The possible meltdown of reactors at Japan’s Fukushima nuclear power plant is a reminder of how desperately unsuitable nuclear power is as a response to climate change.

At time of writing, it’s still not clear what precisely has happened at Japan’s Fukushima nuclear plant, let alone what else is in store before the situation is brought under control.

The destruction of the main and the backup power supply for the cooling system by Friday’s earthquake and tsunami caused an explosion at the plant’s number 1 reactor. Some Japanese media reported that Japan’s Nuclear Industrial Safety Agency (NISA) had confirmed that this was a meltdown, contradicted by other Japanese government sources who said that the explosion only affected the outer shell and not the core of the reactor.

Either way, it’s not over yet. It now appears that the cooling systems have failed on at least one, if not two other reactors at the site. Thousands of people have had to have been evacuated from the 20km exclusion zone around Fukushima and 190 have been found to have been exposed to radiation. In addition, a state of emergency has also now been declared at a second power station at Onagawa. All in all, the conclusion that this nuclear accident was bad, but not as bad as Three Mile Island (a 4 on the 1-7 nuclear disaster scale, compared to 5 for Three Mile Island and 7 for Chernobyl) seems premature.

Japan’s nuclear industry has an unsavoury reputation on safety – in 2002, the president of the country’s largest power company had to resign on suspicion that the company had been forging nuclear plant safety records, and in 1999 a serious accident at the Tokaimura plant killed 2 technicians and injured 400 more. In this, it’s not unusual. Over its 55-year history, the global nuclear industry has now seen six major nuclear accidents and a long list of ‘minor’ safety breaches, like a worrying tendency to lose spent fuel rods.

In response to this, defenders of nuclear power will talk of improving the safety culture and cite new designs for nuclear reactors which supposedly make meltdowns a thing of the past. But we are entitled to be sceptical. Fukushima in fact indicates how the nuclear industry doesn’t seem to learn from its mistakes.

In a specifically Japanese context, despite a succession of incidents caused by earthquakes at Japanese reactors between 2005-2007, companies managed to ignore suggestions that perhaps their installations were not as prepared as they might be for a period of increased seismic activity. That the explosion in the number 1 reactor at Fukushima happened when both the cooling system and the backup failed is also important. This double failure was the same fault, although from a different cause, which caused the explosion at the US nuclear plant at Three Mile Island, 32 years ago.

Nuclear technology is not a safe technology suffering from some lax safety regimes. It’s a fundamentally dangerous technology which however ameliorated through improvements in reactor design will always pose a risk to large numbers of people if something goes wrong.

In the UK, the Con-Dems are planning 10 new nuclear reactors, with the argument that nuclear is a low carbon way of generating power. It’s an argument that defenders of nuclear power like to trot out, and one which you can only make if you ignore the greenhouse gas emissions which are caused by every stage in the nuclear power generation process, from mining the uranium to disposing of the nuclear waste, except for the actual nuclear reaction itself. But not only is nuclear power not green, Fukushima is a reminder of how desperately unsuitable it is as a response to climate change.

Japan’s catastrophic earthquake will not have been caused by climate change, but it is a reminder of how vulnerable nuclear installations are to natural disasters. Because of their water needs they’re often in coastal locations, and therefore particularly at risk from storm surges and sea level rises, all of which we can expect to see more and more of as climate change delivers an increasing likelihood of storms and floods. Nuclear power is not part of the solution to climate change; it’s part of the problem.