In France they are still counting the cost of nature and man-made errors

A year ago today, the worst storm ever recorded in France struck the Normandy coast and carved a swath of devastation 100 miles wide and 500 miles long.

A year ago today, the worst storm ever recorded in France struck the Normandy coast and carved a swath of devastation 100 miles wide and 500 miles long.

Trees that had lived for 200 years were snapped in half or pulled up by their roots as if they were weeds. Electricity lines were turned into spaghetti. Cars were blown off motorways or crushed by tree-trunks. Two-fifths of the trees in the Bois de Boulogne and Bois de Vincennes, the "green lungs" of Paris, were flattened.

The record set by the Boxing Day tempete did not last for long. Two days later, another storm, perhaps even stronger, with winds reaching 120mph in places, howled across the Bay of Biscay coast and wreaked similar havoc in south-western and central France.

Taking both storms together, 80 people were killed and 30 million trees were destroyed. Damage, to power-lines, railways, roads, forests and buildings, has been estimated at £3bn. Ten million were left without electricity; a million phone lines were cut.

A year later, the ferocity of the storms still puzzles, and disturbs, French meteorologists. What was startling about these winds was not just their initial ferocity - "at the limits of what is possible in Europe", according to the French Met Office, France-Meteo - but their tenacity and durability. Gales usually lose power once they strike land, but the storms of 1999 grew even more ferocious as they roared across France. The region most severely damaged by the first storm was Lorraine - 500 miles inland.

After a year of unusual weather in France and Europe as a whole - a cool summer followed by an interminably mild and damp autumn - it is tempting to blame the great storms of 1999 on global warming and the disruption of traditional weather patterns, but officials at France-Meteo are cautious. "One freak storm proves nothing," one said, "though it is true that last autumn was also unusually wet and mild. This partly explains why so many trees were lost. The ground in many places was exceptionally soft and damp."

The tenacity and reach of the storms is explained by another man-made interference with nature, or at least with traditional patterns of agriculture. France has more forest than at any time since the middle ages but the open ground between woodlands has been denuded of hedges, coppices and lines of trees to allow even greater yields of cereals.

Meteorologists believe that the first storm in particular failed to slow down because it blew out of Normandy into the great cereal-growing areas of central and eastern France before colliding with the forests of the Vosges.

One year on, the signs of devastation are still visible, as if an enraged angel had passed overhead, armed with a giant chainsaw. In state-owned forests, more than half the footpaths are still closed to the public because the trails are blocked or seen as dangerous.

The Bois de Vincennes and Bois de Boulogne in Paris, partly closed for many months, are open again, but barely recognisable in places. Nearly 6,000 young trees were planted in two bois this autumn but it will be half a century before the favourite strolling grounds of generations of Parisians become true woodlands again.

Just after the great storms, a number of experts wrote learned articles in French newspapers, suggesting that the culling of the woodlands was natural and could prove to be a good thing, if the fast-growing, alien, evergreen species planted in recent years were replaced with more native, broad-leaf varieties.

Taken over a century or half a century, this may be so. On a more human time-scale, the damage to the forests has turned out to be a catastrophe indeed. One of the worst afflicted areas was the hundreds of square miles of oak and pine forests along the Bay of Biscay coast west of Bordeaux. After 12 months, with no tree roots to soak up the water, some of this land is returning to the marshes from which it was recovered.