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Old 16-04-2017, 13:53   #1
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Langkawi,Bali,Darwin,Cairns,Brisbane

Hi, a friend has just purchased a Selene LRC and we ( 4 sailors ) are embarking around 25th May from Langkawi to take the boat to Brisbane. Figure it will take a couple of months to do this trip. Would appreciate any advice that can be given, preferably by someone that has done any sailing in these waters. Any hazards to watch for ? Thanks for your time. Bill
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Old 18-04-2017, 07:02   #2
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

Bill99:

I guess you're familiar with the Asia-Australia monsoon system.


And I further guess you're aware that the southwest monsoon, the season of SW winds N of the Equator and SE winds S of the Equator, seems ahead of schedule this calendar year.


For the early spike in the SW monsoon, see: Monsoon Monitoring


That early spike already shows up in the Singapore NEA wind and wave forecasts, such as: Marine Forecasts | Significant Wave Height |


You'll note the SE winds on the Cairns to BNE leg. If you make it to Cooktown, it's always fun to visit the museum and read parts of Jimmy Cook's log, especially the bit that is the basis of the oft repeated advice that the easiest way to sail from Cairns to Brisbane is via Perth (unless you are lucky and pick a year with big mobs of northerlies, but usually not until late in the calendar year).


All of which is to say that I've done much the same passage before. And I don't think I'd start in late May. But I much prefer downwind legs. You may prefer a good beating.


I assume you and the rest of the crew have or will arrange in Singapore to get Indonesian visas. Always dress appropriately (no shorts or t-shirts) when visiting the Indonesian Embassy in Sinkers.


As for hazards, I'll nominate:


* in Indonesian waters, look out for coral unless in turbid waters and never assume that a local Indonesian knows anything about the draught of your vessel and the depth of their local waters. Indonesian paper charts, available through the Indonesian navy, are quite good.


* in Indonesian waters, especially if the SW monsoon continues to strengthen ahead of schedule, keep an eye out for squalls. Typically advertised in advance by a black bar on the horizon. Should you see one, reefing early and hard is the rule.


* in Indonesian waters, always fly the Indon courtesy flag. Smile at the Indonesian Navy guys even if they give you a blank unfriendly stare. do not expect an Indonesian naval vessel to give you right of way in Indonesia territorial waters.


* if the SW monsoon continues to strengthen ahead of schedule, you might even meet nasty squalls (barat or westerly squalls, also known as Sumatra squalls or line squalls because they could sink a ship of the line of battle) in the S part of the Malacca Strait.


* no request for a petty bribe from Indonesian officials will equal or surpass the Ned Kelly highway robbery practised by Australian quarantine, with their swingeing charges to remove garbage from your vessels and to check your vessel for fouling growth and termites.


* for that matter, carry the receipts from your most recent antifouling to show the Aus quarantine officials. It won't stop them charging you to run their underwater camera over your hull, but it may stop them ordering a haul-out at your cost.


* the Halfwit Dutton-led militarised Aus Border Force is a mix of young recruits who are not sure of what policy to apply and so prefer to treat you harshly, thugs who want to show off their militarised authority if they got out of bed the wrong side that particular day, and a few confident old hands who make professional judgments about you and your vessel. The first two categories are all to be more feared that the most unfriendly Indonesian navy personnel.


In summary, I nominate the weather, coral, Aus Quarantine Inspection, and Aus Border Force as the top hazards you're likely to meet.
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Old 18-04-2017, 20:45   #3
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

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And I further guess you're aware that the southwest monsoon, the season of SW winds N of the Equator and SE winds S of the Equator, seems ahead of schedule this calendar year.
Mea culpa. Instead of "Equator" that should read "ITCZ".

And, unless you are familiar with sailing through the Malacca Strait, Singapore Strait, and Indonesia, I should add a couple more hazards:

* in the Malacca Strait and inshore areas of Indonesia: be alert to the fishing practices of small scale inshore fishers, especially at night. Several fishing practices, among which is hanging a gill net so it is suspended a metre or two below the surface. Floats with pendant lines support the gill net. One or both ends of the gill net may be marked with a larger float and a flag on a bamboo pole. Sometimes the fishers sit with their boat at one end of the run of gill net. You've two choices: go around the run of gill net (which will likely be at right angles to the tidal current) or, if your draught is shoal, cross the net midway between two floats. In the Malacca Strait, one tactic is to aim to sail in the inshore zone (on the Malaysian side of the shipping channel), just outside the shipping channel but close enough to the shipping channel that you avoid much of the fishing activity.


* small scale fishers are casual (or too poor) to run nav lights at night. Others have red and green that show 360 degrees; others only run a white fluoro tube; and still others only turn on lights when they are changing direction of working on deck. Some GRP and wooden boats do not give a solid radar return.

* fishers, including trawlers, can sometimes act in ways that will keep your collision avoidance skills well honed. Crossing just in front of your bow is one of them.

* should you anchor overnight, you may meet fishers who want you to up anchor and move because they traditionally net that bay. It's their livelihood.

* after heavy rain onshore, you may meet flotsam trash, everything from plastic bags to logs.

* be alert when crossing the shipping channels and separation zone in the Singapore Strait. Always best to aim to do it in daylight, with VHF, AIS, and radar on. The frequency of traffic in the shipping channels is a measure of world trade activity - sometimes the channels are not busy, other times there is a steady march of cargo ships spaced 5 to 10 minutes apart. Also be alert for naval ships - SG, US, Indon. They'll see you before you see them (although the Sinkers navy has a sad record of putting a stealthy sub hunter boat across the bows of a cargo ship, such that the cargo ship cut the SG cutter in 2; the SG boat did not return a good radar signal because of its stealth design and too many of its crew were 'on watch' - shared responsibility was no responsibility without clear delegation to stbd watch, port watch, etc made)
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Old 18-04-2017, 23:07   #4
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

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* in Indonesian waters, especially if the SW monsoon continues to strengthen ahead of schedule, keep an eye out for squalls. Typically advertised in advance by a black bar on the horizon. Should you see one, reefing early and hard is the rule.

* if the SW monsoon continues to strengthen ahead of schedule, you might even meet nasty squalls (barat or westerly squalls, also known as Sumatra squalls or line squalls because they could sink a ship of the line of battle) in the S part of the Malacca Strait.
To add to that:

* A fair proportion of line squalls in the S part of the Malacca Strait hit pre-dawn. Anchor appropriately (not on a lee shore, a good scope ratio, power set the anchor, with protection from the W and SW as appropriate, good snubbing and anti-chafe gear).

* Lightning protection generally adds to confidence among the crew. Thunderstorms with big mobs of lightning are not rare around the edge of the ITCZ.

* A fair percentage of squalls in Indonesian waters hit in the late afternoon and early evening. If the Madden-Julian Oscillation is at a peak for the 'maritime continent' (as the Great Archipelago of maritime Southeast Asia is called), squalls can be multiple, spaced perhaps an hour apart. So relax not after one squall has passed. Keep checking the horizon for the tell-tale bar.

* radar detects line squalls. Long squall lines (line squalls are usually squall lines, not isolated t-storm cells) are close to impossible to move around. Having an idea of how much sea room you have to run before a line squall can be a good idea. Multiple line squalls can create a well developed sea to the point of requiring good steering skills.
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Old 19-04-2017, 00:10   #5
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

Bill, once you leave Indo, maybe at Fukfuk or similar, your going to have a difficult, on the wind passage against the trade winds. It can be done, but better later in the year. Happy to talk to you about it, I'm in Auckland, 0221539176 . Cheers
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Old 19-04-2017, 12:47   #6
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

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Bill, once you leave Indo, maybe at Fukfuk or similar, your going to have a difficult, on the wind passage against the trade winds. It can be done, but better later in the year.
I agree with Matt. Starting from Langkawi in late May is the wrong time, unless you are looking for a good beating.

Look at surface wind shown by the webpages delivered by Singapore's National Environment Agency:

1. Point your browser to: Marine Forecasts | Surface Winds |

2. Your browser will open to the Significant Wave tab. Study it and then click the Surface Wind tab.

Langkawi is currently in the final stages of what can be called an Intermonsoon, characterised by light winds with the potential to shift from NE to SW. And the potential of thunderstorms if not stiff squalls.

According to the canonical climate schedule, Langkawi and the rest of MY will move from the Intermonsoon to the SW monsoon sometime in June.That means the ITCZ will be N of Langkawi, and SW winds will be dominant from the ITCZ south to the Equator. S of the Equator, SE winds will rule. As I wrote earlier, the transition to the SW monsoon may be ahead of schedule this year. Or not. Weather is chaotic.

On that Singapore website you'll see the SE winds already set in, as 'trade winds' along the N QLD coast. And along the N Aus coast from Darwin to Thursday Island. From June onwards, expect those SE winds to strengthen.

Note that that SG website does not use isobars in the style of weather charts in temperate areas. Atmospheric pressure differences in the tropics are not as meaningful as they are in NZ or AU. Surface wind streamlines or the sort of wind and wave maps served from that SG website are what count.

Let's say the boat owner has hired you to deliver the boat to BNE regardless of the weather.

Break the voyage into three or four legs: 1. from Langkawi S down the Malacca Strait to Singapore or thereabouts; 2. through Indonesia/the Maritime Continent to some convenient point; 3. entry into Aus waters; and 4. S down the QLD coast to BNE.

You can do the No. 1 leg in most any season: NE monsoon, Intermonsoon, or SW monsoon. Light winds are the rule, so motorsailing (or motoring) is common if you have a schedule. If you anchor each night, you might take a week. If you sail at night, keeping an eye on the fishing activity, you can do it in a few days depending on use of your engine.

But the No. 2 and No. 4 legs are going to be beats, and possibly challenging beats, from late June through to September or October.

I would not do the trip at the time you've indicated. Too much stress on the crew and the boat. Beating down the QLD coast against 30 knots of SE is a great way to see of what a boat and crew are made!

But let's continue assuming you are committed to the voyage at your indicated time.

For the No. 1 leg, I suppose you will take it easy as you learn the boat. And I'd suggest you keep in mind ports that have some repair services and marine supplies, given that this might be your first time on the boat.

So you might do sea trials around Langkawi and its islands, because you're positioned to take advantage of the marine supplies and services available there (and duty free entry of goods to Langkawi).

If you have an Android device with mobile broadband access in MY waters, you might want to download the free (as in beer) app MyCuaca (from the Google Play store; it's published by the Malaysian Met Dept; MY is the bigram for Malaysia and Cuaca of course means weather). Ignore the supposedly accurate weather forecasts. The tropics is too chaotic for accurate forecasting. MyCuaca's value is that it gives you easy access to weather radar (i.e. rain from t-storms and squalls) and satellite images (i.e. cloud cover).

I'd suggest a stepwise passage S along the MY coast something like:

a. Langkawi to Penang, perhaps with an overnight anchorage at Pulau Payar or Pulau Songsong, or an overnighter direct to Penang. You might find a mooring free at P Payar. P Songsong is coastal and you should be able to find an anchorage with protection from almost all directions. At Penang (P Pinang if you prefer) I'd suggest aiming for an anchorage at the 'Motorola anchorage' where you are protected from most directions by P Jerejak to your E and P Pinang itself to the west. If you need diesel fuel, Limbongan Batu Maung can sell to you. LMB also has (or had, I've not visited for a year or three) a Travelift, can make some repairs, and runs a small chandlery (Pen-Marine) in George Town.

b. Penang to Pangkor. You can find an anchorage somewhere in the Pangkor island group. The Pangkor Marina can provide repair services if needed. And is a potential temporary storage spot if your owner decides not to continue the voyage.

c. Pangkor to Port Dickson. Perhaps with an anchorage in the Port Klang area. The marina in PD similarly provides services and is yet another potential storage spot if your owner has come to her senses about bashing through legs No. 3 and No. 4. If you are continuing S, you could make PD your port of exit from MY (with your next port of entry being either Sinkers or Indonesia).

d. PD S towards Singapore. You do not have to enter Sinkers, but it's a convenient stop to get supplies, services, for crew changes, and to visit an Indonesian embassy for visas etc. From PD to Sinkers, you might find anchorage in the Water Islands off Malacca (my favourite used to be at P Besar, but P Dodol is fun too). You might aim for Raffles Marina in SG, for its chandlery and boatyard services. Of course, prices for supplies and services in SG are much closer to Aus & NZ levels than in MY.

e. SG to cross the shipping channels & traffic separation zone to perhaps Nongsa Point Marina to check into Indonesia.

As NZers, I guess you're familiar with Bob McDavitt. If you don't believe someone writing on CF with a surprised dog in the nuddy for an avatar, hire Bob as your weather router and ask him for routing advice and whether he'd advise May-June-July for your intended passage.
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Old 19-04-2017, 19:25   #7
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

Thanks to Alan and Matt for your advice. It will be taken on board.
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Old 20-04-2017, 08:29   #8
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

Carry as much fuel as you think you may need and double it. they dont call it motor SE Asia for nothing. You have left it late in the season but it is doable if you are prepared to wait for the weather. Langkawi to Pankor is best done at day light, plenty of good night anchor spots. From Pankor head for the edge of the shipping channels down the Malacca straight hug the east side as traffic is coming at you and the fishermen will be on your left, just shy of Singapore there is a couple of islands stop here for the night. Early morning it should still be dark, head towards Singapore, once the sun is up cross the shipping channel to the western side, hug the outside of the channel as now you are heading the same direction at the big ships. Head for Nongsa Point Marina, Batam Island, Indonesia. You don't need visas, but you should have completed on line, your yacht report for indo customs. The marina will do your check in and you can do you check out the next day, restock your beer at the ferry terminal by walking through the golf course and getting a taxi back. Having checked out of Indo you can only stop in an emergency or to get fuel, try for Lavina Beach, North Bali. Stay in the shipping channel and night time travel is pretty safe. Anchor with caution as the charts don't match the reef. dinghy to the spice beach resort and see the guy at the dive shop he will organize to have your fuel jugs collected and filled and returned. His mate is a fisherman with the boat called Marco Polo. Stay up in INDO as long as possible heading east before dropping down to GOVE, Australia, to check in. pick your weather for crossing the gulf and going over the top once you get to Port Douglas the rest is easy.
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Old 21-04-2017, 00:54   #9
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

Big thanks to everyone who has shared their thoughts with us. It is all great advice, that I am sure will help us immensely during this trip. Thanks for taking the time to respond. Being part of a community that looks after each other, is such a great thing.
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Old 13-06-2017, 00:10   #10
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

I am doing the same trip but leaving Langkawi september. Do you see much change in the weather patterns by then. I am considering laying the boat up in bali for a month or so once we get that far and come down to aus in october?
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Old 13-06-2017, 00:49   #11
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

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Originally Posted by Alan Mighty View Post
Bill99:

I guess you're familiar with the Asia-Australia monsoon system.


And I further guess you're aware that the southwest monsoon, the season of SW winds N of the Equator and SE winds S of the Equator, seems ahead of schedule this calendar year.


For the early spike in the SW monsoon, see: Monsoon Monitoring



.
Can you give some insight into how you interpret those monsoon index graphs?
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Old 13-06-2017, 19:07   #12
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

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Can you give some insight into how you interpret those monsoon index graphs?
Sure.

1. Each monsoon graph is a simple 2D chart.

The Y axis is the amplitude of the index, with the tick marks and absolute length of the determined by the long term historical record (or climatology) of that monsoon index.

The X axis is time, with tick marks at months (using the three letter abbreviations of the English language names of the months, so month 1 of the Gregorian calendar year is recorded as 'Jan' for 'January', month 2 is 'Feb', and so on).

Still with me?

2. Two curves on each chart.

One is coloured blue, with the legend 'Climatology'. That blue line is an attempt to show the hypothesised long term pattern in the data. It's a long term average, the length of the term being limited by the historical record of data. Call it 'climate' if you prefer.

The other curve is coloured red, with the legend '5-day running mean', and with circular data points. That's an attempt to capture the past twelve months of observations, with observations over a five day period averaged to one data point. Call it 'weather' if you prefer.

The red curve in any one monsoonal index chart fluctuates, sometimes in its own rhythm. Some of that rhythm is due to phenomena such as the Madden-Julian Oscillation.

3. Each monsoon index has been defined in the scientific literature.

If you follow the link for 'Definition' for each monsoon index, you will see a citation for the academic paper(s) that define each index.

Most or all of those academic papers are available freely on the internet after a search. See for example the paper by Bin Wang and Zhen Fan (from U of Hawai'i) at: http://journals.ametsoc.org/doi/abs/...M%3E2.0.CO%3B2

4. The divergence of the red curve (5-day running average or weather) from the blue curve (long term historical average or climate) tells you, as a cruiser, about the potential energy in the atmosphere at that point in time.

If, say, the red line at one point in time is at a higher index than the blue line, you might expect higher Convective Available Potential Energy (CAPE). Higher CAPE might suggest to you that you should prepare, compared to the usual climatological pattern, for more thunderstorms and squalls, higher wind velocity, and greater precipitation than usual. A red line and associated data points at a lower index level might suggest the opposite (lower CAPE, hence less rainfall, fewer squalls and thunderstorms, etc) to you.

5. The shape of the climatology line, the blue line, can be interpreted as the seasonal pattern.

Monsoon is just a distorted version of the Arabic word that I will represent in Latin letters as 'mausim'. The easy translation in English is 'season'.

For example, if you look at the chart of the Australian Monsoon Index, you will see a peak in the months Jan to Mar. That corresponds with what northern Australians call the 'wet season'. It's not necessarily a monolithic season; the indigenous inhabitants of northern Australia defined six or so seasons but the colonials who displaced them bunch two or more of those six into the 'Wet'. In N Aus, Apr - Mar is when N Aus people expect the peak of their cyclone (tropical revolving storms) genesis. And that blue line is also an indication (relevant to this thread) of wind direction. From Jun to Sep, sailors in N Aus would expect SE winds to prevail. From late Dec to late Mar, sailors in N Aus would expect NW winds.

For another example (and also relevant to this thread) look at the index charts for the Indian Summer Monsoon and the Western North Pacific. From Jun to Sep, sailors from Yemen to the E Coast of China have historically sailed to SW winds. Conversely, from late Dec to late Apr, sailors from E China to India and on to Yemen have expected NE winds. In between those two monsoons (or seasons) are two inter-monsoon seasons during which sailors have historically expected lighter and more variable winds.

So if you wanted to sail from N Aus (e.g. a port such as Darwin) to Singapore, you might aim to depart Darwin in Jul, when the SE is well developed.

6. Reading comprehension test.

So if you were in Langkawi, Malaysia, and wanted to sail to Bali, Indonesia, and then to Darwin, Australia, in what month would you choose to depart Langkawi? In your answer, discuss the effect of following winds on cruising comfort and also the risk of destructive squalls when near large land masses.
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Old 13-06-2017, 19:27   #13
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

Alan
Thanks for the writeup. You almost through me with colour but I figured it out��
The indexes are a ratio of U850 in one area minus another at a lower latitude. U850 is the winds at 850hPa????
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Old 13-06-2017, 20:15   #14
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

Done the voyage Darwin to Cairns a couple of times.


Both occasions I hung about in Darwin until October then wended my way across to Gove over a couple of weeks. It's actually a pretty good cruising ground.


The first time I stayed in Gove for five weeks waiting out strong easterlies and then crossed the Gulf in three days and was down to Port Douglas in a further eight. I pretty well sailed it all in light NW winds.


The second time I left Darwin about the same time and only needed to stay in Gove for about two weeks then motored across the Gulf and down to Cairns in calms or very light winds.
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Old 13-06-2017, 20:56   #15
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Re: Langkawi,Bali,Darwin,Cairns,Brisbane

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The indexes are a ratio of U850 in one area minus another at a lower latitude. U850 is the winds at 850hPa????
Hmm ... yes and no. It's wind shear at different altitude (vertical difference) for the Indian Summer Monsoon index, and wind shear at different altitudes at different latitudes (vertical difference over different locations) for the W N Pac Monsoon Index. The three indices are calculated differently but they are in harmony.

The simplest technique, looking at the vertical wind shear between 850 hPa and 200 hPa levels in one defined chunk of the N Hemisphere that covers the Indian sub-continent, is only relevant for the Indian Summer Monsoon Index.

I suggest you re-read Wang and Fan 1999.

Here's my attempt to answer your question.

1. Wang and Fan wrote their 1999 paper to resolve a contradiction: that the easy ways to calculate the Indian Summer Monsoon Index (either by looking at rainfall records on the Indian sub-continent [the All Indian Summer Rainfall Index, with data records dating back to the 19th century] or by looking at the vertical wind shear at 850 hPa and 200 hPa levels over a particular patch of the atmosphere above much of the Indian sub-continent) did not work when the same vertical wind shear was calculated for a larger area that extended from the Indian sub-continent to E Asia.

2. Wang and Fan resolved the contradiction by regarding the Australian-Asian monsoon system as having two lobes in the northern hemisphere, one lobe over the Indian sub-continent and another lobe over the Philippines.

They argued that in the Southeast Asian (aka Western N Pacific) lobe, wind shear is just not simply vertically arranged.

3. So the Western N Pac Monsoon Index is based not on vertical wind shear at one area but by vertical wind shear across two locations.

I think the message you should take away is that the three monsoon indices (Indian Summer, Western N Pac, and N Aus) are defined so the three indices are in harmony with data dating back to at least 1948.

Which makes sense, since they are parts of one big ocean-atmosphere coupled system that spreads from Aus to India, SE Asia, and E Asia.
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