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This article was written some days ago but traces the development of Haiyan and makes the connection with the warming ocean.
Abnormally
Hot Pacific Ocean Explodes Haiyan into 195 mph Monster — Possibly
Strongest Storm On Record
7
November, 2013
Perfect
symmetry. It’s a meteorological term that describes the structure
of a classic hurricane. A perfect doughnut-shaped eye wall filled
with clouds ranging from 50,000 to 60,000 feet height in all sectors
circling swiftly around a deep and tiny central eye. In a textbook,
the term perfect symmetry is innocuous. In an actual hurricane, the
result is horrific.
As
Haiyan did the seeming impossible and became better organized late
Wednesday and early Thursday, a perfectly symmetrical eye wall
developed over waters in excess of 80 degrees (F) and in an
atmosphere boasting little or no wind sheer. By noon on Thursday,
this perfect structure allowed more efficient evacuation of air
through a deep and perfectly clear eye, pulling winds of ever-greater
strength through its encircling storms. Explosive winds of a strength
equivalent to a strong tornado, at 190 mph (US Navy showed 195 mph at
2 PM EDT), blasted around the storm’s center as its minimum
pressure fell to 904.5 millibars — 40 millibars more intense than
Hurricane Sandy (latest estimates show pressures as low as 858 mb,
the lowest ever recorded).
Haiyan’s
wind field is now the strongest measured in any hurricane since at
least 1980, when Hurricane Allen briefly exploded to 190 mph
intensity. The difference between Haiyan and Allen is that the
storm’s fury was mostly vented on the open waters of the Caribbean
and Gulf of Mexico. In contrast to Allen, it increasingly appears
that Haiyan will peak in intensity right before impacting millions in
the Philippines. Given the more recent measures, it is possible that
Haiyan has left even Allen behind, surpassing even the strength of
the strongest storms ever recorded — Camille and Tip.
It
is difficult to overstate the danger of this situation. Haiyan is now
more powerful that Andrew and Katrina. It is likely a rival of even
Camile’s amazing intensity. All interests in the path of Haiyan
should rapidly respond to any evacuation orders as this is an
extraordinarily dangerous and powerful storm.
Haiyan
is currently located about 100 miles east of the Philippine
archipelago’s eastern edge. It’s very rapid forward motion of 25
mph will bring it over land within the next 4 hours. Over the next
day, it should continue to churn over or near numerous Philippine
islands before exiting the archipelago late Friday. Current forecasts
predict Haiyan will maintain category 5 strength for much of this
period, dropping to 150 mph, a strong category 4, as it exits the
Philippines. Over the next few days, Haiyan is then expected to
threaten Vietnam or southeast China as a strong category 2 or
category 3 storm. (Haiyan made landfall near Guiuan at about 4 PM
EST).
The
above Modis shot shows Haiyan strengthening early Thursday morning as
it began its final rush toward the Philippines.
Hot
Ocean Waters in the Western Pacific Spawn 81 Cyclones for 2013
Very
hot ocean waters ranging from 1 to 5 degrees Celsius above the
1980-2000 average throughout much of 2013 have spawned numerous
severe weather events throughout the Western Pacific. On January
1rst, the first tropical cyclone of 2013 formed, not waiting even a
day to begin what would prove to be an explosive, record season.
Throughout
2013, cyclones continued to form so that by November 81 cyclones had
ripped through this region of the Pacific. Of this number, 38 storms
were tropical depressions, 30 were tropical storms, and 13 were
hurricanes. Four of these hurricanes were category 5 monsters.
During
late summer a powerful tropical storm combined with a monsoonal flow
to drench Manila in record rainfall, flooding much of the city.
Other strong storms also impacted the Philippines, setting off
landslides and numerous record flooding events. Haiyan is just the
most recent and strongest example of a series of powerful storms
impacting the vulnerable island chain.
Hot
Pacific Ocean waters in a region north and west of the Philippines
were also implicated in a major heatwave that resulted in scores of
deaths throughout China, Korea, and Japan. This unprecedented ocean
heat dome resulted in highest ever recorded temperatures with records
being shattered consecutively, day after day, for up to two weeks in
some locations.
Ocean
heat temperature maps seem to be painting a bulls eye on the Western
Pacific. And, for 2013, large swaths of water in this area continued
to boast temperatures in excess of 90 degrees (F). This abnormally
hot water enhanced evaporation and fueled various extreme weather
events including the massive spate of tropical systems as well as the
record floods seen in the Amur region of Russia and China.
As
with many other extreme warming events, the regional warming seen in
the western Pacific cannot be entirely separated from an ongoing
global warming trend. August of 2013 boasted the world’s hottest
ocean temperatures ever recorded. September 2013 tied 2005 for the
hottest September on record. Extreme heating provides more energy for
storms, droughts, and other extreme weather events. For each degree
Celsius of global temperature increase, the hydrological cycle (the
rate at which water evaporates and precipitates) increases by around
7 percent. Such an increase makes droughts more extreme even as it
provides added heat and moisture fuel to increase the intensity of
storms.
Many
scientists are now attributing the increased strength of storms over
the past decade and becoming particularly intense in recent years, to
the ongoing and amplifying impacts of global warming. In this case,
scientific conservatism is slowly giving way to both the observed
impacts of global warming and a lengthening string of increasingly
intense events that continues unabated.
As
seen in the above seasonal temperature graph, a large area of ocean
surface waters have remained at or near 90 degrees (F) for an
extended period. These temperatures are about .5 to 2 C (1-3 F) above
the climatological average seen from 1980 to 2000. They are about 1-3
degrees C above averages seen in this region during the 1880s, as
human greenhouse gas emissions began to ramp up. This pool of very
hot water is enormous, larger than the land area of Australia, and it
has continued to provide fuel for powerful weather events over most
of the past year. Since hurricanes can form in water temperatures
exceeding 75 degrees (F), this expanding warm water region is
resulting in a near continuous energy potential for the development
of these storms. And this hot pool of water will continue to warm as
human greenhouse gasses continue to ramp up, likely eventually
resulting in a time when the Hurricane season, at least for the
Western Pacific, never comes to an end.
UPDATE:
Intensity
observations, all now based on satellite, show no abatement of
Haiyan’s impressive fury. Cloud heights, symmetry and lightning
frequency in the eye wall still show an extraordinarily powerful
storm. Current estimates have Haiyan maintaining 190 mph maximum
sustained winds with gusts to 230 mph.These maximum wind totals are
comparable to that of a powerful tornado, with the strongest
hurricane wind field extending out 50 miles from Haiyan’s center.
Analysis
at Weather
Underground by Dr. Jeff Masters
raises the possibility that Haiyan may now even rival Super Typhoon
Tip’s record minimum central pressure of 870 millibars. If this
were to case, Haiyan would be the most powerful storm on record.
Since we have no direct observations, however, there is no way, as
yet, to confirm this analysis. At the very least, it is likely that
Haiyan rivals the most powerful storms on record since at least 1969
— Camille, Tip, and Allen.
Projected
wind and rainfall intensity is provided by NOAA below:
Landfall
storm surges of 15-20 feet with 15-25 wave heights are expected. Sea
surface temperatures at 85 to 86 degrees (F) and near zero wind shear
in the region are conducive for continued extreme storm intensity.
Rainfall
totals are expected to exceed 8 inches along the path of travel and
50 miles out from the center. Consistent inundation with heavy
rainfall events over recent months, including a recent tropical
depression, have left the ground in areas along Haiyan’s projected
path saturated and very vulnerable to flooding. So high risk of flash
floods and landslides remain a serious threat. Expected rainfall
totals are somewhat suppressed by Haiyan’s fast forward motion at
25 mph to the WNW. But rainfall in excess of 2 inches per hour is,
nonetheless, likely to result in extreme flood risk.
Emergency
management officials are urging millions to evacuate regions closest
to Haiyan’s path. Manilia is expected to be grazed by the storm,
experiencing tropical storm force winds and rainfall totals around
4-8 inches. Any deviation in Haiyan’s expected path could
drastically change these forecasts.
Haiyan
is more powerful than hurricane Megi, a 2010 storm that boasted 170
mph winds and resulted in hundreds of millions in damages and a heavy
human toll.
(Most
recent water vapor shot. Image source: NOAA)
UPDATE:
Haiyan
is now making landfall on the Guiuan Peninsula a coastal community
with a population of 48,000. Preliminary pressures in the area are
showing 992.5 mb. The storm’s strongest winds are now starting to
impact the Eastern Philippines with Leyte, Tacloban, and Borongan in
the bull’s eye. A wind speed measure one hour ago showed sustained
winds in Guiuan at 96 mph. Winds in the area are likely much stronger
now. Very tough 18-24 hours ahead.
(Image
source: NOAA)
UPDATE:
Unconfirmed
pressure reading at 889 mb via handheld near Guiuan at 5:01 AM. US
Navy data showing 196 mph storm with 235 mph gusts and maximum
significant wave heights of 50 feet 6 hours ago (H/T to Colorado
Bob).
UPDATE:
Preliminary
Satellite estimate shows Haiyan bottomed out at 858 mb minimun
central pressure. Source: WGN Chicago. If true, this would make
Haiyan the strongest storm ever recorded. Weather station in Guiuan
no longer reporting. In all honesty, I wouldn’t be surprised if
that little spit of land is all under water now.
The
sun’s up. So you might want to take a look at this live shot of
Boracay which lies almost directly in the path of this storm, which
is still over 100 miles away from the camera’s location:
http://www.earthcam.com/world/philippines/boracay/bolabogbay/
UPDATE:
NOAA
reports that deep, warm water helped fuel Haiyan’s record
intensity:
The
intensification of Super Typhoon Haiyan is being fueled by “ideal”
environmental conditions – namely low wind shear and warm ocean
temperatures. Maximum sustained winds are currently at 195 mph, well
above the Category 5 classification used for Atlantic and East
Pacific hurricanes.
Plotted
here is the average Tropical Cyclone Heat Potential product for
October 28 – November 3, 2013, taken directly from NOAA View.
This
dataset, developed by NOAA/AOML, shows the total amount of heat
energy available for the storm to absorb, not just on the surface,
but integrated through the water column. Deeper, warmer pools of
water are colored purple, though any region colored from pink to
purple has sufficient energy to fuel storm intensification. The
dotted line represents the best-track and forecast data as of 16:00
UTC on November 7, 2013.
The
extra depth of the warm water added further fuel for intensification
because cyclones tend to churn up the water, bringing cooler water up
from the deep ocean. This action tends to cause the storm to weaken
over time, as it brings up cooler and cooler water or as it crosses
the paths of other storms. But if water at depth is warmer, one key
factor that can weaken storms is removed.
Yet
more evidence of global warming at work. Read more here:
http://www.nnvl.noaa.gov/MediaDetail2.php?MediaID=1452&MediaTypeID=1
(Oct 31 to Nov 31 Pacific Ocean Heat Intensity in Joules. Image source: NOAA)
UPDATE:
Yet
another ‘perfect storm’ satellite shot of Haiyan. This one
showing amazing stadium effect at landfall.
(Image
source: MTSAT)
UPDATE:
Satellite
imagery shows Haiyan passing into the central Philippines. Cloud tops
are warming somewhat as the storm is disrupted by the surrounding
land mass. Overall, this shows weakening and maximum sustained winds
are now estimated to have fallen to around 185 mph or less with
pressures rising to around 895 mb. Still a very intense storm, but at
least one that is now showing some weakening.
UPDATE:
Haiyan
exited the Philippines today as a 155 mph category 4 storm. Damage
reports are now mostly sporadic. Currently, few have been able to
access the hardest hit areas due to fallen trees blocking roads. It’s
now around 1 am in the Philippines, so assessments of hardest hit
regions will likely begin to trickle in later today. Most likely, the
areas of highest impact were located within the eyewall itself — a
10-20 mile region directly surrounding the eye — and in areas near
or close to where the storm made landfall. At its most intense the
storm was estimated to have 195 mph maximum sustained winds. As the
storm crosses the coast, this wind field tends to destabilize and
form micro whirls which act in a manner similar to tornadoes. If the
wind field was as strong as estimated, it is likely that tornado-like
damage was inflicted directly in the path of the storm, especially
within a 10-20 mile zone in the storm’s right-front quadrant.
Again,
as yet, there have been few reports from the hardest hit regions due
to difficulty accessing those zones and we will have to wait until
daylight before gaining a more accurate assessment of the damage.
Forecasts
are currently calling for Haiyan to slowly weaken as it moves over
cooler waters. That said, it appears the storm will make landfall as
a Category 2 storm in the region of Vietnam and Southeast Asia. There
it is likely to emerge as a major rain event.
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