I have sent these views on the Mekong debate, somewhat polemically worded, to some of the main players in this dispute. Underneath you will also find the response of one of them.
An Attempt to Pinpoint Flaws in the Debate about the Source of the Mekong
I may seem a touch arrogant of course. After all I’m new to the debate on the source of the Mekong. While all of you have been involved for years, and have actually been on expeditions near the river’s headwaters, and/or have meticulously catalogued the outcome of these expeditions.
I may also seem a touch too polemic. I am aware I’m living west of a great cultural divide, where this is generally accepted; while most of you reside east of it, where this may be considered too outspoken. I do not intend to offend anyone.
I think there are problems with the debate about the source on two different levels. First there are contradictions in published research data. These are obvious, and it should not be difficult to solve them. Second there is a problem on the level of the debate itself, that is…. there is no debate. This is a game where players make up their own rules. They can freely come up with their own criteria. Someone will say A (‘length’), another B (‘discharge’), a third adds C (the ‘Tao-theory’), then there is D (take glacier melting into account). It all gets politely catalogued. Nothing gets critically questioned, no-one will ask: wait a minute, does this make sense? Or: is this consistent? Those who set out on expeditions since 1994 did so in search of a scientific alternative to the known spiritual sources of the Mekong. If we refuse to put A, B, C, D to the test of reason, I am afraid we will end up with only more spiritual sources.
This is an attempt to test some of the arguments introduced over the years. But I’ll start with the first problem: contradictory research results.
Contradictions in research data Contradictions exist in the results of both remote sensing and field work.
As to satellite imaging – in 1999 the Gaodepu branch was measured to be longer than the Gaoshanxigu branch by Dr. Liu, while according to measurements by the Dexiang group the opposite was the case. Then the results of new measurements were published in 2007 by Liu, and subsequently checked by Martin Luzek of CERS. Both found the Gaodepu to be longer. It seems safe to say that the Gaodepu is indeed the longer branch: we can regard the 2007 figures as more reliable, due to improvements in remote sensing technology after 1999. (This argument is cited by Liu, in the October 2009 overview article by Mr. Kitamura in Japanese Alpine News.)
As to field research – contradictions here centre on the discharge of water at the Yeyongsongdou junction. In 1999 the Dexiang group measured a higher discharge for the Gaoshanxigu, but Liu found ‘no difference to take note of’. Then in his 2007 article Liu writes the Gaodepu is ‘the branch with the greatest flow of water’, without backing this up with actual numbers. On the other hand Mr. Wong observed, during his 2007 trip, the Gaoshanxigu to have a much larger flow. (Here too there are no numbers.) These contradictory claims about the water discharge at Yeyongsongdou are unsatisfactory.
Inconsistent and unconvincing arguments Most (all?) who since 1994 have set out in search of a scientific alternative to the spiritual sources of the Mekong, did so with the intention of looking for the longest tributary. Length of a river branch was either their sole criteria to pinpoint the source, or else it had priority. But subsequently many did not stick to this principle. They bent the rule, they came up with other criteria. I have come across three added arguments that I find inconsistent or unconvincing.
1. Water discharge Several have argued that water discharge must also be taken into account, when deciding which tributary will lead to the real source. Should we not remember that discharge was only officially allowed into the debate in 1999? At that point contradicting measurements about the lengths of Gaodepu and Gaoshanxigu made it impossible to appoint either Guozongmucha Shan or Jifu Shan as the Mekong source. Discharge was then accepted as a valid secondary criteria. But since 2007 there is no doubt anymore that Gaodepu is the longer of the two branches. So there is no case anymore for discharge as a decisive factor. Yet discharge lingers on in the debate as a factor to be taken into account. See e.g. Zhou Changjin, as quoted in the 2009 article of Mr. Kitamura. (Supporting discharge as a ‘decision-maker’ seems to me like telling an olympic long jumper: Well, you jumped furthest, but we will not award you your medal because we also take into account, say, speed at take off, or altitude gained, or amount of sand moved upon landing.)
2. Jifu Shan also drains water into the Yangtze This argument runs: Jifu Shan can not be recognized as the source of the Mekong, because it also drains water (more in fact) into the Yangtze basin. (E.g. Tao Baoxiang as quoted in Mr. Kitamura’s 2009 overview.) I do not understand this. We were tracing where the water in the Mekong comes from, and we ended up at Jifu Shan. Surely that is a valid source of the Mekong? Besides by extension this would mean that Jifu Shan can neither be regarded a valid source of a Yangtze tributary because it also drains water into the Mekong. Now what, hypothetically, if we were to find at some divide in this world a huge mountain and huge glacier that is the source of the world’s two longest rivers, flowing down at the two different sides of this divide? According to the ‘Tao-theory’ we would have to say that this glacier is not the source of these two rivers. Or else, if the point of the ‘Tao-theory’ is in the relative amount of water flowing down each side, we would have to recognize this glacier as the source of one of the rivers (that receives more water), but not of the other – even if that would be the head of by far the longest tributary of the world’s longest river. Who agrees? (Disqualifying Jifu Shan as Mekong source because it also drains into the Yangtze, is like telling the long jumper: Well, you won, but we will not give you your medal because you also take part in the 100 metre sprint.)
3. Current sources are glacier dependent, and therefore transient because these glaciers melt This stems from a new theory of CERS/Mr. Wong, announced in the most recent overview of the Mekong debate at the shangri-la-river-expeditions website. It has not yet been fully disclosed, and I am curious to know what it entails. For now, with regard to the retreating glaciers, I believe we can only pinpoint a source based on the current situation. We can’t be sure how the glaciers will change, and how fast. (Withholding ‘source-status’ to a place on the grounds that glaciers melt and situations change, would be like telling the long jumper: Well, you won, but we can’t be sure you will win again in four more years, so we do not award your medal.) Which isn’t to say we can’t speculate about the effects of melting glaciers: see appendix.
Opinion on the Mekong-source debate This is not a plea for length alone, as the factor that should decide about the location of the Mekong’s source. The long jump too is governed by more rules than just length. Records are only valid if the tailwind is less than 2 m/s. This makes perfect common sense, everybody will agree this is fair. Certainly people are most welcome to introduce new theories or criteria. But they should stand the test of reason and be ‘fair’. And in the three issues above I have hardly seen that. Those who in their search for a scientific alternative to the river’s spiritual sources come up with ideas and arguments that do not live up to this standard, are, I am afraid, at risk of creating their own spiritual source of the Mekong.
Appendix
Possible effects of glacier melting on the location of the source
I find this an interesting topic to speculate about.
First: note that there is a contradiction in numbers published about glacier surface area’s. In Mr. Kitamura’s 2009 overview the Guozongmucha glacier measures 0.67 km2. But in a 2001 contribution by Zhou Changjin and Guan Zhihua (in Geographical Research, translated by Mr. Nakamura, also on the shangri-la-river-expeditions website) this glacier has an area of 2.78 km2, and the glacier at Jifu Shan measures 0.60 km2. I can’t judge which is true, not yet having travelled beyond Zhaqen / Zhaqing myself.
If the Guozongmucha glacier has the larger area, it is likely also longer. That would mean it can retreat for a longer distance. So potentially Gaoshanxigu could then overtake Gaodepu as the longer branch. To do so, it has to make up 1.58 km (that is the difference in length between Gaodepu and Gaoshanxigu, according to the latest measurements of CERS). This scenario would mean that the real source of the Mekong would in the end be at the head of Gaoshanxigu. So pressing questions are: which is the larger glacier, and what is the difference in length between the two?
But what will happen once the glaciers melt completely? Maybe there will be no Gaoshanxigu and no Gaodepu left? The only water sources in the area will be rain, snow, hail. Where will that water start forming a stream? Will the source move closer to Yeyongsongdou, or even further down? What if there will be no precipitation for a while? The headwaters of the Mekong may temporarily or partly dry up?
Of course the time it will take for the glaciers to melt depends mostly on m3, not m2: mostly on volume, not on area. I have not found a publication with measurements or even estimates about the thickness of the glaciers at Jifu and Guozongmucha. Their thickness of course greatly influences their volume.
All these unanswered questions make it impossible to predict where the future source of the Mekong will be situated. The only thing we know for sure right now is that because of melting glaciers the situation will change. Could more research on the spot lead to a plausible hypothesis about the future location? Or will closely monitoring changes and developments be the only way to know where the great river starts?
Mr Winn's Comments
I much appreciated this instructive response of Mr. Winn of Shangri-La River Expeditions:
When Tomatsu first asked me to comment on Kita's first article, it was in the context of the Peissel publication of the source west of Moyun. Mr. Peissel had based his choice on 1:500,000 scale maps used by pilots, the only ones of this area that were available at the time (1994). Tomatsu wanted to know what criteria were used in other countries. Here is what I told him: “according to National Geographic and the US Geological Survey geographical conventions, the “true” source is the furthest one from the mouth. Ideally, it is also the biggest tributary and the highest in elevation, but these are not determining factors. If there are two sources equally distant from the mouth, the largest is the true source, and if both are equal in size, the highest is the source. Also by convention, the official geographical agency of the country within which the source is located is the final arbiter of disputes regarding the “true” source and is the repository for the survey data.” (From my journal of our 1999 expedition, http://www.shangri-la-river-expeditions.com/journals/mekong1999/zaqu99.html). I don't believe anyone has answered your question as to what is the potential length gain for each if (when?) the glaciers are fully melted. From Google Earth images, the similarity in elevations of the two glaciers and in elevations of the two springs suggests that the length of the two source tributary candidates are not likely to change enough to cause a change in sources, but I suspect How Man Wong will go to these glaciers and measure them on site. There are two agencies in China that are vying to be the official geographical agency that decides the source of the Mekong. In reality, they don't need to follow western conventions, which further complicates things. They may listen to foreigners, but they'll make their own decision, and who knows which agency will be the most persuasive.
Comment: It is new to me that there are in fact two competing refereeing bodies, instead of one. Still, their existence shouldn’t mean that contenders introduce new arguments and criteria without much solid reasoning, should it? Nor should it mean, I feel, that no-one seems to critically test the criteria and arguments of others.