The troubles of Fukushima nuclear-power plant - and other reactors - in northeast Japan have dealt a severe blow to the global nuclear industry, a powerful cartel of less than a dozen major state-owned or state-guided firms that have been trumpeting a nuclear-power renaissance.

But the risks that seaside reactors like Fukushima face from natural disasters are well known. Indeed, they became evident six years ago, when the Indian Ocean tsunami in December 2004 inundated India's second-largest nuclear complex, shutting down the Chennai (Madras) power station.

Many nuclear-power plants are located along coastlines, because they are highly water-intensive. Yet natural disasters like storms, hurricanes and tsunamis are becoming more common, owing to climate change, which will also cause a rise in ocean levels, making seaside reactors even more vulnerable.

For example, many nuclear-power plants along the British coast are just a few meters above sea level. In 1992, Hurricane Andrew caused significant damage to the Turkey Point nuclear-power plant on Biscayne Bay, Florida, but, fortunately, not to any critical systems.

All energy generators, including coal- and gas-fired plants, make major demands on water resources. But nuclear power requires even more. Light-water reactors (LWRs) like those at Fukushima, which use water as a primary coolant, produce most of the world's nuclear power. The huge quantities of local water that LWRs consume for their operations become hot-water outflows, which are pumped back into rivers, lakes, and oceans.

Because reactors located inland put serious strain on local freshwater resources - including greater damage to plant life and fish - water-stressed countries that are not landlocked try to find suitable seashore sites. But, whether located inland or on a coast, nuclear power is vulnerable to the likely effects of climate change.

As global warming brings about a rise in average temperatures and ocean levels, inland reactors will increasingly contribute to, and be affected by, water shortages. During the record-breaking 2003 heat wave in France, operations at 17 commercial nuclear reactors had to be scaled back or stopped because of rapidly rising temperatures in rivers and lakes. Spain's reactor at Santa Maria de Garona was shut for a week in July 2006 after high temperatures were recorded in the Ebro River.

Paradoxically, then, the very conditions that made it impossible for the nuclear industry to deliver full power in Europe in 2003 and 2006 created peak demand for electricity, owing to the increased use of air conditioning.

Indeed, during the 2003 heat wave, Electricite de France (EDF), which operates 58 reactors - the majority on ecologically sensitive rivers like the Loire - was compelled to buy power from neighboring countries on the European spot market. The state-owned EDF, which normally exports power, ended up paying 10 times the price of domestic power, incurring a financial cost of 300 million.