Tuesday, February 14, 2006


The biggest snowstorm of the season has belted north-eastern US, sinking New York City into its deepest snow on record, cutting power to thousands of homes, closing airports but bringing joy to ski resorts. "Make no mistake about it, this is a very dangerous, big storm," New York City Mayor Michael Bloomberg told a news conference. At least 68.3cm of snow fell in New York's Central Park, surpassing the city's previous record during a blizzard on December 26, 1947, which killed 77 people, according to the National Weather Service and city archives.

Authorities reported few fatalities as of yesterday evening (local time) because people heeded storm warnings and stayed inside. One man died when his truck slid off a Virginia highway and another was killed in a fire in Baltimore when snow hampered rescue teams. Whiteout conditions delayed flights and trains and shut airports in New York and New Jersey, the Federal Aviation Administration and the Amtrak rail service said, as the storm churned up the northeast coast from Virginia to Maine. Flakes of snow were reported as far south as Tennessee. "The snow is beautiful," said Gary Aichholz, manager of Magic Mountain, a ski resort in Londonderry, Vermont, which like other ski mountains across New England had suffered from unseasonably warm weather and scarce snowfall in January. "I think this will get people back in the spirit of winter and skiing," he said....

"It is quite a storm," said Brian Ciemnecki, a meteorologist at the National Weather Service's New York bureau, which began compiling records in 1869. "In some areas we're seeing snow fall at a rate of 10 inches (25 cm) in two hours."

As the storm wound down late yesterday, Hartford, Connecticut reported its heaviest snowfall since 1905 with 52.6cm. As much as 54.1cm had fallen in Columbia, Maryland, and 48.3cm in Birdsboro, Pennsylvania, according to Accuweather. Key roads and highways were mostly open and passable but still covered with snow....

Several airports were closed, including New York's John F. Kennedy and LaGuardia Airport, which shut for the first time in five years.

More here


Climate catastrophists have long said that global warming can cause drastic cooling in North Atlantic regions by "switching off" the Gulf Stream. And they say it happened once before. The rapid cooling in the prehistoric "Younger Dryas" period was said to be caused by a switching off of the Gulf stream. But the switching off is supposed to have be caused by a huge release of meltwater from the prehistoric Lake Agassiz. The research excerpted below by Lowell et al. reports evidence that no such release happened at that time


Meltwater drainage from glacial Lake Agassiz has been implicated for nearly 15 years as a trigger for thermohaline circulation changes producing the abrupt cold period known as the Younger Dryas. On the basis of initial field reconnaissance to the lake's proposed outlets, regional geomorphic mapping, and preliminary chronological data, an alternative hypothesis may be warranted. Should ongoing data collection continue to support preliminary results, it could be concluded that Lake Agassiz did not flood catastrophically into the Lake Superior basin preceding the Younger Dryas.

All preliminary findings imply a retreating ice sheet margin approximately 1000 years younger than previously thought, which would have blocked key meltwater corridors at the start of the Younger Dryas. If Lake Agassiz meltwater passing into the North Atlantic is not the trigger for the Younger Dryas, then perhaps there were different sources of water or triggers.

At this point, it seems prudent to carefully examine the role of glacial Lake Agassiz in any abrupt climate change scenario. The current paradigm for driving abrupt climate change is the modification of thermohaline circulation by the addition of external freshwater to the North Atlantic Ocean. Numerous modeling experiments have demonstrated the extreme sensitivity of this system, and attributing the source of that freshwater to glacial Lake Agassiz has evolved with numerous investigations. In the mid-1970s, Kennett and Shackleton [1975] noted that the isotopic composition of seawater in the Gulf of Mexico fl uctuated substantially during deglacial time, and they attributed the fluctuation to changing sources of meltwater from the Laurentide Ice Sheet. Approximately coeval with the isotope changes, the Laurentide Ice Sheet retreated northward into an isostatically depressed basin behind the subcontinental drainage divide. Researchers in the Great Lakes reconstructed lake-level history, and they recognized variations in meltwater routing either through the Mississippi River to the Gulf of Mexico or through the St. Lawrence River to the North Atlantic (Figure 1). By the late 1980s, Broecker et al. [1989] had honed the concept of a freshwater trigger upsetting thermohaline circulation, and modeling experiments defined the necessary meltwater fluxes.

The climate connection to glacial Lake Agassiz arose because organic sediments (10,960-9900 radiocarbon years [14C] B.P.) deposited between two sequences of deepwater clays would require a major drop in lake level, i.e. a meltwater releasing event coeval with the Younger Dryas. Subsequently,Teller and colleagues [e.g., Teller and Leverington, 2004] employed rebound models (delayed glacio-isostatic uplift of the Earth's crust from ice-sheet loading following deglaciation), lake-level histories, and ice-retreat patterns to calculate meltwater volumes reaching the North Atlantic via an eastern route.These calculations were compatible with modeling estimates needed to affect ocean circulation.Thus, a terrestrial meltwater drainage reconstruction for triggering the Younger Dryas existed that was compatible with ocean records.


Preliminary Findings

In the Fort McMurray area, three well-developed ice margins (Stony Mountain, Firebag, and Cree Lake Moraines) that spread over some 100 km are currently assigned radiocarbon ages of 10,030, 9595, and 9665 14C years B.P., respectively (Figure 3). Consequently, it appears that the plug was pulled and meltwater could have flowed through the Clearwater channel between 10,030 and 9700 14C years B.P., consistent with the maximum age of 9900 14C years B.P. for flood gravel north of Fort McMurray (Figure 3). Even with the earliest bracket imposed by the radiocarbon ages, deglaciation and meltwater routing may have been 1000 14C years later than the Younger Dryas.

This routing is more closely associated with the Preboreal Oscillation, a brief return to cooling after the Younger Dryas [Fisher et al., 2002], but precise temporal relationships have yet to be determined. In the Thunder Bay area, the current data indicate sequential deglaciation with the Shebandowan lowland submerged by a glacial lake until 10,200 14C years B.P., based on a combination of radiocarbon ages and varve counts on the inorganic, laminated lake clays below the radiocarbon sample level (Figure 2).

One interpretation is that sequential recession of the ice margin did not open an eastern outlet until well after the beginning of the Younger Dryas.An alternative interpretation has been that recession from a glacial re-advance associated with the Younger Dryas cooling is being dated, not the original deglaciation. At present, the data do not differentiate between a re-advance or not. However, the sample sites, some with glaciolacustrine sediments, plot above known elevations of Lake Agassiz and the subcontinental drainage divide.This implies a different rebound history or deglaciation pattern than has been proposed.

A central point for reconstructing the drainage of Lake Agassiz is the significance of the terrestrial macrofossils in fluvial sediment that indicate subaerial exposure between two formations of lake clay deep in the Agassiz basin.The oldest age on these deposits is 10,960 ñ 300 14C years B.P., indicating a lower water level at that time. However, reexamination of this date within the context of other numerous ages for this low lake level may indicate the wood was reworked into younger sediment, which would negate the temporal coincidence of the lowering lake level and the start of the Younger Dryas.

Thus, some key questions are: When and from what water plane did the drop occur? How fast was the drop? Where was the ice margin relative to the outlets? What was the basin volume at that time? All of these factors constrain any estimate of freshwater flux from Lake Agassiz into the oceans. Finally, if both outlets were blocked at this time, how extensive was the lake, and where was water draining at that time? Obviously, an understanding of the chronology of Lake Agassiz is incomplete at this time.


Preliminary results indicate that ice recession at both outlet areas is later than supposed, and that large volumes of meltwater were not catastrophically released from Lake Agassiz at the beginning of the Younger Dryas. Thus, if the Lake Agassiz floods did not upset the circulation pattern, the question becomes: What did? Could other pathways of the hydrological cycle alter the thermohaline circulation pattern at the beginning of the Younger Dryas, or alter other climate fluctuations that preceded Lake Agassiz? These investigations indicate that the geological understanding of past abrupt climate changes is only preliminary. This does not bode well for predicting future, abrupt climate changes.


Below is a letter to "Nature" from Eric Steig. Department of Earth and Space Sciences, University of Washington

Your News Feature "A sea change" (Nature 439, 256-260; 2006) states that evidence for the huge effects on climate of past thermohaline shutdowns is "near indisputable". You then claim that the best such evidence is the coincidence of thermohaline slowdown with the flooding of the North Atlantic following the collapse of Lake Agassiz, about 12,000 years ago at the beginning of the Younger Dryas cold period.

Yet Wallace Broecker, one of the chief proponents of the relationship between thermohaline circulation changes and climate, finds otherwise. In a recent study (T. V. Lowell et al. Eos 86, 365-373; 2005), Broecker and colleagues suggest that the case for the coincidence of these events is quite weak, and might well be wrong. Instead, they say, "preliminary findings imply a retreating ice sheet margin approximately 1000 years younger than previously thought, which would have blocked key meltwater corridors at the start of the Younger Dryas".

Of course, the proximal cause of a thermohaline "shutdown" (if such a thing can happen) is a separate issue from the influence of such a shutdown on climate. But it is highly relevant to this discussion of the sensitivity of the thermohaline circulation to current and future climate forcing.


A succinct email to Benny Peiser from Richard S. Lindzen (rlindzen@MIT.EDU), Alfred P. Sloan Professor of Atmospheric Sciences at MIT

The concern over the hockey stick has always struck me as weird. There are several reasons for my impression:

1. There is no doubt that Europe and the North Atlantic were warmer than they are today for several centuries during the high middle ages. This is more than enough information to tell us that major climate changes can occur without the present level of industrialization -- regardless of what happened to the global mean temperature.

2. Indeed, if the global mean temperature did not change while Europe and the North Atlantic underwent very substantial warming, this would imply a major change in the geographic pattern of temperature. However, a major assumption in the hockey stick is that the patterns remain fixed. One is then left with the paradoxical conclusion that if the hockey results are right, the hockey stick analysis is wrong.

3. The medieval warm period in Europe was a period of high population, vibrant intellectual activity, and an absence of famine and plague. The onset of the little ice age was marked by famine, plague, and much reduced population.

This suggests that warmth wasn't all that bad. At the same time, the Renaissance and the intellectual flowering that followed all occurred before the end of the little ice age, suggesting that human abilities can rise above the problems posed by the environment. In many ways, the whole story can be regarded as encouraging. Yet we focus on a couple of tenths of a degree in the global mean.


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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