…According to maps prepared by the World Association of Nuclear Operators (WANO), around one in four of the world’s 460 working commercial nuclear reactors are situated on coastlines. Many were built only 10–20 meters (30–70 feet) above sea level at a time when climate change was barely considered a threat.
In the US, where nine nuclear plants are within 2 miles (3 kilometers) of the ocean and four reactors have been identified by Stanford academicsas vulnerable to storm surges and sea-level rise, flooding is common, says David Lochbaum, a former nuclear engineer and director of the nuclear safety project at the Union of Concerned Scientists (UCS).
Lochbaum says over 20 flooding incidents have been recorded at US nuclear plants since the early 1980s. “The most likely [cause of flooding] is the increasing frequency of extreme events,” he says.
“There was no consideration of climate change when most US plants were built,” says Natalie Kopytko, a University of Leeds researcher who has studied nuclear power plant adaptations to climate change. “They used conservative models of historical reference. Also, they were largely built at a calm period, when there were not many major storms.”
“While an accident has never yet happened due solely to sea-level rise and storms, the flooding experienced at Fukushima resembles what could occur in the future from sea-level rise,” says Kopytko.
Considering Climate Change
IAEA’s current global safety standards were published in 2011. These state that operators should only “take into account” the 18- to 59-centimeter (7- to 23-inch) sea-level rise projected by 2100 in the Intergovernmental Panel on Climate Change (IPCC)’s fourth assessment report, published in 2007.
But those safety standards don’t factor in the most recent assessment of the IPCC, published in 2013–14. This scientific consensus report has seas rising 26 centimeters (10 inches) to 1 meter (39 inches) by 2100, depending on how far temperature continue to rise and the speed at which the polar ice caps melt.
A 1-meter (39-inch) increase, combined with high tides and a storm surge, significantly increases the risk of coasts and nuclear stations being swamped, says Michael Mann, director of the Earth System Science Center at Pennsylvania State University.
“Nuclear stations are on the front line of climate change impacts both figuratively and quite literally,” Mann says. “We are likely profoundly underestimating climate change risk and damages in coastal areas…”