When the Fukushima Daiichi nuclear plant suffered a catastrophic breakdown in 2011 after being battered by a tsunami, a lot of Americans worried about radiation leaking from the plant and making its way across the Pacific into the waters off the North American coast.
Fukushima radiation did eventually show up off British Columbia the following year, according to a study published in 2014 in Proceedings of the National Academy of Sciences, and it's been continuing to drift this way ever since. Now, according to new research, an increased number of sites off the U.S. West Coast are showing signs of contamination from the crippled nuke plant.
That sampling includes the highest detected level to date, from waters about 1,600 miles west of San Francisco.
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But before you stop eating fish caught in the Pacific, it's important to keep things in perspective. Even that sample with relatively high radiation is about 500 times lower than the U.S. government's safety standard for radioactivity in drinking water.
The research was conducted by Ken Buesseler, a marine radiochemist with the Woods Hole Oceanographic Institution and director of its Center for Marine and Environmental Radioactivity, who plans to present his findings at the American Geophysical Union conference in San Francisco next week.
"These new data are important for two reasons," Buesseler, one of the first scientists to track Fukushima radiation, said in a press release. "First, despite the fact that the levels of contamination off our shores remain well below government-established safety limits for human health or to marine life, the changing values underscore the need to more closely monitor contamination levels across the Pacific."
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"Second, these long-lived radioisotopes will serve as markers for years to come for scientists studying ocean currents and mixing in coastal and offshore waters."
Buesseler, working with Japanese scientists, also continues to monitor the continuing leakage from the Fukushima plant, which includes collecting water samples from as close as a half mile away and sampling marine organisms, sediment and groundwater along the coast. The radiation levels there, while decreased, remain 10 to 100 times higher than those off the U.S. coast.
Tokyo Electric Power Co. is putting in place a frozen soil barrier in an effort to keep groundwater from flowing through the wrecked plant. The company also is building a seawall and drainage system to keep more contaminated water from reaching the ocean, Bloomberg News recently reported. Eventually, the entire facility must be dismantled and hauled away.
A 1999 photo of the Fukushima Daiichi nuclear power plant.
Although deadly, Hurricane Isaac scourged Louisiana with less ferocity than Hurricane Katrina did seven years ago. Katrina was one of American history's deadliest and costliest natural disasters. Part of what made Katrina such a tragedy was the inadequate emergency response from authorities. However, as intense as the outcry over the response to Katrina was, it pales in comparison to the repercussions of when one of history's deadliest storms struck what is now Bangladesh. Bangladesh was a part of Pakistan at that time, but the people of East Pakistan, as the region was called, suffered discrimination from the western portion of the nation and revolution was smoldering. The flames of nationalism and rebellion were fanned by the high winds of the massive Bhola cyclone which rushed in from the Bay of Bengal on November 10, 1970. The Pakistani government was criticized by locals and in the international media for failure to provide adequate disaster relief to East Pakistan, which may have contributed to the 300,000 to 500,000 people who perished in the storm and its aftermath. Soon after the cyclone, the storm of East Pakistan's outrage built into a war that tore Pakistan apart. The torment of war raged on until Bangladesh emerged as an independent nation from the flood of bloodshed that was the Bangladesh Liberation War. Throughout history massive storms have toppled human ambitions and left suffering and death in their wake. Particular natural disasters stand out from the line up of perpetrators as particularly devastating natural born killers.
The Day America Burned The wildfires that incinerated stretches of the American west this year were huge, but relatively few people lost their lives. On October 8, 1871 more people died in the flames of a wildfire than on any other day in recorded human history. On that day the Peshtigo Fire started in the forests of Wisconsin and was spread by a strong wind. The blaze quickly grew as it fed on trees left parched by a summer drought. The flames weren't extinguished until after they had snuffed out the lives of 1,200 – 2,500 people. The exact number is unknown because local records were also destroyed. The entire town of Peshtigo was consumed, leaving few to identify the charred corpses. On the same day, the Great Chicago Fire reduced much of the Windy City to ashes. Though Mrs. O'Leary's cow was later cleared of any culpability, the story of a kicking cow starting the fire became part of the legend surrounding the blaze that killed 300.
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Nature's Gas Chamber Other natural disasters can destroy whole towns at once too. Besides malaria, venomous snakes and leopards, the forest of Cameroon is also home to a lake that kills villages with its belches. Lake Nyos released an estimated 1.2 cubic kilometers (0.29 cu. mi.) of carbon dioxide and noxious sulfurous gases on August 21, 1986. As the bubble of heavier-than-air gas spread along the ground, approximately 1,700 people were suffocated along with 3,500 livestock. The killing cloud spread death up to 25 km (16 mi) from the lake. The lake's gas problem comes from an underwater magma dome that is constantly leaking carbon dioxide into the water. As the concentration builds, a disturbance in the lake's waters can cause the gas to be released in a suffocating explosion. Now, a degassing system siphon's the gas saturated deeper waters up to the surface, where the gas escapes in harmless quantities.
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4000 With One Bolt The Knights Hospitaller became the Knights of Rhodes after they lost control of Jerusalem to Muslim armies during the Crusades. They set up shop on the island of Rhodes in the 14th century by constructing a massive castle known as the Palace of the Grand Master of the Knights of Rhodes. The Knights also lost that stronghold to Muslim armies after the Turks conquered the islands and expelled not only the knights, but also the Greeks. Being expelled may have saved their lives. On April 3, 1856, a single bolt of lightning struck the steeple of the church attached to the palace. The Turks had been using the church and the storage area beneath the Palace as an ammo storehouse. When the fire found the gunpowder, an explosion leveled the 450 year old Palace and laid low 4,000 people. The Palace was rebuilt by the Italians in the early 20th century after they gained control of the island in 1912. The refurbished castle had the dubious distinction of hosting vacationing dictator Benito Mussolini after the Fascists rose in Italy.
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China Shattered by Quake Historical records in China extend unbroken for centuries. Included in those records are the body counts from some of the worst disasters in human history. An earthquake centered in Shaanxi province killed approximately 830,000 people on the morning of Jan. 23, 1556. In some areas, more than half the population was wiped out. One reason the toll was so high was that many residents lived in artificial caves dug into the soft soils of the area. The powdery soil collapsed in the quake, turning family homes into mass graves. Beneath those Shaanxi soils, the terracotta army of Qin Shi Huang, China's first emperor, may have been shaken from their slumber by the heaving of the earth around them and the misery of their country above them.
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China Drowned by Flood Floods have also terrorized the Chinese many times in the country's long history. Six of the ten deadliest floods in history struck the Middle Kingdom between 1887 and 1975. The worst may have been the flood of 1931. Estimates range as high as four million dead. The 1931 flood occurred after a two year drought ended. Heavy snows in the winter led into a rainy spring and even wetter summer during which seven typhoons drenched the land. The Yellow (Huang He), Yangtze (Chang Jiang) and Huai Rivers all flooded and inundated much of the country's cropland. Whole villages were washed away as dikes and levees failed.
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A Wave of Death Earthquakes and inundations can be deadly on their own, but together they pack a one-two punch of devastation. On Dec. 26, 2004, the third largest earthquake ever measured unleashed a wave that would wash away more lives than any other in history. More than 230,000 people died as the tsunami spread across the Indian Ocean from the quake's epicenter off the western coast of Sumatra, Indonesia. Fourteen countries were affected by the wave, especially Indonesia, Sri Lanka, India and Thailand.
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Ring of Fire For those countries that fall into the true ring of fire, the only man in black is the Grim Reaper, not Johnny Cash. The ring of fire is a line of volcanoes around the perimeter of the Pacific Ocean where tectonic forces make earthquakes and volcanoes an ever present threat. Indonesia shines like a jewel of molten magma set in the ring of fire. During the past 500 years, the area that is now Indonesia has suffered more deadly volcanic eruptions than any other place. An ancient eruption of an Indonesian volcano in the 400s AD may have darkened the skies over an already crumbling Roman Empire and led to crop failures. More recently, nearly 100,000 perished in the eruption of Mount Tambora in 1815. The eruption darkened the global sky and caused the Year Without a Summer, when chilly temperatures again led to failed crops in Europe. The island of Krakatoa exploded in a gigantic eruption in 1883 that ended 36,000 lives. Mount Kelut killed more than 5,000 in 1919. The same volcano had taken out 10,000 people in 1586.
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