Solar impacts on hurricanes
I'm in Tucson for the American Meteorological Society's 29th Conference on Hurricanes and Tropical Meteorology. This is the premier scientific conference on hurricanes, and is held only once every two years, so pretty much all of the world's greatest hurricane experts are here. One of the more intriguing posters presented at Tuesday's poster session was titled, Evidence linking solar variability with USA hurricanes, by Robert Hodges and Jim Elsner of Florida State University. They showed that the probability of three or more hurricanes hitting the U.S. during a hurricane season with warmer than average sea surface temperatures increases dramatically during minima in the 11-year sunspot cycle. The odds increase from 20% to 40% for years when the sunspot activity is in the lower 25% of the sunspot cycle, compared to years in the upper 25% of the cycle. Near the peak of the sunspot cycle, the odds of at least one hurricane hitting the U.S. are just 25%, but at solar minimum, the odds increase sharply to 64%. The authors studied the period 1851 - 2008, and controlled for other variables such as changes in sea surface temperature and El Niño. Such a large impact of the sun on hurricanes might seem surprising, given that the change in solar energy at all light wavelengths is only about 0.1%. This relatively small change causes just a 0.1°C change in Earth's mean surface temperature between the peak of the 11-year sunspot cycle (high solar activity) and the minimum of the sunspot cycle (where we are now.) However, variation in radiation between extrema of the solar cycle can be 10% or more in portions of the UV range (Elsner et al., 2008.) The strong change in UV light causes globally averaged temperature swings in the lower stratosphere of 0.4°C between the minimum and maximum of the sunspot cycle--four times as great as the difference measured at Earth's surface (Lean, 2009). This sensitivity of the stratosphere to UV light is due to the fact the ozone layer is located in the stratosphere. Ozone absorbs a large amount of UV light, causing the stratosphere to heat up when solar activity is high. The authors speculate that a warmer stratosphere then heats up the upper troposphere, making the atmosphere more stable. An unstable atmosphere--with hot temperatures at the surface and cold conditions in the upper troposphere--are conducive for stronger hurricanes. Thus, we would expect to see reductions in hurricanes during the peak of the sunspot cycle.
Previous research
The findings presented at this week's conference build upon earlier work published by Elsner et al. (2008) and Elsner et al. (2010). The first of these studies found that for every 100 extra sunspots in September, the temperature of the atmosphere at 16 km altitude over the Caribbean and Gulf of Mexico increased by about 0.5°C, and the number of hurricanes in this region was reduced by 26%. Interestingly, a reduction of hurricanes over the eastern Atlantic off the coast of Africa was not observed during solar maxima, which the authors attributed to the fact that hurricanes in this region are limited by sea surface temperature, not instability. Solar maximum brings a small increase in sea surface temperature to the globe, aiding hurricane development in regions where sea surface temperature is the limiting factor. The second of these studies (Elsner et al., 2010) computed that for a Category 2 hurricane affecting the U.S. during the most active 30% range of the solar cycle, the resultant heating of the upper troposphere would cause a 19% decrease in the stability, lowering the hurricane's winds by 10% (10 mph.) Stronger hurricanes would be affected even more, with a potential wind speed reduction of 23 mph for the most powerful hurricanes. The 27-day rotation period of the sun causes a change in UV light even larger than the change observed during the 11-year sunspot cycle, so perhaps we should be monitoring the phase of the sun's rotation to look for more favorable periods for hurricane formation.
Commentary
Considering that this year we are at the deepest solar minimum in more than a century, this research gives us yet another reason to expect a severe Atlantic hurricane season this year. My next post, which may not be until Monday, I'll discuss the sea surface temperatures in the Atlantic hurricane main development region, which set an all-time record last month for the warmest monthly anomaly for the 100+ years we have records. Also, El Niño now appears to be over, as sea surface temperatures in the Eastern Pacific have crossed the threshold into neutral territory.
References
Elsner, J. B., and T. H. Jagger, 2008, United States and Caribbean tropical cyclone activity related to the solar cycle, Geophys. Res. Lett., 35, L18705, doi:10.1029/2008GL034431.
Elsner, J. B., T. H. Jagger, and R. E. Hodges, 2010, Daily tropical cyclone intensity response to solar ultraviolet radiation, Geophys. Res. Lett., 37, L09701, doi:10.1029/2010GL043091.
Lean, J.L., 2009, Cycles and trends in solar irradiance and climate", Wiley Interdisciplinary Reviews: Climate Change, Volume 1, Issue 1, Pages 111-122 Published Online: 22 Dec 2009
Jeff Masters
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Real funny coming from people who worship their model "projections" which are supposed to be so infallable that not believing in them is a sin. Oh well....lol.
The global models didn't pick up on the El Nino and warm temps last year until it was already in progress. The same has happened with this La Nina as the CFS just a month ago finally came out of lala land and picked up on the very obvious trend. That model is an embarrassment. Now that they have all caught on more or less, we're seeing the cooling trend this winter, and in my opinion 2011 will see a crash in temps similar to after the 1998 El Nino. We will likely dip below the zero line on global temp anomalies sometime next year. This winter will probably be brutal overall globally. What happens after that remains to be seen.
Work on the first relief well, which began on Sunday May 2, continues. It is expected to take some three months to complete. The drilling rig that will drill the second relief well is currently en route to the site, expected to arrive by Friday.
Link
The thing with the existing oil-flow from the Gulf Well, is that right now there are kinks and blockages (perhaps even a semi-closed BOP) restricting the flow. (a good thing)
If it was free-flowing, the entire gulf would be filled with oil already almost. There is about 10,000 PSI of pressure behind the leak. Look at the leak in Pat's video a little earlier. That's a relative dribble. A free flowing well would have vast amounts of oil and gas pelting out of it.
One of the obvious concerns is that, as the oil leaks through cracks in the pipe, the cracks may be being continuously sand blasted into bigger and bigger holes as sand under high pressure erroded the cracks.
A slight nudge could rupture or break the riser pipe from the BOP too, causing free-flow. Thats why there is so much care being taken with the placement of the top hat. IMO.
Also, I think that the idea of the other well, to intercept the leaking one, is to be able to pump heavy mud (Baroid etc) into the hole and abandon the well. Others can be drilled into this formation to produce the oil later.
The MJO is currently organizing over the Indian Ocean and Maritime Continent, and will likely be moving into our area of the world between May 25th and June 10th. During that time we may stir up some mischief in the Caribbean, but we will have to see if we can get a tropical wave or disturbance in there during that time to take advantage of it.
The positive pressure tests on the well were good,the negative pressure test were NOT good.
Im well aware,no pun intended, of the circumstances on the Trans Ocean Rig pre blowout.
Its well documented.
I spent 2.6 years on Hercules 21 for Chevron in the mid-90's
Agreed.
Sorry for applying the stereotype, but rarely is anyone in here on the AGW side of things who isn't exactly the same as everyone else. You are not as bad as some others here though.
I see nothing close to organizing there....Sorry!
Looks like I gonna hav to water my plants agin!
...well....I( think that train has long ago left the station...
* Personnel were quickly deployed and approximately 13,000 are currently responding to protect the shoreline and wildlife.
* More than 510 vessels are responding on site, including skimmers, tugs, barges, and recovery vessels to assist in containment and cleanup efforts—in addition to dozens of aircraft, remotely operated vehicles, and multiple mobile offshore drilling units.
* Approximately 1.5 million feet of boom (regular and sorbent) have been deployed to contain the spill—and approximately 1.5 million feet are available.
* Approximately 4 million gallons of an oil-water mix have been recovered.
* Approximately 436,000 gallons of dispersant have been deployed. More than 120,000 gallons are available.
Skimmers are out in full force, have been for some time now.
www.deepwaterhorizonresponse.com
i are ride of all ignernce an i are fully loded of c0ommen since
Just found out the tri-state is under a tornado watch. Better keep an eye on the weather.
Tornado Warning for North Central Arkansas
Thats all you have to say? Thank Goodness!
LOL
You are giving PressLord too many ideas.....that is beautiful!
LMAO
They way overpaid and under sourced.
No... it's proof of Global Cooling :P!
For ACTUAL PROOF THAT GLOBAL COOLING WILL COME, look at this image of a Climate Model for the Winter of 2010-2011.
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