Tuesday, 29 September 2015

All you need to know about glaciers, or maybe not

I could dedicate an entire  separate blog to rubbishing Guardian articles about the environment, climate change and the like. But for now, it amuses me to just pick the worst articles for this blog. Take today's article for instance, by one Wendell Tangborn. Who he? The Guardian has a mini résumé:
Wendell Tangborn has worked with glaciers for 55 years, beginning with South Cascade Glacier in Washington in 1960. Currently, his main interest is mass balance. He has developed a computer model that calculates a glacier's mass balance from routine weather observations and has published over 40 papers in glaciology. He lives on Vashon Island in Washington State.
He's "worked with glaciers"? I'll let that one pass, but it conjures up all sorts of strange images...
I don't doubt he's published over 40 papers in glaciology, but a Google Scholar search reveals that most of them concern the North and South Cascade Mountains that stretch from just over the Canadian border west of Vancouver (Canadian Cascades), through Washington and Oregon and into northern California. He is not an expert on glaciers worldwide, as the record of his published papers shows.
Glacier melt shows a climate change tipping point. We must pay attention 
Fossil fuel burning must taper off dramatically and be replaced with renewable sources of energy if we are going to survive as a species on this planet 
Mountain glaciers and humans have coexisted for roughly 200,000 years, but that long idyll appears to be ending. The earth’s 190,000 glaciers, sentinels of climate change that appear to be more sensitive to the climate than are humans, are disappearing at an unprecedented pace, the canaries in climate change’s coal mine.
There is evidence for many glaciers worldwide being in retreat, and there are estimates, but no one actually knows how many. Wendell's being rather less than truthful by implying here that all are in retreat. To cap it all, the "canary in the coal mine" appears here too. That coal mine must have hundreds of canaries in it by now, put there by many dozens of claims about climate, sea-level rise, coral reefs, glaciers - the list goes on and on. They can't all be "the canary in the coal mine".
It is all being driven by human activities, and it has been happening for three decades. The fate of both humans and glaciers will depend on drastically reducing carbon dioxide emissions during the next decade. 
Most of the world’s glaciers began changing in the late 1980s from relative stability to negative mass balances. Mass balance is the difference between growth from snow accumulation and shrinkage from snow and ice melting. The relatively abrupt change to negative glacier mass balances strongly suggests a climate tipping point, when the climate changes from one stable state to another.
Total rubbish - it's been happening at an increasing pace since the end of the "Little Ice Age" in the mid 19th. century. The World Glacier Inventory says that systematic glacier monitoring on a large scale began in 1894. The World Glacier Monitoring Service published a comprehensive report in 2008 titled "Global Glacier Changes: facts and figures" available here. On page 14 of the pdf is shown this figure:
     Fig. 5.9 The cumulative specific mass balance curves are shown for
     the mean of all glaciers and 30 ‘reference’ glaciers with (almost)
     continuous series since 1976. Source: Data from WGMS.

It should be obvious that "Most of the world’s glaciers began changing in the late 1980s from relative stability to negative mass balances." is baloney. There was no "relatively abrupt change" at all, hence no "climate tipping point". This is not science at all - it's politics. Perhaps it's true of some, or even all of the glaciers he's studied - the list isn't very long, judging by the abstracts of his papers, and certainly far, very far, from global.
There are other compelling signs that a climate tipping point has been reached. One of the most critical is the loss of the floating sea ice cover in the Arctic Ocean. In 2014, the late-summer extent of sea ice in the north polar seas was the lowest since satellite measurements began in 1979. Before 1979, evidence based on shipping and whaling charts suggests it has not been this low for at least hundreds of years. Paleo climatologists believe that Arctic sea ice cover last melted completely during summers about 125,000 years ago, during a warm period between ice ages.
More rubbish - in fact there is plenty of evidence pre-1979 that large parts of  the Arctic currently under ice were ice-free in late summer; newspaper articles and reports from ship's captains, whalers and explorers.
Reduction of northern-hemisphere sea ice means that more incoming sunlight is absorbed into darker ocean water instead of being reflected by ice and then re-radiated into the atmosphere as heat. This, in turn, reduces the extent of the annual northern-hemisphere snow cover, which further accelerates global warming. A related effect that could be even more environmentally devastating is the release of methane from permafrost and seafloor hydrates as the ocean warms. Another tipping-point indicator is the Greenland and West Antarctic ice sheets, which have shown signs of disintegrating during the past two decades. Just partial melting of these ice sheets will raise sea level several meters.
There is evidence that the warmer ocean water actually freezes quicker next winter precisely because it does radiate into the atmosphere, but not as heat, Wendell, but as long-wave infrared. He really knows his stuff, this Wendell.

He then says "Just partial melting of these ice sheets will raise sea level several meters". Depends just how much "partial" means, don't it? I've found out a little more about our Wendell - try this:
Tracking glaciers the Tangborn way 
Wendell Tangborn thinks he has invented a better mousetrap. He's still waiting for the scientific world to beat a path to his door. 
Sitting in a cramped home office overlooking the (rising) waters of Puget Sound, Tangborn talks about his plan to monitor 200 glaciers around the world to see whether or not — and, if so, how quickly — they're melting away. He has already done detailed reports on seven, including Juneau's incredible shrinking Mendenhall Glacier. He's working on 40 more, and hoping one or more foundations will supply enough money to hire the three people he'd need to keep track of all 200. 
People often cite the waxing or waning of glaciers to prove that the earth is or is not getting warmer. But according to Tangborn, no one is looking systematically at a large number of glaciers so that trends become obvious and the glaciers which are behaving contrary to the trends can be seen clearly as outliers.
What? "No one is looking systematically..."? The man's an ostrich with his head in the sand, or perhaps in a glacier crevasse. So in 2013 he'd reported on just seven glaciers out of his target 200. That target, using his own figure above of  190,000 would be just 0.1% of the total. Just how does he do it with his "better mousetrap"?
Basically, he uses temperature and precipitation data from fixed weather stations to calculate a glacier's "mass balance" — that is, the difference between the winter accumulation of snow and the summer melting of snow and ice. A positive balance means the glacier is growing; negative means it's shrinking. 
The program must be customized for every glacier. Tangborn must take account of the topography and total area of the glacier's surface. Once he plugs that into the program, he can sit in his office and get information that's as reliable as the data produced the old-fashioned way — the way he did it for many years — by climbing around on the ice with probing rods and shovels. 
For each glacier, Tangborn has to find a weather station that produces results in line with actual observations. That isn't necessarily the weather station right next door to the ice. Austrian scientists can't believe that Tangborn's using a weather station in Innsbruck to monitor the Vernagtferner glacier, which is 100 kilometers away, rather than a station close to the site. But, says Tangborn, somehow local weather phenomena keep the closer station from producing useful numbers.
This is clearly his "mass balance model", but he doesn't always use local weather data, but scratches around until he gets a fit with reality, or his reality at least. Innsbruck's elevation is 574m, the lowest point (the snout) of the Vernagtferner glacier is 2790m above sea level. He's using a weather station 100 km away, and more than 2000 metres lower, because "local weather phenomena keep the closer station from producing useful numbers". But it's the "local weather phenomena" which directly affect the glacier; no other weather phenomena can possibly affect it. Remember "He's still waiting for the scientific world to beat a path to his door.", and they haven't. I wonder why. Perhaps you can work it out for yourself.

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