21 October 2018 at 4:13 pm #7492imported_Martin WilliamsMember
Just seen this in an article in S China Morning Post, re the East Lantau Metropolis = Lantau Tomorrow Vision plan:
Charles Ng Wang-wai, chair professor of civil and environmental engineering at Hong Kong University of Science and Technology, said concerns about rising sea levels due to climate change were nothing short of “excessive” and “absurd”.
He pointed to data from the UN-backed Intergovernmental Panel on Climate Change, which indicated that Hong Kong sea levels would rise 0.6 metres by the middle of this century and surpass one metre by the end of the century.
“These are not major considerations in my opinion,” Ng said. “If a two-metre sea wall isn’t high enough, then you build one that’s four metres high. What’s the big deal?”
Prof Charles Ng seems unduly confident re sea level rise prediction by IPCC.
Compare in California; scientists saying should prepare for sea level rise of around 3 metres by 2100, and factor this into plans for infrastructure.
Also evidently clueless about storm surges, even after Mangkhut, along with waves on top driven by hurricane force winds – the kind of waves in Typhoon Jebi that flooded Osaka airport, which engineers had “guaranteed” against flooding by building defensive wall. Engineers’ hubris is no real match for power of nature, especially as climate change drives stronger storms; especially if only content to look at best case scenarios.
Note that IPCC may be underestimating sea level rise; various reports suggest ice is melting faster than expected. See, for instance:
Experts say the IPCC underestimated future sea level rise: A new study surveys 90 sea level rise experts, who say sea level rise this century will exceed IPCC projectionsProf Ng will be well aware of such reports; odd he seems to ignore them.29 October 2018 at 7:57 am #8979imported_Martin WilliamsMemberEmail just sent to a HK government engineer:I have lived by the sea almost all my life – in my home town of Scarborough, and since then on Cheung Chau, where my life is closer to the sea than for many HK city people.This helps make me keenly aware that sea walls should not only be a little higher than waves; but wind-driven waves, especially, can “explode” as they break against walls and other structures, with significant amounts of water going far higher.Further, of course, Hong Kong and the Pearl River delta are historically prone to storm surge.We had been fortunate since 1962, to not have a major typhoon with both a direct hit [or nearly so] along with storm surge.Until Mangkhut, that is: this was a storm that proved a wake up call for many in Hong Kong, but perhaps not engineers such as yourself, for some curious reason.Storm surges in Hong Kong can readily exceed 3 metres – as with Mangkhut in several places. Add tremendous waves with onshore winds, and these waves can be well over 5m above normal; and with startling power.– as seen with Mangkhut; yet with this, Hong Kong was fortunate as the storm lost some power over Luzon, did not hit directly, and hit a a time of low tide.Then, of course, sea level is rising, and this rise is set to accelerate. The IPCC tends to be on the conservative side, playing “catch up” as research shows climate change is more severe than many expected – making a rise of 1-2m or more very plausible by 2100, after which the sea will continue rising for centuries.Added to which, intense storms are forecast to be even stronger; a trend we are indeed seeing.– you surely know this.So it is puzzling to adopt a very mild typhoon impact as a model, and apparently cling to using this best case scenario.Perhaps naively, I had not expected this of engineers using science; as the Deng aphorism went, “seeking truth from facts”, even if contributing to a report that is little more than a glossy brochure.I also note re engineering “solutions” vs the power of nature: Kansai airport was “guaranteed” against flooding by typhoons, with its seawall increased to 5m or more above sea level; yet along came Typhoon Jebi, and it was flooded. Creating a place that could suffer such a fate seems, to me, irresponsible.I hope, too, you have seen recent news such as scientists recommending that California plan for 3 metres of sea level rise.https://www.scientificamerican.com/article/prepare-for-10-feet-of-sea-level-rise-california-commission-tells-coastal-cities/And from UK:“A new strategy to resist sea level rise is urgently needed as regular floods and erosion batter the English coast, according to government climate advisers.
Communities in vulnerable areas such as north Norfolk and south Devon have already seen these devastating events play out, with homes left inundated with water and cliff-top buildings sent crashing into the waves.
Experts have warned that this will only get worse as the effects of climate change play out across the country in coming decades, and many coastal areas will be left uninhabitable.”https://www.independent.co.uk/environment/england-floods-coastal-erosion-sea-level-rise-climate-change-a8601521.htmlSuch news may not be what senior government people in HK may want to hear, I know; but there we are: welcome to the new reality!
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