ANTARCTIC ICE SHEET HAS BEEN GROWING SINCE 1992

(From CO2 Science Magazine, 8 November 2006)

Discussing: Wingham, D.J., Shepherd, A., Muir, A. and Marshall, G.J. 2006. Mass balance of the Antarctic ice sheet. Philosophical Transactions of the Royal Society A 364: 1627-1635.

What was done

The authors "analyzed 1.2 x 108 European remote sensing satellite altimeter echoes to determine the changes in volume of the Antarctic ice sheet from 1992 to 2003." This survey, in their words, "covers 85% of the East Antarctic ice sheet and 51% of the West Antarctic ice sheet," which together comprise "72% of the grounded ice sheet.""

What was learned

Wingham et al. report that "overall, the data, corrected for isostatic rebound, show the ice sheet growing at 5 ± 1 mm year^-1." To calculate the ice sheet's change in mass, however, "requires knowledge of the density at which the volume changes have occurred," and when the researchers' best estimates of regional differences in this parameter are used, they find that "72% of the Antarctic ice sheet is gaining 27 ± 29 Gt year^-1, a sink of ocean mass sufficient to lower [authors' italics] global sea levels by 0.08 mm year^-1." This net extraction of water from the global ocean, according to Wingham et al., occurs because "mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic mass loss from West Antarctica."

What it means

Contrary to all the horror stories one hears about global warming-induced mass wastage of the Antarctic ice sheet leading to rising sea levels that gobble up coastal lowlands worldwide, the most recent decade of pertinent real-world data suggest that forces leading to just the opposite effect are apparently prevailing, even in the face of what climate alarmists typically describe as the greatest warming of the world in the past two millennia or more.

Journal abstract follows:

The Antarctic contribution to sea-level rise has long been uncertain. While regional variability in ice dynamics has been revealed, a picture of mass changes throughout the continental ice sheet is lacking. Here, we use satellite radar altimetry to measure the elevation change of 72% of the grounded ice sheet during the period 1992–2003. Depending on the density of the snow giving rise to the observed elevation fluctuations, the ice sheet mass trend falls in the range ?5–+85Gtyr?1. We find that data from climate model reanalyses are not able to characterise the contemporary snowfall fluctuation with useful accuracy and our best estimate of the overall mass trend—growth of 27±29Gtyr?1—is based on an assessment of the expected snowfall variability. Mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic mass loss from West Antarctica. The result exacerbates the difficulty of explaining twentieth century sea-level rise.





Ocean Circulation: New evidence (Yes), slowdown (No)

Sometimes journalists are so focused on a particular story that they 'hear what they want to hear and disregard the rest'. There was a perfect example of this last week in the Guardian reporting from the RAPID Climate Change conference in Birmingham (UK) which I was attending. The conference, whose theme was observations, modelling and paleo-climate related to the Thermohaline and Meridional overturning circulation (MOC) in the North Atlantic, could have been expected to attract media attention (particularly in the Europe) and indeed it did. However, the Guardian story, which started "Scientists have uncovered more evidence for a dramatic weakening in the vast ocean current that gives Britain its relatively balmy climate" was in complete opposition to the actual evidence presented and I wasn't the only person to notice. How could the reporting be so wrong?

First, a bit of background: RAPID is a focused research program being run mainly out of the UK, but with contributions from Norway, the Netherlands and from the US. One of their main achievments has been to set up a mooring array (which consists of a dozen or so permanently attached monitors of temperature, salinity and pressure) that can continuously monitor the circulation in the North Atlantic across a section at 26øN. Measurements taken as the moorings were first installed were highlighted in the Bryden et al paper last year. As readers will no doubt recall, that publication, suggesting that a long term decrease in the MOC was underway, was greeted by a media storm. We cautioned at the time that the results were preliminary and, specifically, that the internal variability was probably high enough to make it unlikely that the changes had risen above the noise.

At the meeting this week, Bryden and colleagues gave an update of the work, specifically focusing on the first year of data from the moored array. This is the first time that there has ever been such a continuous set of estimates across the whole Atlantic and so reports of the size and nature of the variability were eagerly anticipated. And they did not disappoint! There were two key observations: first, that the approximations that had been used in the Bryden et al study were actually valid, and secondly, that the variations day by day varied by around 5 Sv (1 Sv is about 10 times the flow of the Amazon). The mean over the year for the MOC was 18 Sv - very close to what was expected and in the middle of recent estimates - and significantly, larger than the value seen in the 2004 snapshot. Given that degree of 'noise', this implies that no conclusions about trends over recent decades can be supported.

Other results presented supported this basic picture: transport estimates at different latitudes were not coherent with the initial results, model variability in the best ocean models was large (suggesting that detectability of a MOC slowdown before 2030-2050 was unlikely), and temperature, salinity and velocity changes in the overflow waters beteen Greenland and Europe showed significant connections to the North Atlantic Oscillation but no obvious trends. A number of records that had seemed to be trending strongly when first looked at, now seem to be simply more variable than first thought. This was something of a theme at the conference - the closer we look at the ocean, the more dynamic it appears.

So why was the Guardian story so wrong? Well, the nature of variability invariably implies that there are periods when the values are above the mean, and periods when it is below the mean. The minimum values appeared to be during a 10 day interval in November 2004 when the inferred deep western boundary current appeared to be very weak indeed. But then it came back. Now, recall that we have never seen this quality of data before and explanations for the variability (deep eddies? waves?) are not yet available. Thus, no-one has any clue whether this is normal or unusual - right now it's simply an interesting phenomenon. Picking this out of the results is therefore a little perverse. The big story should have been the phenomenal effort that has gone into exploring this important issue, the much improved context for previous measurements and a welcome reassessment of the significance of previous results. It's a shame the Guardian missed it.

Source





Stern report scare-mongering

Some skeptical comments from Australia:

Few government reports have been greeted with less scepticism than Nicholas Stern's scary scenario on climate change, but seldom has a report purporting to be a serious study been so deficient in scientific back-up. While its contents have been taken as gospel by various interest groups, the media and the ALP, a number of bona fide experts are deeply concerned at the report's lack of any real intellectual rigour.

Without gilding the lily, Dr Brian O'Brien, a strategic and environmental consultant, who was the foundation Director and Chairman of the WA Environmental Protection Authority, and previously Professor of Physics and Space Science in the US, has all the credentials necessary to make a reasoned, educated review of such a report. His verdict is damning. He says that not only are its forecasts out of whack with the last report of the Intergovernmental Panel on Climate Change (IPCC) of 2001, but also that if Stern wasn't so driven by political goals he should have waited until next year when the IPCC's fourth report is due to be published. "I think they're being quite naughty,'' he said. "All this apocalyptic talk when the situation is not so cataclysmic that they couldn't have waited till 2007 for the best available transparent data rather than rely on the coupling together of a five-year-old, out-of-date IPCC report, amended with references to a difficult-to-obtain German publication Avoiding Dangerous Climate Change, edited by H.J.Schellnhuber (Cambridge University Press), which is not only not readily available but was not subjected to the usual process of peer review.''

Professor O'Brien, who has a number of experiments still orbiting Earth aboard various satellites is currently assisting NASA recover data from the Apollo 11 program which the space agency "misplaced'' before coding, was clearly exasperated when he spoke with me from his Perth home. "There are a number of obvious problems with the report,'' he said, "not least being that Stern relies on the IPCC's 2001 report which estimated the maximum sea level rise forecast by 2100 would be somewhere between 9cm and 88cm and a leaked report of next year's IPCC report says the rise is possibly between 14cm and 43cm.''

Clearly, Stern has chosen to take the darkest possible view of the future. The professor said that in its initial report in 1995, the IPCC explicitly stated that its definition of climate change differed from that of the United Nations and Kyoto, because their definition included natural events plus human activities. "The first question, then, is what is climate change, if the scientific group advising the UN is thinking about natural phenomena as well as the scary stuff?'' he asked. "How about the so-called Federation drought which ran from 1895 to 1903, and the drought which ran from 1991 to '95, or the two in between, which had the most devastating effect in extent and on primary production, according to the Australian Bureau of Statistics Year Book for 2001?''

Professor O'Brien referred to remarks made by Robert White, the President of the US National Academy of Engineering to the annual general meeting of the US Academy of Science, in Washington, in April, 1989, where he said: "Whether we in the scientific community like it or not, we have awakened the political beast; we are confronted with an inverted pyramid of knowledge. "A huge and growing mass of proposals for policy action is balanced upon a handful of real facts.''

Professor O'Brien described a diagram of a big inverted pyramid, standing on a tiny little apex of a few facts such as increasing concentration of gases and a mass of assumptions rising on top of that, and exploding into all sorts of models and scenarios.

The Stern report, he said, is now at the peak of the apocalyptic drawing. He said the Stern report's sky-is-falling approach to climate change was exactly the same as the technique used at the first world conference on the changing atmosphere, and implications for global security held in Toronto in June, 1988. The opening quote at the conference, attended by more than 300 people from 46 nations was: "Humanity is conducting an unintended, uncontrolled, globally pervasive experiment whose ultimate consequences could be second only to a global nuclear war.''

This alarmist approach reeked of stupidity, snake oil, and misguided gospel preaching but was in line with a formula adopted by the first chairman of the IPCC, Sir John Houghton, who produced the IPCC's first three reports in 1990, 1995 and 2001 and wrote in his book Global Warming, The Complete Briefing, in 1994: "Unless we announce disasters no one will listen.''

Evoking the Great Depression and World War II may garner headlines for climate change but, without a factual basis, the Stern report is little but grandiose scare-mongering. It would be irresponsible in the extreme for politicians to make major policy changes - and major economic commitments - on such specious arguments.

Hollywoods Australian Idiot wannabees took to the streets of Sydney on Saturday Nov.4 demanding that "the government" do something to stop what was previously known as "Global Warming" they now call "climate change" thats the term they now use to cover their collective arses should it be hot or cold the day they are protesting, it just so happens the day they chose to march and share their collective wisdom among Sydney siders, it rained almost all day.

World famous scientist,climatologists actress /actor and member of the jugglers and clowns union, Cate Blanchett added her vast knowledge of science and meterology "Like the tens of thousands who marched today, I support clean energy and I vote.'' to the pool of chanting Green Peace, Green Left and International Socialist Movement activists who, using their best Henny Penny voices told us the sky is falling and we had all better pay more tax to stop it falling any further, apparently falling skies are very respectfull of World governments and Communist collectives and as such rarely fall on them.

Source






Australian PM backs closing wetlands for drinking water supply

Shock, horror for the Greenies. Doesn't the PM realize that "people are pollution"?

Prime Minister John Howard says he will support the closure of wetlands if it is necessary to secure drinking water during the drought. Yesterday's meeting of state and federal leaders decided to form an advisory group to consider contingency measures in case the drought continues next year. One option canvassed was to close wetlands to divert water to towns.

Mr Howard says people must always receive priority over the environment. "Quite honestly if we have to face the possibility of, for a temporary period, closing down a wetland in order to give people drinking water then I will support closing down a wetland," he said.

Greens Senator Rachel Siewert has attacked the suggestion. "The Prime Minister still doesn't get it, that you need a healthy environment to support people," she said. "And to hear him saying these things makes my mind boggle that he still doesn't get this." [We need swamps to keep us healthy??]

Source

***************************************

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

Comments? Email me here. My Home Pages are here or here or here. For times when blogger.com is playing up, there are mirrors of this site here and here.

*****************************************