A Reexamination of Climate Change Issues

Sea Level Issues (Book excerpts from “Unstoppable Global Warming — Every 1,500 Years”)


These excerpts from the book “Unstoppable Global Warming— Every 1,500 Years” explains the realities of sea level issues including why there is actually little danger of sea levels rising much during the next century, and why claims made in Al Gore’s movie “An Inconvenient Truth” predicting a potential sea level rise of 20 feet are wildly unrealistic.

Unstoppable Global Warming - Every 1,500 Years by Fred Singer and Dennis Avery.

“In the past 150 years, sea level has risen at a rate of 6 inches (plus or minus 4 inches) per century and is apparently not accelerating.  Sea level also rose in the 17th and 18th centuries, obviously due to natural causes, but not as much.  Sea level has been rising naturally for thousands of years (about 2 in. per century in the past 6,000 years).” — John Christy, Alabama State Climatologist, before the U.S. House Committee on Resources, 13 May 2003

WHAT SCIENTISTS PREDICT

The United Nations’ Intergovernmental Panel on Climate Change in 1990 predicted that man-made warming would produce a sea level rise of 30 to 100 centimeters (11.8 to 39.4 inches) by 2100. (307)  By 2001, the IPCC’s third assessment report had lowered its predicted sea level increase to between nine and 88 cm (3.5 to 34.6 inches). (308)  While the high estimate was still a potentially massive sea level rise, it revealed an even more massive uncertainty: A nearly ten-fold range of doubt.

The Summary for Policymakers of the IPCC’s fourth assessment report, Climate Change 2007, changed the prediction again, this time to a sea level rise of between 18 and 59 cm (7.1 to 23.2 inches) by 2100. (309)  Meanwhile, the U.S. Environmental Protection Agency (EPA) has published its own prediction that global sea level has a 50 percent chance of rising 45 cm (17.7 inches) by the year 2100 and a 1 percent chance of rising 110 cm (43.3 inches). (310)  Presenting the estimates along with the odds against them is a defensible position scientifically--but EPA knew the newspapers would report it as: “EPA says sea levels may rise as much as 3.5 feet, in line with the warnings of the Third Assessment report of the IPCC.”

So much for what government agencies say.  What do scientists report?  Scientists who specialize in sea levels believe there is no way to predict scientifically any sea level rise at all in the 21st century.  The IPCC has been harshly criticized for its handling of sea level issues by the International Union for Quaternary Research.  INQUA is a 75-year-old scientific organization dedicated to researching global environmental and climatic changes over the past 2 million years. (311)

INQUA’s Commission on Sea Level Changes and Costal Evolution says the IPCC has ignored the scientists who produced most of the data and observations of sea levels, choosing to rely instead on unverified model results.  The sea level scientists’ expert-based forecast of sea level rise is “10 cm—plus or minus 10 cm.”

Nils Axel Morner, the Swedish geologist who until recently was president of the Sea Level Commission, says sea level shows no trend at all over the past three hundred years, and satellite telemetry shows virtually no change in the past decade.  This is contrary to the model predictions of the IPCC.  “This implies that there is no fear of any massive future flooding as claimed in most global warming scenarios,” says Morner. (312)

Niels Reeh of the University of Denmark has reported a “broad consensus” among sea level experts that another 1 degree of warming would create only a tiny change in global sea levels.  He says the melting around the edges of Greenland’s ice sheet should increase sea level by only 0.3 to 0.77 mm per year.  Meanwhile, Antarctica would subtract 0.2 to 0.7 mm per year as increased precipitation added tonnage to its ice cap. (313)

The most likely rate of sea level rise in the 20th century is 10.16 to 15.24 cm (4 to 6 inches), the same rate of increase in recent centuries.  We have no reason to expect a bigger sea level rise in the next century, or the one after that, because global warming melt rates are being offset by increased humidity, snowfall, and ice deposition at the Poles.

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RISING SEA LEVELS - AL GORE’S UNLIKELY SCENARIO

In his unfortunately popular movie, “An Inconvenient Truth,” former U.S. Vice President Al Gore predicts a rise in sea level, not of the 4 to 6 inches endorsed by most experts, but of 20 feet!  Where could he have come up with such an absurd number?

Gore predicts another climatic event, similar to the Younger Dryas episode of 12,500 years ago, when the sudden release of of trillions of tons of melt-water from melting glaciers in North America shut down the Atlantic Conveyor, plunging the world into a 1,000-year ice age.  We can think of four reasons not to take this prediction seriously.

First, consider the trillions of tons of Ice Age ice sheets we don’t have because they melted more than 10,000 years ago.  Twelve thousand years ago, the Gulf Stream did get overwhelmed--by melt-water from the huge ice sheets and glaciers of the ice age as the planet warmed into the Climate Optimum.  But the ice age had created an ice sheet up to 9,000 feet thick over the northern part of Europe and North America.  The Laurentian Ice Sheet in the center of North America extended over all the Great Lakes, west into Iowa and south into Indiana and Ohio.  We calculate there were some 40,000 trillion tons of ice in the world’s various ice sheets and glaciers at that time.  Much of that ice is gone now, and the melt-water is already in the oceans.  Gore’s scenario cannot happen because there’s not enough ice to trigger it.

Second, the recent warming years, far from triggering a shutdown of the Atlantic Conveyor, have produced a rapid and systematic increase in the flow rate of deep Atlantic currents. (314)

Third, Dr. Gagosian of the Woods Hole Oceanographic Institute, one of the few scientists Gore is able to cite in support of his incredible thesis, is clearly engaged in the now-widespread scientific practice of “scaring up research funds.”  He noted in his statements that the seas are responsible for about half of the global climate factors, while virtually all of the global warming research money has gone to the atmospheric scientists.  (315)  His notorious alarming prediction was little more than a thinly veiled demand for more funding.

Fourth, computerized global circulation models say it won’t happen.  Computer modeling can be useful when the factors involved are known and the instructions to the computer can be based on real-world data.  After the publication of a report by the National Research Council’s Committee on Abrupt Climate Change, (316) researchers at the Lamont-Doherty Earth Observatory ran several versions of the Gulf Stream Collapse theory on the global climate model at the Goddard Institute for Space Studies.  The team found no evidence for a “tripping point” that would push the planet from the projected warming of the 21st century to an abrupt global cooling.  Instead, they found a linear response to glacial meltwater.  They say the expected increase in global melt water with the Modern Warming “is not rapid with realistic freshwater inputs.” (317)  In other words, without an extra 40,000 trillion tons of ice to melt, warming won’t shut down the Atlantic Conveyor--as it didn’t during the warming surges of 1850-1870 or 1920-1940.

The National Research Council report warns about “large abrupt climate changes” of “as much as 10 degrees C in 10 years,” stating that such changes “are not only possible but likely in the future.” (318)  The Rind team, however, found no evidence for this sort of dramatic “thresholds.” Rind says that in his team's model runs, the Atlantic Conveyor “decreases linearly with the volume of fresh water added through the St. Lawrence” and it does so “without any obvious threshold effects.” (319)

Nor did they find any evidence for a huge increase in fresh water inputs from the projected warming, despite its related increase in rainfall.  One reason, of course, is that snow can accumulate on ice sheets up to four times faster during the warm periods than during relatively cold periods. (320)  Anther reason is that ice melts slowly, deflecting much of the sun’s heat away form its core.  As a result, say the Rind researchers, the effect of warming on the North Atlantic’s deep water convection system “is not rapid.” (321)

Peili Wu and a team at the U.K.’s Hadley Centre for Climate Prediction and Research used the Hadley climate model to test the same hypothesis--that increased melt-water could shut down the ocean’s circulation.  (322)  It didn’t The Hadley model, in fact, found just the opposite: “accompanying the freshening trend, the [thermohaline circulation] unexpectedly shows an upward trend, rather than a downward trend.” The model thus agrees with the real-world trend.  The deep ocean currents are becoming more vigorous with the warming and its increased population.

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WHY SEA LEVELS WON’T RISE VERY MUCH

Global Warming alarmists assume a huge increase in sea level is inevitable and will occur soon if the planet continues to warm.  Sea level rise is a product of conflicting forces, however.

Warmer temperatures cause the volume of water to expand.  Warmer temperatures also melt glacier ice, creating more water.  But warmer temperatures also evaporate more water from oceans and lakes.  When clouds deposit the increased moisture from that rapid evaporation on polar ice caps and glaciers around the world, the ice caps and glaciers will grow, trapping more water, until or unless the local temperatures are warm enough to increase local melting.

Time is a critical factor.  Ice melts slowly.  Glaciers and ice caps can take thousands of years to melt completely because their surfaces reflect so much of the sun’s heat.  That is why the West Antarctic ice sheet, at least 10,000 years past its last Ice Age, still has another 7,000 years’ worth of ice to melt, according to John Stone of the University of Washington. (323)  Stone and his team analyzed the chemical composition of the rocks left behind on the mountains of Antarctica’s Ford Range when the ice began to retreat.

Given the Earth’s highly-variable climate history, another cooling period is almost certain to intervene long before the West Antarctic Ice Sheet disappears.  Moreover, the East Antarctic Ice Sheet, which holds the vast majority of the Antarctic ice, would still be massive.

D.C. “Bruce” Douglas of the Hurricane Center at Florida International University and W. Richard Peltier of the University of Toronto noted recently that today’s changes in sea level are tiny compared with those of past ice ages and warming periods.  Ancient corals found in Barbados reveal that sea level increased by about 120 meters (394 feet) since the last ice age began melting some 21,000 years ago.  By about 5,000 and 6,000 years ago, most of the ice age’s trillions of tons of extra ice had melted. (324)  After that, global sea level rise slowed, and apparently stabilized about 3,000 to 4,000 years ago.  No studies have detected and significant acceleration during the 20th century.

Walter Munk of the Scripps Institute of Oceanography reports that glacial melting due to higher 20th century temperatures can account for only 10.16 cm (4 inches) of sea level rise or fall per century.  Essentially, we do not know why sea levels in recent decades have sometimes risen at double that rate— but the average is six inches per century. (325)

The tectonically stable coastline of the Chukchi Sea in northwest Alaska shows sea levels there have risen only about a quarter of a millimeter per year over the past 6,000 years.  However, there have been several periods of both slower and more rapid increases. (326)

The world’s longest set of sea-level observations has been recorded for more than a thousand years at Stockholm, Sweden.  According to M. Ekman, they tell us that “sea level changes due to northern hemisphere climate variations since 800 A.D. have probably always kept within -1.5 and +1.5 mm/yr, with an average fairly close to zero.” (327)  This result comes about because land surfaces there are rising, offsetting the rise in ocean levels.  Scandinavia’s land is still rebounding as it adjusts to the removal of the heavy ice loads that covered it 12,000 years ago.

What about Venice?  The whole world knows that the priceless architectural treasures of the Italian canal city are threatened by rising water levels.  Venice is now flooded about 43 times a year, compared with seven floods per year a hundred years ago.  Doesn’t that prove the rising sea levels are a problem? 

The Italian National Research Council found the relative sea level in Venice rose 23 cm (9 inches) between 1897 and 1983, though recent measurements have shown this has slowed in recent years.  That’s the good news.

Unfortunately, about half of the apparent increase in water level was due to land subsidence in and around Venice.  Partly, this is due to the city’s buildings and bridges weighing heavily on the soft soils of the costal region.  Worse, part of it is also due to the underlying reality that Venice is on the African tectonic plate, which is gradually sliding under the neighboring European plate, and pulling Venice down at the rate of 2.5 cm (.98 inches) per century.  The city is now subsiding at the average long-term rate of 2 to 4 cm (.79 to 1.6 inches) per century, and that has virtually nothing to do with global warming. (328)

The city is erecting mobile barriers and internal water defense structures to minimize damage from high water levels during high tides.  They are the best ways we have today to adapt, not only or primarily to rising sea levels, but also to the apparently inevitable sinking of the Venetian land mass.


The book “Unstoppable Global Warming— Every 1,500 Years,” by Fred Singer and Dennis Avery may be purchased from Amazon.


















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