The tropics and summer heat share the spotlight this week, as temperatures peak in the northern hemisphere and cyclone season heads into the stretch drive.
And for intrigue, we have the travels of an apparent piece of a long-missing airplane to explain.
Let’s go Around The World.
Indian Ocean: Two-B or not Two-B; Cyclone Komen Inundates Parts Of Bangladesh And India
A minor tropical cyclone with the Shakespearean name Two-B drifted south from near Kolkata, India (yes, it used to be Calcutta) wandered over the Bay of Bengal (no, there are no tigers there), and made landfall as a minimal tropical storm named Komen on Friday near Chittagong, Bangladesh, at the mouth of the Brahmaputra River.
Wind was not much of a threat, but rain — over 40 inches of it — was. At least 81 people were reported killed as the storm moved very slowly back towards India, also affecting Myanmar to its east.
India, Bangladesh, and Myanmar are accustomed to monsoon rains at this time of year. But when the precipitation is exacerbated by a cyclone, even a weak one like Komen, the water overwhelms the capacity of the drainage to handle it.
Powerful cyclones are relatively rare in the Indian Ocean due to its separation into the Arabian Sea and the Bay of Bengal by India. Storms don’t have the length of an ocean like the Atlantic or Pacific in which to gather steam.
However, cyclone development in the Bay of Bengal is not uncommon; storms often form on the ‘monsoon front,’ and make landfall in India, Bangladesh, or Myanmar.
In 2014, there were five tropical cyclones in the Bay of Bengal, one of which, Hudhud, reached category two strength before making landfall in India. The death toll from Hudhud was over 100.
Atlantic Ocean: Cape Verde Hurricane Season Underway
Most major Atlantic hurricanes originate in the eastern Atlantic near the Cape Verde Islands. The water has become marginally warm enough in that area to support cyclone formation, so the National Hurricane Center will increasingly focus on easterly waves coming off Africa.
The first such wave with any prospect of development entered the Atlantic last week but really never had a chance. Over the marginally-warm-enough water, it petered out when it encountered hostile upper level winds in the middle of the ocean.
Eastern Pacific Ocean: Hurricane Guillermo Threatens Hawaii
Hurricane Guillermo was born in the warm waters southwest of Mexico and developed into a hurricane on Friday.
The most recent forecast calls for Guillermo, now a tropical storm, to pass north of the Big Island on Wednesday.
Great surfing will probably be bigger news than any damage from this storm.
Western Pacific Ocean: Typhoon Soudelor Takes Aim At Taiwan
With winds of 160 miles per hour, Soudelor has now reached Super-Typhoon strength (150 miles per hour or greater).
Soudelor is headed for Taiwan, and the eye is forecast to pass directly over Taipei Friday night, at which time the winds will still be over 100 miles per hour.
So far this summer, the typhoon trajectories have favored a more northerly path than the ones that brought destruction to the Philippines the last two summers.
Heat Waves Continue And Expand
Decoded Science has named the weather patterns that have produced record heat in the northwest and southeast US, Westzilla and Hotzilla respectively. Now we have the worst of both, as the patterns seesaw back and forth. Westzilla has returned to Seattle, Spokane, and Portland this week, with high pressure and a warm cap in the middle of the atmosphere. But the low pressure in the eastern US that accompanied the first episode of Westzilla is very modest, leaving Houston, Texas and Columbia, South Carolina to bake in triple-digit temperatures.
The heat coupled with drought has led to an early start to the wildfire season, normally confined primarily to the fall. In most of the west, wildfires are at record numbers for this point in the season. Undoubtedly this will not be the last time this subject is mentioned in Weather Around The World.
The forecast calls for the pattern to revert to Hotzilla, a zonal (westerly) flow across the northern states this week, which will bring cooling to the northwest; but no relief from the heat is in sight for the south.
The Spanish heat wave goes on, with temperatures climbing to around 100 every day. There are some indications that in about a week the temperatures will moderate into the upper 80s.
The zonal jet stream across Europe, responsible for the Spanish heat wave, has also brought record heat to Israel and the Middle East. One-day electricity use in Israel made a new all-time high on Sunday, surpassing the summer record posted during the heat wave of July, 2012.
Interestingly, the old all-time record was not the one from 2012, but from this past winter when a cold spell required record electricity use for heating on January 12, 2015.
These extremes of heat and cold are in keeping with trends elsewhere, and are consistent with the forecasts for global warming.
Part Of A Wing Of MH370 Washes Ashore
Investigators are 99% sure that the piece of debris found on Reunion Island in the Indian Ocean is from the missing airliner that vanished nearly a year and a half ago. Reunion is 2500 miles from where the plane most likely crashed, but the wing flap could not have followed a straight path from crash to debris site.
The search area for the plane is off the southern tip of Australia, in the 40 degree latitude band known locally as the roaring 40s. Storms frequent these seas, and the winds are almost interminably westerly.
Meanwhile, closer to the equator, the easterly trade winds dominate. These two flows set up an anticyclonic whirl around the Indian Ocean, similar to the one in the Atlantic that includes the Gulf Stream (the flow in the northern hemisphere is clockwise).
So this piece of the aircraft must have traveled nearly three-quarters of the way around the Indian Ocean gyre. Let’s see if the numbers make sense:
The circumference of a circle with a diameter of 3,000 miles (the approximate diameter of the Indian Ocean) is about 9,400 miles (3,000 times π, which is about 3.14). Three quarters of 9,400 is about 7,050 miles. The plane has been missing for 514 days, so it would have had to travel at a speed of approximately fourteen miles per day, or a little over one-half mile per hour. This is well within the bounds of oceanic speeds, as currents often reach several miles per hour. Given time for the debris to be caught in eddies, the timing seems about right.
Summer Rolls On
While tropical cyclone season ramps up, it’s the hottest time of the year in the northern hemisphere. How hot is it where you are?
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