El Nino and Australian Swell Patterns

Craig Brokensha picture
Craig Brokensha (Craig)
Swellnet Analysis

Among the international surf community there's been excited chatter about the current El Nino pattern and its prospects for good surf. At present, we're in a strong El Nino and the scientific community is giving it a 90% chance that it will continue into the Northern Hemisphere winter.

Much of the aforementioned excitement is coming from mainland US and Hawaiian surfers because the link between El Nino and swell has been extensively studied there – El Nino seasons are often very good indeed. But what does it mean for the surf in Australia?

Unfortunately there're limited studies on the Australian region, but the little that is known suggests that El Nino doesn't have much influence on our East Coast, especially compared to La Nina when the Coral Sea is much warmer and conducive to cyclone activity.

During El Nino, easterly trade winds traversing the Pacific Ocean weaken (and sometimes even reverse), the result is that warm water 'piles up' in the Eastern Pacific Ocean adjacent to South America.

In the northern hemisphere, El Nino causes the storm track to travel closer to the equator thereby increasing storm and swell activity for Hawaii and California. This shift in storm track further south also results in less swell being aimed into the Pacific North West, ie Washington, Oregon, and the Canadian coast.

During La Nina, however, the trade winds are stronger than normal, warm water piles up in the Western Pacific and Coral Sea increasing the potential for tropical cyclone activity on our side of the ocean. There's also the flow on effects into autumn and winter from warmer than normal water pushing south with the East Australian Current, providing the catalyst for low pressure systems to spawn in the Tasman Sea due to the interaction with cold polar bursts from the south.

Even though the effect of La Nina and El Nino on the Australian wave climate are limited, these diagrams of the Pacific basin reveal an interesting picture. They illustrate the difference in mean significant wave height from the norm when under La Nina conditions (top) and El Nino conditions (bottom).6e7ae6fff44fb3735079676fbd8aa713120e6f8afc0b6ae504pimgpsh_fullsize_distr.jpg

What's clearly evident during El Nino is an increase in significant wave heights across the North Pacific, as is well documented and observed, but a noticeable drop in wave height across south-western Australia and Indonesia.

Now, besides the large Indian Ocean swell at the end of June, the Indonesian season has been very slow, especially compared to last year's standout season, and that matches the data in the diagram.

Victoria, however, has seen non stop-swell and pumping waves across the Surf Coast, falling in line with the red shading in that region just west of Tasmania.

Tahiti is another region which shows more size through El Nino, and the year thus far has been consistent with numerous large swells hitting Teahupoo.

Looking again at the La Nina diagram, we can see the Western Indian Ocean painted red showing higher than normal significant wave heights, as is the Australian East Coast, while the North Pacific shows a blue hole of lower than average wave heights.

For many years there's been a mistaken assumption that El Nino increases the swell potential everywhere, yet these diagrams show that to be untrue. So keep these diagrams in mind if you're booking a surf trip and want the best chance of swell. First of all check if you'll be travelling during El Nino and La Nina and then choose your destination accordingly. //CRAIG BROKENSHA

Chart: The wind-wave climate of the Pacific Ocean

Comments

donweather's picture
donweather's picture
donweather Wednesday, 5 Aug 2015 at 1:25pm

You mention the plots in the indian ocean but the plots provided above don't include the indian ocean. Can you also post the indian ocean plots. Also, what's the scale measured in on the RHS of the plots? Metres?

Craig's picture
Craig's picture
Craig Wednesday, 5 Aug 2015 at 1:35pm

No charts for the Indian Ocean sorry Don (would love to see the entire globe myself), just that eastern extent as shown, and yes metres.

donweather's picture
donweather's picture
donweather Wednesday, 5 Aug 2015 at 4:14pm
Craig wrote:

No charts for the Indian Ocean sorry Don (would love to see the entire globe myself), just that eastern extent as shown, and yes metres.

So your comments in your article above about Indo and the Indian Ocean are only based on the plots you've included above. Hmmmmmm, kinda need to see the whole Indian Ocean in order to fully see the effects on places like all of Indonesia, Maldives, Sri Lanka etc etc as they all have very different swell windows.

Also, if the above anomalies are in metres then they're saying that the maximum difference in "mean significant wave height from the norm" between La Nina and El Nino is only 0.4m!!!! Seems Sweet FA difference IMO. So El Nino produces 0.2m mean significant wave height more than the norm and La Nina produces 0.2m less mean significant wave height than the norm? We're talking 20cm here folks on a Hsig.....seems feck all?

Craig's picture
Craig's picture
Craig Wednesday, 5 Aug 2015 at 4:33pm

When referring to Indonesia, yes eastern Indonesia more so than further west where we can't see.

The diagram is a simple and great representation of the differences during each ENSO phase.

I think trying to make anything of the actual size difference given by the scale is missing the point.

Here's a better image for you showing the correlation between monthly mean significant wave height anomalies (after annual cycle is removed) and the Southern Oscillation Index. A strong negative correlation is seen with El Nino.

Blue shade means that the more negative the SOI (El Nino) the greater the increase in mean significant wave height, and vice versa, ie at the same time the red areas will see a drop in mean signifcant wave height.

During La Nina, positive SOI, the blue areas will be smaller, and red larger.

ACB__'s picture
ACB__'s picture
ACB__ Wednesday, 5 Aug 2015 at 2:40pm

I'm spending a few months in northern south, and central America from December through to July next year.

Now while the graph and history suggests El Nino in Central America can produce more storms and swell, I understand it will mean more rain and worse rather than better conditions. Do you think this will be the case?

mick-free's picture
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mick-free Wednesday, 5 Aug 2015 at 2:50pm

Be sure to keep us informed of your travels ACB would be sick to see what you score surf wise

ACB__'s picture
ACB__'s picture
ACB__ Wednesday, 5 Aug 2015 at 2:57pm

Will do mate..

Packing everything up into storage, quitting the 9-5, getting away from the city and routine and simply exploring the continent. Starting in Lima Peru and am aiming to finish in Mexico city. Traveling mainly by land. I was planning on starting a thread soon on anyone who has any experience with central America cause I plan on surfing as much as possible...

mibs-oner's picture
mibs-oner's picture
mibs-oner Wednesday, 5 Aug 2015 at 6:14pm

I remember an old rip curl search vid with the hog called chocolate barrels and liquid trips I think? During and El Niño event. They scored so I assume you will.... Hopefully anyway

Craig's picture
Craig's picture
Craig Wednesday, 5 Aug 2015 at 3:00pm

Hi ACB, this may be helpful, shows excessive rainfall on the Caribbean side with the associated winds and weather, and dryer out on the Pacific side..

Craig's picture
Craig's picture
Craig Wednesday, 5 Aug 2015 at 3:02pm

"In Central America, El Niño leads to excessive rainfall along the Caribbean coasts, while the Pacific coasts will remain dry. Rainfall increases on the coasts of Ecuador, the northern part of Peru, and southern zones of Chile. In Ecuador, Peru and Bolivia there will be drought in the mountainous and Andean zones, implying retreat of glaciers with subsequent changes in the availability of water and in local biodiversity. In Colombia, Venezuela and Guyana precipitation will tend to be reduced, leading to drought in the Brazilian northeast. In Argentina, Paraguay and Uruguay rainfall will increase and there will be a rise in temperatures in the southern part of Brazil. "

Stu2d2's picture
Stu2d2's picture
Stu2d2 Thursday, 6 Aug 2015 at 1:16pm

If the Eddie runs then make sure you land in the galapogas islands about 3 days later... I was there in 09.

Craig's picture
Craig's picture
Craig Thursday, 6 Aug 2015 at 1:27pm

Wow, lucky fella to even visit the Galapagos, let alone surf there!

ACB__'s picture
ACB__'s picture
ACB__ Thursday, 6 Aug 2015 at 1:59pm

Will be in the Galapogas in early January so I guess it's in the swell window! Don't think I'll be taking boards out to the island. Maybe one of the charter boats will have one I can pinch for a few hours. I understand you can rent stuff in Puerto Baquerizo Moreno.

Stu2d2's picture
Stu2d2's picture
Stu2d2 Thursday, 6 Aug 2015 at 9:01pm

Ur crazy not to take a board out there..

I was in the north of Peru and saw the swell pop up, got a ticket and went. Most amazing swell I have ever seen anywhere.

ACB__'s picture
ACB__'s picture
ACB__ Friday, 7 Aug 2015 at 9:02am

How did you get around out there? Did you do a boat tour or can you surf off the main islands?

Cheers!

Stu2d2's picture
Stu2d2's picture
Stu2d2 Friday, 7 Aug 2015 at 1:33pm

Stayed in San Cristobal and surfed the local waves.. there are probably loads of waves in the outer islands but you aren't allowed to surf them - "visual pollution" to the "animal watchers" or something like that. Maybe there is a surf charter? If it was me I would only go there on a hit and run mission if a solid swell showed up. Buena suerte..

halleys-comet's picture
halleys-comet's picture
halleys-comet Wednesday, 5 Aug 2015 at 2:48pm

Hi Craig, do you any info or links to Indian Ocean El Nino type phenomena? currents, temps etc?
Last winter Indo and NW WA had awesome swell and wind combos, this year it's the opposite (excepting 2 swells early July), we've another swell due in WA on Sunday, but thats the first decent swell in a month. I'd love to know more...
I do appreciate there is a dearth of data about the Indian Ocean, but thought you may have some info?
cheers

Craig's picture
Craig's picture
Craig Wednesday, 5 Aug 2015 at 3:04pm

Not on hand, will have to do more research. The Indian Ocean Dipole would have to be looked into as well.

surfari63's picture
surfari63's picture
surfari63 Wednesday, 5 Aug 2015 at 6:28pm

Hi Craig - Maldives seems to be having a good run this year with highs sitting off Western Australia and sending SE swell that way fairly regularly ( next week being probably the big one of the year so far) . Do you think this could mean El Nino results in more consistent SE swell there? Or is the info still unclear ?

penmister's picture
penmister's picture
penmister Wednesday, 5 Aug 2015 at 7:23pm

Eating tacos drinking corona and getting your El nino on........

stunet's picture
stunet's picture
stunet Wednesday, 5 Aug 2015 at 7:33pm

penmister wrote:

Eating tacos drinking corona and getting your El nino on........

That statement ain't quite so appealing when translated from Spanish.

Eugene Green's picture
Eugene Green's picture
Eugene Green Wednesday, 5 Aug 2015 at 9:45pm

Pretty unusual weather for WA so far this winter. Sunny days, small swells, light winds. Makes for a difficult argument against the reality of climate change that's for sure.

davetherave's picture
davetherave's picture
davetherave Wednesday, 5 Aug 2015 at 11:18pm

climate is always changing, although it does change periodically as to be expected as the whole process is dynamic.
Without doubt, the water temp in Tweed River is the warmest it has been in winter for the 26 years i have been swimming in it weekly.
Things go in cycles, no right or wrong, or usual or unusual, just the flow of life and just maybe we are entering a cycle where variability is greater than what has been recorded.

longboarder420's picture
longboarder420's picture
longboarder420 Thursday, 6 Aug 2015 at 2:50pm

No dave the earth is dying and mining is to blame, Well mostly.....

If you surf and you work in the mines, I hate you, Goes agaisnt the grain so to speak,

wellymon's picture
wellymon's picture
wellymon Thursday, 6 Aug 2015 at 3:04pm

No Davo does not surf and does not work in the mines.

Only in your mind. He loves you......!

davetherave's picture
davetherave's picture
davetherave Friday, 7 Aug 2015 at 7:35am
wellymon wrote:

No Davo does not surf and does not work in the mines.

Only in your mind. He loves you......!

thanks for that welly, welly loves the wallabies right!!!!
the earth is not dying, and mining has long been a part of earth's history, the planet does not mind sharing it's riches, but pollution is another matter.
i think we have to be aware that the past cyclical data may no longer be as accurate as it once seemed to be- also the records are not that old- and just maybe we are covering new territory here.
been bodysurfing d-bah- small but fun.

longboarder420's picture
longboarder420's picture
longboarder420 Monday, 10 Aug 2015 at 12:54pm

I also love Dave ,

See you guys at Defqon 1 sydney I hope , :) :) :)

AndyM's picture
AndyM's picture
AndyM Saturday, 16 Jan 2016 at 8:14pm

The best scientific minds in the world disagree with you Dave!

erikb's picture
erikb's picture
erikb Friday, 7 Aug 2015 at 2:51am

Great article!
Any thoughts/theories/facts on how (if any) the el nina and la nina patterns influence the north atlantic? Can i expect anything to happen or not, both in the surf and snow?

Craig's picture
Craig's picture
Craig Friday, 7 Aug 2015 at 6:56am

Thanks Erik! Will try and have a look when I get a free minute.

freezin's picture
freezin's picture
freezin Monday, 10 Aug 2015 at 8:59am

Does this mean more swell activity below Tasmania and around NZ?

Craig's picture
Craig's picture
Craig Monday, 10 Aug 2015 at 9:11am

Yes, it appears so.

wellymon's picture
wellymon's picture
wellymon Monday, 10 Aug 2015 at 12:55pm

And snow;-)

thermalben's picture
thermalben's picture
thermalben Thursday, 17 Sep 2015 at 1:06pm

Mark Sponsler from StormSurf just wrote (on FB):

"El Nino 2015 - Kelvin Wave #3 is just starting to erupt west of the Galapagos with water temps 4-5 degs C above normal (top image), with much warmer anomalies still poised deeper in the ocean (lower image). Nino3.4 temps today are at +1.974 degs C above normal. Once those new surface anomalies head west driven by trades, Nino3.4 temps will blow up. Our strong El Nino sure looks headed towards 'Super' status."

the_b's picture
the_b's picture
the_b Thursday, 17 Sep 2015 at 4:01pm

Wondering if you could do a "spells" analysis of the waverider buoy data to determine differences between el nino and la nina wave climate e.g. average length of time when Hsig > 2m during an el nino/la nina period, and average length of time between such spells (i.e typical duration of flat spells). This is what we would often do when analysing rainfall climatology for water resources.

windjunky's picture
windjunky's picture
windjunky Saturday, 16 Jan 2016 at 5:41pm

Thanks Craig - fascinating maps.
What dataset was that from - and hence how many past ENSO events did it cover?
Cheers,
ABW

Vic Local's picture
Vic Local's picture
Vic Local Sunday, 17 Jan 2016 at 12:25pm

Just got back from Indo and it's dry dry dry. Very light winds and no sign of the howling westerlies that often happen in Dec/Jan.
Multiple days with light SE dry season winds which opened up the Bukit Peninsula. Surfed all the dry season waves in Lombok. Keramas was onshore very early in the mornings in December. All very unusual.
Never seen so many water trucks heading out to the Bukit Peninsula. It's basically run out of fresh water.

meremortal1255's picture
meremortal1255's picture
meremortal1255 Monday, 1 Aug 2016 at 12:00pm

everyone is talking about swells (height) but the fact is that on the south west coast of australia (big swells or not) there has been absolutely no power in the waves (very very slow waves hitting reefs) as opposed to the great punchy right-handers we used to get 4 years ago. what is going on? i'm a booger and i've surfed about 10X in the last 3 years as opposed to 5X per week at northies the previous 8 years. most boogers are complaining in this region. as i take off very very late it's almost no waves for me as they are either closing, very obtuse (with no free fall or sheer drop) or hollow on take-off. is this the same everywhere in the world at the moment as i need to move on if there's a spot pumping with steep super fast drops? heeeeeelllllppppp......

meremortal1255's picture
meremortal1255's picture
meremortal1255 Monday, 1 Aug 2016 at 12:06pm

ps and for those of you commenting on the environment stop the blame game. everything starts in the home so start planting your own tall trees, veg, fruit and nuts and stop eating supermarket food (you'll go mad if you continue eating plastic-wrapped preservatives and chems anyway - copper overload which is responsible for 99% of the western world's diseases). i live a plastic free life, re-recycle everything and use my charcoal from the fires in winter for medicine and my ash for fertilizer and keeping bugs away. it would be boring if i told you everything but my life doesn't allow me to use a mobile or pc often as i'm busy living life. no consumerism in my life! one of my majors was economics - it taught me alot......