Why So Many Hurricanes?Added : Friday at 14:25 You may be thinking, "It's been a rather quiet start to the hurricane season, why have they all started coming along now?"
It's a pretty good question. Of course, you are bound to get the tentative links to climate change, global warming, brexit etc etc. But, the actual reason is far more boring/interesting (delete as applicable).
Here is the tropical Atlantic at the moment :-
You can see Humberto at the top and Jerry at the bottom. Here is the Pacific :-
Three tropical storms in that one. The reason is down to a couple of things which happen at this time of the year. First of all, check out the ITCZ (Inter Tropical Convergence Zone) at the moment :-
You can see this as the band of thunderstorms across Central and Eastern Africa. Note that it resides in the 10-20N latitude lines. This is important as it's known as the "sweet spot" for hurricane development. It's far enough away from the Equator to allow the Coriolis effect to start some spinning, but not too far. We also have water at its warmest off the East coast of Africa at this time of the year and finally, if you look at the Northern edge of the ITCZ you can see the AEJ or Africa Easterly Jet. This creates "ripples" in the ITCZ coming off the East coast of Africa which in turn creates Tropical Waves.
September is and always has been the peak of the Atlantic Hurricane Season, worth bearing in mind if you are planning holidays in the Caribbean and Southeast USA.
Over the next month or so, the ITCZ will continue to move South and away from the sweet spot of development as the hurricane season draws to a close.
So, there you have it. You can blame the ITCZ, earths tilt, warm oceanic waters and the African Easterly Jet for the sudden increase in hurricane activity. Of course, you can still blame Brexit if you want, but you'll be on your own with that one.
METEOROLOGIST : MARSH |