Friday, March 10, 2006

Antarctica: Long Term Policy, Short Term Data - A Poor Fit

Post lifted from The Commons blog

Today we were subjected to breathless news reports that - to quote the Washington Post's page one headline - the "Antarctic Ice Sheet Is Melting Rapidly: New Study Warns Of Rising Sea Levels". Its author, Juliet Eilperin, goes on to state that the ice sheet "is losing as much as 36 cubic miles of ice a year in a trend that scientists link to global warming, according to a new paper ..."

So what is this "trend" based upon? The trend, reported in a paper in yesterday's Sciencexpress [by Rignot and Kanagaratnam], which offers previews of coming attractions in Science magazine, is based on data collected over a 34-month period!

Sorry, Juliet, 34 months does not a "trend" make, unless you are 3-year old, in which case you can be forgiven for thinking that's a truly long time. like ... almost forever. Juliet, however, does go on to restore some balance to her story by quoting Richard Alley, "One person's trend is another person's fluctuation." Bravo!

Let's now look at the second part of the two-punch headline, namely, the warning regarding rising sea levels. It turns out that the resulting ice melt would raise sea level by 0.4 millimeters per year. Well, that works out to 1.6 inches per century. I guess I better hurry and relocate to higher ground - I have heard you can drown in a thimble-full of water (and I don't swim). That also means 1.3 feet in a 1,000 years. Seems I have to live longer than Methuselah to enjoy that beachfront property. Damn!

This is the second time in a month that there has been much ado about short term trends. In mid-February, another paper in Science reported that the glaciers in Greenland were melting more rapidly than previously thought [paper by Velicogna and Wahr]. That paper estimated that Greenland ice sheet was losing 224 cubic kilometers per year. That means it will take another 5,400 years to melt the remaining 1,200,000 cubic km, which might raise sea level by 23 feet (7 meters), or so I am told. That is a sea level rise of 0.05 inches per year.

Now this second paper was based on as much as 9-years worth of data. Phenomenal by comparison - but is this long enough?

To get an idea as to the answer, nearby I have two plots of temperature "anomalies' (i.e., fluctuations around the long term means) from 1880 through 2005 for the Antarctic (actually everything south of 60 degrees S). The top curve provides trends for land surface temperatures. The bottom curve is a composite for land and sea temperatures, hence the difference between the magnitude of the trend (0.12 degrees C per decade vs. 0.01 degrees C per decade).

What this shows is that you can get any kind of trend you want depending on when you start your 3- or 9-year period. Ditto, if you want to work with a 50- or 60-year period. In other words, beware long term policies based on short term data.

Nevertheless, the Washington Post reports that based partly on these studies, Sen. John F. Kerry (Mass.) and Rep. Henry A. Waxman (Calif.) said yesterday that the "United States must act quickly to impose mandatory limits on carbon dioxide and other greenhouse gases."

Perhaps, from the point of view of these two gentlemen, any "fluctuation" that lasts for 2 or 6 years is sufficiently long to base robust policy on.

Greenland and Antarctic Contributions to Sea Level Rise

Discussing: Zwally, H.J., Giovinetto, M.B., Li, J., Cornejo, H.G., Beckley, M.A., Brenner, A.C., Saba, J.L. and Yi, D. 2005. Mass changes of the Greenland and Antarctic ice sheets and shelves and contributions to sea-level rise: 1992-2002. Journal of Glaciology 51: 509-527.

What was done:

The authors determined changes in ice mass "from elevation changes derived from 10.5 years (Greenland) and 9 years (Antarctica) of satellite radar altimetry data from the European Remote-sensing Satellites ERS-1 and -2."

What was learned:

Zwally et al. report that "the Greenland ice sheet is thinning at the margins (-42 ? 2 Gt a-1 below the equilibrium-line altitude (ELA)) and growing inland (+53 ? 2 Gt a-1 above the ELA) with a small overall mass gain (+11 ? 3 Gt a-1; -0.03 mm a-1 SLE (sea-level equivalent))." Likewise, they say that "the ice sheet in West Antarctica (WA) is losing mass (-47 ? 4 Gt a-1) and the ice sheet in East Antarctica (EA) shows a small mass gain (+16 ? 11 Gt a-1) for a combined net change of -31 ? 12 Gt a-1 (+0.08 mm a-1 SLE)." Hence, they report that "the contribution of the three ice sheets to sea level is +0.05 ? 0.03 mm a-1." Furthermore, although not impacting sea level, they note that "the Antarctic ice shelves show corresponding mass changes of -95 ? 11 GT a-1 in WA and +142 ? 10 Gt a-1 in EA."

What it means:

We often hear horror stories about the potential for Greenland and Antarctica to add many meters to the level of the seas in response to global warming. However, Zwally et al. put things in proper perspective by noting that the real-world data they processed indicate that the ongoing contribution of the Greenland and Antarctic ice sheets to sea-level "is small relative to the potential contribution from ice sheets." How small? At the current sea-level-equivalent ice-loss rate of 0.05 millimeters per year, it would take a full millennium to raise global sea level by just 5 cm, and it would take fully 20,000 years to raise it a single meter. In addition, Zwally et al. report that "the contribution of the ice sheets is also small compared to the most recent estimate of current sea-level rise of 2.8 ± 0.4 mm a-1 from satellite altimetry (Leuliette et al., 2004)," which in their words, "further confounds possible explanations of the causes of contemporary sea-level rise."

In conclusion, the real-world findings of Zwally et al. suggest that the climate-alarmist hype about global warming causing sea levels to rapidly rise to dangerous heights due to the mass wasting of earth's great ice sheets is simply false. This outrageous claim is nothing more than a scare tactic designed to persuade the public to accept the bitter pill they prescribe for the solving of a patently obvious non-problem.


Below is the Abstract of the Zwally et al. article referred to above (Journal of Glaciology, Vol. 51, No. 175, 2005)

Mass changes of the Greenland and Antarctic ice sheets and shelves and contributions to sea-level rise: 1992-2002

Changes in ice mass are estimated from elevation changes derived from 10.5 years (Greenland) and 9 years (Antarctica) of satellite radar altimetry data from the European Remote-sensing Satellites ERS-1 and -2. For the first time, the dH/dt values are adjusted for changes in surface elevation resulting from temperature-driven variations in the rate of firn compaction. The Greenland ice sheet is thinning at the margins (-42~2Gt a-1 below the equilibrium-line altitude (ELA)) and growing inland (+53~2Gt a-1 above the ELA) with a small overall mass gain (+11~3Gt a-1; -0.03mma-1 SLE (sea-level equivalent)). The ice sheet inWest Antarctica (WA) is losing mass (-47~4Gt a-1) and the ice sheet in East Antarctica (EA) shows a small mass gain (+16~11 Gt a-1) for a combined net change of -31~12 Gt a-1 (+0.08mma-1 SLE). The contribution of the three ice sheets to sea level is +0.05~0.03mma-1. The Antarctic ice shelves show corresponding mass changes of -95~11 Gt a-1 in WA and +142~10 Gt a-1 in EA. Thinning at the margins of the Greenland ice sheet and growth at higher elevations is an expected response to increasing temperatures and precipitation in a warming climate. The marked thinnings in the Pine Island and Thwaites Glacier basins of WA and the Totten Glacier basin in EA are probably icedynamic responses to long-term climate change and perhaps past removal of their adjacent ice shelves. The ice growth in the southern Antarctic Peninsula and parts of EA may be due to increasing precipitation during the last century.


They sure know how to get people out of those evil cars

Branch lines across the West Country are to lose up to half their daily trains, despite rapid growth in passenger numbers over the past four years. The Government, which wants to reduce the rail network's 5 billion pound annual subsidy by at least œ1 billion, has authorised the biggest cuts to rural services since the Beeching report of 1963 after claiming that the lines are so poorly used that they are "in the last-chance saloon".

However, official figures obtained by The Times show that passenger numbers on the lines have increased by up to 40 per cent in the past four years, more than double the average rate of growth across the network. The figures are from Wessex Trains, the present operator, which has increased frequency at minimal extra cost since taking over in 2001. First Group, which takes over next month, has announced that services will be cut on all branch line in Devon and Cornwall.

Last week The Times disclosed that First was merely complying with the service levels set by the Department for Transport. Alistair Darling, the Transport Secretary, tried to blame First for making the cuts, but has now admitted that he approved service levels well below the present frequency.

On the Newquay branch in Cornwall, which will have only four trains a day from December instead of seven, passenger numbers have grown by 40 per cent since 2001. The St Ives branch will lose ten of its twenty-six daily services, despite attracting 25 per cent more passengers. The Looe Valley line, which recorded growth of 16 per cent, will have its services cut from thirteen to eight.

In Devon, the Tarka line from Exeter to Barnstaple will lose one service a day and most trains will no longer stop at several small stations. Wessex had upgraded them and installed new shelters, resulting in a 26 per cent increase in passengers.

Stuart Walker, Devon and Cornwall secretary of the Railfuture campaign group, said: "It is absurd to be cutting services on lines which are proving increasingly popular. Ministers keep saying they want more people to use public transport, but as soon as they do services are being cut." He said that it was deceitful of the Government to claim that the cuts were a commercial decision. "These cuts are the result of a reduction in public support for the railways," he said. "The Government could have stipulated that the existing frequency must be maintained, but it failed to do so. It's not just the branch lines but the main line too, where commuter trains which have standing room only are being withdrawn."

The 17.16 from Truro to Penzance, which carries 200 commuters, is being withdrawn, leaving a 100-minute gap in the timetable. Mr Walker said he feared that many commuters would switch back to cars. Tim Davies, head of transport co-ordination at Devon County Council, said that the Government had failed to inform rail users about its plans to withdraw support for rural services. "It's been done behind closed doors because the DfT wanted to get the highest possible premium payments from First," he said. First has agreed to pay the DfT 1 billion pounds over the next ten years for the right to operate the Greater Western franchise. Railfuture had hoped that First would use its profits on the lucrative London-Bristol main line to prop up rural services in Devon and Cornwall. However, the DfT is instead allowing First to cut services on the branch lines to fund the premium payments.



Red/Greens wanting to hurt the rich is what it is really about. Though if they got their way, it is the workers they would price out of air travel, not the rich. Article by Anatole Kaletsky

As I write this, I am flying back from a two-day trip to New York, as a result of which I am responsible for creating 1.2 tonnes of carbon dioxide. Next week I will be making two return flights to Europe, adding another 0.2 tonnes, and the week after that, I will be taking my entire family on a holiday to the Caribbean, creating roughly six tonnes of CO2.

Am I a carbon criminal for creating 7.4 tonnes of pollution, thereby bringing forward the day of judgment when we will all get our just deserts by roasting in a technological, post-enlightenment version of Dante's Inferno? Since none of my trips was strictly necessary for my survival, nor even for my ability to earn a decent living, I suspect that many readers will instinctively condemn me as a criminal, or at least a self-indulgent sinner. That certainly seems the gist of the moralistic debate in Britain about the contribution of air travel to climate change.

On the Today programme, for example, I recently heard the interviewer claiming, to a beleaguered representative of the Government or some pro-business lobby, that air travel was set to become the biggest single contributor to global warming. So why was the Government not taking some action to stop people flying? When it was pointed out that, according to the best estimates, air travel would create only 5 per cent of global carbon emissions by 2050, the interviewer seamlessly and quite unrepentantly changed his story: "Yes, but flying is the fastest growing cause of climate change" - a statistic that could only be true because aircraft emissions are increasing from such a low, almost infinitesimal, starting point, at present accounting for just 2 per cent of global CO2.

Why do I raise this issue? Because the debate on air travel suggests that many people in Britain, including most of the media and large parts of the political elite, still see the world through a Marxist prism: they still distrust economic incentives and market forces, preferring a benign, omniscient government to solve all social problems. Worst of all, they still feel instinctively that society is in a permanent state of class war.

Let's start with economics. Every serious study of aircraft pollution has concluded that the surest way of reducing emissions would be to bring airlines into the European regime for carbon trading. The idea is that airlines would be allocated an annual limit for carbon emissions, which they could trade among themselves. In order to expand beyond these limits, airlines would have buy "carbon credits" from earthbound industries such as power stations, steelmakers and motor manufacturers, who would then find ways of reducing their carbon emissions by an equivalent amount.

The merit of emissions trading is not just that it forces passengers to pay for pollution and airlines to become more efficient, since this would also be true of taxing airline fuel. The real advantage is that carbon trading allows airlines to pay for carbon reduction on the ground instead of in the air. And because there are many ways of reducing ground-based emissions readily available, every pound spent on ground-based carbon reductions is hundreds of times more effective than the same amount spent in the air.

To illustrate, let me return to my own globetrotting this month. The voluntary carbon reduction scheme introduced by British Airways on their website shows that a passenger who wants to offset the entire 1.2 tonnes of carbon created by a transatlantic round trip needs to spend only 9 pounds on planting new trees or subsidising an energy-efficiency programme in rural India. By contrast, an additional 9 pounds per ticket fuel tax would achieve absolutely no carbon reduction, since it would not be remotely sufficient to deter people from flying. As for promoting technological improvements in aircraft, a fuel tax would add nothing to the incentives that airlines already face. BA, for example, spends 1.4 billion pounds each year on fuel; so any technology that can save fuel is already worth adopting. This, indeed, is why airlines go on spending billions on new generations of aircraft and why jets replaced propellers decades ago.

Why, then, do environmentalists campaign for new airline taxes (which would be totally ineffective) or for outright bans on air travel (which will never happen), instead of arguing calmly for the economically rational solution of bringing airlines into a carbon-trading scheme?

Here we come back to the true political content of the flying debate. Opponents of flying are less interested in the practical prospects for reducing carbon emissions than they are in forcing politicians to "take a stand" against frivolous travel - ideally by banning it outright in the utopian visions of the authoritarian Greens. And behind the puritan contempt for travellers' self-indulgence lies an even deeper political agenda.

Airline travel is seen instinctively as a luxury, an indulgence of the prosperous classes. Denouncing air travel is therefore like sabotaging fox hunts, rioting against globalisation in the City of London or terrorising universities over "animal rights".

On closer inspection none of these single-issue protests has much to do with its putative objectives. Just as opponents of air travel are not really focused on the most effective way to reduce carbon emissions, the people who campaign against hunting or animal experiments are not really concerned about minimising animal suffering. If they were, they would be campaigning against meat-eating instead of pharmaceuticals, picketing abbatoirs instead of university labs and throwing blood at leather shoes and sheepskins instead of mink furs.

What, then, are these new protest movements really about? They seem primarily a way of expressing contempt for the rich and privileged, showing solidarity with the poor and downtrodden and creating an imaginary vanguard for a 21st-century version of Marxist class war. The end of communism and the rise of Tony Blair have left left-wing radicals with few options. So let them campaign for punitive taxes on air travel. Even if they succeeded, they would be less harm than old Labour's 98 per cent income tax


Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is to promote themselves as wiser and better than everyone else, truth regardless.

Global warming has taken the place of Communism as an absurdity that "liberals" will defend to the death regardless of the evidence showing its folly. Evidence never has mattered to real Leftists

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