow and wlnier sports
AND ICE RESEARCH
I n s t l t u t l o n s f o n S n o w and lee Research l n Varlous Cor,mtries ( a ) A u s t n l a ( b ) C a n e d a ( c ) E n g l a n d ( d ) F r a n c e ( j ) U n l t e d S t a t e s ( k ) u . s o s o R o
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Appendlx B. Fonns A and B; Forms Ir2 and 3 of SRS and Chart l Appendlx C" Sunrmany of a Tnlp to Vlslt Snow and Ice Research
f n s t l t u t t o n s l n C a n a d a and the Untted S t a t e s - D o C o P e a r c e
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Taken near Sunshlne Lodge
Snow Proflle Taken at the Upper Columbla S n o w L a b o n a t o r y , G l a c l e n P a r k ,
M o n t a n a , ( 4 8 5 0 i e e t ) S n o w P n o f i l e s a t C h u r c h l i l
Map of Snow Surveys ln Canada
A v a l a n c h e S l t u a t l o n l n t h e I 1 1 e c 1 l 1 e w a e t V a 1 1 e y ( C t a c i e r , B " C " ) f c e C o n d l t l o n s N e a r O t t a w a -Jlst December, 19.l+8 A c c l d . e n t C a u s e d b y I c e C o n d l t l o n s o n H l g l r w a y N o . 1 7 N e g r M o n t r e a l , l l s t D e e e m b e r " 1 9 4 8 t 2 13
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3 0
3 1
3 2
3 3
3l+
2 2
2 3
z4
25
z6
T l t l eHeathen Lodge , UIt o Reve l-stoke e B oC o Snow Formatlon on a Tree ldear
G l a c i e n , B n C .
A v a l a n c h e S l o p e s N e a n G l a c l e r e B o C " Banff from Ivlt " Norquay Skl Llf t S n o w D e p o s l t l n a t r t i o o d e d A r e a N e a n
F o n t C h u r c h l l l o & i a n l t o b a
Drlfted. Snow in the Open at Font C h u r c h l 1 1 , M a n i t o b a M o d e l T e s t l n S n o w D r l f t , A e r o d r o m e t F o r t C h r . r r c h l 1 1 , Manitoba F l s s u n e 1 n t h e J c e o f i i u d s o n B a y N e a r C h u r c h l l 1 E s k l m o R e p a l n l n g t h e R u n n e r s o f a S l e l g h , F o r t C h u r c h l l l A l r c r a f t S k i s , F o r t C h u r - c h l 1 1 S n o v v m o b l l e M - 7 , S o d a S p : : l n g s , C a l " T u c k e n $ n o * c a t , S l s k y i o u P a s s , O n e g o n S n o w m o b l l e n B o m b a n d l e r n , S u n s h l n e L o d g e , B a n f f D e t a l l o f T n a c k s , t t B o m b a r d l - e n n I c e B l a s t l n g o n R i d e a u R l v e r , O t t a w a , . . c p r e p a r r a t l o n o f l c e b y c u t t i n g groove s . . . . t h e b l a s t A C h a n n e l o f C l e a n W a t e n l s O p e n e d P a r t o f t h e D r a l n a g e B a s l n o f t h e C e n t n a l S l e r r a S n o w L a b o r a t o r y C e n t r a l S l e r r a S n o w L a b o n a t o r y S t n e a m G a u g e ( P a n s h a l l F l u m e ) , C e n t r a L S l e n r a S n o w L a b o r a t o r y
35
36
37
38
3 9
Flsune No.
dL--4o
41
1+z
h:
!4
l+5
I+6
l+l
l+8
L I S T O F T L L U S T R A T I O N S (C O N t I d ) T l t l e V a n l o u s P r e c l p l t a t l o n G a u g e s , C e n t r a l Slenna Snow LaboratoryE p p l e y P y r h e l l o m e t e r , C e n t r a l S i e r r a Snow Labonatory
Anemometen, Central Slerna Snow Labonatony
Pant of the Dnal nage Basl-n of the Upper Columbla Snow Laboratory, Srxnmlt, Montana
Uppen Columbla Snow Labonatony
M t . WashS.ngton, N . Hu, fnom GIen
Lodge
Mount Washington Observatory
Snow Testlng wlth the Cone Penetnoneter", (Rammonsonde), Sunshlne Lodge
D . C" Peance Testlng Sn*ow w l t h t h e Hand Penetnometer, Sunshlne Lodge
by IWancel R. de Quervaln A . I N T R O D U C T ] O N A t t h e c o n f e r e n c e o f t h e I n t e r n a t l o n a l U n j . o n o f G e o d e s y a n d G e o p k r y s l c s h e l d i n 0 s 1 o l n A u g u s t , 1 9 4 8 , i v l r " R " F " L e g g e t s t , a t e A l n h l s p r e s e n t a t l o n e n t i t l e d " C a n a d i a n I n t e r e s t l n - S n o w a n d l c e R e s e a r c h t r , t h a t l n t h e n e a r f u t u r e C a n a d a m a y b e f o u n d . a m o n g t h e l e a d l n g c o u n t r l e s l n s n o w a n d i c e r e b e a n c h " T h i s s t a t e m e n t r u a s n o t m a d e f o r n a t i o n a l a m b i t l o n " I t i s b a s e d o n t h e a b s o l u b e n e e d o f t h e c o u n t r y t o m a n a g e l t s s n o v r r a n d 1 c e p r o b l e m s . E x t r a p o l a t l n g t h e p r e s e n t d e v e l o p m e n t o f C a n a d a , w e e x p e c t t h e p o p u l a t l o n t o l n c r e a s e i n t h e a r e a s a l r e a d y i e t t l e d a n d n e w a r e a s w 1 1 1 b e d e v e J - o p e d i n t h e m o u n t a i n s a n d , a b o v e a l l , t o w a r d s t h e n o r t h " T h e s e n h o w e v e r , a r e a r e a s w h e r e s n o w a n d i - c e l a s t l o n g e r a n d a r e m e t w i t h l n b l g g e r q u a n t l t l e s t h a n i n t h e s e t t l e d z o n e s " T k r u s , w l t h a d v a n c l n g c l v l l l z a t l o n , t h e t r o u b l e s c a u s e d b y s n o w a n d l c e w l l } i n c r e a s e . I n a d o i t l o n n i h e r n o r e t h e ' t e c h n l q u e l s r e f i n e d , t h e r n o r e t h e c l v i l l z a t l o n l s s e n s i -t l v e i o -t h e l n f l u e n c b o f t h e c l l m a t e e I n e . t o c o l d a n d t D s n o w a n d l c e . T h e g e n e r a l s c o p o o f t h e s n o w a n d l c e p r o b l e m s o f C a n a d a l s o u t l l n e d v e r y f u l l y i n L e g g e i t s r e p o r t . T h l s p r e s e n t r e p o r t h a s t o g o a s t e p f r - r t h e r . V f e s h a l 1 t r y t o a n a l y s e t h e p h e n o m e n a a n d t o s u g g e s t l n w h a t d l r e c t l o n r e s e a r c h w o r k c o u l d b e d o n e t o o v e r c o m e t h e p e n d l n g p r o b l e m s ' F l r s t , 1 t h a s ! o b e e x p l a i . n e d b r l e f l y h o w t h e w r i t e r o f t h i s r e f o r t w a s c t r a r g e d w i t h t k r l s t a s k . F r o m t h i s l t m a y b e s e e n l n w h a t w a y h e e v e n t u a l l y c a n b e e x p e c t e d t o h e l p " I n s p r i n g , 1 9 4 6 , M r . J t . F ' n L e g g e t a n d i l i a j o r i / 1 . G o B e k k e r v l s l t e d , - t h e S w l s s S n o w a n d A v a l a n c h e R e s e a r c h $ t a t l o n a t W e l s s f l u h j o c h a b o v e D a v o s . A p p a r e n t l y t h e y r e -c e i v e d t h e l m p r e s s i o n t h a t a s l m l l a r r e s e a r c h c e n t r e i n C a n a d a c o u l d b e u s e f u l t o p r o c e e d w i t h s n o w a n d i c e p r o b -l e m s , A f t e r t h e v l s i t , I { r " L e g g e t m a l n t a l n e d t h e c o n t a c t w l t h t h e S w l s s S t a t i o n a n d l n 1 9 4 7 , h o t n l t i a t e d , o n b e h a l f o f t h e N a t i o n a l R e s e a r c h C o u n c l l o f C a n a c l a , a f l r s t r e q u e s t t o g e t t h e c o - o p e r a t i o n o f a m e m b e r o f t h e S w i s s S t a t i - o n f o r - a l l m i t e d p e r i o d l n o r d e r t o h e l p a n d d e v e l o p
t h e Canadtan research program whlch had been started s e v e r a L y o a r s ago by G"J, Klein in the Dlvlslon of
M e c h a n l c a l E n g l n e e r l n g o f t h e N a t l o n a l R e s e a r c h C o u n c L l ' T h e w r l t e r , o c c u p L e d w l t h b a s l c r e s e a r c h o n c r y s t a l
-lognaphlcal, mechanlcal and hydrologlcal snoifrr problems,
h a d t h e g r e a t p r l v l l o g e t o b e a c c e p t e d 1 n t h l s m l - s s l o n " D e s p 5 - t e t h e f a c t t h a t s n o w l s , w h l t o a n d c o l d a l l
around the world', the sltuatlon ln Canada Ls dLfferent
f r o m t h a t l n Swltzorland ln many respects, R h e d l m e n -s l o n -s o f t h e t w o c o u n t r l e -s a r e d l f f e r e n t a n d so aro the e o n f l g u n a t l o n a n d t h e c l l n r a t e . T h u s , t h e p r a c t L e a l p r o * b l e m s a r e dlfferent l n t h e t w o c o u n t r L e s e v e n l f t h e
s n o w l s t h e s a m e . I n S w l t z e r l a n d , a v a l a n c h e s a r e p r o b l e m n o o L, whereas lce jams on rlvers are a qulte subordlnate p h e n o n e n o n . Agalnst that, the report of R.F" Legget
quotos rlver lce among tho f lrst problems and spend.s four f u l l p a g e s on thj-s toplc" A v a l a n c h e s a r e m e n t l o n e d o n l y
l - n o n e i e n t e n e e u n d e r t h e l a s t l t e m l r m l s e e l l a n e o u s t t o I t w a s very genorous and wlse as well not to ask
the wrlter for any recommondatlons when he Landed ln
C a n a d a l n O c t o b e r , 1 9 4 8 , b u t f l r s t t o s e n d h l m t o $ t s e h o o l i l for several months and acqualnt hlm wlth the sltuatLon
o n t h l s contlnent regardlng snow and lce. T h e s c h o o l h o u s e w a s t h e lmmense area betweon Ottawa, Washlngton" S a n F r a n c l s c o , V a n c o u v e r a n d C h u r c h l l l , t h e class rooms w e r e aII the places where snow and lce are studled at p r e s e n t , and where partlcular p r o b l e m s could be observsd a n d t h e teachers were nature herself and all those people w h o contrlbuted to reveal the true plcture of the wlnter
s l t u a t l o n b y v a L u a b l e l n f o r m a t l o n . ( I t l n e r a r y - see map, F l g u r e I ) .
I take thls opportunlty to thank all my named and
unnamed lnstructors for the unlque locture" My Canadlan
c o m r a d e a n d s e h o o l m a t e , D " C " P e a r c e , r e p o r t e d o n t h l s t r l p , c a r r l e d o u t i n t h e f l r s t t l : r e e m o n t h s o f 1 9 4 9 , t n A p p e n d l x C o f t h l s p a p e r "
The observatlons taken on the Journey have to be c h e c k e d v e r y c a r e f u l l y " S l n g l e o b s e n v a t l o n s r e v e a l j u s t the monentary state of a phenomonon but nelther average n o r e x t r e m e c o n d l t l o n s , T h o s e l a t t e r a r e p a r t l c u l a r l y
lmportant wlth regard to our problems" Wrong cqneLuslons
are worse than none, for exarple, ln the Selklrk moun-t a moun-t n s w e o b s e n v e d a v e r y l o o s e , n e a r l y u n s moun-t r a moun-t l f l e d s n o w c o v e r , v e r y d l f f e n e n t f r o m A l p l n o s n o w " O n l y b y a c c l d e n t
w e w e r e lnformed of the normal Alplne stretLflaatLon L n o t h e r w l n t e r s l n t h l s - r e g l o n . I n t h e s a m e r e g l o n w e c o u l d not notice one slngle avalanche ln sp5-te of eon-s l d e r a b l e eon-snow depth. T w o w e e k s l a t e r b a d s l i . d e s w e r e r e p o r t e d !
I n t h l s r e p o r t , e s p e c l a l l y l n t h e t h l r d S e c t l - o n ( C ) o n Partlcular F r o b l e m s , w e t r l e d t o f o l " l " o w a c e r t a l n p r o c e d u r e and to answer the follow1ng questl-ons;
L What dld we observo?
2 o lllhat dld we learn from other people or from t h e llterature?
5o TEtrat ls done Ln Canada or elsewhere to l n v e s t l g a t e and to master the problems? 4 . t V t r a t ls left to be done?
I n thLs way, wo hope to buLLd up a researeh program w h l c h d l s t l n g u l s h e s b e t w e e n t h e n e c e s s a r y a n d t h e p o s
-s l b l e o .
O f t e n p e o p l o hesltate to undortake an Lnvestlgatlon w h l e h has be.en done or ls ln progress el"sewhere" I am o f t h e oplnlon that dupltcatLon l-s a waste of tlme and.
effort only lf the fact of duptr lcatlon ls not known or
l f t h e l a t t e r l n v e s t L g a t l o n l s l e s s c o n s e L e n t l o u s a n d elaborate than the former orr€o A cortaJ"n duptrl-eatlon a s conpetltLon or control le of fundamental l"ntereet to t h e p r o g r e s s " A n o t h e r r e m a r k m a y b e a l l o w e d l n c l o s i n g
t h l s lntroductlon" I t ls the same expressed by Professor
P o Nlggll on the occaslon of the lnauguratlon of the new s n o w research laboratory ln 1943, I cannot do better
t h a n t o q u o t e h l s w o r d s :
r t N e c e s s a r y as lt ls for the responslble sclentlst t o l n s l s t t h a t a t f l r s t h e s h o u l d b e a l l o w e d t o d o h l s r e s e a r c h and that so called tpractlcaL workr should not b e d.emanded o f h l m o n t h e b a s l s o f u n c l a r l f l e d a n d faulty
l n f o r m a t l o n , h e w 1 1 1 nevertheless always be ready to m a k o h l m s e l f avallab1e for the requlrements of the hour.
O r r s t a t l o n l s t o b o a s c l e n t l f l c r e s e a r e h s t a t i o n l n w h l c h p r o b l e m s are to be examlned ab long range"H
EI rITE SNOVJ AND lCE $ITUATION IN CANADA
One lnportanb atm of the p3-anned snow and lce
r e s e a r c h p r o g r a m ls to obtal-n a coqplete surveJr on th.e s n o w and lce sltuatlon l n C a n a d a " T h L s l n v o L v e s d a t a o n t h e extenslon of the snow sover, of lts driratlon, a n d of lts quallty" D r l f t l n g a r e a s a n d a v a l a n c h e B o n e s should be mapped, rlver,s wlth lee jams or endangereei.
b y frazll l c e s h o u l d b e locatod and all these
observa-t l o n s and moasuremenis should be represenobserva-ted ln a eoR-d e n s e eoR-d m a n n e r o A gooci eoR-deal of the facts are weLl known a n o n g p e o p l e who are concerned wltir bhe specS.fle pro-b i e m s o pro-but of ten they are not avaLl"apro-ble to pro-bh,e pupro-blle.
$ f l t h thls pnesent attempt to ouillne the general s n o w a n d lce sltuetlone we do not wj.sh to antlslpate t h e e n o r m o u s task just mentloned" Its purpose ls only
to g5-ve a background to the fotrlowLng analysJ.s. Or
l n f o r m a t l o n on the snow cover l-s based on records of s n o w p r e c t p l t a t l o n t a k e n b y s t a t l o n s o f t h e M e t e o r o -J " o g t c a l Servlco, oh snow measurements earrled out by t h e NatLonal Research Counctl (ln co-operatlon wlth t h e Meteorologlcal $orvlce) durlng tho two wLnters
L946-4'7 and. malnl-y 194?-48 and flnaIIy on our pensonal
observatlons and measuremsrts taken ln t}le ranusual w L n t e r o f 1 9 4 8 - 4 9 "
L" the Snow Sltuatlon - Its Dl*Etrlbutlq4 aItd_,Qug}ltf,
A map showlng the average ennual itIrowfaLl ln Canada w a s p r e s e n t e d b y A . J . Connor to the Central Snow Confe-r e n c e , 1941. Fl-guConfe-re 2 ls a sfuipllfled c o p y o f t h l s m a p . W e notlce the maln f oature of the snow dlstrl-butlon:
o n a c r o s s s e c t l o n f r o m w e s t t o e a s t w e f L n d h e a v y s n o w -f a I I l n t h e w e s t e r n C o a s t R a n g e , a d r y b e l t b e t w e e n t h e C o a s t R a n g e a n d t h e m o s t w e s t e r n c h a l n o f , t h e R o c k y M o u n t a l n s ( M o n a s h o e a n d SeLklrk Range), hi-gh snow pre-c l p l t a t l o n l n t h e S e l k l r k s , a s m a l l b u t p r o n o u n c e d d r y zone between the Selklrks and the maln chaln of the R o c k l e s ( a l o n g t h e Cotumbla Val1ey head.lng north), and r a p l d l y d e c r e a s i n g s n o w f a l l e a s t o f t h e R o c k l - e s t o w a r d s
t h e p r a i r t e s , E a s t o f W l n n L p e g t h e A t l a n t l c l - n f l u e n c e i - s o b s e r v e d wlth steadlly lncreaslng snowfaLl the mone w e approach the Gulf of St. Lawrence" A separato
pro-flle from Vancouver through the mountalns to Calgany
shows some detalls of the snowfall ln the Mountaln Z o n e ( F l g u r e 6) " Apparently from west to east the h u m l d l t y of the alr ls stnalned out by the succeselon o f mountaln chalns, the western slopos gettlng the lLon I s share " Deep val.leys runnlng south-north
reeeLve very i.lttle snow, Nelther l-n the map nor 1n t h e p r o f 1 l e , t h e loeal varlatlons, p a r t l - c u l a r l y t h e v a r " l a t l o n s wlth tho altLtude, can be' reprosented,
I n comblnlng the precLpLtatlon map wlth a tem-perature chart and a wlnd map we could. flgure out
some -general data on the quallty of the snow. It w o u l d be betten, however,E6 io-bk aE some of the authentlc measurements on snow quallty taken durLng t h e w l n t e r 1947 and 1948 at several represontatlve p l a c o s a c r o s s C a n a d a .
Out of ten statlons where snow measurements have b e e n taken slnce 1946, the followlng s e v e n a r e s e l e c t e d :
S t a t l o n Provlnce R e p r e s e n t a t l v e f o r F$hltehorse 01d Glory Edmonton Churchlll tJlnnlpeg Malton G o o s e Bay
Unfortunately no measuremente have been taken ln the snow centre of the Provlnce of Quebec!
Flgures 4-|O are abstracts of dally and weokly observatlons. Tlrey show only the varlatlon of the snow depth and one typlcal snow proflle per uonth" (g futt r e p r e s e n t a t l o n o f a l l m e a s u r e m e n t s w l l l b e g l v e n l n a s e p a r a t e r e p o r t b y D . C . P e a r c e ) .
In addltS-on, we have some slmple snow proflles a v a l l a b 1 e taken on our trlp l n 1949. Tho places were!
R e v e l s t o k o , B , C . ( r S O O f t " ) M t . R e v e l s t o k e , B . C . ( 6 2 0 0 f t . ) G l a c l e r , B . C . ( 9 9 0 0 f t . ) s u n s h l n e L o d g e ( B a n f f ) A l t a . ( z z o o f t . ) G l a c l e r F a r k , M o n t a n a ( + g + O f t . ) ChurQhlll, Msn" T h e s e are lllustfated l n F l g u r e s 11-15. Y u k o n ( 2 4 0 0 f t . . ) N , W . C o a s t Zone M t . B . C. ( ZZSO f t. ) S "Ut, - Roeky Mt. Zone
A l t a " (22OO ft. ) ' l l f e s t e r n P r a l r l e
Manltoba l{udson Bay ( sub-polar Manltoba Ontarlo Labrador condi.tlone ) CentraL Canada ( E a s t e r n P r a l r t e ) Southern Ontarlo E a s t C o a s t Z o n e
A 1 1 m e a s u r e m e n t s a r e o r l g l n a l l y e x p r e s s e d b y f i g u r e s o r l e t t e r s ( s y n b o l s f o r c r y s t a l t y p e s ) , I n o r d e r t o p l o t them in a very condensed maru:er we made use of the s y m b o l s as shown on Chart 3u These slrarbols are lntro-d u c e lntro-d L r e r e o n l y t e m p o r a r i l y ; w e d o n o t w a n t t o a n t l c l -p a t e a n y d e c i s i o n o f t h e C o m m l t t e e o n S n o w C l a s s l f i e a t i o n . 0 n 1 y t h o s e s y m b o l s a r e g i v e n w h l c h are actually u s e d l n t h e p r o f l I e s " H e n c e t h e c h a r t d o e s n o t r e p r e s e n t a c o m p l e t e c L a s s i f l c a t i o n s y s t e , m " F o r t h e t w o s e t s o f p r o f l l e s , 1 9 4 7 - 4 8 a n d 1 9 4 9 n s o m e s y m b o l s a r e a p p l l e d i n a s l i g h t l y d i - f f e r e n t m a n n e r o O n l y t h e d l f f e r e n t h a r d n e s s s e a l e h a s t o b e e x p l a i n e d . I n t h e m e a s u r e m e n t s f a r 1 9 4 7 - 4 8 , t b e h s r d n e s s g a u g e w a s t h e p l a t e l n s t r u n e n t o f t h e C a n a d l a n s n o w k l t e t h e m e a s u r e m e n t s f o r L 9 4 9 w e r e t a k e n m a i n l y b y t h e S w l s s c o n e p e n e t r o m e t e r ( R a : n - m s o n d e ) . At present it ls not yet
s e t t l e d h o w t h e r e a d i n g s o f t h e t w o l n s t r u m e n t s f l t t o g e t h e r , s o y y e c h o s e l n d e p e n d e n t s c a l e s f o r t h e s u b -e l a s s l f l c a t i o n r l s o f t r l o t t m e d i u m l r and tlhardtl. D i s c u s s i o n o f t h e M e a s u n e m r e n t s P r o f i l e s o f 1 9 4 7 - 4 a T h e s e m e a s u r e m e n t s , t a k e n n o w f o r f o u r y e a r s b y t h e N a t i o n a l R e s e a r c h C o u n c i . l w l t h t h e g r a t e f u l l y a p p r e c l a t e d c o - o p e r a t l o n o f t h e M e t e o r o l o g l e a l S e r v i c e o f C a n a d a o a r e t h e b a s i s o f o u r k n o w l e d g e o n t h e s n o w q u a l l t y i n C a n a d a . T h e o b s e r v a t i o n s o f 1 9 4 6 - 4 7 w e r e r a t h e r s p o r a d . i c a n d l n e o n s l s t e n t l n m a n y r e s p e e t s l t h o s e o f L 9 4 7 - 4 8 a r e o f rnuch hlg[er quality" Unfortunately the new set for
1 9 4 8 - 4 9 h a v e n o t b e e n r e c e i v e d y e t .
lltle do not lntend to critieize here some i-ncomplete o r i n e o n s l s t e n t d a t a , b u t r a t h e r t o t r y t o m a k e f u l l u s e o f t h e v a l u a b l e l n f o r n a t i o n w e h a v e r e c e l v e d a n d h o p e t o r e c e i v e l n c o m l n g Jrears. Suggestions for simpllfying t h e p r o c e d u r e w 1 l l b e m a d e l n a l a t e r : S e c t i o n , I&rhltehorse A l t h o u g h t h e d a t a a r e n o t c o r n p l e t e , w € n o t l c e t h e c o n t l n u o u s l n c r e a s e o f s n o w d e p t h u n t l I t h e m i d d l e o f A p r i l a n d t h e n t h e v e r y s u d d e n a b I a t l o n . I n t h e p r e -v l o u s y e a r t h e s n o w h a d d l s a p p e a r e d a b o u t o n e a n d a half months earlier. ltre renember the dipastrous floods
ln sprlng, 1948, ln the Fraser Valley and we wonder Lf there ls a connectlon wlth thls phenomenon" The snow s t r u c t u r e w l t h the hardest and hoavlest layers 1n the
lower thlrd of the proflle ls sstandards" Only the
formatlon of a very hard baslc 1ayer ln Aprll at low
tenperature ls abnormal. As a whole, the snow ls ltght
and not more than nedlum hand. OId GLory Mountaln
T h e s e a r e p r o f l l e s o f t h e Alplne Sype. F"rom January to March there ls a conslderable progress Ln the metamorphosls wl.tb Lncrease of the speelfl-e gravJ"ty
a t t h e 3o-lnch level and decrease at the bottom. S o m e
o f the varlatLons ln the proflles h o w e v e r , l o o k a l i t b l e
strange. For exarple, the hlgh denslty of .51 ln Mareh
or the decroase ln hardness from Decenrber to January,
a n d . t h e decroase ln graln slze from March to Aprll, a r e
hard to comprehend, In L946 and 1947 Old Glory Mountaln reported only about half the depth of srrowo
Edronton
In January a warm spell consumed practlcalS.y all the snow and the same happened towards the end of Marsh"
Therefone the proflles show merely the loose snow of
t h e soparated perlods wlth prevalllng f l n e g r a n u l a r s a n d l l k e or feltllke c r y s t a l s , D e p t h h o a r w a s r e p o r t e d . ln the remalnd.er of ol-d. snow" The warm spe1I near the end of February w1ll be seen more pronouneed ln the
pro-flles of ]Slnnlpeg and Malton" The snow depth of 194?*48
ranged below that of L946-47 "
We wlsh to acknowledge the careful observatlons
taken sometlmes under unfavor:rable clrcumstances at the
alrport of Edmontono
Churchl11
Accordlng to the graph, we would thlnk Churehlll w a s a place wtth extremeLy deep snow" Thls ls actually
the sltuatlon ln the bush zone near the lludson Bay shore,
w h e r e a great deaL of snow, drlfted t n f r o m t h e n o r t h w e s t , ls caught (Flgure 24) " In 1946-4? onLy about one thlrd o f t h l s s n o w depth was measured at the same place" I n
o p e n unsheltored areas there 1s not a horlzontally s t r a
-t l f l e d s n o w c o v e r a t a l l . W e can flnd nearly bare ground a s w o l I as hard rlppled drlfts ( t r ' l g u r e 25) " Our proflles
s h o w snow deposlted ln layers of varlable denslty" D e n s l t y flgures of " 4 5 a n d h l g h e r a r e m e a s u r e d , b u t n o t b e f o r e the nlddle of Aprll, w h e n neltlng t a k e s p l a c e " T h e s n o w hardness ls sometfunes f a l r l y h l g h a t
I o w d e n s l t y . IIJlnnl-peg
F l r s t we congratulato thls statlon on lts very g o o d and accurete observatlonsl
Snow depth and structlre ln thls col,d snow are more or Less constant throughout the wlnter. It seems
a s lf the s1Lght varlatlons l n s p e c l f l c g r a v l t y a n d hardness w€re affected more by the manner the snow ls d e p o s l t e d ( w l n d lnfluence) than by secondary lnfluenees" The depth ln the second and thlrd week of January was d u e to settlement favoured by hlgh tenperatr.ue (-4o) a n d p a r t l y t o w l n d e n o s l o n ( u p t o 3 5 m . p . h , ) o A n o t k r e r warm spell ln February reduced the snow depth by 5
L n c h e s " In 1946-4? the snow depths were sllghtly a b o v e t h o s e of 1947-48"
MaLton
A l o w a n d s h o n t s n o w cover! - Stnlklng ls the dls-appearance of the snow 1n February and afterwards the f o r m a t l o n of a new blanket. A l t h o u g h t b , e s p e c l f l c g r a v l t y was Iow, a eonslderable hardness lras reported" T h e y e a r b e f o r e there was a llttte m o r e s n o w p a r t l c u -l a r -l y t o w a r d s spring" A s a whole, w€ recognlze that the snow cover ls of mlnor lryortanco ln southern O n t a r l o "
G o o s e Bpy
Due to the low terryeratr:res the snow dld not settle very rmrch before March" The maxlumm denslty l n t h e March pnoflle of ,28 ls very lowu The decrease of speclflc gravlty from January to Mareh, ln the
b o t t o m layen, comblned wlth a eonslderablo growth of t l r e erystals, ls lnterestlng. I n L 9 4 6 - 4 7 t h e s n o w d e p t h w a s nearly twlce as hlg!. as ln 194?-48" P r o f l l e s o f 1 9 4 9
R e v e l s t o k e a n d M t " R e v e l s t o k e
I n R e v e l s t o k e the lce layer at the bottom 1ndl-cates a ffi-ffi tn the early wlnter, aftep tbe
g r o u n d . was frozen the flrst t l m e . L a t e r t h e b e m p e r a -tures must have been low for a long tLme and wLthout g r e a t varlatlons" O n I y o n e o t h e r w a r m p o r l o d e a n b e r e c o g n l z g d ( l c e c r u s t s a t 4 Q c m J " ' l f f e were told that t h l s w a s u n u s u a l f o r t h l s p 1 a c e " I t l o o k s a s l f t h e t w o h l g h t e m p e n a t u r e p o r l o d s c a n b e r e c o g n l z e d - 1 ! t h e proflle taken at Mt. Rovelstoke at 80 Cltr' and 145 CItrs 1 r t h l s l s c o r r e e @ s n o w d e P t h o n M t "
R e v o l s t o k e w o u l d b e d u e t o a n e a r l l o r a c c u m u l a t l o n rather than to a heavler snowf,all ln tho hlgher lovel' T h e M t . R e v e l s t o k e p r o f 1 I e l s n e a r l y a r t b h e o r e t l c a l r r oneo Thls means a homogeneous snow cgver kept ln a laboratory ab a constant ground teryerature near the meltlnE piltnt and. at a constant surface temperature of about ltboC ror several weeks would flnally show a s l m l l - a r d L s t r l b u t l o n o f s p e c l f l c g r a v l t y a n d h a r d n € s s " I n f a c t , t h e a b s e n c e o f w l n d a n d t h e l a s t l n g c o l { c o u l d dlrectly be dedueed from the s,trange snow formatlons a r o u n d L h e t r e e s . ( g e e F l g u r e 2 0 )
G l a c l e r , ( 8 . C . )
A s L m l l a r p r o f l l e t o t h e o n o o f R e v e l s t o k e w a s found forty m!l"-es northeast of Revelsboko at Glacler ln the Ill6clllewaet Val1ey" In the uppor 8O orlo of s n o w w e w t l } f t n d p r a c t l e a l l y l d e n t l c a I c o n d l t l o n s l n t h e t w o p r o f l l e s a s f a r a s d e n s l t y a n d h a r d n e s s a r e concerne-d. fho samo spectacular fOruatlon as observed around Revelstoke and oven more spectacular ones were m e t w l t h l n t h e f o r e s t s n e a r G l a c i e r ( r l g u r e 2 L ) " I never have soen snow accumulatlons of thls klnd. HLgh
s n o w p l l e s o n s t u b s o f e u t t r e e s a n d t e l e p h o l e p o J ' e s may oicur ln the AJ.ps now and then and last for a few days, but usually they are blown off befone settlement anh 6rystal tranlfornitlon were able to tunn thesr lnto thoso flat elllpsoldal and corrpact mushroons"
Banff fsunshlne Lodgo)
The stratlflcatlon of a deep snow accum.rlatlon on the l-ee sldo of a wind-e:cposed rldgo ls opposed to the soft snow ln a sheltered, aroa. Because of the avalanche d,anger at the exposed slope we were not able to take a corrplete structure proflle by dlgglng a shaft" thls dangor was conflrmed by the hardness proflle, partlcu-lar[y by the soft layei at the bottom of the snow pack" Wlth6ut-any further com-ents the two proflLos show tho
G l a c l e n P a r k ( M o n t a n a , U " S , A . )
Thls proflle out of the mountalns near the lnten-n a t l o lnten-n a l bolnten-ndolnten-n telLs lts story velnten-ny clearly: l n t h e
early wlnter the flrst snow layors becamo wet and. wene
conpacted to an rfabnormallr hlgh hard.ness" The foll"ow-lng layers ltrere all deposlted under slmllar condltlons wlthout great wlnd lnf luence. Three penlod.s of sup€r-f l e L a l - meltlng (reln or sun) can be ded.uced sup€r-fnom the h a r d crusts. B e s l d e s thls the temFerature mrst have b o e n w e l l - b e l o w f r e e z i n g p o l n t . A c e r t a l n r o l a t l o n t o
t h e Revolstoke proflle 1 s o b v l o u s . ChurchllI
fhe dlfference ln the snow denslty, hand,ness and
structure betweon the sheLtered. wood.ed zone and. the exposed area ls strlklng and does not need any further comrent" Some very Lnterestlng varlatlons ln the
structure of tho drLfted snow shlelds cannot be shown
l n t h e p n o f l J , e s " T h e y can ln general be reeognlzed from the oolour of the surfaee" Jllle shaLl refer to thls p o l n t l a t e r ( s e c t l o n C , 5 ) .
Oenenal Conclusions
P n a c t l c a l l y a l l Canada ls covered for at least three months wlth a snow blanket nanglng from fLve Lnches to more than one hundred Lnchos ia depth" The snow quallty vanLes considerably from one cllmatlc nogl.on to another and. at the same place the duratJ.on and tho quallty of the snow vary fnom one year to another" Comparlng the snow ln Canada and ln Swltzer-land we flrst flnd that at one and the same plaee 1n
Canada the varlatlons ln tho snow featuros may be
s m a l l e r than at eertaln placos ln Switzerland because of n o r e unlform local cllmatlc eondltlons. B u t l n C a n a d a as a whole, the range of the snow quallty exeoeds that o f Swltzerland by far, partlcularly d u e t o t h e w l d e r t e t r y e r a t u r e range. T h u s , t h e s l n g l e p r o f l l e s a t " e unl-f o r m but there ls a great varloty ln tylpes ounl-f prounl-flles" Our moasurements are Just a first gllnpse of thls
v a r l e t y , A t p r e s e n t w e do not hlow what can be calLed average condltlons nor wh.at the extrem€s are, except f o r t L r e meteorologlcal eloments. T h e d a t a w h l e h w e r e e o r y l l e d ln the past three years are a very good gtart" They provld'e the valuable baslE of our knowledge on
t h e snow condltlons. (A eondensed lssue of tho records o f 1946 up to 1949 1s belng prepared), W e d o n o t t h l n k ,
h o w o v o r , t h a t f l n a l c o n c l u s l o n s c a n b e d r a w n y e t " O n the one hand, the methods of observatLon were not com-p l e t e and com-perfect ln every rescom-pect and, on the other hand, It ls obvlous that the range of the annual
varla-t L o n s can novarla-t be recognlsed. ln varla-threo wlnvarla-ters" A s e r l e s of years of further observatlon or even a permanent servi-ce wlth lurproved mothods 1s recommrended'
2 " The foe Sltuatlon
Thls paragraph ls only a suall note compared wLth t h e p r e c e d l n g o n o . T h e r e h r e v a r l o u s l c e p r o b l e m s l n C a n a d a , t o b e d i s c u s s e d l n t h e f o l l o w l n g s e c t l o n , b u t t h e r e l s n o t a g e n o r a l l e e s l t u a t l o n " T h e r e f o r e , I a m glvlng only a very brlef account on the well knorpn geo-graphlcal locatlon of the phenomena as sea 1ce, lake and r l v e r l c e , g l a c l e r l c e a n d p e r m a f r o s t '
S e a l c e l s d r l f t e d b y t h e c o l d L a b r a d o r c t r r r e n t
paralldf6the shore of Labrador as far south as about
4 2 o latltude a n d causes serlous navlgatlon problems" I c o b e r g s e n t e r t h e s t r a l t o f B e l l e I s l e a n d p a s s b y t h e west of Newfoundland," S€a 1ce ls found on lludson Bay too" The fact that the Bay ls frozen over almost eoln-p l e t e l y d r r r l n g t h e s e c o n d p a r t o f w l n t e r h a s b o e n e s t a b
-I l s h e d o n l y r e c e n t l y b y r e e o n n a l s s a n c e f l l g h t s a n d l n -d l r e c t l y b y a n a n a l y s l s o f t h e c l l m a t l c c o n d t t l o n s
around the Bay" I had the groat prlvllege to take part l-n one of the fllghts and to convlnce myself of Lhe lce c o v e r o n t h e B a y " fFtgure 27)
R l v e r L c e 1 s c h a r a o t e r l z o d b y t h e g e n e r a l s o u t h -northTi6iiii-E most of the Canadlan rlvers" Tho St"
L a w r e n c o Rlven wlth lts southern trlbutarles, m o s t r L v e r s of the Hudson Bay bastn and partlcularly the Mackenzle Rlver belong to thls predominant group" Only the
nor-thern tributarles of the St" Lawrence and several rlvers l n B r l t l s h C o l u m b l a f l o w t h e n r l g h t w a y t t l o o o f r o m
c o l d e r r e g l o n s t o w a r m e r o n e s ' P r e s e n e e o f l c e l n t h e l o w e r p a r t o f a r l v e r w b l 1 e t h e u p p e r p a r t L s u n f r o z e n c a u s e s - a l l s o r t s o f t r o u b l e s ( l c e j a m s , f l o o d s ) . S o m e -t l m e s a r l v e r r e m a l n s u n f r o z e n a -t n a r r o w s e c -t l o n s b e c a u g e of the ewlft flow, for example the St. Lawrenee Rlver
b e t w e e n P r e s c o t t a n d C o r n w a l l . F r a z l l l c e , a v e r y
troublesome phenomenon, 1s formea-Til-ffisectlons " There l s n o n e e d t o l o c a t e l a k e l c e a n d g l a c l e r l c e "
The extenslon of permafro-st ls not very wel-l known"
coherent permafrost lsffi?-ffighIy north of^the -5oc
l s o t h e r m , 1 " e " a b o u t 4 O O m l l e s n 6 r t h o f t h e O o C L s o t l i e r m . T h e s e l s o t h e r m s a r e h y p o t h e t l c a l l l n e s t I s o l a t e d . s p o t s t p r e s u m a b , l y oId remalnders not ln cLlnatlc equllLbrlo*,
o c c u r j u - s t north of the Oo lsotherm. T h e d e p t h o f p e r m a f r 6 s t has been measured at several pLaceso But
w l t h regard to lts varlatlon, w O cannot speak of e survey o f t h o p e r m a f r o s t d l s t r l b u t l o n n o l t h e r l n h o r l - z o n t a l n o r l n v e r t l c a l d l r e c t l o n "
PARTICI'I"AR SNOW AND ICE PROBI,EMS
V{e try to outlLne the problems Ln a certaLn natural order, beg5-nnlng wlth problems related to tho appearaJlge o f s n o w 1"e. to the preclpltatlon, t h e n d e a J - l n g w l t h
snow on the ground and approachlng lncreaslngly tecLrnLeal
p r o b l e m s . H o w e v e r , t h e s e p r o b l e m s c a n n o t b e s e p a r a t e d . p r o p e r l y r 4s, for exarryle, snow drlft l s r e l a t e d t o
h y d r o l o l i r " - w e l 1 a s t o s n o w c l e a r 1 n g , a n d g l a c l e r s h a v e t 6 range-under lce problems as well as under snow problems.
A c c o r d l n g t o o u r e d e r t h e f l r s t p r o b l e m w o u l d b o t h e forecast of snowfall, T h e M e t e o r o l o g l c a l S e r v l c e L r a s b e e n E @ w i t h t h l s t a s k f o r m a n y y e a x . s
and we w111 not l-nterfere" But we hope that a eontlnuous
and close relattonshlp between meteorology and snow
s c l e n e e m a y b e e s t a b l l s h e d a n d m a l n t a l - n e d o A n e w f l e l d of @onmon interest w111 be the modern Rexperlmental m e t e o r o l o g y t t l n l L i a t e d b y V " J " S c h a e f e r t s c l o u d s o € d l n g e x p e r J . m e n t s , w h t c h h a s a l s o b e e n l n v e s t l g a t e d b y t h e Dlvlslon of nfeehanleal Englnoerlng of the Nattonal R e s e a n c h C o u n c l l .
I . H y d r o l o g J . c a L A s p e c t s o f S n o w
The two fundamental questLons of intorest to
agrlcul-ture and hydroelectrlc power productlon regardlng snow
arg !
( a ) Wkrat quantlty o f w a t e r l s a v a l l a b l e a s a w h o l e at the outlel of a glven dralnage area durlng t h e a b l a t l o n p e r l o d o f t h e s n o w c o v e r ?
f b ) W b a t f l u c t u a t l o n s o f a r l v e r a r e t o b e e x p e c t e d w l t h a g l v e n ( o r e x p e c t e d ) p r o g r e s s o f t h e
weather ln the dralnage aroa and a glven snow c o v e r a g e ?
T h e a n s w e r t o t h e f t r s t q u e s t l o n ls glven by a long-t e r m f o r e c a s long-t o f r u n o f f b a s o d o n long-t h o s o - c a l l e d s n o w ggryg1. Thl s ls an emp tr ical, statlstlcal proe Effie .
Questlon two can only be answered after an ana-l y s ana-l s o f a s e r ana-l e s o f s ana-l n g ana-l e p r o p e r t ana-l e s a n d e v e n t s , a s fon exanrple the total heat economy of the snow covere t h e w a t e r s t o r a g e c a p a c l t y o f s n o w e t h e v e l o c l t y o f w a t e r p e r c o l a t l o n a n d o t h e r a s p e c t s "
( a ) S n o w s u r v e y
T h e p r l n c l p l e o f s t r e a m f L o w f o r e e a s t b a s e d o n snovr survey was adapted by Dr" JoE. Churohu ttre Pr9: moter of the Internatlonai Conmlsslon on Snow and lts P r e s l d o n t f o r m a n y y e a r s o A t p r e s o n t l t l s a p p l l e d - l n extond.ed snow survey systems, reachlng from Calfornla up to BrLtlsb Co1umbla and cover'lng parts of Eastern C a n a d a "
The general prooedrne of the snow survoy 1s thlsa-A t v a r l o u s c a r e f u l l - y s e l e c t o d p l a c e s o f t h e
d r a l n a g e a r e a l n q u e s t l o n , e o u r s o s s e v e r a l h u n d r e d f e e t long are staked out and marked permanently" At a-flxed, day-ln early sprlng befone the meltS'ng season beglns-,
thb water ehulvatent of snow cover !s measured by taklng s n o w s a m p l e s l n r e g u l a r s p a c e s a l o n g t h e s n o w e o u r s e s e A repres-ent attve water equlvalent for the area ls eom-puted and matehed wlth tho correspond'lng flgures of prevlous yeans for whlch the stream fl-ow ls known.
, The enrplrlcal functlon between water equlvalent and runoff ls lmproved year by year" But the runoff flguros always scatter conslderably around the hyp91 t h e t l c a l e a l l b r a t l o n c u r v o d u e t o f a c t o r s o n l y p a r t l y knovrn" It ls obvlous that ln chooslng the locatlon of
the snow courses an arbltrary element ls tntroduced lnto t h e s y s t e m .
A s a n f u p o r t a n t r e q u l r e m e n t , l t l s p r o p o s o d t o 9on* sld.er the degree of molsture saturatlon l.n the ground b e f o r e t h e neltlng perlod"
The so-called. ssoll prlmlng factorE ls d.etermj.ned from the amount of llquld preclpltatlon |n the prscedlng f a L L ( A u g u s t , S e p t e m b e r , O c t o b e r ) , f r o m ' s o 1 l m o l s t u r e measurenents or fron the flow of the rlvers ln the falI.
A seml-ery1rl-'ca1 correetlon ls added to the measured w a t e r equlvalent of a dralnage baslno
M o n e and more lt became deslrable to h,ave a f,lrst rough forecast ln sprlng or even Ln wl-nter" Tborefore t h e snow courses ln several baslns are sampled ln
December or January and then at monthly lntervaLso Ol r e p e a t e d l y vlsltod s n o w coursese care should be taken to get undlsturbed snow sampJ-es" Sometl-mes the snow surveyors do not worry about thls" They thlnk that a v o r t l c a l c o x r p a c t l o n b y s k l or snowshoos does not affoct the water equlval-ent of the underlylng snowe and they a r e certaLnl)' right. l l o w e v e r , thelr tracks w11l be levelled dunlng the next snowfall or drlftlng spell and thls moans that more snow wlll be deposLted thero than on the average, One sanrple casually taken Ln an old t r a c k does not lnflueneo the result a great deal of course o
S o n e t l m e s the questlon was d.lscussed whether evapof atlon should be consldered ln ord.en to lmprove
#
the forecast of runoff . f thlnk normal evaporatlon l-s i n v o l v o d ln the emplrlcal calLbratlon of the rethod." For perlods of abnormal evaporatlon aftor the sarpllng d a t e , supplementary posltlve or negatlvo correctlon may be glven to the runof f forocast. llttr€ wonder lf
evaporatlon pLaya an lmportant part at all ln the entlre b a l a n c o of ablatlon, A c c o r d l n g t o o u r o b s e r v a t l o n s
taken ln Swltzerlandr. the evaporatlon on a snow surface ls low Ln the cold wlnter months of January and February, tttowtt means below about Oo2 nn" water equtvalent per day on the averago, In tho nlghts and often durlng the days e o n d e n s a t l o n p r e v a l - I s " T o w a r d s e p r l n g t h e l o s s b y e v a -poratlon lncneases and reaches lts maxkmm when the snow
sunface ls wet and the absolute humldlty of the alr l-s s t l l I l o w . A s t t h l g h t t e v a p o r a t l o n w e conslder flgures above 5 xflsr. water equlvalent per day fmeasured for e x a n p l e In Aprl1 on Welssfluhjoch, 8700 feet) " Later on ln May and June, the closer the dew-polnt of the alr approaches the temFerature of the meltlng snow, the more e v a p o r a t l o n from the snow ls reduced and at a dew-polnt above the meltlng tenperature condensattron 1s measured. a g a l n , p r o v l d e d that there ls snow left on the ground" Tlme and angle of exposure are always lnportant factors. T h l s ls only a genoral plcture of a vertrr complex problem"
trVlrat tho sltuatlon ln Canada 1s we do not know. Tho on3-y lnforrnatlon we have ls an estlmate we were told that
ln Chlnook areas up to 25fi of tine snow evaporates, I f t h l s ls correct, lt wouLd be worth wtrlle to study m o t h o d s to reduce evaporatlon and proserve snow for agrleultureu At present we only can thlnk of accu: rnrlatlng snow by hedges or dltches placed
perpendleu-l a r 1 y t o t h e g e n o n a perpendleu-l d perpendleu-l r e c t perpendleu-l o n o f d r perpendleu-l f t , B u t f l r s t , e v a p o r a t l o n has to be noasured and studled 1n d.otalI" Thls ls beyond the scope of the standard. procedure
of snow surveylng"
Snow Sunvey Systems ln_qAA" and Oanad.a
c o - o p e r a t l v e s n o w survey s y s t e m o f w e s t e r n A m e r l c a J o l n e d t h e F e d o f a l S t a C o * o p e r a t l v e S n o w Survevs N e v a d a " C a l l f o r n
ontana e ol.umola iinow s o A l t o g e
-e r -e a r -e about s n o w c o u r s o s o groups lnterested and co-operating ln the snow survey vary somewhat from one State to another" The central autho-r l t y l n t h e l l n l t o d States Ls the U"S" Department of A g r l c u l t u r e f s o t t C o n s e r v a t l o n S e r v l c e , D l v l s l o n o f I r r l g a t l o n ) ; o t h e r c o o p e r a t S . n g fe d e r a l b o d l e s a r e s
-U , S o G e o l o g l c a l Survey (stream flow measurements) U . S " $ J e a t h e r Bureau
U . S " F o r e s t S e r v l e e N a t l o n a l P a r k S e r v l c e Bureau of ReclamatLon
The survey ln the si.ngle (partly overlappLng) zonos l s d l r e c t e d b y loca1 lngtllutlons a s for example the Nevada Agrtcultural ExperS.ment Statlon (Reno), and the
O r e g o n A g r l c u l t u r a l S t a t l o n ( M e d f o r d ) . T h e p e r s o n n o l f o r t a k l n g the measurements conslsts of:
S n o w surveyors (own personnel of the eo-operatlve snow survey)
F o r e s t rangers P r l v a t e p a r t J - e s
In generaL there ls lack of sultable porsonnel. Immense d l s t a n c o s have to bo travelled t o c o v e r t h e s u r v e y e d area. flho can afford to send out only well lnstructed a n d eonselentlous observors for days and weeks to take t h e o b s e r v a t t o n s at the most desolate and remote corners?
fhe Brltlsh Co1umbla snow sunveys and runoff fore-c a s t s forffisln, B o c o a n d , lower coastal a r e a s ls oper"ated by the Water Rlghts Branch of the D e p a n t m e n t o f L a n d s a n d Forests of Brltlsh C o l u m b l a ( V l c t o r i a ) " B e s l d e s t h e c o n n e c t l o n w l t h t h e U n l t e d . S t a t e s , t h e r e 1 s t h e c o - o p e r a t l o n o f l the a r e o f fn
Donlnl-on Departnent of Agrlcul.ture D o m l n l o n M e t e o r o l o g l e a l S e r v l e e Domlnlon Water and Power Bureau Natlonal Park Ser"vlce
P r o v l n c l a l a u t h o n l t l e s Prlvate corupanles
Flfty-three snow courses tn the Columbla basln are
v l s l t e d regularlyo I n t h l s a r e a t h e s n o w m e a s u r e m e n t s a r e corrected by a factor whlch ls deduced from the p r e c l p t t a t l o n l n t h e p r e c e d l n g f a l l "
Jolnt fnternatlonal Snow $urvey ln tho St. Mary and MlIk Rlver Dralnage Basln
$even snow courses and twenty-sevon stream gauge s t a t l o n s were set up ln 1922 ln order to Lnvestlgate the corryllcated water rlgLrt s sltuatlon along the
southern border of Alberta and Saskatch€w8rro The snow e o u r s e s are located ln tho Glacler Park aroa. O n the Canadlan sl-de, the Calgary Branch of the Domlnlon Water and Power Bureau ls concerned. wlth thls survey.
An lnterestlng statement was made ln thls survey a r e a , after a forest flne deprlved a large aroa of the f o r e s t cover. T h o r u n o f f c h a r a e t e r l s t l c s o u t o f t h l s erea were not changed at all after the ovent"
Snow Sunvey of the Bow Rlvor BasLn
Around Banff and Lake Loulso elght courses aro sampled by the Domlnlon Wator and Power Bureau (Calgary Branch) for the controL of the Bow Rlver. We have no
lnformatLon concernlng other snow eours€s ln the oastern f o o t h l l l s o f t h o Rocky Mountalns. A better control of the water of the eastern Rockles by extendlng the snow
survey to the baslns of the Athabaska River and North S a s k a t c h e w a n Rlven aeems to be advlsable wlth regard
t o t h e lncreaslng irportanee of lrrlgatlon l n t h e w e s t e r n p r a l r l e s "
Snow Survey System of the Ontarlo Ilydro E l e c t r i c P o w e r Conlnlsslon
In the baslns of the northwostern trlbutarles of the St. Lawrence Rlver numorous snow courses were
l n s t a l l e d s e v e r a l y e a r s ago. At present there are about slxty courses. Tho procedune of taklng eamples and com-p u t l n g the stream fLow ls the same as ln the west. For
v a r l o u s reasons the accuracy of forecast ls smaller, One reason may be that for want of referenee polnte ( a few years of observatlon) the calLbratLon curvss ane not yet coruect" As another roason we are sug-gestlng the d,lfferent character of the qblatlon Ln a nather flat and open reglon and in a mountalnous ter-r a l n " I n the f ornor, wo expoct a meltlng perlod of varlable duratLon from one year to another. Accordlng t o thls, t h o loss of wator by evaporatlon and soll prlmlng 1s not the same ln dlfferent years, whereas ln
the mountalns neltlng Lasts longer and ls less Lnflu-e n c Lnflu-e d by short pLnflu-erlodlc fluctuatlons o f the weather" In any case the problem should be choeked carefully,
Flgure 16 shows rouglrly the total are& under snow survey ln Canada.
We were surprlsed to learn that no atterryt has been made ln Canada to measure snowfaLl by prgclpLtatlon gauges (or are we mlslnformod?). fhe wlnter- preclpE-tatlon ls usuaLly determlned by measurlng the depth of fresh snow caugfrt on a boand and dlvldlng the f lgure by
ten ln order to compute the water equlvalent, New fallen snow ls supposed to have an average speclflc g r a v l t y o f O . 1 . I t l s e a s L e r t o c r l t L c L z e t h l s p r o c e -duro than to propose better methods" However, everyone who has to measure dally snowfall knows that thls be-comes gradually more and more guessnork the stronger t h e w l n d 1s blowlng. U n f o r t u n a t e l y , t h e p n e c l p i t a t l o n gauges suffer from the sq.yre dlsease. On the one hand, t h e n e s u L t s may be falslfied b y a t o o h l g b eatch of drlfttng snow and on tho otber hand, tho wlnd may pre-vont the fall-lng snow from enterlng the catchlng mouth. Everytb.lng depends on the aerodynamlc shape of the
gauge and the settlng up. Extended studles on thls
pnoblem have been made for a long tlme ln varlous cor.ln-trl-es and varlous tJrpes of shlelded and unshlelded
gauges have been developed, apparently wlthout deflnl-t l v e g u c c e s g .
F \ r r t h e r a s p e c t s of thls problem are dealt wlth ln S e c t l o n C 15, rr$nowdnlf trr.
