Causes of the Russian heat wave and Pakistani floods
The Great Russian Heat Wave of 2010 is one of the most intense, widespread, and long-lasting heat waves in world history. Only the European heat wave of 2003, which killed 35,000 - 50,000 people, and the incredible North American heat wave of July 1936, which set all-time extreme highest temperature records in fifteen U.S. states, can compare. All of these heat waves were caused by a highly unusual kink in the jet stream that remained locked in place for over a month. The jet stream is an upper-level river of air, between the altitudes of about 30,000 - 40,000 feet (10,000 - 12,000 meters). In July over Europe and Asia, the jet stream has two branches: a strong southern "subtropical" jet that blows across southern Europe, and a weaker "polar" jet that blows across northern Europe. The polar jet stream carries along the extratropical cyclones (lows) that bring the mid-latitudes most of their precipitation. The polar jet stream also acts as the boundary between cold, Arctic air, and warm tropical air. If the polar jet stream shifts to the north of its usual location, areas just to its south will be much hotter and drier than normal. In July 2010, a remarkably strong polar jet stream developed over northern Europe. This jet curved far to the north of Moscow, then plunged southwards towards Pakistan. This allowed hot air to surge northwards over most of European Russia, and prevented rain-bearing low pressure systems from traveling over the region. These rain-bearing low pressure systems passed far to the north of European Russia, then dove unusually far to the south, into northern Pakistan. The heavy rains from these lows combined with Pakistan's usual summer monsoon rains to trigger Pakistan's most devastating floods in history.
Figure 1. Winds of the jet stream at an altitude of 300 millibars (roughly 30,000 feet high). Left: Average July winds from the period 1968 - 1996 show that a two-branch jet stream typically occurs over Europe and Asia--a northern "polar" jet stream, and a more southerly "subtropical" jet stream. Right: the jet stream pattern in July 2010 was highly unusual, with a very strong polar jet looping far to the north of Russia, then diving southwards towards Pakistan. Image credit: NOAA/ESRL.
What caused this unusual jet stream pattern?
The unusual jet stream pattern that led to the 2010 Russian heat wave and Pakistani floods began during the last week of June, and remained locked in place all of July and for the first half of August. Long-lived "blocking" episodes like this are usually caused by unusual sea surface temperature patterns, according to recent research done using climate models. For example, Feudale and Shukla (2010) found that during the summer of 2003, exceptionally high sea surface temperatures of 4°C (7°F) above average over the Mediterranean Sea, combined with unusually warm SSTs in the northern portion of the North Atlantic Ocean near the Arctic, combined to shift the jet stream to the north over Western Europe and create the heat wave of 2003. I expect that the current SST pattern over the ocean regions surrounding Europe played a key role in shifting the jet stream to create the heat wave of 2010. Note that the SST anomaly pattern is quite different this year compared to 2003, which may be why this year's heat wave hit Eastern Europe, and the 2003 heat wave hit Western Europe. Human-caused climate change also may have played a role; using climate models, Stott et al. (2004) found it very likely (>90% chance) that human-caused climate change has at least doubled the risk of severe heat waves like the great 2003 European heat wave.
Figure 2. A comparison of the departure of sea surface temperature (SST) from average just prior the the start of the great European heat waves of 2003 and 2010. Temperatures in the Mediterranean Sea were up to 4°C above average in 2003, which has been implicated as a major cause of the Western European heat wave of 2003. Image credit: NOAA/NESDIS.
References
Feudale, L., and J. Shukla (2010), "Influence of sea surface temperature on the European heat wave of 2003 summer. Part I: an observational study", Climate Dynamics DOI: 10.1007/s00382-010-0788-0
Stott, P.A., Stone, D.A., and M.R. Allen (2004), "Human contribution to the European heatwave of 2003", Nature 432, 610-614 (2 December 2004) | doi:10.1038/nature03089. (Here is a free version of the paper, presented at a conference.)
The World Meteorological Organization (WMO) has posted an analysis of the recent extreme weather events, concluding, "the sequence of current events matches IPCC projections of more frequent and more intense extreme weather events due to global warming."
See also my posts, The Great Russian Heat Wave of 2010: 102°F in Moscow and, Over 15,000 likely dead in Russian heat wave; Asian monsoon floods kill hundreds more.
Moscow sees real relief from the Great Russian Heat Wave of 2010
For the first time in more than a month, temperatures at Moscow's Domodedovo airport failed to exceed 30°C (86°F) today. Clouds and thunderstorms blew into the city this morning, keeping the high temperature down to just 29°C (84°F). This breaks a string of 35 straight days when the temperature reached 30°C. At Moscow's official observing site, the Moscow Observatory, this string was 30 days. Moscow's average high temperature for August 13 is 20°C (68°F), so today's temperatures were still well above normal. However, today's cool-down marks the beginning of the end for Russia's great heat wave. The latest forecast for Moscow calls for high temperatures below 30°C for the coming week, and Moscow may not exceed that threshold for the remainder of summer. Long range forecasts from the ECMWF and GFS models continue to suggest that a series of troughs of low pressure will attack the ridge of high pressure anchored over Russia, bringing cooler temperatures just 5°C (8°F) above average to Russia late next week. By ten days from now, the ECMWF model shows a strong trough of low pressure over Moscow, and a end to the Great Russian Heat Wave of 2010. Moscow still has to concern itself with smoke from the wildfires burning southeast of the city; winds are expected to shift early next week and bring the smoke towards the city again. However, the cooler weather should aid fire-fighting efforts, so the smoke problems should not be as bad as last week's nightmare.
Figure 2. Image from NASA's Aqua satellite of smoke from wildfires burning to the southeast of Moscow yesterday, August 12, 2010. Northerly winds were keeping the smoke from blowing over the city. Image credit: NASA.
The tropics are quiet
The remnants of Tropical Depression Five continue to bring heavy rain to portions of Southeast Louisiana today. Up to five inches of rain has fallen in regions near New Orleans. The GFS model predicts that the remains of TD 5 could move off the coast of Mississippi by the middle of next week and regenerate, but none of the other models is making this forecast. Both the GFS and ECMWF models are predicting that a tropical storm will develop off the coast of Africa by next Friday, August 20.
Donations urgently needed in Pakistan
The devastation wrought by the worst flooding in Pakistan's history requires a huge response by the international community. Wunderblogger Dr. Ricky Rood, author of our Climate Change Blog, has a friend working in Pakistan who underscored the desperate situation there:
This is the worst natural disaster in the history of Pakistan in terms of number of people and area affected. Although not as many people have been killed as in the 2005 earthquake, we have already nearly 900,000 displaced persons thus far just in Khyber Pakhtunkhwa. Crops are destroyed; shops, hotels, and other business have simply been swept away in Swat, which had just this year been cleared of Taliban and was on the way to recovery; and districts closer to Peshawar and parts of Peshawar district are still, or perhaps again after yesterday/today, under water. After the immediate emergency response, it will be years of rebuilding to replace what has been lost and to start to develop again. I know you have the power to control the weather, so if you cold give us a week or two without more rain at least we could keep the helicopters flying and give people a chance to go to their homes, recover what might still be there, set up tents if we can get enough to them, and start to clean up."
She gave the following recommendations for charities that do work in the flood-ravaged zone, and are effective at getting aid to those who need it the most:
Doctors Without Borders
The International Red Cross
MERLIN medical relief charity
The mobile giving service mGive allows one to text the word "SWAT" to 50555. The text will result in a $10 donation to the UN Refugee Agency (UNHCR) Pakistan Flood Relief Effort.
She mentioned that it is better to send money to the organizations doing the relief work than to try to organize shipments of goods.
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 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 — Blog Index
Without the reservations of the hate mail I have recently recieved, I would, If living by any beach-side real-e-state, do as you advise, STAY VIGILANTE!! I fear my original intent was somehow overlooked, as all I meant was the 2010 Hurricane season is far from over. September is a ferocious month historically, And one would be wise to comprehend many a assessment on how it just may play out.
Origins of the Tropical Cyclones
Of the tropical cyclones that affected the designated area in Louisiana and Texas, 38 originated in the Gulf of Mexico, 16 in the Carribean Sea, 15 in the Atlantic, and 2 in the East Pacific Ocean. Since 1886 the earliest storm to arrive in the region was on May 30th in 1959 (minimal tropical storm Arlene), and the latest storm affected the area on October 28th in 1985 (hurricane Juan)
xxtd5
La Nina's have been known to feature an East Coast trough.
Really? I would have thought it was the opposite. Most La Nina seasons that I've seen have featured an anomalous southward extension of the subtropical ridge, forcing the majority of storms into the Caribbean and Gulf of Mexico.
JULY
AUGUST
SEPTEMBER
OCTOBER
That's what I thought too.
Only four cyclones of the 71 which have affected the Lake Charles area formed in the Atlantic north of the 20th parallel, two of which formed north of the 30th parallel. One of the tropical cyclones that entered Louisiana initially made landfall in Georgia and moved westward through the southeastern United States just inland from the Gulf Coast, never fully emerging into the Gulf of Mexico. This fact means that even though a brewing storm may seem far away off the Carolina coast, there remains a remote possibility that it may yet affect the northwestern Gulf Coast. This shows why it is important to take a good look and pay close attention to systems most anywhere in the Atlantic basin; they may eventually become a real threat to the Louisiana and Texas shoreline
cmc gfs nam ECMWF,UKMET shows xxxtd5 -Possible tropical development
Hey man.. Just keep on slinging those honest assessment's, and I'll keep on pluggin em, ya heard??
cv storms & further south
I'm thinking, more of 07. Felix, Dean, what you may have. North ATL is currently a graveyard, as seen with Colin, 93L ETC. We seem situated in a 07 pattern, high sst, tchp, 26 iso and ect, however, steering moving W - east
2007 was my guess months ago. But back then we had a negative NAO for months that I didn't think would change. Well it went positive so it's yet to be seen how this one will play out.
PREFERENCE: GFS/ECMWF COMPROMISE
WITH THE MID LVL REFLECTION THE GFS/NAM OFFER FAIRLY SIMILAR
TRACKS THOUGH THE GFS IS SLIGHTLY STRONGER THAN THE NAM FOR MOST
OF THE FCST. THE SFC LOW THAT DEVELOPS ALONG THE GULF COAST IS
ALSO DEEPER IN THE GFS... WITH THAT MODEL BECOMING SLIGHTLY SLOWER
THAN THE NAM WITH THE WWD MOTION BY MON-TUE. THE 00Z GEFS MEAN IS
SIMILAR TO AND EVENTUALLY A TAD WWD OF THE GFS SFC LOW BUT THE
ECMWF/UKMET/CANADIAN GLBL ARE ALL EWD OF THE GFS TO VARYING
DEGREES. THE CMC IS THE MOST EXTREME ERN SOLN AND THE UKMET IS
SOMEWHAT EXTREME AS WELL AROUND SUN BEFORE RETURNING CLOSER TO
CONSENSUS BY LATER IN THE FCST. THE ECMWF IS FAIRLY CONSISTENT
AND LEAST EXTREME OF THE ERN SOLNS. CONFIDENCE IN SPECIFICS OF
THIS SYSTEM IS LOW DUE TO LACK OF WELL DEFINED STEERING ALOFT AND
QUESTIONS OVER HOW MUCH OF THE CONCENTRATED QPF SEEN IN THE MODELS
MAY BE REAL VERSUS FEEDBACK THAT MAY BE ADVERSELY IMPACTING SYSTEM
EVOLUTION. PREFER A COMPROMISE OF THE GFS AND WEAKER/EWD ECMWF TO
YIELD A REASONABLE INTERMEDIATE SOLN RELATIVE TO THE FULL ARRAY OF
GUIDANCE. NOTE THAT QPF PREFERENCES MAY DIFFER FROM MASS FIELD
PREFERENCES.
HPC
FORECAST DISCUSSION
You asked me to email you so I could get the links to all the cool satellites and models, but i don't know your email. Or did you want my email?
look at xxxtd5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
340 AM EDT SAT AUG 14 2010
MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA
AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.
GULF OF MEXICO...
THE REMNANT OF TROPICAL DEPRESSION FIVE CONTINUES AS AN
ELONGATED AREA OF LOW PRES EXTENDING FROM ERN LOUISIANA E-NE
THROUGH CENTRAL MISSISSIPPI AND INTO CENTRAL ALABAMA. LOWEST
PRES EARLY THIS MORNING WERE NEAR BIRMINGHAM AL. THIS FEATURE IS
CUT OFF FROM THE MAIN FLOW AND WILL LINGER ACROSS THIS GENERAL
AREA THROUGH SUN BEFORE HIGH PRES RIDGING FROM THE W ATLC PUSHES
THIS ELONGATED LOW PRES SW AND ALONG THE N GULF COASTS OF AL AND
MS MON THROUGH TUE. UPPER LEVEL RIDGING OVER THIS SYSTEM COULD
ALLOW IT TO REINTENSIFY AS IS SHIFTS OVER THE WARM GULF
WATERS...AND THUS EXACTLY HOW FAR OUT OVER WATER THIS LOW MOVES
MAY BE CRITICAL. WEAK HIGH PRES RIDGE E TO W ALONG 27N ACROSS
THE BASIN IS HELPING TO MAINTAIN 15 KT SW-W FLOW ACROSS THE FAR
N GULF E OF 90W...WHERE SEAS HAVE FINALLY LOWERED TO 3-4 FT.
CURRENTLY...LIGHT ANTICYCLONIC FLOW PREVAILS ACROSS THE
REMAINDER OF THE BASIN SAVE FOR 15 KT FLOW OFF THE N YUCATAN AND
THE FAR SW GULF...BOTH TYPICAL FOR THESE AREAS.
LIGHT WINDS AND TRANQUIL CONDITIONS WILL CONTINUE THROUGH
SUN...WITH WINDS ALONG THE NE GULF COASTS DIMINISHING TO 10-15
KT AS THE INLAND LOW WEAKENS FURTHER. HOWEVER AS THE LOW
APPROACHES THE COASTLINE SUN NIGHT INTO MON SW TO S WINDS AT 15
KT AND POSSIBLY 15-20 KT SHOULD BE EXPECTED N OF 28N AND E OF
90W. SLY RETURN FLOW IS THEN FORECAST TO OPEN UP ACROSS THE
BASIN AND HELP TO GUIDE WHATEVER EVOLVES FROM THIS LOW PRES AREA
INLAND ACROSS SW LOUISIANA AND/OR FAR ERN TEXAS. CONFIDENCE
REMAINS LOW STILL IN ANY SIGNIFICANT DEVELOPMENT OF THIS LOW AND
THUS HAVE REMAINED ON THE MODERATE SIDE OF WINDS...INCREASING
WINDS TO 15-20 KT IN THE SE QUAD OF THIS LOW AS IT TRACKS ACROSS
THE N CENTRAL GULF TUE AND WED.
while every one is keeping a close eye on the disturbance over africa which is earmarked to develop into a significant system in 8- 10 days time, i am watching an area of disturbed weather in the itcz near 7N 30W. there is a mid level circulation and very low wind shear . the shear according to the wind shear maps from cimss is forecast to remain low for the next few days. there is good convergence and divergence in the area, the only hindrance to this disturbance is the low latitude. if it could gain some latitude it will be something to watch the next few days
I heard that too....Daw-than,AL. Can't Accuweather edit that and insert him pronouncing it the correct way? The camera shot of him is from a distance anyway.
Bastardi doesn't know how to pronounce Dothan?
Jeff is the first storm the one near 10w?
Looks that way.
It may miss it's Exit to Ike's house, if it dont take a right turn today...
typical 2010
On this blog...probably.
Looks like a true Cape Verde system by this time next week. All of the models show it.
My prediction...
(1)There will be tons of "west"-casting going on.
(2)A few will say a track to Florida even though it's 4,000 miles away.
(3)Some will say..."aren't you forgetting the islands? They're first and foremost".
(4)Those that like to beat their chests will say...this is what I've been saying would happen. Even though their previous forecasts were wrong.
(5)Some will say....where are the downcasters and season-is-a-bust crowd at now?
.............................................
I'm gonna write down this post number and refer back to it in a few days, to a week or so.
***better yet...I'll bookmark this page...lol***
Viewing: 1251 - 1301
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 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 — Blog Index