Attempts to stem sea level rises by reducing CO2 levels in order to “combat” global warming are a complete waste of time says a new report by two of the world’s leading oceanographic scientists.
Over the last 150 years, average global sea levels have risen by around 1.8 mm per annum – a continuation of the melting of the ice sheets which began 17,000 years ago. Satellite measurements (which began in 1992) put the rate higher – at 3mm per year. But there is no evidence whatsoever to support the doomsday claims made by Al Gore in 2006 that sea levels will rise by 20 feet by the end of the century, nor even the more modest prediction by James Hansen that they will rise by 5 metres.
Such modest rises, argue oceanographer Willem P de Lange and marine geologist Bob Carter in their report for the Global Warming Policy Foundation, are far better dealt with by adaptation than by costly, ineffectual schemes to decarbonise the global economy.
No justification exists for continuing to base sea-level policy and coastal management regulation upon the outcomes of deterministic or semi-empirical sea-level modelling. Such modelling remains speculative rather than predictive. The practice of using a global rate of sea-level change to manage specific coastal locations worldwide is irrational and should be abandoned.
It is irrational not least because it is based on a complete misunderstanding of the causes and nature of sea-level rises. There are parts of the world where the sea level is rising, others where it is falling – and this is dependent as much on what the land is doing (tectonic change) as on what the sea is doing.
In other words – a point once made very effectively by Canute – it is absurdly egotistical of man to imagine that he has the power to control something as vast as the sea. The best he can hope to do is to adapt, as previous generations have done, either by deciding to shore up eroding coastal areas or abandon them and move further inland.
And for those still in doubt, here is what Vincent Courtillot, Emeritus professor of geophysics at Paris Diderot University has to say in his introduction to the report:
Sea level change is a naturally occurring process. Since the last glacial maximum, some 18,000 years ago, de-glaciation has taken place and this natural global warming has led to sea-level rise of on average 120 m or so. At some times, pulses of melt water coming from large peri-glacial lakes led to rates of sea level rise as high as 3 m per century. The rate slowed down some 7000 years ago and since then has been naturally fluctuating by only a few metres. The remaining global sea-level rise has been about 20 cm in the 20th century. Has this led to global disasters? The answer is no. If the projected rise over the 21st century is double what was seen in the 20th, is it likely that it will result in global disasters? Again, the answer is most likely no; human ingenuity, innovation and engineering, and the proper material and financial resources should solve local problems if and when they arrive, as they have in the 20th century.