The scientific field is replete with honest differences of opinion. The oil companies find their scientists to discredit global climate warming, and some of them are quite qualified, if not respected. There are professors who are doomsdayish, and, in the eyes of their colleagues, perhaps exaggerate the truth to gain attention. Dedicated scientists absolutely detest those who prematurely publish or take liberties with the given facts. They are right, of course, and should continue to demand excellence and quality.
But take for example the line of reasoning asserting that most scientists support global climate warming as a problem because the review process is controlled and heavily skewed by those with this mentality. It would be like committing professional suicide to not be supportive.
Mind you, there are incidents that might have nothing to do with science itself. Geothermal R&D in Hawaii was stopped by Judge David Ezra in the 1970s, who sided with the Hawaiians, environmentalists and pot (marijuana) growers. Into the 1980’s, the Hawaii Geothermal Energy Project, after our initial success, limped along, finally to be terminated by Judge Ezra in 1991 for a lack of an appropriate environmental impact assessment. In 2007, he still is the Federal judge in Hawaii and geothermal development has virtually stopped.
The arguments of researchers providing sound facts and doing good science are regularly overridden these days by public officials influenced by noisy public opinion. Some want to protect the environment, others their homeland and, in the case of stem cell research, religious beliefs.
Ah, but mega tsunamis are something like global climate change, for there is considerable controversy. You can form three basic scientific points of view to a major landslide causing a tsunami: (1) no one has ever confirmed a true mega tsunami over 40 meters; yes, it is possible to have mega tsunamis, but mathematical models say the max wave height is 100 meters; and sure, there can be waves of 500 meters or more.
Group one is inconsequential, for what can be exhibited by unknown past events cannot preclude future occurrences. Thus, the real scientific debate is between groups 2 and 3. This means that, for the purposes of this analysis, it will be taken that the 10 meter normal far-field maximum of a major subsea earthquake generated tsunamis can, indeed, be surpassed by the 100 meter major event from a very large landslide from land or flank of an undersea formation. A 33 foot tsunami is frightening and formidable. A 330 foot tsunami is for the movies, but theoretically possible nevertheless, and in fact, exceeded in my lifetime by a factor of 5 in Lituya Bay, Alaska.
To further differentiate, the meaningful scientific debate for the purpose of this quest is not whether a 1600 foot (488 meter) tsunami is possible or not. That is not as controversial, as such, for several natural and unnatural causes can create such a wave in the near field. From an asteroid, say. Anyway, as a 100 meter tsunami is large enough, the critical question is whether the conditions at the so-called hot spots, Cubre Vieja, Canaries and Kilauea, Hawaii, for example, are capable of causing a sudden massive failure. Most scientists think not. The subsidence process, according to this faction, is continuous and gradual. No catastrophic flank collapses have been experienced in recorded history for both sites, they contend. In apparent contradiction, though, a paper in the Journal of Geophysics Research concludes that there was a past catastrophic landslide along the southeast submarine slope of Kilauea, which eventually led to present day stable slumping.
A particularly good example is the collapse on Oahu of Koolau Volcano a million years ago (give or take 500,000 years). Known as the Nuuanu Landslide or Nuuanu Debris Avalanche, where an apparent earthquake caused one third of the island to break off and fall into the sea. This might have been the largest landslide in the history of the planet, for just one chunk, known as the Tuscaloosa Seamount, is 20 miles (32 km) by 11 miles (18 km) and just more than one mile (1.8 km) high, and is located 60 miles (96 km) northeast of the Nuuanu Pali at a depth of 8800 feet (2680 m). As you drive towards Kaneohe/Kailua through the Pali or Wilson Tunnels and look back at the mountains, what you are viewing is that inside portion of the volcano that remained, although over the years, there has been considerable erosion and land build-up. A web page by Paul Jokiel of the Hawaii Institute of Marine Biology provides good info (Google search: “Jokiel’s illustrated scientific guide to Kaneohe Bay, Oahu”).
Kenji Satake of the Japan National Institute of Advanced Industrial Science and Technology reconstructed the event and surmised on the resultant tsunami from computer models using digital bathymetric data obtained on cruises commissioned by the Japan Marine Science and Technology Center. Estimated were: volume of 3000 km3 and velocity range from 20 m/s to 100 m/sec. Calculated tsunami heights were 100 meters (328 feet) in north Oahu, but 30 meters (98 feet) on the opposite side of the island, Waikiki. Five hours after the slide, 10-40 meters hit the Pacific Northwest and 30-70 meters in California, and in eight hours, 5-10 meters on the Japanese coast. Satake indicated that the wave heights could well have been double those sizes in the Hawaii Islands. So, a noted scientist did write about the prospects of a mega-tsunami in the far field from a landslide.
Thus that potentially largest earth fall producing a mega-tsunami a million years or so ago just happened to be from the island where I was born and still call home, Oahu. I live on Nuuanu Avenue, and the event was the Nuuanu Landslide. At our virtual antipode, the most recent possible major landslide occurred about 4,000 years ago on La Reunion Island, my choice as the possible home of the Free Hydrogen Economy, and one of my travel adventures provided in Chapter 6 of SIMPLE SOLUTIONS for Humanity. As the Canaries have been so thoroughly chastised as a potential source of the next mega-tsunami, and so has the southeast side of the Big Island, tomorrow we look at another hypothetical potential.