indeed, tne circulation attainine typhoon intensity in a matter
of 24-36 nours, frou the time of first appearance of the singu-
"lar points (waicn marks tne inception of tne definitive vortex.)
e)
stable vortex.
sSvoner or liter tne vortex reaches a
stage
where it deepens no more and moves witnout mucn change of
intensity for long distances.
table vortices seem to be
of every degree of intensity from feeble circulations barely
detectable 43 sue. in tie pré-sure field up tothe most destructive typhoons.
vicissitudes;
All stable vortices seem subject to tne same
they may move westward for long distances, or may
recurve into iilgner latitudes.
by prolon,red passage over land.
TIney appear to be wuch weasened
so long as they sre on the
westward track they move unifor.ly at a speed between 10 and
15 xnots (this 2lso is the speed range of the stable waves)
but near,
ut and after recurvature the speed of movement may be
@rratic.
In otner words the known characteristics of ty, noons
(excert for intensity) seem to apply to stable vortices in
general,
indeed a typhoon is simvly a vortex th.t his attained
sufficient intensity to be of practical interest to man.
it will be obvious to zou that I have merely described the
appearance of typical streamline maps at low levels in one small
area in tne certral Pacific and taat for only a short period in
1946.
WNevertaeless even tnis liiteu infornation tirows a flood
of lignt on many vrobleus that beset us in tue days when we relied
on inidecuute surface pressure maps.
33
5001b21
First, we can tive up the