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New Software Could Warn Sailors of Rogue Waves
Reservoir Hill writes "Sailors have been telling stories for centuries about monstrous ocean waves that tower over a hundred feet in the air and toss ships around like corks. While these were once dismissed as nautical myth, but a few years back synthetic aperture radar from ESA's ERS satellites helped establish the existence of these 'rogue' waves and study their origins. Such waves were far more common than anyone had expected. Now a researcher in Madrid has developed software that can detect rogue waves from radar images, with the possibility of providing advance warning to ships at sea. The software uses a mathematical model to evaluate and process the spatial and temporal dimensions of waves inferred from the interaction between the radar's electromagnetic energy and the sea surface. The result is displayed in a color-coded image."
The subtext of this article is amazing. Basically, sailors have been out there getting killed by giant waves for decades, but a bunch of scientists decreed that such waves could not exist, and therefor, everything from safety standards, to engineering, to the ships themselves, were all designed in line with what was predicted, but not what was observed. During this entire time, numerous eye witness reports were ignored, and even the odd photograph was dismissed as a fluke.
I find it amazing that anyone would blindly trust an academic institution with any matter of policy, regarding climate, when, 2 ships a week have been sinking now for decades (on average), that, there's eyewitnesses that have said what caused these sinkings, and instead, ignored them. If there's a smoking gun that says that scientists find what they want to find, and its not necessarily the truth, then this is it, and the only way to save science is to demand that science must act scientific.
This is my sig.
There are no rogue waves, only Chuck Norris swimming laps.
Not necessarily.
Tsunamis and Rogue Waves are very different. If you'll forgive the generalisations; Tsunamis are mostly caused by events which result in the displacement of large quantities of water, such as earthquakes, landslides and asteroid impacts. They travel for hundreds, or even thousands of miles and cover a wide area of the sea. Their speed and height is heavily dependent upon the depth of the water - in deep water, they can travel at hundreds of miles per hour, but, crucially, may be no more than a few inches high. Ships can pass over them without ever realising they've done so. When they hit shallower water, the wave grows. However, what does the damage with tsunamis is not the height of the wave, per se, as the sheer amount of water behind it. The Boxing Day Tsumani that caused so much devastation a couple of years ago was only about 30 feet high when it hit land in many places - well within the range for a storm wave at the high end of the normal scale. However, the "wave" you see with a tsumani is just the front end of a huge body of water, with a vast amount of momentum. When a tsunami hits, it is as though the water level in the area affected has just jumped up to the height of the top of the incoming wave. This is obviously devastating, as it causes massive flooding and hugely powerful movements of water that can go miles inland.
Rogue waves, on the other hand, are essentially "surface" waves. The causes vary (winds running counter to currents is one cause, but there are others), but they have, in most respects, more in common with a storm wave than a tsunami. Their shape resembles that of a "breaking" wave when it hits the shore (although this is quite different from the "rolling" shape of a wave in the middle of the ocean) and there is no huge mass of water behind the wave itself. However, the height of a rogue wave is truly terrifying - essentially up to 100 feet - twice the size of the largest storm waves you could normally expect to encounter. Rogue waves are so dangerous to ships because their size and shape ensures that the pressure they exert on a ship they hit is way beyond what would normally be expected and designed for. However, they are rare and short-lived. The waves will usually be no more than a mile or two long and will run for about 10 miles or so on average.
The system discussed in TFA appears to be a radar based system. It works by picking up very, very large waves on radar and warning the crew of a ship caught in the path (giving them time to prepare and turn the ship to meet the wave). However, tsunamis would not show up on radar in mid-ocean and only the ultra-rare megatsunamis (which can occur either in an enclosed bay which suffers a massive land-slide, or on a broader scale when a truly massive asteroid impact or landslide occurs) would ever reach the height of a freak wave. Tsunami detection is likely better left to seismic monitoring and pressure sensors.