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Black Sea storm causes ecological disaster; powerful Bay of Bengal cyclone forming

By: Dr. Jeff Masters, 3:25 PM GMT on November 12, 2007

At least five ships sunk and five others ran aground yesterday during a fierce storm that swept through the Black Sea, by Russia and the Ukraine. Five sailors drowned and as many as 17 others are missing. The Volganeft-139, an oil tanker loaded with nearly 1.3 million gallons of fuel oil, sank in the Kerch Strait between the Black Sea and the Sea of Azov, dumping over 1/2 million gallons of fuel into the water. The oil spill is a major environmental disaster for the area, and will foul local shores for years to come. The spill is about 1/20 the size of the massive Exxon Valdez oil spill of 1989.


Figure 1. Visible image from the NOAA-18 polar orbiting satellite from Saturday, November 10, 2007, at 11:21 GMT. An "L" marks the center of the developing storm that would move over the Black Sea and sink or ground ten ships. The storm formed at the tail end of a cold front to its north. Image credit: University of Bern, Switzerland.

The storm that sank these ships was an unusually powerful one for the Black Sea. The storm formed over the Mediterranean Sea along the tail end of a very strong cold front. This front was the same cold front that pushed through the North Sea on Friday, bringing winds near hurricane force, flooding in southeast England, and a storm surge over 10 feet high to the coast of the Netherlands. The new storm fed off the relatively warm waters of the Mediterranean and pushed eastward across Greece and Turkey, intensifying to 980 mb as it struck the Ukraine's Crimean Peninsula late in the morning Sunday. Simperopol, Ukraine, on the tip of the Crimean Peninsula, measured sustained winds of 54 mph, gusting to 72 mph, on Sunday afternoon. The pressure bottomed out at 980 mb. Kerch, Ukraine, on the west side of Kerch Strait, recorded sustained winds of 45 mph and a minimum pressure of 988 mb as the storm blew through. On the other side of the strait, in Anapa, Russia, sustained winds of 47 mph, gusting to 65 mph were observed. Waves up to 18 feet high buffeted the waters in the Kerch Strait. This was too much for the Volganeft-139, which was designed for river travel.

The enclosed nature of the Black Sea can produce very steep waves. According to Holquist et al. (2002), steep, short-period waves can be particularly hazardous to large ships, especially when the waves exceed 5 meters (16 feet) in height. The height of waves depends on the wind speed and the fetch or distance over which the wind blows. Also important is the degree atmospheric stability near the surface. A warm ocean with very cold air aloft will produce an unstable atmosphere with very tall turbulent eddies that will mix down the stronger winds that occur aloft. This instability peaks in November, when the air-sea temperature difference is at its greatest.

References
Hultquist, T.R. M.R. Dutter, and D.J. Schwab, "Reexamination of the 9–10 November 1975 “Edmund Fitzgerald” Storm Using Today’s Technology", Bulletin of the American Meteorological Society, May 2006.

The NASA Natural Hazards team has posted a nice satellite image and description of the storm.

Tropical Update
None of the reliable computer forecast models are predicting tropical cyclone formation in the Atlantic for the next seven days. I'll have a complete analysis of the outlook for the remaining 2 1/2 weeks of hurricane season later this week.


Figure 2. Tropical Cyclone Sidr at 5:30am EST 11/12/07. Image credit: Navy Research Lab, Monterey.

Tropical Cyclone Sidr is headed northwards towards a landfall in Bangladesh or India late this week, and may intensify into a Category 2 or higher storm. The Bay of Bengal has seen the world's deadliest tropical cyclones, and November is one of the region's most dangerous months. On November 12-13, 1970, a Category 4 cyclone struck Bangladesh, causing the greatest tropical cyclone disaster in world history. An estimated 350,000-550,000 people died when a devastating 34-foot storm surge funneled northwards through the Bay of Bengal into Bangladesh. The path of Tropical Cyclone Sidr beyond Wednesday is highly uncertain, with the NOGAPS and ECMWF models taking the storm northwards over a region of high oceanic heat content and into Bangladesh. The GFS model turns Sidr westwards, over a region of low oceanic heat content, into the east coast of India. Wind shear is about 10 knots over the storm, and is expected to remain 10 knots or below for the next three days. Recent satellite observations suggest that Sidr is already of hurricane strength, and may be intensifying rapidly.

Jeff Masters

Winter Weather

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

yeh,storms like that are very rare.
hey folks! I remember that storm, too. We only got about 6" in B-lo but the whole eastern seaboard was unindated. It was refreshing for us to see someone else get pummeled...
LOL Lake :)

Well you could be seeing it in the next couple of days. NW winds across the Lakes.
In weather,timing is everything,all the ingredients for that storm came together at the same time.
I count it in my top 3 weather experiences. Getting to see the cold and warm sector. Surpasses several notable hurricanes on my list! Gotta go BBL!!!!!!
NW you say? So the lake shadow will protect me!
LOL,shadow,one should never take glee in someone else getting pummeled,in weather you may be next in line.
Yea Lake NW then West. Looks like the southern shores off erie and ont thursday night into friday the the eastern shores of both on friday into friday night
The thing is that we always get pummeled...Those feelings arose after about 90-100 inches that had already fallen on us that year. So we are and were always next in line.
Morning folks...so Sidr is a CAT4, Calcutta is about to get put through the spin cycle and there's another feature north of Australia.

Domestically, there's the beginnings of a storm for the NE...that's one every weekend...did you order this weather Bone? LOL

Latest Sidr pic:

Westerly winds will give me some snow. SW is when the ribbon bands go right over my house. Some times the wind occillates from NW to SW...in those instances the snow keeps coming back. Thats when we get 1-2' of snow... not looking forward to that!
LOL Flood, yea I did LOL I was tired of the dry spell :)~

Actually I noticed the pattern earlier this year. Whats happening is 2 fold. There is now a thermal high over the southeast due to the drought which is keeping the Lows over the Lakes but alowing the cold fronts to extend down south. Second the NAO has been stayin neutral to negative thus allowing for blocking patterns to setup and dig the jetstream southbound. Going to be winter for sure up here. I did miss the mark on my early season forcast though because I didnt think the thermal high would build in the way it did. I figured at least on tropical system would effect that region and break the cycle.
hey Flood. That storm image looks like the Turkish Evil Eye. India is so overpopulated...they are going to have a tough time with this one.
Lake, Calcutta has 14-16 million and an a mean elevation above sea level of 1.5 meters...much like New Orleans, there a re large areas of the city that will flood, not to mention that right next door is Bangladesh with a coutry-wide mean elevation of about 1 meter...it's going to be very wet very soon
Ok kitty's on the move, sky's getting dark. Here comes the first warmer wetter round of this system.
yea Sidr is nasty

CI# /Pressure/ Vmax
6.8 / 904.4mb/134.8kt


Talk about models having a tough call for Northeast

GETS VERY INTERESTING AFTER THIS. SOME MODELS...LED BY THE GFS...
SHOOT A QUICK MOVING CLIPPER TYPE SYSTEM OFF THE NJ COAST BY
SATURDAY NIGHT. THIS LOW THEN DEEPENS AFTER IT PUSHES E OF NEW
ENGLAND SUNDAY NIGHT AND MONDAY WITH HIGH PRESSURE ANCHORED NORTH
OF THE ST. LAWRENCE SEAWAY. THIS COULD GIVE NORTHERN MAINE A SHOT
AT SOME APPRECIABLE SNOW. OTHER MODELS...LED BY THE 00Z ECMWF AND
GGEM...BRING A COLD FRONT THROUGH WITH ANOTHER SHOT OF COLDER AIR
BEHIND IT FOR THE LATTER PART OF THE WEEKEND INTO EARLY NEXT WEEK.
HOWEVER...THE HIGH ELONGATES FROM NE-SW ACROSS NORTHERN NEW
ENGLAND...WHICH PUTS COASTAL AREAS INTO A PERSISTENT NORTHEAST FLOW.
THIS MAY LEAD TO OCEAN EFFECT CLOUDS/SCATTERED PRECIP EARLY NEXT
WEEK...AND MAY SEE SOME MIXED RAIN/SNOW SHOWERS AT NIGHT IF TEMPS
ARE COOL ENOUGH. MAY START TO SEE SOME OF THIS AS LOW LEVEL MOISTURE
INCREASES...MAYBE LATE MONDAY OR TUESDAY.
That cold front in the west is deepening. That's what I got my eye on, that sucker will dump the white stuff on me, Bone you say it'll be here by Fri? I thought Sat. because of the temp forecasts.
NEW BLOG!!!!!
WWIN40 DEMS 140300
IWB 14NOV.2007 MNG

THE VERY SEVERE CYCLONIC STORM SIDR OVER SE-BAY AND ADJ CENTRAL BAY MOVED FURTHER N-WARDS AND NOW LIES OVER E-C AND ADJ W-C AND SE-BAY CENTRED AT 0300 UTC OF TODAY THE 14 NOV 2007 WITHIN HALF A DEG OF LAT.14.5 DEG N/LONG. 89.5 DEG ABOUT 920 KMS SOUTH OF KOLKATA(.) SYSTEM IS LIKELY TO INTENSIFY FURTHER AND MOVE IN A N-LY DIRECTION AND CROSS WEST BENGAL-BANGLADESH COTS NEAR SAGAR ISLAND BY 16 NOV. MORNING(.)

The movement of TC Sidr north into the Bay of Bengal is a potential disaster of immense proportions unfoling before our eyes. So far the news media seems to have taken little notice; I did find these news links:
Cyclone Sidr Aims for the Worst Spot a Hurricane Could Hit
Cyclonic storm spares Orissa, likely to cross Sagar Island

The Bay of Bengal is a very low-lying and densely populated area, consisting of extensive mangrove swamps and many river deltas including those of the large Ganges, Meghna, and Brahmaputra rivers. Its funnel-shape and extensive shallow bathymetry help contribute to the potential for large storm surges. Since we are past new moon the tides at the time of landfall will be past their extremes, but as this tidal chart for Sagar Island shows, tidal variation is will still be close to 3 meters close to the currently predicted point of landfall, so the precise time of landfall and speed of the storm may be a critical issue. Besides being the home of at least 160,000 people, Sagar Island is also the site of one of the most revered temples in the Hindu religion, where "On the 14th of January every year pilgrims come from all over India, quarter million people on the average but sometimes one million or more" (Pilgrimage on the ocean - development of Sagar island, Bay of Bengal). Not unlike many areas in the Mississippi Delta, the Ganges Delta has been an area that has lost much of its natural defenses from storms due to human development and mismanagement. According to a recent study,

"Morphological changes on Sagar Island are occurring at an alarming rate due to both natural and anthropogenic activities. The eastern part of the island is rapidly eroding due to destabilization and growth of tidal flats in the Muriganga estuary and the gradual shifting of water current towards the island. Over the last four years (1996-1999), the rate of coastal erosion has been much higher (11.35 km 2 ) than accretion (2.65 km 2 ), compared with the conditions prior to 1996.[...}(Coastal geomorphological and land%u2010use and land%u2010cover study of Sagar Island, Bay of Bengal (India) using remotely sensed data).

According to the Weather Quality Reporter, the location of Sagar Island Station 42903 is imprecisely reported. A satellite map of Sagar Island and the surrounding region can be found on their site, here.

Hopefully Dr. M will be updating us on this potentially catastrophic situation in his next update.
(Edit -While I was working on this post and before it was even posted, Dr. M did indeed provide an update on this situation with a very informative entry into his blog).