Most people aren't able to pronounce it, but the eruption of Eyjafjallajökull in Iceland will long be remembered for the utter havoc it has wrought on air travel in Europe, with literally tens of thousands of flights cancelled, hundreds of thousands of people left stranded and countless millions of euro in revenue lost by the airlines.

GoldCore (which monitors gold prices) noted that "the economic ramifications of the Icelandic volcano for the already fragile euro-zone economy is being assessed, but it is safe to say that the severe disruption to travel which is affecting business travel, tourism, air freight and imports and exports in the euro zone will not help matters".

Not long after much of European air space was closed last Thursday, Paddy Power started taking bets on when it would be reopened. "Ironically, our odds are changing like the weather, and punters literally don't know whether they're coming or going," a spokeswoman said on Monday. "Mother Nature certainly has a twisted sense of humour!"

Perhaps without realising it, her jocose remark hit the nail on the head. Because what the volcanic eruption, and the cloud of ash it sent out, demonstrates pretty conclusively is how fragile and tenuous our construct is -- just as the tsunami in the Indian Ocean did on St Stephen's Day in 2004, destroying the Indonesian city of Banda Aceh.

"Nature will continue to make a mockery of our best-laid plans," wrote Prof Frank Convery, chairman of Comhar, the Government's sustainable development council. Yet, as he said, we engage in an "egotistical challenge" to nature by depleting the ozone layer, acidifying distant lakes, eliminating other species and warming up our planet.

As the dominant species, we believe that we can master nature with our sophisticated technology. But earthquakes, tsunamis and volcanoes are not susceptible to such mastery. What they show is that the environment is not a mere division of the economy, as many people seem to think, but that it's exactly the opposite.

Prof William Rees, of the University of British Columbia's school of community and regional planning, has noted that modern techno-industrial society sees "humans as somehow separate from the biophysical world, assumes we are masters of nature, and enables us to act as if society is not subject to serious ecological constraints".

Rees, who was joint author of an influential book, Our Ecological Footprint (1996), believes that this Cartesian perspective is "one of the root causes of humanity's prevailing unsustainable development path since it encourages the view that, through technology, the human system effectively floats free of any serious biophysical constraints".

All the hoopla about electric cars is another example of the same arrogance. The Government, egged on by its Green Party Ministers, has set a target that 10 per cent of Ireland's vehicles will be electrically powered by 2020, and is even offering €5,000 grants to encourage motorists to buy electric cars from the likes of Nissan and Renault.

The first four charging stations, or "juice points", have been installed in Dublin; by 2020, there could be 30,000 of them around the country.

According to Minister Eamon Ryan: "Ireland will be among the first in the world with this kind of nationwide infrastructure. It's bold, ambitious, and will show Ireland as a global leader in the green economy."

But has anyone apart from James Nix, transport policy co-ordinator for the Irish Environmental Network, asked where all the lithium needed for electric car batteries is going to come from? As he wrote recently in Village magazine, there is only enough lithium available to make five million of the 50 million cars produced worldwide each year.

"Although this shortage of lithium was denied at first, now even car manufacturers accept the problem, and Mitsubishi admits that lithium supplies are so tight that by 2015 electric cars may be uncompetitive to build," Nix said. Already, a lithium battery pack -- 100 times larger than what's in a laptop -- accounts for €7,000 of the cost of an electric car.

"Mining lithium is a dirty process. Vast amounts of chlorine are used . . . and [this] destroys the local water table. Industrial lithium production has already laid waste thousands of square kilometres, leaving water supplies too polluted even for agriculture, and ending farming in parts of Chile and Argentina. It threatens to do the same in Bolivia."

Most at risk is the Salar de Uyuni, a 10,000sq km salt plain, where Bolivia's left-wing government has recently approved a pilot project for the extraction of lithium. If this is expanded, the whole area could end up being destroyed -- a fate Nix compared to "churning up our Burren". But such will be the demand for lithium that this is almost inevitable.

Today happens to be Earth Day, for the 40th year in succession, and the planet is in more peril than ever. According to the US National Oceanic and Atmospheric Administration, the world's combined land and ocean surface temperatures made last month the warmest March on record.

Climate change sceptics and deniers, please note.

The fallout from Eyjafjallajökull may have a marginal effect in blocking sunlight from reaching the Earth; a volcanic eruption in Indonesia in 1816 that spewed 50 cubic km of ash into the atmosphere caused that year to become known as "the year without summer".

Certainly, blue skies over Europe have been remarkable in recent days because of the absence of jet trails for the first time in decades.