The Power of the Sea

Tsunamis, Storm Surges, Rogue Waves,

and Our Quest to Predict Disasters

 

Bruce Parker 


..... Images .....

The 1755 tsunami at Lisbon, Portugal.  The people ran from shaking buildings to the seemingly safe shore along the Tagus River, only to be struck by a 40-foot tsunami that had traveled up the river from the Atlantic Ocean, where the submarine earthquake had taken place.  It was followed by a second tsunami wave and a third.  But the tsunamis hit more than just Lisbon.  They traveled to northern Europe, to southern Europe and the northern coast of Africa, and crossed the Atlantic Ocean to the Caribbean (where the sea rose 20 feet at some islands), making this history's first contemporaneously recognized global natural disaster.  This event is described in the book in detail because of the many first-hand accounts in the historical record.  The data collected from many sources led to the first recognition (by  Rev. John Michell at Queen's College in Cambridge ) of tsunamis as very long water waves that could travel thousands of miles.  This etching is from the 1887 book by G. Hartwig, Volcanoes and Earthquakes.

 

The first twelve hours of the 2004 Indian Ocean tsunami.  The tsunami was caused by a 900-mile long submarine earthquake (indicated by the stars).  It was the first two hours that were most devastating.  Only 17 minutes after the earthquake, a 100-foot tsunami wave bulldozed towns out of existence along the Aceh coast of northern Sumatra, Indonesia.  In less than an hour 240,000 were dead.  In less than two hours smaller but still powerful tsunami waves had killed 7,500 in Thailand, 31,000 in Sir Lanka, and 16,000 in India.  Submarine ridges focused the tsunami wave energy like a lens focuses light, eventually guiding them out of the Indian Ocean and up the Atlantic, though now greatly reduced in size.   It was that same bathymetric effect that sometimes determined who would live and who would die.  More than 8,500 Sri Lankans died in Kalmunai at the shoreward end of a submarine ridge, while eight miles south only 2 died in Oluvil at the shoreward end of a submarine canyon.  This is a modified version of a model-produced map from NOAA’s National Geophysical Data Center.

 

 

Destruction along the coast of Aceh in northern Sumatra, Indonesia, caused by the December 26, 2004 tsuami.  At some locations mosques were the only man-made objects to survice, because the water could flow through the open first floor.  Using numerous first-hand accounts and scientific studies, the book describes the 2004 tsunami from the moment the submarine earthquake occurred through its first 24 hours, mixing the tragic events with the scientific explanations of what was occurring.  (Picture from the U.S. Geological Survey)

 

 

Destruction due to the storm surge produced by a gale along the coast of North Friesland, Germany, in 1634.   Over the centuries storm surges have killed many times more people than tsunamis.  This etching, called "Die erschreckliche Wasser-Fluth" ("the terrible flood waters"), is taken from Eberhard Happel's "Greatest Curiosities of the World," published in 1683.  Tens of thousands died along this coast and the coast of Holland, one of many such storm surge tragedies to occur in this region.  Yet this pales in comparison to the millions that have died from storm surges (produced by tropical  cyclones) along the coasts of the Bay of Bengal -- in India, Bangladesh, and Burma.

 

Some of the destruction from the 1900 Galveston storm surge.   The greatest death toll from a natural disaster in the United Staes was due to the storm surge (caused by a hurricane) that overwhelmed the coastal city of Galveston, Texas, on September 8, 1900.   At least 6,000 bodies were found, but the death toll was probably over 8,000 based on missing people, many of whom were probably washed out to sea. This picture shows only some of the destruction, an area where hundreds of homes stood prior to the storm surge. (Picture from the National Oceanic and Atmospheric Administration photo library.)

 

East India Company’s iron war steamer Nemesis among huges waves in the Agulhas Current off the Cape of Good Hope, South Africa.  This is the area of the world most notorious for rogue waves.  Large waves are generated due to the unlimited fetch around Antartica, and when these waves run into the opposing strong water flow of the Agulhas Current, energy from that current is transferred into the waves, making them even larger.  Focusing effects and random combinations occasionally produce monster rogue waves that are two or three times the height of any of the waves around them.  The result is calamitous for even the largest ships.  (This is an 1841 Reeve engraving of a Leatham painting.  From the Mariners Weather Log.)

 

The splitting in half and sinking of the supertanker World Glory in 1968 off South Africa after being hit by a rogue wave.  A wave at least 70 feet high split in half this 737-foot long supertanker, releasing 334,000 barrels of crude oil.  (South African Sailing Directions)

 

 

 

A 1543 Brouscan tide almanac.  The tides were the first ocean phenomena to be predicted (if only crudely) because as far back as ancient times it was recognized that there was a correlation between the rising and the falling of the sea and the movement and changing phases of the moon.  Although it was not until 1687 that Sir Isaac Newton first explained how the moon and the sun caused the tide, there were for centuries various approximate techniques by which mariners predicted the tide.  This 1543 Brouscon tide chart was carried by sailors so they would know when the tide was high enough for ships to enter a particular harbor without running aground (and possibly sinking from the damage done to the ship's hull by the sea bottom).  (From Digital Scriptorium at the Bancroft Library at U. Cal Berkeley, originally from the Henry E. Huntington Library and Art Gallery.)

 

   

 

Napoleon’s escape from the Red Sea on December 28, 1798.   At low tide Napoleon and his men were trying to cross the northern end of the Gulf of Suez (at the northern end of the Red Sea), because the receded water revealed a dry bottom on which they could ride.  But they began crossing too late, and when the tide waters returned violently and swirled around them, they were almost overcome.  It was luckily a neap tide (the moon pictured in this etching was correct).  Had it been a spring tide (at full or new moon), Napoleon's career might have ended that day.   After his ordeal, Napoleon saw a connection between his experience and that of the Pharoah about 3,000 year earlier, which is explored in detail in the book.  (Etching from Harpers New Monthly Magazine, 1852.)

 

 

 

The U.S. Coast and Geodetic Survey tide-predicting machine No. 2.     Based on the work of Newton and Laplace, Lord Kelvin (and in the U.S., William Ferrel) built finely crafted brass tide prediction machines consisting of dozens of pulleys and gears.   The tide prediction machine in this picture was completed in 1910 and handled up to 37 tidal constituents.  It was used during World War II to make the tide predictions for amphibious landings in North Africa and the Pacific. (Picture from U.S. Coast and Geodetic Survey, 1915.

 

  

General Field Marshall Rommel at low tide next to the beaches of Normanyd just before D-Day.   Rommel was inspecting some of the many thousands of underwater obstacles he had built between the low-water line and the high-water line.  These were designed to rip out the bottoms of Allied landing boats if they landed at hight tide.  Normally, the Allies would have preferred to land near high tide to decrease the sandy beach they would have to cross under German fire.  But because of the obstacles the Allies came at low tide, so demolition engineers could try to blow up them up.  Tide predictions were critical to the planning for Operation Overlord and for the selection of the date of D-Day. (Picture from the Dwigth D. Eisenhower Library.)