Sea Level Rise: A Major Non-existent Threat Exploited by Alarmists

by Dr. Tim Ball on June 8, 2011

in Atmosphere,Data,Land,Oceans,Theory

Samuel Johnson said,

Among the calamities of war may be jointly numbered the diminution of the love of truth, by the falsehoods which interest dictates and credulity encourages.

Climate change is a major battlefield in the US political war over the amount of government power and control. Diminution of the truth and exploitation of falsehoods are rife, and public credulity is exploited by general lack of understanding. A common comment after a presentation is, “I had my suspicions, but I didn’t know enough to know.” Generally, questioners are illogically thrown the precautionary principle that we should act anyway. Threat of rising sea level is a major weapon used to force unnecessary action for yet another non-existent problem.

For years I”ve asked, “What”s wrong with having global warming?” It”s a question that flummoxes people swamped by nothing but disaster predictions from the Intergovernmental Panel on Climate Change (IPCC) and mainstream media television that have hourly “Severe Weather” or “Extreme Weather” reports. After some thought, most people say their concern is sea level rise. What they don”t know is that, like CO2 induced warming, it is another falsely presented threat.

It is undoubtedly why Gore made it a significant part of his propaganda movie An Inconvenient Truth. It”s easy and dramatic to produce computer model simulations of low-lying areas inundated with water. It”s convenient that many are regions of high population density. A week before Gore received the Nobel Prize, a UK court ruled there were nine scientific errors and that some of these were done to enhance “the context of alarmism and exaggeration”. The Court wrote,

This is distinctly alarmist and part of Mr. Gore’s “wake up call”.

One of these was his claim of sea level rise of up to 20 feet “in the near future”. The ruling noted even if Greenland melted the water would be released, “but only after, and over millennia.” A second claim was low-lying inhabited Pacific islands are “being inundated because of anthropogenic global warming” and evacuations were occurring. The Court said there was no evidence of any evacuations. Gore exaggerates future levels well beyond his fellow Nobel Prize winners at the IPCC. And that is surprising, considering few of them know what they are doing. As world sea level expert and twice an IPCC member Nils-Axel Morner noted of the 2001 report,

First of all, it had 22 authors, but none of them – none – were sea-level specialists.

What Do We Know?

Despite exposure of Gore”s unjustified extremism, sea level rise continues as a major concern. But what are the facts? What do we know? The facts, as usual, show what is happening is perfectly normal with no evidence of a human influence.

Sea level is not level. This is a surprise to most people and enough to make claims of changing level questionable. For example, it is different at each end of the Panama Canal – yet the Pacific and Atlantic Oceans are connected at the both ends of the Americas. Sea level varies with changes in atmospheric pressure. It can rise up several meters over very large areas under large low-pressure systems. This is a factor in dramatic sea level rise when hurricanes approach land. It can vary with winds piling it up in one area and removing it in another. It varies with variations in crustal density. It varies with water temperature, expanding with warmer and shrinking with colder. This can result in a global or a regional change – or both.

But even this is not simple, because the water temperature varies with depth and different layers change temperature differently. So there are many causes of sea level change, and as one group of scientists explain, “a wide range of explanations for the current observed rise in sea level is possible.”

Global warming alarmists often exploit the determination of what is happening along a shoreline or on ocean islands. Shorelines change over time due to the water rising or falling (scientifically called eustasy), or the land rising or falling (called isostasy). It is difficult to separate one from the other in some locations, but in most it is clear. A classic example exploited by alarmists is along the Gulf of Mexico. Here the land is sinking as the continent adjusts to the removal of massive ice sheets, but it appears the sea is rising. At the other end of the continent the land is rising, as evidenced by the hundreds of shorelines around Hudson Bay.

History

Sea level has risen as the vast continental glaciers formed during the last ice age melted. It was some 150 meters (490 feet) lower 18,000 years ago and has risen since that time. The massive glaciers were built up by water evaporating from the oceans and accumulating as snow on the land that changed to ice. Melt began 18,000 years ago, but most occurred from 15,000 to 8000 years ago and sea level rose at an average rate of 14 mm a year. From 3000 to 100 years ago the rise was approximately 0.2 mm. Now sea level rise is directly and simplistically linked to melting glaciers and in turn linked to global warming.

Post-glacial sea level rise

Source: globalwarmingart.com

Originally a grossly simplistic theory asked how much would sea level rise if the Greenland and Antarctic ice sheets melt completely; the total water was then added to current sea level. The problem is, much of the ice is already in the ocean – so won”t add to the level. In addition, water expands by about 6% when it freezes, so the space occupied by ice below sea level will hold 6% more water. Similarly, ice above sea level will produce 6% less water by volume. Then there are the adjustments the land will make as the weight of the ice is removed. But all this is assumes total melt, and is unlikely for thousand of years (if at all) because the average temperatures of both Greenland and Antarctica are below –20°C (-4°F).

Temperature is the sole focus in the debate about changing size of a glacier but precipitation is equally important. Increased snowfall caused continental glaciers to grow but decreased snowfall can cause them to shrink. This is true of alpine glaciers and is the case with Kilimanjaro because area temperatures have not increased but lower precipitation has occurred. Counter-intuitively, in their detailed study Gravity and sea level, Sabbadini et al., note:

Increasing temperatures will lead to increased precipitation, which, in Antarctica will lead to an increase in mass stored on the sheet.

Unjustified Claims of Precision

The discussion is about the mean or average height of the sea. Traditionally, it was measured taking the average of tide gauge readings; since 1992, it is done by satellite. These satellites progressively include TOPEX/POSEIDON, Jason-1 and Jason –2. It’s important to note Jason-1 provides an estimate of sea level with an uncertainty of 3-4 mm. Both have a measurement accuracy of at least 3.3 cm. This is important because the IPCC claim, “For the period 1993 to 2003, the rate of sea level rise is estimated from observations with satellite altimetry as 3.1 ± 0.7 mm yr-1.” But what are they actually measuring? It is the average variation of sea level relative to an imaginary line called the reference ellipsoid. Potential for error exists in determining the ellipsoid, the height of the satellite, in the actual measurements, and in the changes going on in the ocean and on the land. Frankly, it is useless to even talk about millimeter changes. There are so many inputs and so many adjustments that the final results claimed are unjustified. Current estimates place sea level rise at 3 mm but as says,

It remains possible that the data base is insufficient to compute mean sea level trends with the accuracy necessary to discuss the impact of global warming – as disappointing as this conclusion may be.

He adds,

Useful estimation of the global averages is extremely difficult given the realities of space/time sampling and model approximations. Systematic errors are likely to dominate most estimates of global average change: published values and error bars should be used very cautiously.

Claims Don”t Fit the Reality

Everything was done by IPCC to attribute the increase to global warming, especially through increased sea temperature. They claimed that about 25 percent of sea level rise of the last 50 years was due to thermal expansion with that rising to 50 percent for the last decade. As with everything they do, the IPCC extrapolate their perceived trend forward, predicting increased sea level rise of 2 feet – far from Gore”s ridiculous 20 feet. It is also far from what other experts are saying.

Nils-Axel Morner is better qualified to speak about sea level than most (and certainly Al Gore). In an interview, Morner said,

If you go around the globe, you find no rise anywhere. But they need the rise, because if there is no rise, there is no death threat. They say there is nothing good to come from a sea-level rise, only problems, coastal problems.

Truth about sea level is a major casualty of the war to implement whatever is deemed necessary to implement legislation to increase government power and control.