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Just my experience of observation: hurricanes/cyclones/typhoons in the Pacific Ocean seem to look larger than those in Atlantic Ocean (by looks I mean they occupy more grids in satellite images).

If this is true and if so, what is the reason for this? Is it because the Pacific Ocean has stronger hurricanes/cyclones/typhoons?

Fred
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Gstestso
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1 Answers1

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Typhoons in the western North Pacific ocean can be larger than hurricanes, because the great expanse of ocean water in the Pacific gives them more time and space to develop. Typhoon Tip in 1979 produced gale winds or higher over a diameter of 1400 miles. This is to my knowledge the largest western Pacific typhoon of record (it was also one of the most intense --- near-all-time-record maximum sustained winds of 190 mph, minimum barometric pressure an all-time record low of 25.6 inches of mercury). Typhoon Tip's 1400-mile diameter of gale-force or higher winds is almost double that of the largest hurricanes of record.

Jack Denur
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    Though the reasoning may seem reasonable to many, I don't believe there's any evidence storms grow in size over time by default. Many storms have remained small over long periods of time. Storm (at least in the Atlantic basin) usually become largest when interacting with mid-latitude systems. So though your example of Tip is certainly helpful, I don't believe the conclusion you come to is valid. I'm holding off an answer until I come across some more quantitative values – JeopardyTempest Jun 20 '17 at 18:17
  • I've always assumed the Tip information was solid. But as I looked into when Tip was at maximum size (to see if it fit duration arguments), it seems that the information is less precise than we've always believed. http://journals.ametsoc.org/doi/pdf/10.1175/1520-0493%281980%29108%3C1915%3AAAOSTT%3E2.0.CO%3B2 indicates > 1100 km radius of 15 m/s. https://en.wikipedia.org/wiki/List_of_Atlantic_hurricane_records#Largest_in_diameter shows quite a few Atlantic storms over that radius. And https://www.youtube.com/watch?v=Q_H6zRbIuz4 doesn't look too different in hemispheric satellite either. – JeopardyTempest Jun 20 '17 at 18:22
  • Indeed, Tip's greatest size was October 13-17, which is 9-13 days after formation. Many storms in the Atlantic last that long, most recently Gaston and Nicole last season. So while duration may seem at first glance to be a reasonable explanation, it appears more complex than that :-) – JeopardyTempest Jun 20 '17 at 18:25
  • Thank you for the paper about Typhoon Tip. The radius of 1100 km = 700 miles for gale force or higher winds in Tip corresponds to a diameter of 2200 km or 1400 miles. Of course small tropical cyclones can develop in large tropical ocean basins such as the western Pacific, but big ones such as Typhoon Tip cannot develop in small tropical ocean basins. Large tropical ocean basins provide the time and space that are NECESSARY BUT NOT SUFFICIENT conditions for big tropical cyclones such as Tip to develop. Of course requirements in addition to than large ocean basin size must also be met. – Jack Denur Jun 21 '17 at 00:19
  • Oye, you definitely got me there, silly error in my part, radius vs diameter, ugly to make such a mistake. That said (if the wiki list is valid) looks like Olga 01 apparently had over 800 mi gale diameter despite only traversing about 1000 miles total, so declaring a large storm cannot develop in a small basin doesn't sound reasonable to me. And appears storms can last about 10 days in all basins. In the end it sounds like the questioner is asking about typical size rather than outlier size, so the discussion is moot anyways. – JeopardyTempest Jun 21 '17 at 01:39
  • If the basin is TOO small then a large storm may not be able to develop even if a small one would be able to. A minimum size for the basin, not necessarily as big as the western Pacific basin, does seem to be a necessary but not sufficient condition for a big storm. – Jack Denur Jun 21 '17 at 06:54
  • The correlation coefficient for the relation between tropical cyclone size and basin size would not be anywhere near 1, but it would be greater than 0. There is at least a small positive correlation. A tropical cyclone the size of Typhoon Tip probably could not form in the Gulf of Mexico --- if it tried to form much of the circulation would be over land and thus would entrain dry air, weakening the cyclone. Probably at a minimum the basin size should at least equal the diameter of gale-force winds. – Jack Denur Jun 22 '17 at 08:13