gland cold water
Not sure what the cause of this is, victor. Current SST anomalies show that it's around 2 degrees cooler than usual in the east Java region right now (see chart below).
The springsuit comments are obviously biased, coming from people who live there and surf year-round. If you're travelling from Australia it'll still be very warm.
I had two mates just come back from S Sumatra and Bali two weeks ago and they said the water was genuinely cold. At times they wanted a springy and with the wind factor some days, they would only spend 3/4 - 1 hour in the water at a time. I thought they were bullshitting at the time, but I have heard similar reports of late.
Very interesting stuff - I'll do some investigating and see what I can find.
I was there for 3 weeks in June and found nothing but normal Indo. From what I hear it has been 4 - 6 weeks now. I've never experienced it and obviously can't explain it. I just put it down to some stong deep water upwellings/currents moving in. I had similar things happen on the east coast Aus right up into the GBR from time to time and think its just one of those things that happen occasionally.
If governments would spend just a fraction of what they spent on space exploration and put some of that into ocean exploration, we may get more of an idea. But that is for an other forum!
Just got back from bali. A couple of days last week the water did feel cold - a springy would have been good in fact a few crew had them on. Last few days was warmer again.
southey hit the nail on the head. It is the IOD. But it is the Positive IOD that causes the cold waters (negative SST anomalies, bit confusing) and a raised thermocline south of indo... It is the Indian Oceans internal climate variability such as ENSO in the Pacific. Fitzy you would be right in that temps seemed normal in June as the IOD generally peaks over the September-November period, seasonally locked due to the seasonal pattern of equatorial and monsoonal winds. As southey noted we saw similar circumstances in 2006 but the biggest events were in the Spring of 1994 and 1997. Waters would be much warmer still there in Vic at the moment, I would love to be over there whinging about temps in the 20s!!
we were at one palm in the first 1/2 of september and were amazed the water was so cold . we had 3mm steamers on hand for the protection but found we could comfortably wear them all day due to the water temp.
As southey noted we saw similar circumstances in 2006 but the biggest events were in the Spring of 1994 and 1997.
Quite odd that all of these time events coincided with strong El Nino, and yet we're in a moderate La Nina at the moment. As Southey pointed out, one would have thought that it was related to the IOD and ENSO??
@ Evan ,
Cheers for the correction ( Positive IOD ) . I have spent so much time writing about this elsewhere with positive and negatives that I've done myself over .... I also accidently deleted my original post , so after frustratingly re constructing it I failed to re-read it .
Dons' onto my line of thought about it being both ENSO and IOD , and I've been focusing on this regions SST's quite heavily trying to correlate exactly what types of influences drive each and if there is more of a teleconnection between the two than most Oceanographers and Climatologists give note to . Where the ENSO trend sits in a PDO timeline is of closest interest . And all of this was fueled by a hunch that Planetary alignments and King tides could influence this . But thats for another day and thread ....
Strange how surfing maxing - too big Deserts ( including MASSIVE swell heights change with tide ) and experiencing upwelling in the same season gets the mind wondering about ocean hydraulics...
Positive IOD normally correlates with El Nino and vice versa though it's not a rock solid correlation.
Also, I'd say we're in the process of transitioning to La Nina right now, certainly not anywhere near a fully fledged Nina state.
The IOD doesn't "cause" the upwelling/cold pool off Sumatra/Java, it is merely a measure of the difference between temps there and off Kenya/Somalia.
Monsoonal effects/upwelling and the Indonesian Throughflow are the causes of the upwelling but it's easy to get caught in chicken and egg arguments about which causes what.
Great to hear your thoughts Southey.
this link might be useful
Great link there "b".....definitely some very noticeable cooler water just off the coast of Java, particularly back in September. Water looks to have warmed slightly based on latest charts.
Given the very close proximity to the Java landmass, I'm wondering if it's some form of Coriolis effect similar to what the east coast of Aus get's this time of year with relentless NE winds for 3 days or more.
Anyone checked out what the trades have been doing up near Java in September, compared with say other months of the year?
This article explains it quite well and I'm thinking that the coast of Java is pretty parallel to the constant E/SE trades and hence through Coriolis and Ekman Transport, the coastline of Java sees upwelling.
September probably has this occuring more than other months due to the mid-latitude semi stationary high pressure systems increasing the E/SE trades off Java. Although my limited knowledge would have expected this to occur more so in La Nina years, which doesn't appear to be the case looking at the years quoted above by Southey (and supported by the SST pics found by "b".
Here's a research paper which essentially says this is simply a seasonal upwelling event.
Nice find Ben. Supports what I thought, even with broken English.
unfortunatley that link doesn't work for me .
i do have a link to agoogle based satellite product but thats at home .
thermalb , good local paper ... ( supporting gyres and so forth with offshore evidence )
fr76 , agreed chicken and egg seems to be flavour of the decade especiallty in climate circles . No doubt winds , parallel to coasts cause ekman spiral through coriolis . But generally the walker circulation will cause increased strength winds ( including IOD )!? vicious circle .
The one thing that is key is ITF and seeing that upwelling tends to peak after trades or monsoonal winds have lost some sting then no doubt the ITF's increased transfer due to Nth -Sth seasonal height anomalies including spring tides would have to have more of an influence than all the current papers give rise to ( pardon the pun ) ... Ekman is the simple explanation , but local perculiarities must play a role .
Of note as mentioned previously The extra flows adjacent to the straits seems to strengthen the ekman spiral/cycle , and maybe even jumps/kick starts it .???
when I was in G'lad in 2005 a skinny Kiwi ripper was wearing a 3/2 mm!! I thought he was a little soft for a kiwi... but my 2 mm neo vest was very happily donned most sessions, (and I had just escaped the chilly southern ocean....
Furthermore, I can support Southy in his description of the southern Sumatran cold water link and the Indian Ocean Dipole and the Pacific Warm pool.
I'm a working within a group that undertakes tuna research in the Indian Ocean and have seen how heavily the upwelling can effect the biological communities off the coast of Sumatra - normally a fairly productive fishing zone, but IOD events in the Eastern Indian Ocean are known to cause deep water upwelling off the coast of Sumatra, bringing very cold, oxygen poor water from the bottom of the ocean to the surface (and resulting in poor tuna catch) - in addition to the points that southy made, the process is thought to also be associated with very long period (10s of years) internal ocean waves (Rossby waves) that propagate from East to west along the equator and return on the boundaries of the Indian ocean. (kind of like pushing the bathwater between you legs when you were a grommy and watching the water return along the edge of the bath - only on a much bigger and slower time scale) anyways... that shines a bit of light on the cold water in Sumatra ... The cold water in G'land is a more common event and is more likely due to upwelling associated with the IFT as Southy mentioned. Same thing can happen in Nusa Lembongan on occasion. My guess is that the key factors are due to the piling up of hot water in the Western Pacific wanting a quick exit.. and this water pours through the Bunda strait (and around the many islands in the archipelago) and causes all sorts of turbulence (Eddys, upwellings, downwellings etc), similar to rapids in a stream that cause "stoppers", plumes and whirpools just on a different spatial and temporal scale. Like southy said, very interesting.. you can find out more by digging around CSIRO website.. www.csiro.au/resources/AustralasianOceanCurrents.html#3 and chasing up scholarly papers or press releases by Dr Susan Wijffels and Gary Myers
A good example of this ( although only the top half of it would normally be exceeding 25 degs ) , was the Leeuwin Current this year . Places as far south a Yallingup were recording SST's of close to 26 deg as late as May/June . Last Years Stong Negative IOD combined with Strong Nina gave higher surface heights and temps across Northern Aust . SO the Leeuwin was loaded this year ...
The Leeuwin is a rare poleward west coast current , There are only two others that i know of , one being quite short along Mexico ( although not quite as strong or regular ) The other being the tail end of the Gulf Stream (current) which runs up towards Scandinavia . Again this is no where near 25 deg's but the difference it makes in Land temps is remarkable .Have a look at how far north Germany's Beaches are and to think they can actually swim there comfortably in Summer .!
been hearing lots this season re g,land and cold water,is this a normal,a regular cold water current?surf camp reports recommend a springsuit at times,a springy in indo? another report from sth sumatra freezing at times 17deg.any explantion thermal ben or others.thinking that wearing a wettie in indo would be for reef cut protection only not cold water.