CLIMATE—THE SYNTHESIS OF WEATHER 
down the climate of a particular locality with a facility 
which might not be available to a statistical climatolo- 
gist. It is true the forecaster had to contend with diffi- 
culties not least of which was that he knew too much. 
To him, intent on his daily synoptic charts with their 
infinite diversity, it was not easy to generalise without 
so much detail as to mar the climatological picture. 
But it could be done, and it was possible thereby to 
convey a far more graphic picture than would be pos- 
sible from the consideration of any number of statistics 
and normal charts. 
With the coming of World War II the need for de- 
seriptive climatic information became more pressing, 
and this technique for the use of synoptic charts and 
daily observations was developed in Britain in a series 
of manifolded reports on the climate of various regions. 
In these the attempt was made to describe the effects 
which were likely to be produced in the neighbourhood 
of different topographic features when certain air 
streams impinged on them, the object being to convey 
to the reader the idea of climate as a synthesis of the 
daily weather as opposed to the rather static presenta- 
tion given by a conventional write-up of the normal 
maps. 
One great advantage of this method was that the 
climatic description was readily assimilable for fore- 
casters, so that a forecaster arriving in a new region 
could have a broad outline of his forecasting problem 
before him from the outset. 
An example of this presentation is the description of 
the climate of Southeast Asia by Hare [1]. From the 
examination of whatever weather maps could be ob- 
tained or constructed—and in this the Daily Synoptic 
Series, Historical Weather Maps [32] was of the greatest 
' value—Hare isolated certain air flow patterns to which 
the weather map tended to return if it were disturbed, 
and he identified certain positions of the quasi-perma- 
nent fronts to which they too returned. Thus he was 
able to describe the climate associated with the flow 
pattern, particularly in the case of the winter monsoon, 
in some detail, and moreover to emphasise what de- 
partures could be expected with changing synoptic 
situations and how those situations once more reverted 
to the standard pattern. At the same time he drew 
attention to the characteristics of the air masses, using 
a local modification due to Huang [15]. The known high 
frequency with which the fully developed winter mon- 
soon held sway served to guide the reader as to what 
climate to expect, and the simplification led him to a 
concept of change within a repeating pattern. It is true 
that the simplification, like all simplifications, masked 
some degree of detail, but in climatology some detail 
must inevitably be lost and the generalisation of 
weather into this climatic representation gave some- 
thing that was easily assimilated. 
_ The season of the summer monsoon was less easily 
generalised, but here too on the basis of the synoptic 
charts it was possible to establish a broad outline of the 
repeating patterns of the air streams. The transition 
periods of spring and autumn were treated in a similar 
way. 
971 
After Hare’s work had been produced, Lu’s ‘““Winter 
Frontology of China” [24] was published in the Bulletin 
of the American Meteorological Society. Lu’s account was 
on a more elaborate scale, but was essentially a state- 
ment of climate in terms of air masses and fronts. It 
bore out Hare’s analysis to a high degree and the com- 
parison is interesting in that it shows how much can be 
achieved in this type of representation by one who has 
no greater acquaintance with the country of which he is 
writing than is afforded by a series of weather maps. 
At different dates from 1939 onwards British reports 
on similar lines were prepared for most of the theatres 
of war. They were manifolded, but the number of copies 
was limited. 
To impress on the reader the variability of the 
climate, some of these reports included diagrams which 
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8 WAVES (ARROW POINTS UP OR. DOWN 
ACCORDING AS WAVE PASSED TO 
NORTH OR SOUTH. NO ARROW MEANS 
WAVE PASSED DIRECTLY OVER.) 
KEY? FcoLD FRONT 
| warm FRONT 
[§ THUNDERSTORM 
TYPE OF AIR MASS 
= 
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Ps DIRECT POLAR SIBERIAN Pp POLAR PACIFIC 
NPs MODIFIED POLAR SIBERIAN Tp TROPICAL PACIFIC 
(ASTERISK INDICATES E EQUATORIAL 
OVERLAND TRAJECTORY) 
Fig. 1—Daily weather at Dairen, Manchuria, for August, 
October, and December, 1929. 
gave the daily observations of a year ranged out on a 
single sheet of paper. An extract from one such diagram 
is shown in Fig. 1 in which the months August, October, 
and December, 1929 are illustrated for Dairen in Man- 
