How oil might affect a hurricane
There's no major changes to the forecast for the Gulf of Mexico oil spill. As I discussed in yesterday's post, on Sunday, the winds will begin increasing and shifting to the southeast. The latest run of the GFS model shows that this will be a week-long period of southeast winds, with wind speeds at times reaching 20 - 25 knots. These winds will threaten to bring oil to a large portion of the Louisiana coast, including regions of the central Louisiana coast west of the mouth of the Mississippi River. The Mississippi and Alabama coasts will also be at risk next week, but the risk to the Florida Panhandle is lower. Yesterday's post also has the long-range outlook for oil to get into the Loop Current and spread to the Florida Keys and beyond.
What will oil in the Gulf of Mexico do to a hurricane?
With hurricane season fast approaching and the oil spill in the Gulf of Mexico likely to still be around once hurricane season starts in June, we need to ask, how will oil affect any hurricanes that might traverse over the spill? And how might a hurricane's wind and storm surge affect the spill? Let's consider the first of those questions today.
From the time of the ancient Greeks to the days of the wooden ships and iron men, mariners dumped barrels of oil onto raging seas to calm them during critical moments of violent storms (Wyckoff, 1886.) Oil does indeed calm wind-driven waves, thanks to the reduction in surface tension of the water that oil causes. Ripples with a wavelength shorter than 17 mm are affected by surface tension, and these ripples then cause a feedback that reduces the height of larger waves with longer wavelengths (Scott, 1986.) The reduction of surface tension also impacts the flow of air above the water, and reduces the amount of sea spray thrown into the air, both of which could affect the wind speed. Oil also damps waves by forming a thick, viscous film at the top of the water that resists water motion (Scott, 1999.) Oil also helps calm raging seas by switching off of the wind energy input needed by the wave to break. This occurs because the surface film of oil prevents the generation of ripples on the exposed crests of the waves, and this smoother surface makes the wind less able to grab onto the wave and force it to break.
So, what would happen to a hurricane that encounters a large region of oily waters? A 2005 paper by Barenblatt et al. theorize that spray droplets hurled into the air by a hurricane's violent winds form a layer intermediate between air and sea made up of a cloud of droplets that can be viewed as a "third fluid". The large droplets in the air suppress turbulence in this "third fluid", decrease the frictional drag over the ocean surface, and accelerate the winds. According to this theory of turbulence, oil dumped on the surface of the ocean would reduce the formation of wind-whipped spray droplets, potentially calming the winds. The authors propose spraying oil on the surface of the ocean to reduce the winds of a hurricane. However, the turbulence theory championed by Barenblatt et al. has been challenged by other scientists. In a 2005 interview with Newscientist magazine, turbulence expect Julian Hunt at University College London, UK, remarks, "I am very doubtful about this approach." Hunt studies turbulence both theoretically and in the laboratory, and believes that the high wind speeds in a hurricane are not caused by sea spray. In an article he wrote for the Journal of Fluid Dynamics, Hunt suggests that variations in the turbulence between different regions of the hurricane cause sharp jumps in wind speed, which are responsible for the hurricane's strongest winds.
Oil reduces evaporation
Hurricanes are sustained by the heat liberated when water vapor that has evaporated from warm ocean waters condenses into rain. If one can reduce the amount of water evaporating from the ocean, a decrease in the hurricane's strength will result. Oil on the surface of the ocean will act to limit evaporation, and could potentially decrease the strength of a hurricane. However, if the oil is mixed away from the surface by the strong winds of a hurricane, the oil will have a very limited ability to reduce evaporation. According to a 2005 article in Popular Science magazine, Dr. Kerry Emanuel of MIT performed some tests in 2002 to see if oil on the surface of water could significantly reduce evaporation into a hurricane. He found that the slick quickly dissipated under high wind conditions that generated rough seas.
Figure 1. A comparison of the size of 2008's Hurricane Gustav with the size of the Gulf oil spill. The spill is only about 60 miles in diameter, while a hurricane like Gustav is typically 400+ miles in diameter.
Conclusion
A tropical cyclone in its formative stage--as either a tropical depression or a tropical storm with 40 mph winds--might be adversely affected if it encountered the Gulf of Mexico oil slick, due to the reduction of evaporation into the storm. However, a full-fledged hurricane would mix the oil into the ocean to such a degree that the storm would probably not see any significant reduction in evaporation. It remains unknown how the reduction of sea spray by oil might affect a hurricane. If the oil slick expands to a much larger size, there might be a significant reduction in strength of the hurricane, if theory of how a reduction of sea spray will decrease a hurricane's winds is correct. However, the oil slick is currently Delaware-sized, while a hurricane tends to be Texas-sized, and I doubt that the oil slick at its current size is large enough to have a significant impact on a hurricane's intensity. The slick is about 60 miles across, and it would take a hurricane about four hours to traverse the spill at a typical hurricane forward speed of 15 mph. Furthermore, the slick is within 50 miles land, and interactions with land will dominate the behavior of a hurricane that gets that close to the coast. Unfortunately, there is a decent chance that we'll get a real-world opportunity to see what will happen. June tropical storms tend to form in the Gulf of Mexico, and we've been averaging one June storm every two years since 1995. This year, the odds of a June Gulf of Mexico storm are probably a little lower than usual, shear from our lingering El Niño may bring wind shear levels a bit above average. I expect there is a 20% chance that we'll see a June tropical storm in the Gulf of Mexico that would interact with the oil spill.
References
Barenblatt, G.I, A.J. Chorin, and V.M. Prostokishin, 2005, A note concerning the Lighthill sandwich model of tropical cyclones, PNAS August 9, 2005 vol. 102 no. 32 11148-11150 doi: 10.1073/pnas.0505209102.
Hunt, J.C.R, and I. Eames, 2006, Mechanics of inhomogeneous turbulence and interfacial layers,, Journal of Fluid Dynamics, vol. 554, pp. 499519 doi:10.1017/S002211200600944X.
Scott, J.C., 1986, "The Effect of Organic Films on Water Surface Motions," in Oceanic Whitecaps, edited by E. C. Monohan and G. Mac Niocaill, D. Reidel Publishing Company.
Scott, J.C., 1999, Ocean Surface Slicks - "Pollution, Productivity, Climate and Life-saving", IEEE Proceedings of the International Geoscience and Remote Sensing Symp. IGARSS99, Hamburg, Germany, 28 June-2 July 1999, vol. 3, pp 1463-1468, 1999.
Wyckoff, A.B., 1886, The Use of Oil in Storms at Sea, American Philosophical Society, April 2, 1886.
http://www.archive.org/stream/proceedingsofamep23 amer/proceedingsofamep23amer_djvu.txt
First tropical wave of the season leaves the coast of Africa
Yesterday, the National Hurricane Center noted the first tropical wave of the year coming off the coast of Africa in their Tropical Weather Discussion. The first half of May is the typical time when the first tropical wave comes off the coast of Africa. The wave is currently positioned in the far eastern Atlantic near 5N 45W, and I don't expect it to develop, since it is too close to the Equator to leverage the Earth's spin to gain the rotation needed. The wave has quickly been joined by two new ones today, located at 15W and 36W off the African coast. Tropical waves serve as the seed that form most Atlantic and Eastern Pacific hurricanes.
Portlight delivers major aid shipment to Haiti
Portlight continues to focus its energy and funds on the situation in Haiti, where the rainy season is fast approaching the needs for shelter, medical supplies, food and water remain urgent. Their latest effort was a shipment of several thousand pounds of Durable Medical Equipment and 30,000 pounds of rice that arrived this week via the schooner Halie and Mathew.
Portlight.org is also preparing to respond the the Gulf Coast oil spill by deploying one of more mobile kitchens to feed the hundreds of volunteers likely to flood the coast when the oil finally comes ashore. Please visit the Portlight.org web site or the Portlight blog to learn more and to donate to Portlight's efforts in Haiti and the Gulf Coast.
Figure 2. Relief supplies from the schooner Halie and Mathew sitting at the Portlight Haiti warehouse, ready for distribution.
Next Post
I'm on my way to Tucson today for the American Meteorological Society's 29th Conference on Hurricanes and Tropical Meteorology, which will be held in Tucson next week. My next post will probably be on Monday night, when I plan to discuss the record SSTs observed last month in the tropical Atlantic. I'm excited to be catching up on and blogging about all the latest advancements in hurricane research!
Jeff Masters
Reader Comments
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 — Blog Index
So how was Friday? Just so we know what to expect...LOL
Although SST's look high is TCHP high too? It seems like it's still rather low but then again I'm not an expert on the subject.
Just like any other day except its FRIDAY!!!!!!!!!
But a turn from its Westward movement to WestNorthWestward could lead the wave
to a position near that of a storm on 27June1933.
And as the WU aphorism goes:
When the Doctor's away, the first Storm will play.
Dr. Ed Overton at LSU was of the opinion that it will actually disperse the oil. He seems to be a credible source but ya never know...
But it is only May 7th. Conditions are not conducive for a system to develop from a Cape Verde wave in May - and usually in June.
Good morning. Barb, check out the "E" Volcano, it's erupting up to near 30,000 ft:
Link
Subject: C5d) Why don't we try to destroy tropical cyclones by adding a water absorbing substance ?
Contributed by Hugh Willoughby (FIU)
"Dyn-O-Gel" is a special powder (produced by Dyn-O-Mat) that absorbs large amounts of moisture and then becomes a gooey gel. It has been proposed to drop large amounts of the substance into the clouds of a hurricane to dissipate some of the clouds thus helping to weaken or destroy the hurricane.
At HRD we tried the one possible way that "Dyn-O-Gel" could weaken a hurricane in the MM5 numerical model. We saw an effect but it was small (~1 m/s). The argument was that the glop would make raindrops lumpy (i. e., non-aerodynamic) they would fall slower and increase condensate loading, thus weakening the eyewall updraft. If, by contrast, one increases the fall speed of the hydrometeors, the storm strengthens (again by only ~1 m/s). In the numerical experiments "decrease" meant reduce the fall velocity to half the real value, and "increase" meant double the real value. The foregoing effect is larger than anything one could hope to produce in the real atmosphere.
The observation that the experiment that "Dyn-O-Gel" conducted actually "dissipated" clouds is problematic. Did they watch any unmodified clouds ? Isolated Florida cumuli have short lifetimes, and these are just the ones an experimenter would logically pick.
Accepting for the sake of argument that they actually did have an effect, the descriptions seem more consistent with an increase in hydrometeor fall speed and accelerated collision coalescence, which the numerical model results argue would strengthen the hurricane, but not much. If this speculation proves to be correct, "Dyn-O-Gel" might be useful for rainmaking during a dry spell, unlike glaciogenic seeding which (in the tropics at least) tends to make rainy days even more rainy--if it does anything at all.
One of the biggest problems is, however, that it would take a LOT of the stuff to even hope to have an impact. 2 cm of rain falling over 1 square kilometer of surface deposits 20,000 metric tons of water. At the 2000-to-one ratio that the "Dyn-O-Gel" folks advertise, each square km would require 10 tons of goop. If we take the eye to be 20 km in diameter surrounded by a 20km thick eyewall, that's 3,769.91 square kilometers, requiring 37,699.1 tons of "Dyn-O-Gel". A C-5A heavy-lift transport airplane can carry a 100 ton payload. So that treating the eyewall would require 377 sorties. A typical average reflectivity in the eyewall is about 40 dB(Z), which works out to 1.3 cm/hr rain rate. Thus to keep the eyewall doped up, you'd need to deliver this much "Dyn-O-Gel" every hour-and-a-half or so. If you crank the reflectivity up to 43 dB(Z) you need to do it every hour. (If the eyewall is only 10 km thick, you can get by with 157 sorties every hour-and-a-half at the lower reflectivity.)
Think of the Cyclones as the driving force of the Planets Heat Pump.
Good evening, Bordo. Saw you and Dan on eruptions blog the last days ... Really impressing plume today and more trouble for some parts of the air traffic to come
"E" is blowing off plenty of both ash and steam this morning, up and over 30,000 ft. Yesterday, ash was up to about 42,000 ft and villages in Iceland up to 40 miles away were getting blanketed with ash.
She's really blowing her top again.
Ok which wise guy pushed the wrong button on her.
Hey, Aussie. A lot of *wrong buttons" to be seen over there
Map with earthquakes at Eijaf
or that Sham Wow dude.....
just like the NYSE guy that made a typo
It wasn't me :o). Luckily, for the moment the ash plume is only affecting Irish airspace and a portion of the Trans-Atlantic Corridor as one flies eastward towards Europe. The ash plume is about 600-1000 miles wide and 700+ miles long.
There is an area of High pressure forcing the ash SE then S ward. IF the upper level winds push this towards Europe, besides the Greece debt problem and a temporary 989 point drop in the Dow yesterday (boo-boo's on the trading floor, partially caused by "computer error), European airspace will be a disaster!
maybe Beano would help?
Nordic Volcanological Center
Just another *wrong button", pressed by someone, lol.
Could you imagine some sticking 40 million sham-wow's down the "E" vent? That would be one heckuva mess!
I'm blaming the NYSE guy
Link
About 320 million Americans were FREAKING out. Could you image what another "Great Recession" would be like, after this last nightmare??
Freaking out?
Not his phella,..
Numbers never hurt anyone on a screen.
Seems the nightmare yesterday was a mirage..,
Floor traders can go the way of the Dinosaurs,and we would all be better off.
Gulf of Mexico Oil Spill Response
Gulf of Mexico-Transocean Drilling Incident/www.deepwaterhorizonresponse.com
DATE: May 07, 2010 10:15:19 CST
Media Advisory: Unified Command to hold press briefing in Robert, La.
* Report oiled shoreline or request volunteer information:
(866)-448-5816
* Submit alternative response technology, services or products:
(281) 366-5511
* Submit your vessel as a vessel of opportunity skimming system:
(281) 366-5511
* Submit a claim for damages:
(800) 440-0858
* Report oiled wildlife:
(866) 557-1401
Deepwater Horizon Incident
Joint Information Center
Phone: (985) 902-5231
(985) 902-5240
Who: U.S. Coast Guard Rear Adm. Mary Landry, BP Chief Operating Officer Doug Suttles.
What: An update to the status of the lowering of the oil containment dome and the ongoing response efforts to continue to attack and contain the pollution on and below the surface surrounding the Deepwater Horizon incident.
Where: Shell Robert Training and Conference Center, 23260 Shell Lane in Robert, La., 70455-1928. A Unified Area Command joint information center representative will be at the gate at 1:30 p.m., to escort media.
When: 2 p.m. CDT. The call-in number for press unable to attend: (877) 918-5750. International callers use (312) 470-7364 Password – RESPONSE (73776673).
Live broadcast may be available on the Digital Video Information Distribution System (DVIDS) hub, which can be accessed at www.dvidshub.net. To see the live broadcast or download video of the conference, media must register with DVIDS no later than 1:45 p.m. This can be done on the DVIDS Web site or by calling (678) 421-6612.
RSVP: Media interested in attending should arrive no earlier than 12:30 p.m.
Click'latestposts' if it's not updated
netstat.exe description
cmd.exe description
"E" is having an ash/steam party this afternoon in Iceland.
East of 120W is still warm.
Charlie Christ will be at my building within the hour and a couple of Senators.
Thanx for the Warning...
Christ has a new First Name?
And I always thought it was Jesus.
Recent earthquake activity under "E"
That's one big ash cloud. Looks like we may see European air traffic closed again.
High speed rail lookin better n better.
"Regulators are reviewing a plunge that briefly wiped out more than $1 trillion in market value yesterday"
That's not play money :(
Ya win some,ya Lose some.
Try Palmolive group,Blue Liquid dawn iz a rolling.
Thanks, I did a scan with Malwarebytes' Anti-Malware and it picked up 6 issues. pc is running fine now
Link
Viewing: 51 - 101
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 — Blog Index