Are atmospheric flow patterns favorable for summer extreme weather increasing?

By: Dr. Jeff Masters , 2:45 PM GMT on March 11, 2013

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In 2010, Russia baked through its most intense heat wave in recorded history, one that killed over 55,000 people. At the same time, intense rains deluged Pakistan, bringing that nation its worst natural disaster in its history. The following year, it was the United States' turn for extreme heat, as the nation sweltered through its third hottest summer on record, and Oklahoma suffered the hottest month any U.S. state has ever recorded. The U.S. summer of 2012 was even more extreme. Only the Dust Bowl summer of 1936 was hotter, and drought conditions were the most extensive since the 1930s. All of these events--and many more unusually extreme summer months in recent decades--had a common feature, said scientists at the Potsdam Institute for Climate Impact Research (PIK) in Germany, in a research paper published in March 2013 in Proceedings of the National Academy of Sciences. According to the authors, "each time one of these extremes struck, a strong wave train had developed in the atmosphere, circling the globe in mid-latitudes. These so-called planetary waves are well-known and a normal part of atmospheric flow. What is not normal is that the usually moving waves ground to a halt and were greatly amplified during the extreme events. Looking into the physics behind this, we found it is due to a resonance phenomenon. Under special conditions, the atmosphere can start to resonate like a bell. The wind patterns form a regular wave train, with six, seven or eight peaks and troughs going once around the globe". Using a complex theoretical mathematical description of the atmosphere and 32 years of historical weather data, the scientists showed that human-caused global warming might be responsible for this resonance phenomenon, which became twice as common during 2001 - 2012 compared to the previous 22 years.


Figure 1. Drought-damaged corn in a field near Nickerson, Nebraska, Aug. 16, 2012. The great U.S. drought of 2012 was the most extensive U.S. drought since the 1930s Dust Bowl. Damage from the 2012 drought is at least $35 billion, and probably much higher. The associated heat wave killed 123 people, and brought the U.S. its second hottest summer on record. (AP Photo/Nati Harnik)


Figure 2. Business was slow at the Lake Conroe, Texas jet ski rental in 2011, thanks to the great Texas drought and heat wave of 2011. Texas endured its driest 1-year period on record in 2011, and had the hottest summer ever recorded by a U.S. state. July 2011 in Oklahoma was the hottest month any U.S. state has ever recorded, and the contiguous U.S. had its third hottest summer on record. The total direct losses to crops, livestock and timber from the drought, heat wave, and record fires of the summer of 2011 are estimated at $12 billion, with a death toll of 95. Image credit: wunderphotographer BEENE.


Figure 3. Tourists wear protective face masks as they walk along the Red Square in Moscow, Russia on Aug. 6, 2010. Moscow was shrouded by a dense smog that grounded flights at international airports and seeped into homes and offices, due to wildfires worsened by the city's most intense heat wave in its history. The heat wave and fires during the summer of 2010 killed over 55,000 people in Russia and decimated the Russian wheat crop, causing global food prices to spike. (AP Photo/Mikhail Metzel)

Two fundamental atmospheric flow patterns may be resonating more often due to global warming
Earth's atmosphere has two fundamental patterns. One is a series of wave-like troughs and ridges in the jet stream called planetary (or Rossby) waves, which march west-to-east at about 15 - 25 mph around the globe. The other pattern behaves more like a standing wave, with no forward motion, and is created by the unequal heating of the equatorial regions compared to the poles, modulated by the position of the continents and oceans. A number of papers have been published showing that these two patterns can interact and resonate in a way that amplifies the standing wave pattern, causing the planetary waves to freeze in their tracks for weeks, resulting in an extended period of extreme heat or flooding, depending upon where the high-amplitude part of the wave lies. But what the Potsdam Institute scientists found is that because human-caused global warming is causing the Arctic to heat up more than twice as rapidly as the rest of the planet, the two patterns are interacting more frequently during the summer. During the most recent eleven years, 2002 - 2012, there were eight Julys and Augusts that showed this unusually extreme resonance pattern (this includes the U.S. heat wave of July - August 2012.) The two previous eleven year periods, 1991 - 2001 and 1980 - 1990, had just four extreme months apiece. Global warming could certainly cause this observed increase in the resonance phenomenon, but the researchers cautioned, "The suggested physical process increases the probability of weather extremes, but additional factors certainly play a role as well, including natural variability. Also, the 32-year period studied in the project provides a good indication of the mechanism involved, yet is too short for definitive conclusions. So there's no smoking gun on the table yet--but quite telling fingerprints all over the place."



Figure 4. The northward wind speed (negative values, blue on the map, indicate southward flow) at an altitude of 300 mb in the mid-latitudes of the Northern Hemisphere during July 2011 and July 1980. July of 2011 featured an unusually intense and long-lasting heat wave in the U.S., and the normally weak and irregular waves (like observed during the relatively normal July of 1980) were replaced by a strong and regular wave pattern. Image credit: Vladimir Petoukhov.

Commentary
The new Potsdam Institute paper gives us a mathematical description of exactly how global warming may be triggering observed fundamental changes in large-scale atmospheric flow patterns, resulting in the observed increase in unusually intense and long-lasting periods of extreme weather over the past eleven years. The paper also adds important theoretical support to the research published in 2012 by Dr. Jennifer Francis of Rutgers University, which found that the amplitude of Earth's planetary waves had increased by over 100 miles (161 km) in summer over the past decade in the Northern Hemisphere. Dr. Francis theorized that this change was connected to increased heating of the Arctic relative to the rest of the Earth, due to the observed decline in late spring Northern Hemisphere snow cover. Humans tend to think linearly--one plus one equals two. However, the atmosphere is fundamentally non-linear. What may seem to be modest changes in Earth's climate can trigger unexpected resonances that will amplify into extreme changes--cases where one plus one equals four, or eight, or sixteen. In some cases, when you rock the boat too far, it won't simply roll a bit more, it will reach a tipping point where it suddenly capsizes. Similarly, human-caused global warming is capable of pushing the climate past a tipping point where we enter a new climate regime, one far more disruptive than what we are used to.

Julys and Augusts since 1980 when quasiresonant extreme conditions were observed
The Potsdam Institute's research lists sixteen July and August periods since 1980 that have had extreme atmospheric flow patterns due to quasiresonance. These months featured severe regional heat waves and destructive floods in the Northern Hemisphere midlatitudes, detailed below. Half of these months occurred in the most recent 11-year period, 2002 - 2012. During most of these extreme months, there was not a moderate or strong La Niña or El Niño event contributing to the extremes. Summers when a La Niña or El Niño event was present are listed in parentheses, based on the Oceanic Niño Index (ONI).

July and early August 2012: Catastrophic floods in China and Japan, as well as record-breaking temperatures during heat waves in the United States and southern Europe (weak summer El Niño)

July 2011: Record heat wave in the United States, resulting in the fourth warmest July on record nationally and the driest conditions in the southern United States ever (weak summer La Niña)

July/August 2010: Russian heat wave and the Pakistan flood, with the strongest and most persistent extreme weather conditions and the highest death tolls from heat waves and floods ever for these two regions (strong summer La Niña)

July 2006: Temperatures higher than 100°F for only the second time in Britain’s history and much of Europe experiencing a serious heat wave (weak summer El Niño)

August 2004: Much of northern Europe hit by very low winter-like temperatures and sporadic snowfalls (moderate to strong summer El Niño)

August 2003: European summer 2003 heat wave, causing a highly persistent drought in western Europe (weak summer El Niño)

August 2002: Catastrophic Elbe and Danube floods (strong summer El Niño)

July 2000: Destructive floods in northern Italy and the Tisza basin and a simultaneous heat wave in the southern United States, smashing all-time high-temperature records by that time at many sites (strong summer La Niña)

July/August 1997: Disastrous Great European Flood, which caused several deaths in central Europe, and the destroying floods in Pakistan and western United States (strong summer El Niño)

July 1994: Very strong heat wave in southern Europe, with a national temperature record of 47.2°C set in Spain (weak summer El Niño)

July 1993: Unprecedented great flood in the United States that reigned over the country from April (weak summer El Niño)

July 1989: Unusually intense and unprecedented widespread drought in the United States (weak summer La Niña)

August 1987: Severe drought in the southeastern United States (strong summer El Niño)

August 1984: Continuation of the severe heat of summer 1983, with serious drought in the United States (weak summer La Niña)

July and August 1983: Very dry conditions, severe heat, and substandard crop growth (5–35% below normal) in the Midwest United States (weak summer El Niño)

Links
Petoukhov, V., Rahmstorf, S., Petri, S., Schellnhuber, H. J. (2013), "Quasi-resonant amplification of planetary waves and recent Northern Hemisphere weather extremes" Proceedings of the National Academy of Sciences, (Early Edition) [doi:10.1073/pnas.1222000110]. No subscription required, but understanding this article requires a graduate-level understanding of the mathematical theory of atmospheric dynamics. Try reading instead this easy-to-read description of the paper by the authors, published at http://theconversation.edu.au.

Press release issued in March 2013 by the Potsdam Institute for Climate Impact Research (PIK), "Weather extremes provoked by trapping of giant waves in the atmosphere."

In this 40-minute lecture presented in 2013 at the University of Arkansas, Dr. Jennifer Francis of Rutgers University explains the linkage between warming in the Arctic due to human-caused global warming and an observed shift in Northern Hemisphere jet stream patterns.

Linking Weird Weather to Rapid Warming of the Arctic, a March 2012 article by Dr. Jennifer Francis in the Yale Environment 360.

Francis, J.A., and S.J.Vavrus, 2012, "Evidence linking Arctic amplification to extreme weather in mid-latitudes", GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L06801, doi:10.1029/2012GL051000, 2012

Jeff Masters

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Quoting Gearsts:
What implication does the arabian sea SST have on the atlantic for hurricane season?


It has a very strong positive correlation with ENSO, but I'm not sure what else. It may affect the Indian monsoon circulation, which may affect African easterly waves, but I have not researched it much.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Zulu or GMT or UTC....

If you live at longitude 0 degrees, or along the prime meridian, you don't have to worry about it...it's the same as your local time.

The places are, British Isles, Iceland, Portugal and al western African countries, as will as some Islands in the South Atlantic...

however...
Hours are added if you live to the right or subtracted if you live to the left, the further away the more hours it is...

look at the bottom pic... btw NYC EDT time is 11:12 PM or 03:12 GMT, Z or UTC
Member Since: April 23, 2011 Posts: 104 Comments: 14871
711. txjac
Quoting aspectre:
695 gulfbreeze: Now if we could get China & India to do these things that would make a big difference!!

They'd use about 8times as much fossil fuel as they currently do.


I'm curious as to why you suspect that?
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Quoting Levi32:


I've had UTC/local time conversion completely memorized since I was 9 years old lol. Unfortunately I learned the conversions for during daylight savings time, since that is summer time when I am looking at meteorological products the most, so outside of DST I have to subtract an hour from local, or add an hour to UTC.

I don't mind too much though. I'd rather have the system down during hurricane season than at any other time of the year. Now once I move away from Alaska for graduate school, those conversions won't be fun. I won't be able to stay up for the 0z ECMWF either :(
What implication does the arabian sea SST have on the atlantic for hurricane season?
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695 gulfbreeze: Now if we could get China & India to do these things that would make a big difference!!

They'd use about 8times as much fossil fuel as they currently do.
And there'd be a heck of a lot less recycling going on.
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someone asked me a good question... at any time you can contribute to the poll, not necessarily now..
Member Since: April 23, 2011 Posts: 104 Comments: 14871
Quoting ozelloslim:
I've been following this blog for years and still can't figure what 18z and 24z etc. mean. Can someone help?


They are model times in zulu... GMT
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Sweet Dreams everyone, Should have bailed an hour ago.
Sleep Well - Stay Safe - Hang Loose
Member Since: February 29, 2012 Posts: 0 Comments: 5685
Quoting PedleyCA:


Thanks for taking the time to do that. Now we don't have to remember where we put the scrap of paper that our prediction is scribbled on.


cool thing right...? I have been working on that, thanks for participating...

The purpose of it is to compare our numbers with the other buddies here as well as those of TWC (if they ever give any out), the NHC outlook and at the end of the season to see who was the closest one to the actual results...

We all can argue or agree about it...lol
Member Since: April 23, 2011 Posts: 104 Comments: 14871
Quoting trHUrrIXC5MMX:
I'll have the chart updated tomorrow morning... 12 people listed, some more please!
see post 690 for reference

Thanks!


Thanks for taking the time to do that. Now we don't have to remember where we put the scrap of paper that our prediction is scribbled on.
Member Since: February 29, 2012 Posts: 0 Comments: 5685
Quoting washingtonian115:
I just wish we had the same technology like we do now to track weather back then.If we did it could've proven my theory.


I recently read about this early storm. Although it was April and not March. Would've been interesting to know what was going on in 1554. Lol. It made the Texas hurricane history study where they refer to it as a "spring gale." Another site calls it an early hurricane but also alludes to another storm?

April 1554
: Fifteen of the twenty ships of the New Spain Flota,
with around 300 passengers en route from Vera Cruz to Havana, and loaded with silver and gold along the Lower Texas coast, were demolished during a springtime gale. Three of the heaviest vessels sunk immediately. The other 17 were either scattered across the Gulf of Mexico, grounded, or had capsized just off Padre Island near Devil’s Elbow...three of which were the San Estevan,
Santa Maria de Yciar, and Espiritu Santo Andres. Only300 of the 2000 aboard ship made it to shore alive. But to the misfortune of the Spaniards, they had horrible relations with the local tribe of Native Americans, known as the Karankawa. As they struggled to go south into Mexico, they had to fight them off along the way. Only two of the original 2000 ever lived to tell the tale of their misfortune. Their story prompted salvage vessels to visit the site on July 22nd(Chipman).


A rare Mexican Silver Splash from the 1554 Fleet with a Charles I Quinto.

Treasure found on the wreck of the San Andreas

Four treasure-laden Spanish ships left Vera Cruz for Havana in late April of 1554. When an early season hurricane caught the Admiral Curzo's Flota on April 28th as it entered the Gulf of Mexico, three of the four were driven northwest and wrecked on the Texas coast off Padre Island. One ship, the SAN ANDREAS, though badly damaged, managed to steer a sufficiently northerly course to outrun the hurricane, and eventually turn east for Havana. A rescue squadron under Capt Farfan found the sinking San Andreas north of Havana about a week later and off-loaded her treasure, just as second major storm struck and drove the rescue ships east of Cuba. There, on the shoals that line the coast of what is now known as the Dominican Republic, Capt Farfan's ships wrecked and were lost with the treasure of the San Andreas. More than 500 years would pass before the San Andreas' treasure would see sunlight.

In 2006 a UK-based salvage group was following the suspected track of Farfan's ships and found a 1550's Spanish wreck. They were soon able to confirm its identify because its treasure, coins and bullions, was identical to that found on the Padre Islands wrecks.
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Arctic





Averaged over the 34 years of data coverage, the thickness cycle has peaked in July and reached its minimum in December. Note also that average thickness has decreased over time in all 12 months of the year, the decrease has been much greater during summer and fall months. It has also been most severe quite recently, since 2010. All this has changed the shape and the timing of the annual cycle of thickness. We can see this even more plainly if we compare the average annual cycle for times prior to 2010, to that after 2010:



Averaged over the last three years, the annual thickness cycle has peaked in May and bottomed out in November, shifting its timing by about 2 months. It has also changed its shape. Prior to 2010, the cycle showed a slower rise to maximum and faster drop to minimum, but recently the rise and fall have been at about the same rate so the cycle is more symmetrical about its peak (and is more "sinusoidal").

It's also worth noting that the annual maximum thickness is now about equal to the pre-2010 average annual minimum. The decline in sea ice thickness has combined with the decline in sea ice area to bring about the amazing decline of Arctic sea ice volume.


http://tamino.wordpress.com/2013/03/13/arctic-sea -ice-loss-part-2/
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I'll have the chart updated tomorrow morning... 14 listed now, let's have some more!
see post 690 for reference

Thanks!
Member Since: April 23, 2011 Posts: 104 Comments: 14871
Evening all.... a quick checkin before I head to bed...

We are still experiencing swells from the latest winter storm to come offshore of the CONUS... in particular mailboat sailings have been hampered due to the large swells, but coastal erosion along the eastern islands is also a big concern.

Dunno if anybody posted it, but the swells have also allegedly led to a drowning death here over the weekend.

Additionally, two men of a four-man fishing party have gone missing after boat allegedly capsized this weekend.
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The water temp for Buoy # 13010 is 85.1 F is that normal for this time of the Year?
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Quoting ncstorm:


I have to disagree..I'm going to even use one of the greatest scientists to prove my point in "do as I say"...

When Louis Pasteur who I can say is not Jim invented the process of Pasteurization, did he continue to drink the sour milk that wasnt pasteurized..no he led by example and dranked his own discovery which in turn led to others to adopt the milk we know of today..my point is Louis, Jim, You or I cant put ideas out there for others to commit to if one is not even following them..
In my long experience dealing with climate change, I've found one of the most common denialist tactics is to repeatedly ask, "If you believe the planet is warming, what are you doing about it?". Now, I--and others--have answered that question dozens, perhaps hundreds, of times. I myself have gone into great detail on numerous occasions with details about my lifestyle, my carbon footprint, my own conservation efforts, and so on. And every time I've done so--literally every time--the immediate denialist response has been, "You know, if you really thought climate change was happening, you'd do more." So it wasn't too long before I realized that the question was almost always being asked as a distraction, and very seldom was it asked in earnest. And since I figured that out, I've responded to it with decreasing frequency.

The thing is, if a Michael Mann or a Kevin Trenberth or a Grant Foster or a James Hansen or a Jeff Masters or a Bill McKibben does something that adds to climate change--takes a ride in a jumbo jet, say, or forgets to turn off the light when leaving the house one morning, or sets the office thermostat to 72 instead of 76 one July afternoon--that does nothing to throw the science of climate change into doubt. Nothing. There are many who will jump up and down, shout "Gotcha!!!", and claim that it does, but that doesn't make it so. So repeatedly asking a supporter of climate change theory to explain what they do to combat that change is nothing but a disingenuous--and, let's face it, very unoriginal--ploy to get them to admit to doing something that creates CO2. And for that reason, I--and many others--refuse to waste any further time answering it. We've simply got far more important things to do...
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Quoting 1900hurricane:
I've actually recently changed my phone's time to GMT so I don't have to convert the timestamps on metorological products all the time. However, the drawback is that I have to convert the time for everything else. :P


I've had UTC/local time conversion completely memorized since I was 9 years old lol. Unfortunately I learned the conversions for during daylight savings time, since that is summer time when I am looking at meteorological products the most, so outside of DST I have to subtract an hour from local, or add an hour to UTC.

I don't mind too much though. I'd rather have the system down during hurricane season than at any other time of the year. Now once I move away from Alaska for graduate school, those conversions won't be fun. I won't be able to stay up for the 0z ECMWF either :(
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Quoting trHUrrIXC5MMX:
Score card a little expanded....Still looking for anyone else who would like to join it..
9 people already!.... give it a try...!
Just tell me that you think the outcome of this season is, anyone's opinion counts!

Or go to my blog and give me your numbers...
If you want to make changes let me know as well.
Thanks to those who have already! :)



click on image for larger view.

heres mine 16-8-4
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Quoting Some1Has2BtheRookie:


I agree with you that one should be willing to practice what they preach. You have no idea of what I do on a personal basis and your asking me what I do by means of a blog sight is bit pointless, do you not agree? I could tell that I ride a bicycle everywhere I go, but I do not.

Here is what I "preach":

1. Consume less.

2. Plan trips for the shortest route and combine as many errands as possible into one trip.

3. Recycle all that I can.

4. Repair what is repairable instead of discarding.

5. Donate what is still unusable but I no longer need or want.

6. Adjust your thermostat.

7. Keep your tires properly inflated.

8. Keep your vehicle(s) properly tuned.

9. Drive within the speed limit.

10. Replace your car with a more mileage efficient car when it your car is due to be replaced.

11. Replace incandescent light bulbs with CFL or LED bulbs.

12. Wash clothes in the coldest water possible.

13. Wash a full load of clothes at a time without over loading the washer.

14. Dry clothes no longer to get them dry.

15. Do not completely dry clothes that will be hung in a closet.

What do I actually practice? ALL of the above.

What do I plan to further do to lessen my carbon footprint? I am always looking for ways to further reduce my carbon footprint.

I find it very interesting that you that lower your carbon footprint even though you do not seem to believe there are reasons to do so in order to mitigate the CO2 emissions. Perhaps you have discovered what I have? When you do these things it saves you a lot of money! Should this be incentive to do so, then this is incentive enough.
Now if we could get China & India to do these things that would make a big difference!!
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I've actually recently changed my phone's time to GMT so I don't have to convert the timestamps on metorological products all the time. However, the drawback is that I have to convert the time for everything else. :P
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Greenwich Mean Time – GMT
Greenwich Mean Time (GMT) was adopted as the world’s time standard at the Washington Meridian Conference in 1884. This conference also established Universal Time, from which the international 24-hour time-zone system grew. This is why all time zones refer back to GMT on the prime meridian. The prime meridian at Greenwich, in the United Kingdom, has served as the reference line for GMT since the late 19th century.

The prime meridian was defined by the position of the large “Transit Circle” telescope in the Observatory’s Meridian Building in 1884. The cross-hairs in the Transit Circle’s eyepiece precisely defined longitude 0° for the world. The Earth’s crust is moving very slightly all the time so the prime meridian’s exact position is now moving very slightly too. However, the original reference for the world’s prime meridian is still the Airy Transit Circle in the Royal Observatory in the United Kingdom.

GMT was at first calculated by the 24-hour clock starting at noon. However, since 1925, the day of GMT starts at midnight. GMT was later renamed to Universal Time, or UT. It is also known as UT0. It becomes UT1 when it is corrected for the irregular movements of the terrestrial poles, also known as the Chandler wobble. The Earth’s poles do not spin perfectly in a straight line.

More Developments with Time Systems
Following UT1, the concept of “UT2” was developed to correct certain seasonal variations for better time accuracy. Mechanical clocks are more regular than the sun so the atomic clock is more accurate than the Earth. The concept of Atomic Time was established with the development of mechanical clocks.

The most accurate clocks use an atomic transition in a caesium vapor, which defines a very accurate frequency. This frequency is then divided down to give seconds and minutes. Many atomic clocks are used to define a local time standard time service. There are many separate time services throughout the world and a combined mean version of their time measurement is used as International Atomic Time (TAI). TAI is the International Atomic Time scale, a statistical timescale based on a large number of atomic clocks. However, this takes no notice of the Earth’s rotation as measured by UT1 so another standard for civil time, known as Coordinated Universal Time (UTC), is used.

The Development of UTC
UTC differs from TAI by an integral number of seconds. The addition or subtraction of leap seconds to TAI produces UTC. In other words, a leap second, as measured by an atomic clock, is added to or subtracted from (although subtractions are rare) UTC to make it agree with astronomical time to within 0.9 second. The world's timing centers agreed to keep their real-time timescales closely synchronized (“coordinated”) with UTC. Hence, all these atomic timescales are called Coordinated Universal Time (UTC). UTC relates to solar motion. A constant day of exactly 24 hours is used for civil time keeping purposes.

UTC is often called GMT although the term is used on occasions for UT1. UTC is also the time broadcast since 1972 by radio stations across the world and is popularly referred to as GMT. UTC is also the time system used in aviation and is informally known as Zulu Time to avoid confusion about time zones and daylight saving time. timeanddate.com provides a more detailed explanation about UTC.

Other Time Systems
Astronomers use other measures of time, such as Terrestrial Dynamical Time (TDT), which is 32.184 seconds ahead of TAI. TDT, also known as Terrestrial Time (TT), with a unit of duration 86400 SI seconds on the geoid, is the independent argument of apparent geocentric ephemerides. Therefore:
TDT = TAI + 32.184 seconds.

TDT is used for calculating planetary positions in relation to the Earth’s center. Delta T is the difference between Earth’s rotational time (UT1) and dynamical time (TDT). TDT has been used since 1984. Prior to this, astronomers used a time measure known as Ephemeris Time (ET). Before atomic clocks, Ephemeris Time (ET) was the closest available approximation to a uniform time for planetary motion calculations.

Other time systems include:

■Barycentric Dynamical Time (TDB), the independent argument of ephemerides and dynamical theories that are referred to the solar system barycenter. TDB varies from TT only by periodic variations.
■Barycentric Coordinate Time (TCB), which is a coordinate time having its spatial origin at the solar system barycenter. TCB differs from TDB in rate.
■Sidereal Time, with unit of duration the period of the Earth's rotation with respect to a point nearly fixed with respect to the stars, is the hour angle of the vernal equinox.
■Geocentric Coordinate Time (TCG), a coordinate time having its spatial origin at the center of mass of the Earth.
Note: timeanddate.com wishes to acknowledge some of the information in this article is courtesy of the UK’s National Maritime Museum and the United States Naval Observatory. It is also important to note that this article does not mention every time system but simply provides an overview of time systems.



from time and date.com
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Quoting txjac:


You're crazy Wash! That's why I like you! LOL ...
I just wish we had the same technology like we do now to track weather back then.If we did it could've proven my theory.
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Txjac we're in central time, so there is a six hour difference for standard time and 5 hour difference for daylight savings.
Member Since: May 18, 2006 Posts: 10 Comments: 5953
Score card a little expanded....Still looking for anyone else who would like to join it..
9 people already!.... give it a try...!
Just tell me that you think the outcome of this season is, anyone's opinion counts!

Or go to my blog and give me your numbers...
If you want to make changes let me know as well.
Thanks to those who have already! :)



click on image for larger view.
Member Since: April 23, 2011 Posts: 104 Comments: 14871
689. wxmod
Here's a satellite photo taken today off the coast of California. Is this a new art form? Notice the top circle is about 60 miles in diameter. MODIS


Member Since: October 4, 2011 Posts: 0 Comments: 1738
Quoting ozelloslim:
I've been following this blog for years and still can't figure what 18z and 24z etc. mean. Can someone help?

Z is Zulu time, aka GMT (Greenwich Mean Time). It is just another way of telling time and it is on a 24hr incriminate. Right now it is 02:08z or 2:08 GMT. Hopefully that helps.
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Quoting bappit:
Greenwich Mean Time is also called Zulu time. I think it is military terminology. That's what the "z" stands for.
Quoting txjac:


Does that mean that 18z is 6:00 pm and 24Z midnight?
Quoting ozelloslim:
I've been following this blog for years and still can't figure what 18z and 24z etc. mean. Can someone help?

00z is 8pm EDT, 06z is 2am EDT, 12z is 8am EDT, and 18z is 2pm EDT.
Member Since: July 6, 2010 Posts: 113 Comments: 31462
686. txjac
Quoting bappit:
Greenwich Mean Time is also called Zulu time. I think it is military terminology. That's what the "z" stands for.


Does that mean that 18z is 6:00 pm and 24Z midnight?
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Greenwich Mean Time is also called Zulu time. I think it is military terminology. That's what the "z" stands for.
Member Since: May 18, 2006 Posts: 10 Comments: 5953
I've been following this blog for years and still can't figure what 18z and 24z etc. mean. Can someone help?
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683. txjac
Quoting washingtonian115:
Lol at the models trying to develop a sub-tropical system.
It is my belief and still is to this day the the beginnings of the 1993 super storm that formed in the gulf was at one point sub-tropical.Call me crazy all you want.


You're crazy Wash! That's why I like you! LOL ...
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Lol at the models trying to develop a sub-tropical system.
It is my belief and still is to this day the the beginnings of the 1993 super storm that formed in the gulf was at one point sub-tropical.Call me crazy all you want.
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681. wxmod
Quoting aspectre:
503 wxmod: This planet will look like Venus when we are done.

Not Venus... but it's possible to get quite a bit closer to a Venusian-style greenhouse-runaway than anyone would have thought even a year ago
Traditionally, Earth had been placed in the middle of the HabitableZone around the Sun, with Venus being a little too close to the Sun to provide a long-term habitable atmosphere (ie one that can hold liquid water on the surface for over a billion years).
The most recent planetary atmospheric models show that Venus is by far too close to the Sun to have ever supported conditions that are favorable to the development of life, with the Earth being very close to the inner edge of habitability.


The models are based on observation from the Earth in its present condition. I don't think there are any limits to what can happen or how fast it can happen. What I see in satellite photos is global atmospheric change. Who knows where it will go. One tipping point might quickly lead to another previously unimagined.
Member Since: October 4, 2011 Posts: 0 Comments: 1738
Quoting allancalderini:
You can add me if you want 16 or 17 tropical storms 8 or 10 hurricanes and 3 to 5 majors.


Sure, I'll put in anyone who wants to be added.

sorry for the spelling issue
Member Since: April 23, 2011 Posts: 104 Comments: 14871
Rain is over...lots of run off
Member Since: April 23, 2011 Posts: 104 Comments: 14871
678. etxwx
Quoting ncstorm:


I have to disagree..I'm going to even use one of the greatest scientists to prove my point in "do as I say"...

When Louis Pasteur who I can say is not Jim invented the process of Pasteurization, did he continue to drink the sour milk that wasnt pasteurized..no he led by example and dranked his own discovery which in turn led to others to adopt the milk we know of today..my point is Louis, Jim, You or I cant put ideas out there for others to commit to if one is not even following them..


Or perhaps people may be reluctant to post information about their personal lives on an open internet forum. Lack of specifics about what they are doing or how they live their lives should not necessarily be construed as not leading by example or not practicing what they preach. To me it's just good sense to be circumspect about posting personal information on the internet.
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79 days until Hurricane season 2013!:)
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676. wxmod
http://www.guardian.co.uk/world/2013/mar/11/dead- pigs-chinese-river

Thousands of dead pigs found floating in Chinese river

This is from yesterday and I didn't have time to post it here. Hope you're not at the dinner table!

Member Since: October 4, 2011 Posts: 0 Comments: 1738
That is good rain in FL
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12Z GFS ENSEMBLE the ones that have it



This one is at 384HR
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Quoting ScottLincoln:

It's not Jim's job to "win people over." The science is the truth regardless of what Jim does. If you are going to make decisions on science based not on the science itself but on what Jim does or what you think Jim does, then that really says more about you than anything - or anyone - else.

Of course you can replace "Jim" with any person you wish and it would still be accurate.


I have to disagree..I'm going to even use one of the greatest scientists to prove my point in "do as I say"...

When Louis Pasteur who I can say is not Jim invented the process of Pasteurization, did he continue to drink the sour milk that wasnt pasteurized..no he led by example and dranked his own discovery which in turn led to others to adopt the milk we know of today..my point is Louis, Jim, You or I cant put ideas out there for others to commit to if one is not even following them..
Member Since: August 19, 2006 Posts: 13 Comments: 14451
Quoting MAweatherboy1:
18z GFS showed a rather curious system form over the Gulf of Mexico at the end of the run today. It starts out as a weak low here:



Then becomes a slightly stronger storm as it approaches and crosses over FL:







Is there any way the system depicted there could be tropical/subtropical? Or am I just way to anxious for hurricane season, lol?
Looks like the "Storm of the Century" wants to make a return.
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Quoting ncstorm:


then you will never win people over to further your cause if you yourself are not in the trenches proving your commitment...isnt that the whole objective to up the numbers in believers and have them vote in legislative?

It's not Jim's job to "win people over." The science is the truth regardless of what Jim does. If you are going to make decisions on science based not on the science itself but on what Jim does or what you think Jim does, then that really says more about you than anything - or anyone - else.

Of course you can replace "Jim" with any person you wish and it would still be accurate.
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Quoting VR46L:


Rookie , I never meant a slight on you , I really didn't !

Its just that I am of the opinion that when people talk of reducing CO2 they really should in their own life practice what they preach . And I don't believe it is trollish , I have seen several good weather bloggers ask this Question , But you are one of the few that will disclose . I believe it sets an example and leans more credence to your argument. Personally I read your posts and take them on board . To me you are an example of you can catch more flies with honey than vinegar (ie People who are not believers that it is 100% man fault would be more inclined to read your point of view than those who tend to be insulting and patronizing)

The "argument" doesn't change regardless of how the messenger acts. Although it certainly makes sense for someone to do as they say (and is frustrating when they don't), it really has very little to do with climate science (or any science, for that matter).

Science is the truth regardless of whether or not someone believes it to be true, and focusing on whether or not a messenger is doing something you think they should be doing is really more a distraction than an actual discussion of what the science says. This is why it could be considered trollish behavior - it borders on ad hominem, which is not a logical argument.
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668. VR46L
Quoting Levi32:
If only we could live in the world of the 15-day GFS forecast. I would love to see this. Look at the high-quality moisture this thing would be tapping into.



I think Most of Florida would like to see it, as it would hardly be tropical . I noticed its cold core .... but its so late in the GFS forecast ..It would need to keep appearing to be believed!!


Anyway Good Night Folks!
Member Since: March 1, 2012 Posts: 0 Comments: 6832
Quoting interstatelover7166:
yes


Oh, yes! Cleverbot! I will have to give it another try. Thanks!
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poss event detected

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Quoting Neapolitan:
When it comes to empirical science, I guess I've never understood those who say, "I'd believe in or support X, but some of the people who do say mean things sometimes, so I just can't." As humans, emotions obviously play some part in every decision we make. But deciding whether we support, say, climate change, or evolution, or the Big Bang, or the existence of black holes--really shouldn't be based upon whether we've felt slighted by someone who does, or whether someone who does was hypocritical in our eyes. (And vice versa, of course.) No, it should be based solely on whether we agree with the preponderance of the evidence: the mountains of observational data collected by thousands of people over many years, along with the peer-reviewed interpretations of those data. Nothing more.

Example: I've talked with some very obnoxious types who, like me, are firm supporters of the scientific consensus that cigarette smoking causes lung cancer. I mean, very obnoxious types, people with whom I'd rather not waste one minute of my time. But that fact doesn't make me want to run out and smoke a carton of Marlboros. That would be tremendously illogical, no?

One's scientific "belief" (for lack of a more fitting word) should always stem from evidence, not emotion.


then you will never win people over to further your cause if you yourself are not in the trenches proving your commitment...isnt that the whole objective to up the numbers in believers and have them vote in legislative? how can you say emotions shouldnt be tied into this?..you are one of the most passionate posters on here about GW and saving the earth?..Scientists are humans last time I checked so unless you are some type of robot, then you display emotion every time you write a post here..you cant separate the two..It comes through in your writing..I hate to tell you but you care which I must inform you is an emotion..

also, I have seen your ideology of the cigarettes too many times..come up with a new one..
Member Since: August 19, 2006 Posts: 13 Comments: 14451
Quoting VR46L:


Rookie , I never meant a slight on you , I really didn't !

Its just that I am of the opinion that when people talk of reducing CO2 they really should in their own life practice what they preach . And I don't believe it is trollish , I have seen several good weather bloggers ask this Question , But you are one of the few that will disclose . I believe it sets an example and leans more credence to your argument. Personally I read your posts and take them on board . To me you are an example of you can catch more flies with honey than vinegar (ie People who are not believers that it is 100% man fault would be more inclined to read your point of view than those who tend to be insulting and patronizing)


No worries, VR46L. We have had enough conversations that I did not take anything in a negative way because I knew you do not intend it to be negative. You are inquisitive on many subjects and this will serve you well. Never be reluctant to learn more than what you know now. The best way I found to learn is through conversations with others. ... Talking to myself never got me anywhere that didn't involve men in white smocks and carrying butterfly nets. :)

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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.