OCTOBER, 1980
Num-
ber of sample
1 2
8 4 5
6
7 8 8
10
12
13 14 15 16 17 18 19 a0 ai 22
n 34 25
28 27 28
29 80 a1 Sa 33 34 35 2~3 87 88
89 10
41
42 Is 44 45 46 47
43
11
1 Inches.
MONTHLY WEATHER REVIEW
Dataof precipita
tion
lQ29
June 11 June 12
June 13 June 30 July 19 sept. 16 Rapt. 18
sspt. a8 Oct. 10
oct. 12
oct. m Oct. 23 Oct. 29 Oct. 31 Nov. 10 Nov. 13 Nov. 18 Nov. 27
Dec. 1 Dec. 13
an. a Jnn. 7
an. 8
Jan. 13
Jan. 14
Jan. 17
Jan. 21 Feb. 16 Feb. 24 Feb. a5 ---do--- Feb. 28
Mar. 17 Mar. 18 Apr. 11 Apr. 13 Apr. 15
Am. 16
Apr. 20 Apr. 27
Apr. 28 May 1
May 2 May 4 May 7 May 11
May 16
May23
--
TABLE 1.-Rain and anow at Mount Vernon, Iowa
ao4 a 5
o.oa a8
0.6
a iz 0.16
a i 0.24
0.8 a i 6
a 0014
0.5
a m
0.12
0.4
0.26 a12
0.4
0.0025
a2 0.16 0.6
0.6 0.4
0.5 0.3 0.4
0.4
ala
0. cn 0.08
0.06
0. 16
0.8 0.5 a6
0. 16
a i 0. 6
0. ia
am a 0 7
a1 0. 8 0. 14
a m i 6
.-___--
a m i 4
0.08
am14 Traces. a m ________ am a0014
a m i 4
a m 0.005
________
ami
am
_-__--__ 0.003
________ a0829 0.0010
_-______
0.075
0.004
Traeas.
T r a m . Trncas.
Traces. T r m . Tram. 0. 0001
Traces. 0.0007 0.0025 0.0015
a m 0. ooo4
ami 0. ma ami 0.0001 0.m 0.0025 0.0025
a0014
a m 5
Tram. 0. cm5 0.02 0.0007
0.3 0.8
0. 6 a8
0.25
0.3
1.0
0.6
0. 75 a8 0.2
8
.a
13
4
6
3 6 2
2 2
0.6
0.18 0.3
0.3 0.4 0.25 1
1. 1 0.2 0.16
a 3
a 25
a3
a 4 a 4
0. ia
.75
a 5
a i
a 5
0.25 do..--
1.2 k d o ----
a4
r r w .
a 18
a%
a 4
a in a s aH aM
a07
ane
0.112
a 16
0.29
0.272 0.012
a 0 1
0.18 1.4
a3a 0.16
a29 0.16
a36
0.48 0.112
0.38
ale a 2 5
0.8
0.33
0.8
a 3 6 0.72
asn 0.38
a 4
0.16 0.38 0.32
0.m 0.001
0.01 _-______
________ --____-_ ________
________ 14.m
________ 17.75
________ 17.75
________ 17.7s
10.10R --____- ______._ l a 0 5
________ 24. a5 1.81 4615
________ 3.65 0 .7 8 ~ 11.65
________ 10.65
________ 7.81
_____-_- 17.75
________ 11.35
24.86
2 5 7 &45 1.04 31.05
_-____-- 6.1
________ 16.33
______._ 2 1 3 a493 --.____
0.837 24.8
________ 7.81
___ _.___ 21.3
_-_____- 4.97
0.013 24. fL5 0.123 4 2 6
0.219 2.6
a m 10.w R M ~ 17.4
a233 31.95
________ 3.55
a m 24.85
o .1 ~ 10.8 a247 17.45
________ 23.7
________ la65
________ 7.1
0.185 10.66
0.088 21.3 0.123 2 5 4
_-__-_-_ 2 7 5
______._ 31.95 0.0042 17.76
________ 3.55
________ 31.m
__-_---_-___---
________ iae
0. OM
a8 0.112
0.2
a OM a m
. - _- - -,
a 112
aa6 a m
a 78
am a m
0.136
0. 6
0.015 0.03 0.28 0. 2
0.72 0.78
0. 6
0 32
0. 08
0.45
0.30
0. 38 0.72
0. 16 0.36
0.32
0.112
0.32 0. 01
0.01
0.01
aae
a 36
a 36
a 16
a 112
a 16
a 138
.___--
.____- .___--
2.88
1.64
6.9 0.2
2.64 8.86
5.8 246 0.81 0.18
0.3 0.13
1.81 4.70 1.81
1.2
0.8
1.81
10.8
8.71
a. 2s
m g i d Albu-
I
Sul- I/llle Chlo- as
phated c b b monia rides
______ ____ 3 .0 m
__________ 1.4531
__________ 1.0087
_______-__ 1.4084 0.0721 _______.__
_______ __. 0.7248
__________ 5.63% 0.3079 7.8527
0.05.59 1.0672 0.4373 0 .6 W
0.2816 5.4364
_____.____ 1.1071
__________ a-2
__________ 0.213
_________. 1.8624
__________ 0.0852 0.0278 ____. ____.
0.0489 ________ __ __________ 1.2331 0 .m 1. 1752
_______ ___ 0.4832
__________ 0. aw
-1-1-
0.94 I 0.0018 1.34 ___._.____
3.40 1 0.0105
5.44 0.0014 7.52 0.0167 0.72 __________ 1.46 0.OW 0.94 0.05i9
5.44 0.0070
6. 53 0 .m
0.8 0.0110
8.16 0.0217
3.63 0.0139 15.94 __________ 1.83 ________-- 0.14 __________ 0.046 __________ 0.013 __________ ._------- -__-_-----
0.7731
1.8418
14.4812 3.1275 5.7W
0 .W 0.7637
1.5837
0.7214
0.5s32 0.WM 4.8324 3.2216 5.7574
4.8032 0.1006 0.2485 _________. 23363
419
..__._.-- 8.52
1.36 3.63 0.567
6.8 1.13 2.62 0.07 9.07
22.88
18.45
45.37
278.43 3.53
10.2 10.2
a m ._-_-__--
TABLE 2.-Dala from Table 1 converted to pound8 per acre
11 inch rain 0ve.r 1 aae-228,876.0 pounds. 12 inches snow-1 lnch rain]
40.83
3.m 49.0 15.01 49.0 10.81 32.67 8.36 95.Z 111.1: 21.82
6. l i
11.61
0.8
1.3:
0.2:
~
________
._______.
------__. ------__.
Nitrim
-
0.91
10.8
6.4 0.81
1. 13
2.0 3. 17
2.26
. - - - - - - .
. - - - - - - .
. - - - - - - .
0.02
_________
FIW ,mmonli
-
3.8 7.6 35.3 14. 5
7. 6
11.3 'I. 6
__---__-
am7 1 0.402;
__________ 1.0701
NOTES, ABSTRACTS, AND REVIEWS
Some Problems of Modern Meteorology' by D. Brunt- I. The present position of theories of the origin of cyclonic cdcprcssiOns.-The main features of the cyclonic depres- sion of middle latitudes are its center of low pressure and its associated system of winds which blow counterclockwise aaoupd this center. Now the pressure a t any level meas- urem to 8. high degree of a proximation the mass of air
the existence of a center of low pressure dyotes that air hes been removed from the region, and it is clear that the removal must finally be in a horizontal direction. Theories of the origin of depressions differ fundamentally only in the mechanism which they propose for this re-
m o d of air. I9 lpight be thought that a center of low pressure could be forbed by air diverging outward from a center, moving pveFywheI% in a horizontal direction. It is known, how-
the Northern Hemi-
sbove umt area of horizont ap surface at that level. Hence
The only alternative is convergence towards the central region, which by a similar line of argument is seen to pro- duce a counterclockmse system of winds. The excess of air which would otherwise accumulate in the central region must be removed by vertical motion initially. But since the removal of the superfluous air to a higher level does not in itself produce a decrease of surface pressure, we must further postulate some mechanism capable of removing the superfluous air horizontally. There appears to be only one possible mechanism, an upper current moving with a different velocity and possibly in a different direction, from the currents of lower levels. We are thus led from the general nature of cyclomc depression8 to postulate two conditions as necessary for their forma- tion-firstly, an ascending current of air in the lower troposphere, strictly limited in horizontal extent, and secondly, an upper current dif€ eiin in speed or direction
the upper current has the same direction as the currents of the lower troposphere, it will be constantly moving forward in advance of the depression, and an clouds
center in the line of advance. These clouds would herald the approach of the depression. If on the other hand the u per current is in a Merent direction from the currents
current will f a f t o indicate the line of advance o the
or both, from the currents in the B ower troposphere. If
formed withm it will appear to move outward 9 rom the
o P the lower tro osphere, any clouds formed in the u per
P
420 MONTHLY WEATHER REVIEW OCTOBER, 1930
depression. Much h&s been written of the use of cirrus clouds as prognostics of the Line of advance of a depression, but the net result appears to be that cirrus movement may be anywhere within the two front uadrants of the depression (see Pick and Bowering, Q. J.%. Meteor. Soc., January, 1929, p. 71). Thus the observed movements of cirrus indicate that the upper current is usually oriented a t any angle up to 90’ with the direction of the lower currents. The fact that the cirrus movement is seldom, if ever, opposite in direction to the motion of the lower levels agrees with the idea that the prevailing air move- ment in middle latitudes is in general from west to east.
We are, therefore, in a positiun to aasume the existence of a strong upper current a t the cirrus level as a feature of all depressions, and aa such a current is a necessary feature of the formation of depressions on any theory, the only difference that remains between Werent theories consists in the mechanism which they propose to account for the vcrtical removal of air in the lower layers of the troposphere.
The two main theories available to account for the vertical removal of air are the “local heating” theory and the “polar-front” theory. The f k t of these as-
sumes that the air over a restricted region is heated to a higher temperature than its surroundings, or is heated from below by contact with heated ground or warmer sea until it becomes unstable. The heated air may then be capable of rising to considerable heights. The effect of high temperature may be increased by high humidity, since damp air is lighter than warm air a t the same pres- sure and temperature. If the lapse rate is less than the dry adiabatic but greater than the saturated adiabatic, and any surface air which is saturated and at a higher temperature than its environment begins to ascend, it will become increasingly warmer than its environment with increasing height. The motive power is the lower- ing of density of a portion of the air below that of its environment, and it is probable that the effect of water vapor on the rate of decrease with height of the tem- perature of the ascending air is an important factor in the convection. The phenomenon of ascent is not as
simple as we have supposed above. The ascending air can not remain intact during its ascent. Turbulence will be set up at its boundary, causing some mixing with the environment, but the effect of mixing is to share the defect of density between the total mass which mixes, and the whole mixture will be lighter than its environ- ment, and therefore capable of ascent. The mixing here described is a necessary feature of the formation of a
cyclonic depression by convection. The system of winds is regarded as an effect of the horizontal conver- gence of air to take the place of air removed by convec- tion, and the extension of the system of winds to con- siderable heights demands the removal of air from all levels up to these heights, and except in the lowest layers the necessary removal is brought about by the effect of mixing of the ascending air with some of its immediate surroundinp a process to which Sir Napier Shsw gave the name o eviction. ’)
Water vapor is regarded aa an essential factor in the
theory as stated above to the extent that the aacending
air is assumed to be saturated either initially or a t an early stage in its ascent. In completely dry au the same phenomena would demand enormous local differences of temperature. The mean lapse rate in the tropos here is about 0.6’ C. per 100 meters, the dry adiabatic brig 1’ C. per 100 meters. Thus ascending dry air would npproach the temperature of its environment at the rate
of 0.4’ C. per 100 meters, or 4’ C. per kilometers and ascent up to 5 kilometers would only be possible for air which initially had a temperature 20” C. higher than the normal surface temperature of its environment. If, however, we may assume the initial lapse rate to lie between the dry and saturated adiabatics, then a
relative1 small increase of temperature in the lowest layer w16 enable damp surface air to rise to considerable heights; or instability in a relatively shallow layer near the surface will act as a trigger to set in motion convec- tion capable of extending to the top of the troposphere. And it must be noted that marked instability when ro- duced b surface heating is limited to a relatively sh a f low
on the function of water vapor in the process, and on the effects of mixing of the ascending air with its environ- ment during the ascent. The “local-heating” theory which we have just out- lined thus reduces itself to finding a physical cause capable of producing instability in the surface layer, over a sufficient area. The most obvious cause to con- sider is the direct effect of solar radiation in heating the surface of the earth. But the direct effect of solar radia- tion on the surface of the sea is very slight, and produces only a small diurnal variation of temperature, with a
total ran e of about 1’ I?. Moreover, most of the cyclonic fiepressions of middle latitudes originate over the ocean. We can not, therefore, assume that direct solar radiation is capable of producing over the ocean the intense local heating of the air sufficient to give rise to depressions. There is, however, a plausible alteruative to this. Air originating in high latitudes, and moving to low latitudes, will be heated from below ns it passes over progressively warmer land or ocean, until a stage is reached at which marked instability occurs in the lowest
layers. The surface air will be at or near saturation, and when convection starts it can proceed to very great heights. We mi ht therefore expect that depreesiona should form in co k d polar currents. This is borne out by observation, since it is not infrequently noted that de pressions axe formed in cold polar currents. These are the only depressions formed over the ocean whose origin can be definitely ascribed to instability. The first clear discussions of the convection or locd- heating theory outlined above will be found in Espy’d Philosophy of Storms. Espy was also the first to em- phasize the importance of water vapor in the atmos h.
fluid” theories, as discussed recently by Shaw,* Brunt: and others. The main alternative to the local-heating theory ie~ the polar-front theory, developed during the lest 16
years or so by the Norwegians. This theory in a wre or less definite form can be traced in earlier writere, but it was left to V. and J. Bjerknes and their colleaguea to give it a definite form. Dove’ developed in some detail the idea that a cyclone could be re arded as a r q p af
wntem supported this view. Bigelow’ pointed ,out
that on the whole cyclones could not be regetdsd b having warm centers or cold centers, but that tha pbs
that the centers of cyclones usually occurred along 3 t
nomena could be more accurately described by sa
surface 9 ayer. It i s for this reason that emphasis is laid
The same ideas underlie what are known aa “ rev0 P Ving-
opposition between warm and col % currenta, an Is*
I Washin#on,~Mvnthlu Wmthcr Rcoicw, lW2, p. 251.
OCTOBER, 1930 MONTHLY WEATHER REVIEW 421
lines separating warm and cold currents. Again Shaw and LempfertO showed that the rain which fell in a cyclone could be explained by the forced convection due to the convergence of air, or by the ascent of warm air over cold air. V. Bjerknes’ combined Shaw and Lemp- fert’s picture of the cyclone with the ideas of Helmholtz.s The latter had shown that two currents of air of different temperatures and different velocities could flow side by side separated by a surface of discontinuity, the ar- rangement being stable. Bjerknes suggested that the cyclone should be visualized as a wave in the surface of separation, between a cold easterly or ‘‘ polar” current, and a warm westerly or “equatorial” current. The surface of separation, or more frequently its intersection with sea level, is known aa the “polar front.’’ The wave increases in amplitude, and a cyclone sometimes forms at the northern crest of the wave The theory is very strongly reminiscent of Emden’sg theory of the
origin of sunspots. In discussing this theory it is necessary to draw a clear distinction between the theoretical discussions of V. Bjerknes and the methods of analysis of synoptic charts developed .by his son, J. Bjerknes.’O The latter pictures the development, of a depression as starting with a straight line separating t,he cold easterly current from the warm westerly current. The first step is a bulge of the warm air into the cold air, and as the bulge increases, a well- marked center of low pressure develops at the tip of the bul e. The warm tongue is compressed by the cold air an d eventually all the warm air is pushed up from the pound. From this stage onward the depression decreases
in intensity, and its motion of translation dies away. We are not here concerned to describe the association of weather with the different parts of the system de- scribed by J. Bjerknes. The reader will find full descrip- tions of these in the original papers. The practical use
of these ideas has been elaborated by the author in a masterly way. Moreover, there is no question that in a large number of cyclones of middle latitudes the develop- ment of the cyclone is associated with developments of the polar front in the precise manner described by J. Bjerknes. The difficulty lies not so much in confhning the assoc- iation of cold fronts with cyclones as in obtaking a clear idea of the physical principles underlying the association. In the first place the polar-front surface is only inclined at a small angle of lo or less to the horizontal, and in any
gravitational wave formed in this surface the motions should be predominantly vertical. V. Bjerknes sug- gests that the effect of the earth’s rotation will be to in- crease the extent of the horizontal components of motion, so that they become enormously greater instead of much less than the vertical motions, but this process is not obvious. There is the further difficulty that the manner in which the warm air is caused to ascend over the cold air is by no means clear. Helmholtz suggested in one
6 The LUe History of Burlace Alr Currents, London, 19Cu3.
7 V. B knea The dynamics of the oircular vortex, etc. Qtofvbke Publikafioner, 2,
No. 4. ’& atr&ure of the atmosphere when rain Is falling. 4. J. R. Me4eor. Soc.. 4G,
le%Ekwitr&t. A m . W& m p. 647‘ 1889 p. 761 These papers we re r o d 4
in Wiase’aschaitliche Abhandihged of Heimhoitr and are glven In Abbe’s collected Trans)ationa Sedea Il.
0 Emden: Qaekugeln Ut edition Berlin 1807 Chapter XVIII. u J Bjerknes. On th;,structureof m v d g &na. Gcolynske Publikafioner 1 No. 2.
J. Blergnm Ad H. 6dbe.w Meteorologi~condltbm for the formtlon of ;ai;; ibid..
2, No. 3. J. Bjerknea and E. Solberg: LUe cycle of cyelonsr, and the polar-front theory of atmos- pherio drculatlons, ibid., 5, No. 1.
J. Bjalnes: Dlagwetic and ptqnoatlo applleations of mountaln obrvations, ibid., S, No. 6. eron and Swoboda: Wellen nnd Wirbel an elner guaaiatatlonUren OrenzlXche O ~u m ~ VmdflG#whm rnrt. LFnls U p t i p 3 No. 2. Thls pewr g l v e s a w oomplete 8- of the vlews of the dorwegtd s)&ool. A. Refsdal: Der feuchtlabile Nledemchlap, Qe4fyrlske PuUiCdNonrr, 0. No.12.
of his early papers that the warm and cold air would not in practice be separated by a sharp surface of dis-
continuity, but by a layer formed by the mixing of cold and warm air, and he further suggested that the initial ascent - takes place in the layer of mixing.
The outstanding physical difference between the polar- front theory and the local-heating theory is to be found in the cause of the ascent of air. In the one case the ascent is apparently largely due to dynamical causes, while in the other it is due to thermal causes. But this distinction must not be taken too literally, since atmospheric phe- nomena are seldom to be interpreted as purely dynamical
or purely thermal. Again Helniholtz showed that the cold and warm currents are in equilibrium when separated by a sharp surface of discontinuity, and it is not clear why the warm air begins to ascend up the slope of the wedge of cold air. Oscillations in the surface of separation should rapidly die out. It is, of course, possible that even in depressions formed at a polar front the initial stages are produced by thermal causes. But when the niotion of cold and warm currents is geostrophic, there-is no tendency for the warm air to climb over the cold air, as has been emphasized by Brunt and Douglas.” Helm- holtz also showed that the waves formed in the surface
of discontinuity should have wave lengths of the order of
1 kilometer rather than of the 1,000 kilometers which would be more appropriate in the case of cyclones.
To summarize our present view, we may say briefly that while it is undeniable that depressions frequently form at surfaces of discontinuity, and that the weather within them can be explained by the interaction of warm and cold currents at the polar front, yet it is not clear what causes Nor must it be
depression subsequently forms. I t is not even clear that the condition laid down earlier in the present article, that there must be an upper current differing from the current in the lower troposphere, is itself sufficient to determine whether a depression shall form or not. Rut this partic- ular question has never been investigated in full detail.
Exner la and others of the Austrian school of meteorolo- gists have regarded cyclones as formed, not a t a continu- ous polar front, but a t the edge of a discontinuous out- burst of cold air. The cold air bursting southward as a tongue projected into the warm current cuts off the supply
of air from the region to its left, causing a diminution of pressure at that point. At the same time the warm air
is dammed up behind the cold tongue (i. e., to its right), causing an anticyclone there. The theoretical discussion of these subjects leaves it uncertain whether the processes suggested would produce the changes of pressure which are actually observed in the atmosphere. Exner’s views on this subject are to be found mainly in his textbook, Dynamische Meteordogie, but a very complete bibliog- raphy of Austrian papers on this and allied subjects up to the end of 1922 has been given by Ficker.Is
Whatever view we may adopt concerning the genesis of cyclones, we find that the fundamental cause is always to be ascribed to the direct or indirect effect of horizontal differences of temperature over the earth’s surface. Since the horizontal differences of temperature are grefttest in winter, cyclones should be more frequent and more intense in winter than in summer. The strength of the currents in the atmosphere are proportional to the horizontal temperature gradients.
owth of the depression initially. overooked the r that frequently fronts occur at which no
~~
11 Brunt and Dougla~: Mem. R. Mctcor. Soe 3 No. 22.
1’ Emer: Dynamtsche Meteorologle. Id edition: Ohapter XII.
1’ Flcter. Md. 28.. March, 19%
422 MONTHLY WEATHER REVIEW OCTOBER, 1930
The ideas described above all ascribe to conditions in the lower atmos here the predominating r81e. Exner l4
pressure are brought about by advection, or horizontal movement of air masses of different temperatures.
C. I(. M. Douglas Is has also suggested in recent papers that the advecbon of low pressure at high levels may play an important r81e in the formation of cyclones, but the physical processes involved in this have not yet been thoroughly discussed. Kobayasi le has shown that if a column of revolving fluid draws in air of difTerent temperatures from different sides it may produce lines of discontinuity of temperature a t the surface. Any theory which shall provide a full explanation of the processes in a cyclone must explain the lowering of the stratosphere above it, and the relative cold in the tropo- sphere, and relative warmth in the stratosphere in a
cyclonic region. The statistical data bearing on this aspect of the subject have been given by the late Mr. W. H. Dines.'? Exceptionally severe snowstorm of October 18-19, 1830, near Bu$alo, N. Y. By J. H. Spencer, Weather Bureau, Bufah, N. Y.-The very heavy and wet snowfall of Saturday and Sunday, October 18 and 19, was south from Buffalo to Erie and beyond, where one of the worst storms of record occurred, amounts ranging from 6 inches to
3 or 4 feet falling over a great area, but worse perhaps in the Hamburg-Angola section. The temperature was near the freezing point. The Lake Shore and other highways of that section became impassible, and hun- dreds of motorists were stranded in their cars or near-by farmhouses and taverns some for 24 hours or more. Apple orchards were heavy with fruit, and the added wei ht of the snow broke down many trees. Many sha s e trees were also ruined. Telephone and power lines were down in many sections, and rail, bus, and steamship lines were hampered or interrupted. The roofs of some buildings collapsed because of the weight of the snow. A day or two before the storm summerlike conditions prevailed and late fall flowers were in bloom, even roses. The great fall of snow near the south shore of Lake Erie was caused by abnormally cold weather and moisture- laden west winds off the lake, occurring at a time when a
ronounced southwest storm area covered the entire rake region and districts to the northward. This dis- turbance remained nearly stationary over the Great Lakes for more than three days, causmg one snow period after an0 ther.
Buffalo, except the south portion, escaped the storm because west winds that blow over central and northern sections of the city do not come off the lake. Snowfall on Sunday, October 19, in the vicinity of Church and Franklin Streets, was nearly 2 inches; in the Delaware Park section it was less than one-half inch; and in South Buffalo 6 inches or more. Little snow fell a t the Buffalo From Buffalo north to Niagara Falls, northeast to &!rt- ockport, and east to Williamsde and beyond there was also little or no snow. At the time the snowfall a t
Angola was deepest, and highways impassible, there was no snow whatever 3 miles away on the shore of the lake, where the grass was green and flowers blooming, but with a misty rain. Dunkirk and Hamburg were among the cities without electric lights and power until the lines were restored after the storm.
on the other han B hassuggested that the major changes of
-
14 Exner Dynamiache Meteorologic Chapters XI and XII. 16 C. K. M. Doughs: Q. J. R. Melc&'. Soc., 64,1928, pp. 1Q-25; 55,1029, pp. 128-161.
16 Koba i: Q. J. R. Meteor. Soe. 4% 1923, p. 177.
17 W. $%ines: The c h a n r ~d c a of the free atmosphere; London, Mctcmologicat Ofice, QcOpnyrtaJ Memoirs, No. 13.
Among the losses reported by the press in western New York were the following: A building at the Angola airport caved in; also the roof of the Angola Hotel, resultin in damage of about $3,000. At Orchard Park
damage around $5,000. Thousands of dollars in damage to fruit trees resulted in the vicinity of Orchard Park and other sections. Several roofs caved in at Dunkirk, among them the Famous Store, which reported a loss of
$15,000. The roof of Floral Hall at the county fair grounds, Dunkirk, also caved in. Damage to shade trees and shrubbery, South Park, Buffalo, was estimated at $50,000.
The following are the amounts of snowfall reported to this office: Angola, 42 inches; Arcade, 7; Belfast, 2; Belmont, none; Bliss, 8; Boston, 30; Cherry Creek, 1;
Dansville, 2; Dayton, 15; Dunkirk, 36; East Aurora, 37;
Eden, 48; Ellicottville, 3; Franklinville, 3; Geneseo, 1;
Gowanda, 5; Hamburg, 33; Hamlet, 5; Holland, 24; Lancaster, 15; Mount Morris, 3; New Albion, 6; Orchard Park, 42; Randolph, 4; Sinclairville, 5; Silver Creek, 36;
Springville, 6; Strykerville, 36; Warsaw, 10; and West Valley, 4. by Dr. 0. W . Freeman, State Normal, Cheney, Wash. [author's abstract] .-Previous rainfall maps of Washington have been so generalized, especially in eastern Washington, that they failed to show as close a relationshi to the relief and to the vegetation of the region as was B esirable. Isohyets drawn on the present map used all the records available in the State for mean annual rainfall. Stations having records for only a few years were compared with Spokane and Walla Walla in eastern Washingtonand Seattle in western Washington as standards since these places have long continuous records, and such corrections as were needed were made and the adjusted results used in drawing the isohyets. In places where no records were available personal observations by the author of the ve etation and relief were used in the location of critical
In western Washington 20, 30,40, 60, 80, 100, and 120 inch isohyets were drawn. In eastern Washington 8, 10, 12,15, and 25 inch isohyets were added. This was found necessary because the usual jump from 10 to 20 inch annual rainfall, which is an increase of 100 per cent is too much to show the proper relationshi between farm crops
The rainfall of Washington is principally affected by the Pacific Ocean, the direction of the prevailing winds, the relief of the land, and the course of the cyclones. There are three zones of heavy rainfall crossing the State north and south. These correspond to the Coast Range, Cascades, and Highlands of eastern Washington. To leeward of the Coast Range the rainfall declines in the Puget Sound lowland, especially in the rain shadow of the Olympics where it is under 20 inches.
In eastern Washington the 15-inch isoh et corresponds
The 12-inch isohyet marks the fkut of the bunch grass and the preponderance of the sagebrush begins. Above the 12-inch isohyet wheat raising is generally successful. Between 10 and 12 inches the best farmers can still succeed in most years, although crop damage from drought is common. From 8 to 10 inches is quite definitely border-line farming and failures probably outnumber successes. Below 8 inches annually wheat raising is rarely tried any more and never
the roo !? of the Acme Veneering Co. collapsed, causing
A new rainjall map of the State of Washington
is0 1 yets.
or natural vegetation and the rainfa B .
to the limit of growth toward the dry lan c9 s of the yellow ine (pinus ponderosa).
M. W. R.. October, 1930 (To Face p. 422)
IIeavy snowfall (aZ inches) at Angola, N. P., on October 17-18, 1930
OCTOBER, 1930 MONTHLY WEATHER REVIEW 423
was permanently successful. Under these conditions irrigation must be used if crops are raised. Fortunately the heavy snows of winter the mountains in most years supply an abundance of irrigation water to fruitful valleys that lie in the rain shadow of the highlands. M. A. Giblett, 1894-193O.-The untimely death of M. A. Giblett in the crash of the R-101 on October 5
brought to aclose a life that was not only fullof accomplish- ment but also one that ave promise of a much enlarged
Giblett, in company of J. Bjerknes, paid a short visit to the central office of the Weather Bureau in the late summer of 1924. Together they made an analysis of tmhe working charts of the forecast division of the bureau and contributed a paper bearing the title An Analysis of a Retrograde Depression in the Eastern United States, published in this REVIEW 52:521-27. While at the Weather Bureau he endeared himself to the members of
the staff by his intense enthusiasm in his chosen work and his charming personality. The sympathy of his
friends on this side of the Atlantic goes out to the fam- ily and associates of the deceased.-A. J. H. Sunspots and presmre distribution.ig-The issue by the meteorological office of the daily charts of the weather in the Northern Hemisphere has enabled me to ascertain the barometric changes which take place from day to day in high latitudes. As a rule, the cyclones and anti- cyclones are large as compared with the po!ar uncharted area, and it proved possible to extend the isobars of the surrounding areas over the Arctic Sea. However, east Siberia could not, in the absence of the Japanese daily charts, which reach England about six months late, be dealt with.
From the partially completed charts the mean pres- sures were calculated for each day along latitudes 30°,
40°, 50°, 60°, 70°, and 80" north. When plotted they showed irregular periodic variations, some of which had a swing of something more than 25 days. As this is
about the apparent period of rotation of the sun and pointed to our chief luminary as the cause of the vari- ability of pressure from day to day, I decided to consider the sunspot question carefully. By the courtesy of the Astronomer Royal, I have been supplied with bromide prints for each day for January, February, March, and April, and been allowed to see some of the later negatives of the solar disk. Also, by the courtesy of the director of the meteorological office, I have obtained the pressure charts-issued to the public since March-for January and February. The sunspots have been plotted upon a diagram, the abscissae of which are days and the ordinates degrees on the sun's surface measured from the apparent center of the disk. They clearly show the movements of each spot or group of spots, as they approach or recede from the center of the disk, owing to the sun's rotation. An examination of this diagram demonstrates the fact that the pressure is low over the Arctic regions when there are sunspots near the sun's center, and that there are high pressures over the Arctic regions when there are no spots near the centre of the disk. Such low pressures due to sunspots occur in the long Arctic winter quite as markedly as they do during the summer. When the sun's disk was clear in the center on April 24, the mean pressure north of 60" was 1,025 millibars. On March 8
the mean pressure was 1,001 millibars and there were spots near the sun's center.
sphere of usefulness in t f l e years that are to come.
~
1) Reprinted from Natwr, London, Sept. 19,1830.
I hope to be in a position to publish full details con- cerning the matter soon after the receipt of the Japanese weather charts of the North Pacific area for June.- R. M. Deeley. The bora.-In a note on a recent geographical s+dy of the vicinity of Fiume, at the north end of the Adnatic Sea (Geogr. Rev., April, 1930, pp. 331-332), the following note on the bora appears:
The bora blows when a "low" over t?y Adriatic or Mediterranean causes a draft of cold air to sweep like a cascade" down the Dinsric inountzin sides. Its vehemence is at a maximum in the gaps, where the air is coinpressed and condensed. The unexpected and capricious gusts (refolr) are particularly dangerous to naviga- tion] but even on land they can easily upset a loaded railway car. Coiisequently the railways leaving Fiuine are protected at the most exposed points by palisades and thick high walls.-C. F. B .
City temperatures.-The yearbook of the Baden weather service for 1929 has just been published.*O This annual con tains the usual summary of observations in Baden, both surface and aerological. Two scientific papers are also presented, one of them being on the temperature distribution in Karlsruhe on hot summer days.21 In this paper Dr. Albert Peppler describes, in the form of tem- perature profiles and a detailed map, the local distribu- tion of temperature in and about Karlsruhe. The observations are obtained by the temperature survey method by automobile. The instrument used was an Assniann aspiration thermometer. Most striking is the exceptional contrast in evening temperatures between the interior of Karlsruhe and the wooded surroundings. The hottest parts of Karlsruhe had temperatures exceeding 30" C., while the woods nearby had temperatures from 25" down to below 23".
Owing to the marked contrast there was a slow flow of cool air from the country towards the city, ths flow being marked on the streets entering the city. The heated air of the city flowing out over the surrounding countryside produced such a sharp inversion of temper- ature that the locomotive and other smoke was closely held to a low ceiling.-C. F. B. Rain map of Australia for 1929.-Every year the Commonwealth meteorologst publishes a rain map of Australia on a scale of 130 miles to the inch. This map for 1929 shows many interesting contrasts. The least rainfall was 0.65 inch in the northeastern corner of south Australia. This was lowest on record for the station. The greatest rainfall was 120 inches at Innisfail, at latitude 17% on the coast of Queensland. There was a rainfall of 110 inches near Port Macquarie about latitude
32 on the coast of South Wales. This was the greatest on record at that place. Tasmania had even more, the maximum exceeding 150 inches on the western mountains. Spots in the southeastern lowland, however, had less than
20 inches. Printed iu the space around the map is a table and discussion of the rainfall of the year by districts, also small-scale maps of Australia showing the distribution of areas having more or less than average rainfall. On the back of the map are 12 smaller scaled maps showin the rainfall by months. In January, February, and darch monthly rainfalls of 30 to over 40 inches occurred on parts of the coast of Queens1and.-C. F. B. Climatological summary for Chile, August, 1930, by
J. Bustos Navarrete, Observatorio del Salto, Santiago, Chile.-During the first half of the month atmospheric
424 MONTHLY WEATHER REVIBW o m l q lrn
Sun’s zenith distance
8a.m. 7%.7°~7b.7b~~.70~B0.00~ 0.0’ ~60.0°~70.70]7b.70~7E.70 Noon
nmea 75th mr.
- Air mass Iaosl
mJk
time time A. Y. P. m.
e. b.0 I 4.0 I 3.0 I 2.0
I.I-1
2.0 I 3.0 I 4.0 1 5.0 e. ~----------
conditions were relatively stable with moderate inorease in temperature, but durin the last decade there was a
The most important depressions, all crossing the extreme southern region, were mapped on the 21st to 23d, 25th to 26th) and 28th to 30th. Anticyclones, advancing from southern Chile toward Argentina, were mapped in the following periods: 1st to 5th, 11th to 13th) and 14th to 21st. In the period 6th to 9th an antarctic HIGH crossed the continent in a
northerly direction.-Translated by W. W. R.
change to decidedly unsett 7 ed weather and general rains.
Clinzatologkl summary for Chh, September, 1830; by J. Bwrtos Navawde, Obseroatorio dcl Salbo, Sanidiago,
Cibile.--Like September this month was characterized by settled atmospheric conditions. Cyclonic storms of im- portance appeared in the extreme south during the periods 21st to 22d and 29th to 30th. During the remainder of the month anticyclonic areas dominated conditions and the weather was fine. The important H I m s , all of which moved from southern Chile toward Argentina, were charted in the periods 2d to 12th) 13th to 17th, and 22d to 26th.-Translated by W. W. R.
BIBLIOGRAPHY
C FITZHUQH TALYAN, in charge of Library
RECENT ADDITIONS
The following have been selected from among the titles of books recently received as representing those most lilrely to be useful to Weather Bureau officials in their meteorological work and studies :
Dclcambre.
La part de la m6t6orologie daw le succ6s du Paris-New York at5rien. p. 89-92. illus. plate. 39% cm. (L’Illustration. 27 Sept. 1930.)
Graphical means of identifying air masses. Cambridge. 1930. 27 p. plates. 28 cm. (Mass. inst. tech. Met’l course. Prof. notes. no. 4.)
On tides of the upper atmosphere. Kobenhavn. 1930. 15 p. figs. 25 cm. (Pub .Danske met. inst. Comm. mag., etc. no. 10.)
Ciclonea electromagn6ticos? n. p. 1930. 10 p. 26% cm. (Bol. del Centro naval. no. 483.)
Actinometros empleados en el observatorio meteorologico central de Tacubaya y su calibracion. Tacubaya. 1929. 46 p. 23 cm. (Serv. met. Mexicano. Obs. cent. Foll. num.
2. Rad. sol.)
Preliminary study of crop yields and rainfall in the Transvaal. Pretoria. 1930. vi, 61 p. figs. plate. 25 cm. (Trans- vas1 univ. coll. Bull. no. 19.)
1. Die scheinbare Flachenhellig- keit einer schwarzen Fliiche in Abhingigkeit vom Sonnena- zimut bei kleinen Sichtweiten. Danzig. 1930. 38 . figs. 27% cm. (Forschungsa des Starb.at1. Observ. Dnnzig.IPeft 2.)
Earl, Kenneth, 0 Turnu, Thomas A., if.;.
Egedal. J.
Escola, Melchor 2.
GorczyxhE, L p d i .
Haylett, D. G.
Kosfhmieda, Harald. Danziger Sichtmessungen.
Letsmann, Johannes.
Experimentelle Untersuchungen an Wasserwirbeln. Leipeig. 1927. p. 40-85. illus. 22 cm. (Sonderab: Gerlands h i - tragen zur Geophys. Bd. 17, H. 1, 1927.) McAdie, Alexander.
Poisson, Charles.
Ring, Laurence E.
Clouds. [Cambridge.] n. d. 22 p. plates. 30% cm. i
MBtt5orologie de Madagascar. Paris. 1930. vii, 376 p. fi’ s
33 cm. (Hist. phys., natur., et polit. de Madagascar. v. f.j
Airports in Italy. Washington. 1930. ii, 59 p. 23% cm. [Note: Includes data regarding climate, meteorological stations, etc., at the airports.] (U. S. Bur. for. & dom. comm. Trade inform. bull. no. 721.)
Danaiger Sichtmeseungen. 2. Die acheinbare Flfichenhel- ligkeit einer schwaraen Fliiehe in Abhiingigkeit vom Son- nenazimut bei grossen Sichtweiten. Danzig. 1930. 47 p. figs. 27% cm. (Forschungsarb. des staatl. Observ. Danaig. H. 3.)
Berlin. 1930. 64 p. 24% cm.
Ein Beitrag Bur Klimatologie von Wurttember . Stuttgart. 1930. viii, 138 p. plates. 2334 cm. (gtutt. geograph. Studien. Reihe A. Heft 24/25.)
Radio aids to navigation. 1930. Including details of radio- compase stations, radiobeacons, weather bulletins, storm and navigational warnings, time signals, etc. . . . Washington. 1930. xi, 487 p. plates. 23% cm. (H. 0. no. 205.)
Climate of Sweden. Stockholm. 1930. 65 p. illus. (part col- ored.) 24% cm. (Stat. met-hydrog. anatalt. N: r 279.)
RWe, Heinrich.
Sorge, Emst.
Thost, E. Die Trockengrenze Sudamerikas.
Das Klima des nardlichen Wurttemberg.
U. S. Hydrographic office.
Waueri, Axel.
SOLAR OBSERVATIONS
SOLAR AND SKY RADIATION MEASUREMENTS DURING OCTOBER, 1930
By HERBERT H. KIMBALL
For reference to descriptions of instruments and expo- sures, and an account of the method of obtaining and reducing the measurements, the reader is referred to this volume of the REVIEW, page 26. Table 1 shows that solar radiation intensities averaged close to the normal intensity for October at Washington,
D. C., and Lincoln, Nebr., and slightly below normal at Madison, Wis. Table 2 shows an excess in the total solar radiation
received on a horizontal surface directly from the sun and diffusely from the sk at Washington, New York, Fresno, and La Jolla, and a &ht deficiency at Chicago, hladison, and Lincoln. Skylight polarization measurements obtained a t Wash- ington on SIX days during the month give a mean of 52 per cent and a maximum of 55 per cent on the 4th. At Madi-
son, measurements obtained on four days give a mean of 54 per cent and a maximum of 61 per cent on the 10th. The values for both stations are considerably below the corres- ponding October averages for the respective statione.
The excess was marked at Washington.