242:
103:
33:
289:
127:, the monsoon trough associated with the Australian monsoon reaches its most southerly latitude in February, oriented along a west-northwest/east-southeast axis. North-south-oriented mountain barriers, like the Rockies and the Andes, and large massifs, such as the Plateau of Tibet, also influence atmospheric flow.
318:, or MJO. This mirrors tropical cyclone genesis near these features, as genesis clusters in 2–3 weeks of activity followed by 2–3 weeks of inactivity. Tropical cyclones can form in outbreaks around these features under special circumstances, tending to follow the next cyclone to its poleward and west.
167:
when their temperature gradient becomes minimal, wind surges can cross the equator in oceanic regions and enhance a monsoon trough in the other hemisphere's summer. A key way of detecting whether a wind surge has reached a monsoon trough is the formation of a burst of thunderstorms within the monsoon
334:
are generally reverse oriented. The failure of the monsoon trough, or the ITCZ, to move south of the equator in the eastern
Pacific Ocean and Atlantic Ocean during the southern hemisphere summer, is considered one of the factors causing tropical cyclones to not normally form in those regions. It has
188:
over the continent, and a wind surge will occur at its periphery. Such a circulation which is broad in nature within a monsoon trough is known as a monsoon depression. In the
Northern Hemisphere, monsoon depressions are generally asymmetric, and tend to have their strongest winds on their eastern
196:
poleward and west of the system can enhance its development by leading to increased diverging air aloft over the monsoon depression, which leads to a corresponding drop in surface pressure. Even though these systems can develop over land, the outer portions of monsoon depressions are similar to
310:-rich low level environments, with significant low level spin, lead to a better than average chance of tropical cyclone formation due to their inherent rotation. This is because a pre-existing near-surface disturbance with sufficient spin and convergence is one of the six requirements for
177:
325:
along its periphery will move with a westward motion. If it reverses its orientation, orienting southwest to northeast, tropical cyclones will move more poleward. Tropical cyclone tracks with S-shapes tend to be associated with reverse-oriented monsoon troughs. The
276:. Its abrupt movement to the north between May and June is coincident with the beginning of the monsoon regime and rainy seasons across South and East Asia. This convergence zone has been linked to prolonged heavy rain events in the
122:
in
Australia during February. Its poleward progression is accelerated by the onset of the summer monsoon which is characterized by the development of lower air pressure over the warmest part of the various continents. In the
263:
Since the monsoon trough is an area of convergence in the wind pattern, and an elongated area of low pressure at the surface, the trough focuses low level moisture and is defined by one or more elongated
500:
363:
106:
February position of the ITCZ and monsoon trough in the
Pacific Ocean, depicted by area of convergent streamlines offshore Australia and in the equatorial eastern Pacific
592:
651:
622:
609:
189:
periphery. Light and variable winds cover a large area near their center, while bands of showers and thunderstorms develop within their area of circulation.
762:
763:
Specific
Tropical Cyclone Track Types and Unusual Tropical Cyclone Motions Associated with a Reverse-Oriented Monsoon Trough in the Western North Pacific.
321:
Whenever the monsoon trough on the eastern side of the summertime Asian monsoon is in its normal orientation (oriented east-southeast to west-northwest),
205:
events. Monsoon depressions are efficient rainfall producers, and can generate a year's worth of rainfall when they move through drier areas, such as the
434:
213:
314:. There appears to be a 15- to 25-day cycle in thunderstorm activity associated with the monsoon trough, which is roughly half the wavelength of the
90:. The migration of the ITCZ/monsoon trough into a landmass heralds the beginning of the annual rainy season during summer months. Depressions and
725:
745:
473:
402:
497:
414:
375:
692:
280:
river as well as northern China. Its presence has also been linked to the peak of the rainy season in locations within
Australia.
197:
tropical cyclones. In India, for example, 6 to 7 monsoon depressions move across the country yearly, and their numbers within the
114:
during the late summer when the wintertime surface ridge in the opposite hemisphere is the strongest. It can reach as far as the
558:
94:
often form in the vicinity of the monsoon trough, with each capable of producing a year's worth of rainfall in a matter of days.
71:
exist poleward of the trough. Right along its axis, heavy rains can be found which usher in the peak of a location's respective
371:
331:
327:
49:
315:
143:
of the monsoon trough. Wind surges can lead to this increase in convergence. A strengthening or equatorward movement in the
589:
480:
788:
783:
217:
533:
457:
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can cause a strengthening of a monsoon trough as a wind surge moves towards the location of the monsoon trough. As
610:
A Study of a
Monsoon Depression Bringing Record Rainfall over Australia. Part II: Synoptic–Diagnostic Description.
164:
148:
431:
160:
685:
647:
311:
297:
339:
in the
Pacific, the frequency of tropical cyclones is 2 to 3 times greater than when it lies closer to
37:
36:
August position of the ITCZ and monsoon trough in the
Pacific Ocean, depicted by area of convergent
340:
336:
139:, or spin, with the monsoon trough are normally a product of increased wind convergence within the
124:
119:
115:
722:
742:
664:
273:
241:
176:
144:
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If a circulation forms within the monsoon trough, it is able to compete with the neighboring
636:
Impact of
Southern Oscillation on the Frequency of Monsoon Depressions in the Bay of Bengal.
322:
303:
140:
91:
57:
709:
749:
729:
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596:
504:
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102:
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32:
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is most commonly used in monsoonal regions of the Western Pacific such as Asia and
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520:
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would have characteristics of a monsoon depression throughout their lifetime. The
477:
185:
68:
53:
288:
635:
254:
202:
193:
152:
76:
72:
559:
Effects of the Northeast Monsoon on the Equatorial Westerlies Over Indonesia.
17:
307:
136:
87:
454:
265:
111:
623:
A Diagnostic Analysis of Two Intense Monsoon Depressions over Australia.
277:
258:
246:
206:
156:
64:
56:
showing the locations of minimum sea level pressure, and as such, is a
228:
is the first system recognised as a fully monsoon depression by JTWC.
455:
Chapter-II Monsoon-2004: Onset, Advancement and Circulation Features.
60:
between the wind patterns of the southern and northern hemispheres.
710:
Climate Variability of Tropical Cyclones: Past, Present and Future.
287:
240:
175:
101:
75:. The monsoon trough plays a role in creating many of the world's
31:
534:"Atmosphere - Effect of continents on air movement | Britannica"
110:
Monsoon troughing in the western Pacific reaches its zenith in
577:
SECTION 3. DYNAMIC CONTRIBUTORS TO TROPICAL CYCLONE FORMATION.
634:
O. P. Singh, Tariq Masood Ali Khan, and Md. Sazedur Rahman.
335:
also been noted that when the monsoon trough lies near
302:
A monsoon trough is a significant genesis region for
723:
Tropical Cyclone Formation/Structure/Motion Studies.
67:
winds lie in its equatorward portion while easterly
52:in the Western Pacific, as depicted by a line on a
292:Months of peak tropical cyclone activity worldwide
453:National Centre for Medium Range Forecasting.
521:1.2 Pacific Ocean Surface Streamline Pattern.
8:
441:Ohio State University. Retrieved 2009-03-08.
432:Global Pattern of Surface Pressure and Wind.
652:TWP-ICE Synoptic Overview, 1 February 2006.
214:Regional Specialized Meteorological Centres
571:
569:
567:
449:
447:
515:
513:
352:
397:
395:
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498:Lesson 4 – Seasonal-mean Wind Fields.
358:
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212:Some tropical cyclones recognised by
7:
665:"North Indian Ocean Best Track Data"
474:Australian Broadcasting Corporation
201:increase during July and August of
118:in East Asia during August and the
608:Sixiong Zhao and Graham A. Mills.
419:Severe Weather Information Centre.
180:Monsoon depression near Bangladesh
25:
415:World Meteorological Organization
163:during their winter, normally as
621:N.E. Davidson and G.J. Holland.
332:South Atlantic convergence zones
372:American Meteorological Society
192:The presence of an upper level
741:Joint Typhoon Warning Center.
667:. Joint Typhoon Warning Center
328:South Pacific convergence zone
50:Intertropical Convergence Zone
1:
590:Climate Variability on CNMI.
218:Joint Typhoon Warning Center
224:as a category in 2015, and
805:
295:
252:
135:Increases in the relative
748:19 September 2006 at the
337:20 degrees north latitude
316:Madden–Julian oscillation
728:29 November 2007 at the
483:23 February 2001 at the
284:In tropical cyclogenesis
368:Glossary of Meteorology
40:in the northern Pacific
695:11 August 2008 at the
503:22 August 2009 at the
293:
250:
181:
107:
41:
765:Retrieved 2006-11-26.
752:Retrieved 2006-11-26.
732:Retrieved 2006-11-26.
712:Retrieved 2006-11-26.
708:Christopher Landsea.
699:Retrieved 2008-05-03.
686:Bureau of Meteorology
654:Retrieved 2008-05-03.
648:Bureau of Meteorology
638:Retrieved 2008-05-03.
625:Retrieved 2008-05-03.
612:Retrieved 2008-05-03.
599:Retrieved 2008-05-03.
579:Retrieved 2006-11-26.
561:Retrieved 2008-05-03.
523:Retrieved 2006-11-26.
507:Retrieved 2008-05-03.
487:Retrieved 2008-05-03.
464:Retrieved 2008-05-03.
437:18 March 2009 at the
421:Retrieved 2008-05-03.
405:Retrieved 2008-05-03.
341:10 degrees north
312:tropical cyclogenesis
298:Tropical cyclogenesis
291:
249:after a monsoon rain.
244:
179:
131:Effect of wind surges
105:
98:Movement and strength
35:
789:Atmospheric dynamics
784:Tropical meteorology
595:22 June 2007 at the
460:21 July 2011 at the
48:is a portion of the
172:Monsoon depressions
125:Southern Hemisphere
538:www.britannica.com
496:Dr. Alex DeCaria.
403:The Asian Monsoon.
294:
251:
222:monsoon depression
182:
108:
42:
27:Weather phenomenon
721:Patrick A. Harr.
690:Climate of Giles.
323:tropical cyclones
304:tropical cyclones
274:satellite imagery
151:move through the
145:subtropical ridge
92:tropical cyclones
16:(Redirected from
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761:Mark A. Lander.
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374:. Archived from
364:"Monsoon trough"
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245:View of central
141:convergence zone
58:convergence zone
21:
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378:on 17 June 2009
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743:Typhoon Polly.
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296:Main article:
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209:of Australia.
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84:monsoon trough
46:monsoon trough
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272:when viewing
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270:thunderstorms
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226:Cyclone Komen
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220:(JTWC) added
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199:Bay of Bengal
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120:20th parallel
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116:40th parallel
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18:Monsoonal low
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669:. Retrieved
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588:Chip Guard.
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575:U. S. Navy.
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541:. Retrieved
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519:U. S. Navy.
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380:. Retrieved
376:the original
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134:
109:
83:
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73:rainy season
62:
45:
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29:
186:thermal low
165:shear lines
77:rainforests
69:trade winds
54:weather map
38:streamlines
778:Categories
401:Bin Wang.
347:References
255:Wet season
253:See also:
194:jet stream
161:hemisphere
153:subtropics
308:Vorticity
137:vorticity
88:Australia
82:The term
63:Westerly
746:Archived
726:Archived
693:Archived
593:Archived
501:Archived
481:Archived
478:Monsoon.
458:Archived
435:Archived
168:trough.
112:latitude
278:Yangtze
259:Monsoon
247:Kolkata
207:outback
203:El Niño
159:of one
157:tropics
65:monsoon
671:25 May
543:13 May
382:4 June
149:fronts
266:bands
232:Roles
673:2020
545:2024
384:2009
330:and
257:and
155:and
44:The
268:of
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566:^
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512:^
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355:^
343:.
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79:.
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20:)
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