Researchers predict global warming will cause an increase in frequency of Indian Ocean Dipole events

Jun 12, 2014 by Bob Yirka report
Positive Indian Ocean Dipole events cause devastating floods in many vulnerable east Africa countries. The 1997 positive Indian Ocean Dipole event resulted in several thousand deaths and displaced hundreds of thousands of people. The latest generation of climate models project that these extreme events are to occur more often under greenhouse warming. This image depicts the Gash River flooding in Kassala, Eastern Sudan, 2007. Credit: MOHAMED NURELDIN ABDALLAH/REUTERS

(Phys.org) —A team of researchers, led by Wenju Cai of CSIRO Marine and Atmospheric Research, in Australia has published a paper in the journal Nature in which they report that 21 out of 23 climate models they ran indicated an increased frequency of Indian Ocean Dipole events over the next century. The increase, the team also reports, will be due to the continuation of global warming.

Indian Ocean Dipole events are atmospheric phenomena that occur due to ocean temperature differences. They are characterized by peak sea surface temperature swings between the eastern and western basins. Positive phases of the cycle occur when warmer waters in the west lead to more rainfall there and cooler waters in the east lead to less rainfall. When this happens, land areas in the east such as Australia and Indonesia tend to undergo draughts, while those in the west such as parts of Africa undergo flooding. One example occurred in 1997 when smoke from fires in Indonesia blackened the skies across the region even as thousands of people were killed due to flooding in several African nations. In their paper, the authors of this new study suggest such occurrences are likely to happen much more often over the next several decades.

To come to their conclusions, the team examined 31 global and determined that 23 of them were capable of modeling rainfall in the Indian Ocean during both normal times and when there is a dipole event occurring. They ran the models first for the period 1900, to 1999 to see how well they could predict dipole events that actually occurred, then, encouraged by the results, ran the models again, this time for the period 2000 to 2099, under what they describe as business as usual conditions. They report that 21 of 23 models predicted an increase in the frequency of positive phase Indian Ocean Dipole events—the combined average predictions suggest the region will see approximately triple the number of such events over the coming century—from one every 17.3 years to one every 6.3 years. The business as usual conditions assume will continue to increase at their current pace.

If such predictions come to pass it could mean an increase in fires in eastern countries, but more devastating perhaps, an increase in flooding in some of the poorest parts of the world, which would likely be made even worse in coastal areas as sea levels are predicted to rise during the same time period.

Explore further: Indian Ocean phenomenon helping to predict extreme weather

More information: Increased frequency of extreme Indian Ocean Dipole events due to greenhouse warming, Nature 510, 254–258 (12 June 2014) DOI: 10.1038/nature13327

Abstract
The Indian Ocean dipole is a prominent mode of coupled ocean–atmosphere variability, affecting the lives of millions of people in Indian Ocean rim countries. In its positive phase, sea surface temperatures are lower than normal off the Sumatra–Java coast, but higher in the western tropical Indian Ocean. During the extreme positive-IOD (pIOD) events of 1961, 1994 and 1997, the eastern cooling strengthened and extended westward along the equatorial Indian Ocean through strong reversal of both the mean westerly winds and the associated eastward-flowing upper ocean currents1, 2. This created anomalously dry conditions from the eastern to the central Indian Ocean along the Equator and atmospheric convergence farther west, leading to catastrophic floods in eastern tropical African countries13, 14 but devastating droughts in eastern Indian Ocean rim countries. Despite these serious consequences, the response of pIOD events to greenhouse warming is unknown. Here, using an ensemble of climate models forced by a scenario of high greenhouse gas emissions (Representative Concentration Pathway 8.5), we project that the frequency of extreme pIOD events will increase by almost a factor of three, from one event every 17.3 years over the twentieth century to one event every 6.3 years over the twenty-first century. We find that a mean state change—with weakening of both equatorial westerly winds and eastward oceanic currents in association with a faster warming in the western than the eastern equatorial Indian Ocean—facilitates more frequent occurrences of wind and oceanic current reversal. This leads to more frequent extreme pIOD events, suggesting an increasing frequency of extreme climate and weather events in regions affected by the pIOD.

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Shootist
2 / 5 (20) Jun 12, 2014
Climate Cultists
Has the desperate global warming crusade reached its Waterloo?

The climate change crusaders, who have been at it for a quarter-century, appear to be going clinically mad. Start with the rhetorical monotony and worship of authority ("97 percent of all scientists agree!"), add the Salem witch trial-style intimidation and persecution of dissenters, and the categorical demand that debate about science or policy is over because the matter is settled, and you have the profile of a cult-like sectarianism that has descended into paranoia and reflexive bullying. Never mind the scattered and not fully suppressed findings of climate scientists that the narrative of catastrophic global warming is overstated, like nearly every previous predicted environmental apocalypse.

http://www.weekly...401.html
Shootist
Jun 12, 2014
This comment has been removed by a moderator.
Landrew
1.7 / 5 (11) Jun 12, 2014
Where's this warming going on now? Shouldn't all the cooling eventually be tallied also?
Egleton
2 / 5 (4) Jun 12, 2014
Pot calling the kettle black.
Stalinist propaganda technique #5 "Always accuse your enemies of your own crimes."
orti
2.6 / 5 (10) Jun 12, 2014
A very good article Shootist. Wish more would read it.
Captain Stumpy
4.2 / 5 (15) Jun 12, 2014
"The polar bears will be fine" - Freeman John Dyson FRS
@shootist troll/spammer
"No balloon and no aeroplane will ever be practically successful."
-William Thomson, 1st Baron Kelvin
If you *have to* pick a genius scientist as your contrarian idol, a towering giant of Lord Kelvin's stature beats the pants off dinky wee Freeman Dyson. -PinkElephant

sometimes smart people are WRONG
your spam link is irrelevant given that your link comes from an agenda driven website and has all the same relevance here as this: https://www.youtu...Qp-q1Y1s

so... since you can't post science, and ya cant think and comprehend the studies being made, then you get paid for what? FUD?

do you get paid per post ?
MandoZink
3.4 / 5 (10) Jun 12, 2014
The climate change crusaders, who have been at it for a quarter-century, appear to be going clinically mad. Start with the rhetorical monotony and worship of authority ("97 percent of all scientists agree!"), add the Salem witch trial-style intimidation and persecution of dissenters, and the categorical demand that debate about science or policy is over because the matter is settled, and you have the profile of a cult-like sectarianism that has descended into paranoia and reflexive bullying. Never mind the scattered and not fully suppressed findings of climate scientists that the narrative of catastrophic global warming is overstated, like nearly every previous predicted environmental apocalypse.

You neglected to mention Hitler. There is an appropriate Nazi analogy begging to be expressed here.

A very good article Shootist. Wish more would read it.

Excellent article. Well condensed example of confirmation bias for a denialist. And from a properly neoconservative source.
antigoracle
1.9 / 5 (14) Jun 12, 2014
......sometimes smart people are WRONG
........
do you get paid per post ?
-Cap'n Stunty
More importantly, the dumb ones like you, are NEVER RIGHT.
I would not ask if you get paid for your posts, because no one will waste their money like that.
MR166
1.9 / 5 (14) Jun 12, 2014
"A team of researchers, led by Wenju Cai of CSIRO Marine and Atmospheric Research, in Australia has published a paper in the journal Nature in which they report that 21 out of 23 climate models they ran indicated an increased frequency of Indian Ocean Dipole events over the next century. The increase, the team also reports, will be due to the continuation of global warming."

How many of those 21 climate models have had correct temperature predictions over the last 20 years? None that I know of! This is a typical garbage in equals garbage out waste of computer time.
Grallen
3.9 / 5 (11) Jun 12, 2014
I have a theory that it would cost very little to flood all sites that report on climate science with crazy posts to make there appear to be an illusion of conflict in the topic.

Shootist could help us create a good estimate of how many people it takes by providing the number of people working in his outfit and if all posts here are by his outfit... But I think revealing that information would hurt his employers agenda, and probably cost him his job...
MR166
2 / 5 (12) Jun 12, 2014
Grallen with the utter lack of success of the climate models, how can you possibly think that the "science is settled"? Healthy science requires dissent in order to progress.
MR166
2.1 / 5 (11) Jun 12, 2014

Grallen
Science welcomes dissent whereas a political movement does not.

Climate science hates opposing views.

"If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck."
malapropism
3.7 / 5 (9) Jun 12, 2014
Regardless of whether you are a climate change advocate or denier, surely a study such as this has value simply because it has made a scientifically-based prediction arising from a number of models.

Predictions like this one are, by their nature, testable and obvious in outcome in hindsight; admittedly the test of this prediction's success might only come about in or after 2099 by which time the debate may be a moot point but, nevertheless, many commenters here (on both sides but it seems more especially on the denier side) have decried the lack of prediction and testability of the climate models - here is one. So why are you all so upset about it?
del2
5 / 5 (2) Jun 13, 2014
"When this happens, land areas in the east such as Australia and Indonesia tend to undergo draughts,"
Yes, it can get draughty here in Australia; we also get droughts.
ubavontuba
1.7 / 5 (11) Jun 13, 2014
Regardless of whether you are a climate change advocate or denier, surely a study such as this has value simply because it has made a scientifically-based prediction arising from a number of models.
Well, so far climate predictions have generally failed miserably. Why should we expect this one to be any different?

Predictions like this one are, by their nature, testable and obvious in outcome in hindsight; admittedly the test of this prediction's success might only come about in or after 2099 by which time the debate may be a moot point but, nevertheless, many commenters here (on both sides but it seems more especially on the denier side) have decried the lack of prediction and testability of the climate models - here is one. So why are you all so upset about it?
Because repetitious failures don't seem to matter to these quacks.

runrig
4.1 / 5 (14) Jun 13, 2014


How many of those 21 climate models have had correct temperature predictions over the last 20 years? None that I know of! This is a typical garbage in equals garbage out waste of computer time.

All of them ......... As there is no "correct" temperature prediction, and to say there is shows staggering ignorance of the way models work.
Models, when, as climate ones do, are used in ensemble give error bounds for the range of predictions. The current global temp rise lies within them.
To expect any complex system to exhibit a constant and unvarying trend is beyond ignorant, it is wilful denial.
Sherrin
not rated yet Jun 13, 2014
"... Australia and Indonesia tend to undergo draughts". And then you have us believe they undergo chess or backgammon. Draught: noun

1. draughts, ( used with a singular verb ) British . the game of checkers.

Editor ... will you PLEASE correct this daft drafting error?
MR166
1.4 / 5 (10) Jun 13, 2014
Politicians are trying to add hundreds of billions to our energy bills in order to subsidize industries that are in their favor. Today's temperatures are right at the lower limits of the error bands of even the few best models. Basing any decisions on today's climate models is ludicrous. Thinking that the consensus of these flawed models is any more accurate than any individual one is scientifically ignorant.
al_hopfer
1 / 5 (8) Jun 13, 2014
As Einstein said, models should be made 'as simple as possible, but not simpler.'"

• In 1979 measuring the Global temperature switched from land based stations measuring temperature in 10,000's of thousands of locations - to a satellite network measuring radiation in the atmosphere and calculating (surface) temperature at millions of locations.

I would presume that that satellite network is more accurate. One would then, therefore, have to assume those readings to be either higher or lower than the given 100 year span of land based readings of temperatures data sets.

Global temperatures from 1979 to 1998 (that continues to this day) "ramped" up by 0.58 degrees C. Today's global average is still 0.58 degrees C above the 20th Century average.

What, would account for this, is not a ramp up but a jump from 1978 to 1979 (due to a more accurate measuring system) and then mathematical smoothing over the next 20 year,... to justify the calculated values for surface temperature.

Not a warming trend, just a more accurate reading, that required smoothing to make sense.

Smoothing. When give a reference of a given temperature (measured from 1880 to 1978) and a new and different method and technology used to then measure that same temperature (our Planet)... if a difference occurs, a sample of that difference (4-5%) is taken and added or subtracted to or from the reference.

That adjusted reference number now becomes the "temporary" new temperature (needing additional measuring and smoothing to become more accepted as a good temperature outcome.

If that new reading were higher, and those new readings continue to be higher (higher than 1978) you will see a ramping up (effect) until the new, and higher, actual value is reached. Which is what happened in 1998... and of course, continues to this day.

There never was a warming from 1979 to 1998... just a better, more accurate reading by the satellite network versus land based measurements (or possibly a less accurate number that is just too high.

This would also lead to the conclusion that readings taken in 1901 and 1920 and 1930 etc. were also not as accurate as today's more capable systems... and those temperature readings (data sets) should be adjust upward to get a more accurate global temperature trend over the past 135 years, not the bogus less accurate one referenced today by promoters of warming.
thermodynamics
4 / 5 (8) Jun 13, 2014
Al hopping idiot said:
Global temperatures from 1979 to 1998 (that continues to this day) "ramped" up by 0.58 degrees C. Today's global average is still 0.58 degrees C above the 2000 Today's global average is still 0.58 degrees C above the 20th Century average.

Smoothing. When give a reference of a given temperature (measured from 1880 to 1978) and a new and different method and technology used to then measure that same temperature (our Planet)... if a difference occurs, a sample of that difference (4-5%) is taken and added or subtracted to or from the reference.

That adjusted reference number now becomes the "temporary" new temperature (needing additional measuring and smoothing to become more accepted as a good temperature outcome.


Can you recall back to your days in middle school (it might have been a decade for your special needs) where they taught you what statistics are and how they can be used?

Probably not. Continued
thermodynamics
4 / 5 (8) Jun 13, 2014
Continued:

Smoothing can take place by choosing a large number of algorithms.

http://en.wikiped...moothing

I, generally, like to use a moving average algorithm - although if my data are not looking like they are distributed in a particular way, I can apply a cubic spline smoothing function.

if a difference occurs, a sample of that difference (4-5%) is taken and added or subtracted to or from the reference.


Only as a perturbation and is not present in all approaches (as you seem to think). In fact, it appears as though you really don't know what they are doing.

If you are thinking of adding a signal to attempt to extract it we do that all the time to indicate the "power" of our methods.

Also, don't confusing smoothing with perturbation.

Please tell us what algorithm you are thinking of other than moving averages or splines (which I have already addressed). I think you are just shouting bull. However, I am always glad to dig deeper.
Shootist
1.8 / 5 (5) Jun 19, 2014
"What I'm convinced of is that we don't understand climate." - Freeman Dyson

As a general rule, if Freeman Dyson doesn't understand something, you don't, either.
Captain Stumpy
3.7 / 5 (6) Jun 19, 2014
"What I'm convinced of is that we don't understand climate." - Freeman Dyson

As a general rule, if Freeman Dyson doesn't understand something, you don't, either.
just because YOU don't understand something doesn't mean NO ONE does...
scientists DO understand, and can prove their stance with empirical data like: http://theconsens...ect.com/

or http://blogs.scie...sagrees/
"No balloon and no aeroplane will ever be practically successful."
-William Thomson, 1st Baron Kelvin
If you *have to* pick a genius scientist as your contrarian idol, a towering giant of Lord Kelvin's stature beats the pants off dinky wee Freeman Dyson.

http://qz.com/163...n-worse/

considering you don't post relevant ANYTHING, nor do you contribute to the science, the talks, etc... this is for you, shooty
https://www.youtu...Qp-q1Y1s