Archive for the climate change Category

Hurricanes of August 2014

Posted in climate change, Seasons with tags , on August 9, 2014 by marksun

Hurricane Iselle was a near thing.  Hawaii watched with anxious anticipation, hoping for the best as the  Category 1 980 mb storm barreled straight into the eastern-most coast of the Big Island late Friday night August 8 and continued through Saturday.   I’ll just relate impressions from talking to hams and friends via facebook and twitter.  For real news, it is all over the papers and the internet.  In Puna up through Volcano, winds were scary and severe, knocking  down trees, rattling roofs and walls.  The rain affected Puna, Hilo, Hamakua, and the Kohala mountains eastern exposures, Kau and perhaps some wrap around to S Kona.   Folks I heard in the Kailua Kona, deep in the lee of Mauna Loa and Hualalai – the third large volcano on Hawaii, reported little by way of rain and wind.   Hilo experienced strong winds in gusts, fallen trees everywhere, rain, a broad and disruptive power outage in Puna and Volcano, Waimea, and the theft of a Red Cross pickup truck.  Significantly, landline phone, cellphone service was lost – there may still be outages here and there now 48 hours later.  My family on the Big Island reported no damage to our homes, flood waters contained within the banks of the stream in our place in Waimea.

The very interesting aspect of this event was that Mauna Kea and Mauna Loa,  broad 4000+ meter high volcanic shield volcanoes effectively  blocked the lower level airflow within the hurricane, and apparently caused the system to unravel.  Hard to say exactly what other factors played a role – the forecast models ( these are giant computer programs to run weather simulations based on real data ) predicted the storm intensity decline – I do not know if the island effects were part of those models) .    The satellite shots show few visible traces of a storm center once the region of central pressure moved west past Hawaii Island.   A tropical storm circulation of greater than 1000 mb central pressure continued tracking west.

One can hear  “noise crashes” caused by lightning on radio receivers.  During this storm I heard some and other  hams noted “hearing” lighting as well.  Overall it seems lighting did not affect us much.  I did hear thunder in the distance, and some folks did report it.  I heard no reports of tornadoes, a fearsome prospect and by-product of hurricane related thunderstorms.  I heard a first hand account of tornadoes associated with Hurricane Iniki on Kaua’i. This leads me to speculate that tornadoes or other vortice – like winds  may have played a greater role in storm damage  on Kaua’i than is generally recognized.

Ham radio operators on Maui reported generally remarkably mild conditions – wind here, rain there.   On Oahu, winds came up and downed trees in the Pali area, and certainly all over the place.  Trees come down at random in just about any kind of wind greater than the average, but we can credit these casualties this storm.   At my place in Aiea, 400′ up in the ridge above Pearl Harbor,   the wind speed varied greatly with periods of gusts of 25k or so, maybe an occasional higher burst.   In my rain gauge, total event rainfall was just over 1″.

A second storm, Julio, is tracking WNW and if this course persists will pass to the North as a tropical storm.  This event is unlikely to have as significant an impact as Iselle – it is significantly farther north and distance matters.    The uncertainty for the past several days is the uncertainty inherent in predicting the course of nature.  However the computer models used by the National Weather Service are “pretty good” in my opinion and incorporate a great deal of information based on an unprecedented accumulation of scientific knowledge.  Precision leaves a lot to be desired, but the effects of  randomness pervade all forces of nature, and computer models have not tamed the element of chance.

OCTOBER 2014.  Ana –

15 Oct 2014.  This storm materialized out of the ITCZ cloud band on Sunday with a threatening .

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