Extreme events of 2011: climate change a major factor in some, but not all

By: Dr. Jeff Masters , 1:54 PM GMT on July 11, 2012

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The science of quantifying how climate change changes the odds of extreme weather events like droughts and floods took a major step forward Tuesday with the publication of NOAA's annual summary of the past year's weather. The 2011 State of the Climate report contains a separate peer-reviewed article published in the July issue of the Bulletin of the American Meteorological Society titled, Explaining Extreme Events of 2011 From a Climate Perspective. In the paper, a group of scientists led by Peter Stott of the Met Office Centre in the United Kingdom looked at how climate change may have changed the odds of occurrence of some of 2011's notable weather extremes. These kinds of attribution studies require huge amounts of computer time and take many months to do, but the scientists plan to start making this a regular part of the annual NOAA State of the Climate report. Some of their findings for 2011:

- Determining the causes of extreme events remains difficult. While scientists cannot trace specific events to climate change with absolute certainty, new and continued research help scientists understand how the probability of extreme events change in response to global warming.

- La Niña-related heat waves, like that experienced in Texas in 2011, are now 20 times more likely to occur during La Niña years today than La Niña years fifty years ago.

- The UK experienced a very warm November 2011 and a very cold December 2010. In analyzing these two very different events, UK scientists uncovered interesting changes in the odds. Cold Decembers are now half as likely to occur now versus fifty years ago, whereas warm Novembers are now 62 times more likely.

- The devastating 2011 floods in Thailand caused an estimated $45 billion in damage, making it the world's most expensive river flooding disaster in history. The study found, however, that the amount of rain that fell in the catchment area was not very unusual, and that other factors such as human-caused changes to the flood plain and the movement of more people into flood-prone areas were more important in causing the disaster. "Climate change cannot be shown to have played any role in this event," the study concluded, but warned that climate models predict an increase in the probability of extreme precipitation events in the future in the region.

- The deadly drought in East Africa, which killed tens of thousands of people in 2011, was made more likely by warming waters in the Indian Ocean and Western Pacific. While the scientists did not specifically tie the warming of these waters to human-caused global warming, they noted that climate models predict continued warming of these waters in the coming decades, and this will likely "contribute to more frequent East African droughts during the spring and summer."


Figure 1. An SH-60F Sea Hawk helicopter assigned to Helicopter Anti-Submarine Squadron (HS) 14, flies around the Bangkok area with members of the humanitarian assessment survey team and the Royal Thai Armed Forces to assess the damage caused by the 2011 floods. Image credit: Petty Officer 1st Class Jennifer Villalovos.

Weather on steroids
One interesting aspect of the paper was the scientists' use of the baseball player-steroids analogy to help explain how climate change can increase the odds of extreme weather: "One analogy of the effects of climate change on extreme weather is with a baseball player (or to choose another sport, a cricketer) who starts taking steroids and afterwards hits on average 20% more home runs (or sixes) in a season than he did before (Meehl 2012). For any one of his home runs (sixes) during the years the player was taking steroids, you would not know for sure whether it was caused by steroids or not. But you might be able to attribute his increased number to the steroids. And given that steroids have resulted in a 20% increased chance that any particular swing of the player’s bat results in a home run (or a six), you would be able to make an attribution statement that, all other things being equal, steroid use had increased the probability of that particular occurrence by 20%. The job of the attribution assessment is to distinguish the effects of anthropogenic climate change or some other external factor (steroids in the sporting analogy) from natural variability (e.g., in the baseball analogy, the player’s natural ability to hit home runs or the configuration of a particular stadium)."



Video 1. National Center for Atmospheric Research scientist Dr. Jerry Meehl explains how climate change's impact on extreme weather is like how steroids affect a baseball player.

Jeff Masters

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Quoting Skyepony:
Blob off the SE coast of FL is looking good. Slight rotation on radar. Land is working it today. MLB WRF still making an invest or depression of it in the east gulf. Another wave should come across the central state fri/sat. WRF looks like it might try to eventually sucks that into East GOM blob making one of those multivortcity messes that never really forms well. The other models aren't picking up on it, even the blob there now other than a midlevel vorticity that is quickly blown out.


TWC says this area is something to watch over the coming days in their Tropical Outlook. This blob looks good on sat and it is even sending rain bands up toward Melbourne which hasn't had much rain at all so far this month so this is great news for the east coast of FL.

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Quoting GeorgiaStormz:


NHC doesnt diagnose frontal lows.

Any rotations shows up on TCFP maps.
it has the highest chance south of the carolinas where nothing is anymore.

but i really dont see anything there


not saying it will or won't just thought it worth noting.
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Quoting GeorgiaStormz:
Floridians, why are you all excited about rain?
Just 2 weeks ago you said you didnt want anymore rain for the rest of the year....
:)
. ask the 5,000 homes around tampa that lost power in the middle of a horrble storm, they might have an answer, lightning like I have never seen before, waves of strikes, unreal
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Quoting Gearsts:
Why is everything and El derecho now?
there is no derecho in Louisiana currently.. my guess to the answer you seek is two-fold
1). the actual recent derecho was a very large, destructive system generating a lot of buzz.
2). folks use the term far too casually for systems that have a bow echo appearance, but meeting the actual criteria for derecho classification is not all that frequent.
still, there are several of them in the CONUS each year.
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Also we have sandy soil and bright hot sun which quickly dries things out. Rain is something we absorb really well and delight in here in Florida. The good thing is, it never usually lasts very long and really helps cool things down.
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Quoting Chicklit:
Georgia, the low on your map and mine is north of this little spinny thing to the south.
NHC isn't mentioning it yet but I'd look for something at 2 p.m. if its still there.
And it shows up on Largo's TF prob map in post #47.


NHC doesnt diagnose frontal lows.

Any rotations shows up on TCFP maps.
it has the highest chance south of the carolinas where nothing is anymore.

but i really dont see anything there
Member Since: February 11, 2012 Posts: 0 Comments: 9726
Quoting GeorgiaStormz:
Floridians, why are you all excited about rain?
Just 2 weeks ago you said you didnt want anymore rain for the rest of the year....
:)


We just love these summer thunderstorms in FL. You know they call us the lightning capital of the US for a reason and some could argue we are the lightning capital of the world. These thunderstorms here produce such a show daily 6 months out of the year that many find it fascinating to watch.
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74. Skyepony (Mod)
Blob off the SE coast of FL is looking good. Slight rotation on radar. Land is working it today. MLB WRF still making an invest or depression of it in the east gulf. Another wave should come across the central state fri/sat. WRF looks like it might try to eventually sucks that into East GOM blob making one of those multivortcity messes that never really forms well. The other models aren't picking up on it, even the blob there now other than a midlevel vorticity that is quickly blown out.
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Georgia, the low on your map and mine is north of this little spinny thing to the south.
NHC isn't mentioning it yet but I'd look for something at 2 p.m. if its still there.
And it shows up on Largo's TF prob map in post #47.
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Quoting Chicklit:

I think it is the bottom of the front.



nope, here you see the low on the front and the front that is nearly stationary and extends across the SE and out to sea:



What you see as the bottom of the front is just where to front is barely moving north or south, it is still the same boundary just barely moving in different directions in certain places

Member Since: February 11, 2012 Posts: 0 Comments: 9726
Floridians, why are you all excited about rain?
Just 2 weeks ago you said you didnt want anymore rain for the rest of the year....
:)
Member Since: February 11, 2012 Posts: 0 Comments: 9726
500 mile wide fire front in Russia. MODIS satellite image today.

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Quoting GeorgiaStormz:


not off the middle of the front, if anything formed it would be on the bottom of the front.
If it formed on the middle it would get pushed along and sheared by the front and would never form.

It is simply a Low pressure forming on the front, a very common occurence.

I think it is the bottom of the front.
Click "fronts" on this map.
Link

The low is moving off to the NE.
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Quoting stormygace:
\?
How many of you really call for Hazmat cleanup when you break a twisty pc lightbulb and release that powdered mercury for those kids to inhale?


you dont need hazmat cleanup.
It really is not bad for you, weve broken quite a few in our house, you clean it up, and its all good.
no evacuation, gas masks, or hazmat necessary.

The effect is negligible
people always overreact to such things
Member Since: February 11, 2012 Posts: 0 Comments: 9726
that blob has been there all morning, they are really getting hammered with rain
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66. 7544
is the fl blob moving nnw or nw seems to be stationary at this hour ? tia
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Quoting oreodogsghost:
We have a drencho in Houston!
..be careful, there will be alot of flooding from this
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Just curious - for the anthropogenic global warming crowd - how many of you have limited your breeding (especially to less than 2 offspring)? How many of you telecommute or videoconference attendence to work or academic/ continuing education conferences (instead pulling Al Gore's jet routine) instead of burning hydrocarbons for that"face time" at conferences (on AGW of all ironies)? How many of you forgo toting the whole overblown family to vacations far from home (especially to places that expend vast amounts of energy to heat/cool or entertain in artificial environments), expending lotsa hydrocarbons, rather than having stay-cations or bicyleable trips with your clutches?
How many of you really call for Hazmat cleanup when you break a twisty pc lightbulb and release that powdered mercury for those kids to inhale? What's your thermostat set at? Do you really have a garden, compost or vermiculture your non-meat kitchen waste? What are you going to do with that Prius when the battery doesn't hold its charge anymore? Just wondering. Big Al et al.certainly have demonstrated some sort of leadership by example, no?

Oh Jeff - congrats on the big sale of Wunderground to The Weather Channel. I suspect we'll be seeing many more scientific explanations like that baseball player on steroids analogy. Thanks for paving the way.
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Quoting oreodogsghost:
We have a drencho in Houston!

good one!
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Quoting Chicklit:


We've seen edges of troughs or fronts split in that area and then spin south into a subtropical or tropical storms before.


not off the middle of the front, if anything formed it would be on the bottom of the front.
If it formed on the middle it would get pushed along and sheared by the front and would never form.

It is simply a Low pressure forming on the front, a very common occurence.


pcola this is to you too ;)
Member Since: February 11, 2012 Posts: 0 Comments: 9726
Quoting GeorgiaStormz:
why dont we mass produce sulfates and aerosols like the ones that come from volcanos and continually emit them while cutting down on carbon.
We could make our goal to reduce insolation to 80% of our pre-greenhouse gas level so as the reverse the effect slowly
Ive seen hydrogen sulfide as a candidate, why not continually produce and release millions of tons of it?

It seems like it would work faster
..the methane seeping out in the artic is a much more potent threat than our carbon..no one is paying attention to that fact, wonder why...maybe they cant get any taxes out of That?
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Quoting LargoFl:
.........................there's going to be some serious flooding in Texas today


To bad Houston is split in the middle!
Member Since: August 18, 2011 Posts: 0 Comments: 598
Quoting GeorgiaStormz:


a cold front?


We've seen edges of troughs or fronts split in that area and then spin south into a subtropical or tropical storms before.
Am sure there are more than a few people on here who could tell you exactly which ones and when!
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We have a drencho in Houston!
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Quoting StormTracker2K:


It just keeps pouring here. Looks like it's going to be like this all day.
yeah it will be my turn later on, locals are saying it will be stronger storms than yesterdays..we will see
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Quoting weatherh98:
We have derecho In central la
Why is everything and El derecho now?
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Quoting LargoFl:


It just keeps pouring here. Looks like it's going to be like this all day.
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...DISCUSSION...

GULF OF MEXICO...
AN UPPER RIDGE COVERS THE W GULF ANCHORED OVER THE DESERT SW/NW
MEXICO EXTENDING AN AXIS ALONG THE N GULF COAST TO THE
ALABAMA/FLORIDA BORDER. A CUTOFF UPPER LOW IS IN THE SE GULF
CENTERED NEAR 23N88W WITH A TROUGH AXIS EXTENDING NW TO CEDAR
KEY FLORIDA AND SW TO THE CENTRAL BAY OF CAMPECHE. A SURFACE
TROUGH EXTENDS OVER THE NE GULF AT 11/0900 UTC TALLAHASSEE
FLORIDA ALONG 27N87W TO 23N88W WITH ISOLATED SHOWERS/
THUNDERSTORMS WITHIN 120 NM ON BOTH SIDES OF THE TROUGH AXIS.
A SECOND SURFACE TROUGH IS INLAND OVER THE W YUCATAN PENINSULA
WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 20N BETWEEN
91W-96W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER THE
SE GULF FROM 24N-26N E OF 83W ACROSS S FLORIDA AND THE FLORIDA
KEYS. THE SURFACE RIDGE IS BEGINNING TO RETREAT ACROSS FLORIDA.
SE SURFACE FLOW COUPLED WITH THE OPPOSING FLOW ALOFT IS
GENERATING SCATTERED TO NUMEROUS SHOWERS AND SCATTERED
THUNDERSTORMS N OF 27N BETWEEN LAKE CHARLES LOUISIANA AND N OF
BROWNSVILLE TEXAS. A WEAK COLD FRONT WILL MOVE INTO THE NW GULF
THU STALLING FROM THE MISSISSIPPI DELTA TO SE TEXAS THU NIGHT
AND THEN MOVE BACK NW OF AREA ON FRI. TROPICAL WAVE OVER THE
WINDWARD PASSAGE WILL ENTER THE STRAITS OF FLORIDA ON THU INTO
THE CENTRAL GULF SAT AND ACROSS THE SW GULF ON SUN.
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why dont we mass produce sulfates and aerosols like the ones that come from volcanos and continually emit them while cutting down on carbon.
We could make our goal to reduce insolation to 80% of our pre-greenhouse gas level so as the reverse the effect slowly
Ive seen hydrogen sulfide as a candidate, why not continually produce and release millions of tons of it?

It seems like it would work faster
Member Since: February 11, 2012 Posts: 0 Comments: 9726
Quoting weatherh98:
We have derecho In central la
whoa thats a bad line of storms there
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Member Since: July 17, 2009 Posts: 71 Comments: 26037
50. 7544
well at least we can now say the blob is heading fooooooooooooor !
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Quoting TropicalAnalystwx13:
We're not going to get anything to form anywhere this month with all these Upper Level Lows moving across the Atlantic.





TUTT
Member Since: June 17, 2011 Posts: 11 Comments: 6482
We have derecho In central la
Member Since: June 17, 2011 Posts: 11 Comments: 6482
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Quoting Chicklit:


Interesting feature off The Carolinas.
LinkEastUSRainbowloop


a cold front?
Member Since: February 11, 2012 Posts: 0 Comments: 9726
Quoting LargoFl:
..................................St.Pete Beach,quiet here right now, nothing going on around here just yet
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Interesting feature off The Carolinas.
LinkEastUSRainbowloop
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SPECIAL WEATHER STATEMENT
LAZ034-035-046-047-MSZ068-111500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
900 AM CDT WED JUL 11 2012

...LINE OF SHOWERS AND ISOLATED STRONG THUNDERSTORMS MOVING EAST
AFFECTING WILKINSON COUNTY...WEST BATON ROUGE PARISH...POINTE COUPEE
PARISH...WEST FELICIANA PARISH...IBERVILLE PARISH...

AT 851 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SHOWERS AND THUNDERSTORMS FROM 20 MILES WEST OF WOODVILLE
MISSISSIPPI TO NEAR KROTZ SPRINGS LOUISIANA...MOVING EAST AT 20 MPH.

THE LINE OF SHOWERS AND STRONG THUNDERSTORMS WILL AFFECT AREAS IN
AND AROUND...LETTSWORTH...LOTTIE...BATCHELOR...MORGANZ A...
LIVONIA...WAKEFIELD...SPILLMAN...NEW ROADS...GROSSE
TETE...ERWINVILLE...BRUSLY...BAYOU SORREL...ADDIS...WOODVILLE...FORT
ADAMS...RAMAH AND MARINGOUIN

THE PRIMARY THREATS FROM THESE STORMS ARE FREQUENT LIGHTNING AND WIND
GUSTS OF 35 TO 40 MPH...WHICH COULD DOWN TREE LIMBS AND BLOW AROUND
UNSECURED SMALL OBJECTS. SEEK SHELTER IN A SAFE HOME OR BUILDING
UNTIL THESE STORMS HAVE PASSED.

THESE STORMS COULD PRODUCE RAINFALL AMOUNTS OF ONE TO TWO INCHES IN A
SHORT PERIOD OF TIME...RESULTING IN PONDING OF WATER AROUND LOW LYING
ROADWAYS. REMEMBER...DO NOT DRIVE YOUR VEHICLE INTO WATER COVERED
ROADWAYS. THE DEPTH MAY BE TOO GREAT TO ALLOW A SAFE CROSSING.

$$
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Quoting TropicalAnalystwx13:
We're not going to get anything to form anywhere this month with all these Upper Level Lows moving across the Atlantic.





let them talk...
its easier that way :)
Member Since: February 11, 2012 Posts: 0 Comments: 9726
UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 11 JUL 2012 Time : 133000 UTC
Lat : 14:23:41 N Lon : 117:01:48 W


CI# /Pressure/ Vmax
6.1 / 947.1mb/117.4kt


Final T# Adj T# Raw T#
6.0 6.2 6.2

Estimated radius of max. wind based on IR : 15 km

Center Temp : -13.1C Cloud Region Temp : -71.2C

Scene Type : EYE

Positioning Method : RING/SPIRAL COMBINATION

Ocean Basin : EAST PACIFIC
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : ON
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 80km
- Environmental MSLP : 1010mb

Satellite Viewing Angle : 26.7 degrees

************************************************* ***

Member Since: July 6, 2010 Posts: 113 Comments: 31917
From 8 a.m. NHC Tropical Weather Discussion:
TROPICAL WAVE OVER THE W ATLC WILL MOVE THROUGH THE STRAITS OF FLORIDA THU NIGHT AND EARLY FRI.
A SECOND TROPICAL WAVE WILL REACH THE CENTRAL ATLC ON
FRI NIGHT AND INTO THE E CARIBBEAN SAT.


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Quoting hydrus:
I am just checkin some pics..Not feeling well today.

\
Hang in there..maybe the day will get better for you..
I know blogging takes my mind off my "issues" :)
Member Since: August 13, 2009 Posts: 13 Comments: 6819
We're not going to get anything to form anywhere this month with all these Upper Level Lows moving across the Atlantic.



Member Since: July 6, 2010 Posts: 113 Comments: 31917
.........................there's going to be some serious flooding in Texas today
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Quoting islander101010:
stormtops.day.of.glory...i.thought.no.way


i keep hearing about storm top.
what did he do with katrina?
Member Since: February 11, 2012 Posts: 0 Comments: 9726
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Quoting pcola57:


'Morning Hydrus..
Is that image from the "K" storm in 05 or a current image?
(I know I'm too lazy to look it up this am.. :) )
I am just checkin some pics..Not feeling well today.
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Quoting pcola57:


'Morning Hydrus..
Is that image from the "K" storm in 05 or a current image?
Good morning 57..It is the K-storm.
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Quoting hydrus:
Moving over Miami W-SW too.
stormtops.day.of.glory...i.thought.no.way
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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