Researchers in France also found that the delicate balance of wildlife in different ecosystems is changing up to eight times more quickly than previously suspected, with potentially severe consequences for some species.

Rooting through a handful of mossy duff, Berg, an ecologist for the U.S. Fish and Wildlife Service, shows remains of shrubs and other plants taking hold over the last 30 years in a patch of ground that has long been too soggy for woody plants to grow.

The impact of global warming in the Arctic may differ from the predictions of computer models of the region, according to a pair of Penn State biologists. The team -- which includes Eric Post, a Penn State associate professor of biology, and Christian Pederson, a Penn State graduate student -- has shown that grazing animals will play a key role in reducing the anticipated expansion of shrub growth in the region, thus limiting their predicted and beneficial carbon-absorbing effect. The team's results will be published in the online Early Edition of the journal Proceedings of the National Academy of Sciences sometime between 18 and 22 August 2008.

British professor John Anthony Allan said the effect of the growing use of biofuels "is too frightening to even begin to realize."

Scientists plotted levels of thallium, cadmium and lead in a Greenland ice core and linked them to other chemicals indicating coal as the main origin.

The good news – for farmers at least – is that the irrigation water from sewers comes with free fertiliser in the form of the nitrates and phosphates bound up in human faeces. The bad news is that this coprological cornucopia is filling vegetables sold in city markets with heavy metals, pathogenic bacteria and worms.

Using the Quebec birth registry, the researchers analyzed data on nearly 100,000 live births registered between 1997 and 2001 in Montreal, Canada's second largest city where highways run through affluent and poor neighborhoods alike. The study is published in the Journal of Epidemiology and Community Health.

Stretches of Britain's coastline are doomed and plans will soon have to be drawn up to evacuate people from the most threatened areas, the new head of the Environment Agency warns today.

Senators McCain and Obama were each shown in front of film of the same giant wind farm, to lay claim to virtually identical "green" credentials. Since America has already built five times as many wind turbines as Britain, covering thousands of square miles, I checked out how much electricity all those 10,000 turbines actually produce. The answer is around 4.5 gigawatts - not much more than a single large coal-fired power station.

It would go far beyond previous expectations that remote and sparsely populated coastal areas would be beyond salvation, and mean that large swathes of towns and even cities could be swallowed up by the English Channel over the next century.

Worldwide, most glaciers are diminishing. So is the ice pack in places like the North Pole and Iceland. While ice loss is generally regarded as compelling evidence of global warming, most Americans aren't losing any sleep over it. An April Gallup Poll found that "while 61% of Americans say the effects of global warming have already begun," only 37 percent are worried about it, roughly the same percentage that were concerned when Gallup first began asking the same question, nineteen years ago.

… By the 1590s, Dunning notes, many parts of the world were experiencing a wave of starvations, rebellions and unrest. Then, he adds, “at this most excruciating moment, this other thing comes along to take things where they’d never gone before.” None of the countries of early modern Europe were equipped to deal with such crises, Dunning says.

Compared to prehistoric times, the level of oxygen in the earth's atmosphere has declined by over a third and in polluted cities the decline may be more than 50%. This change in the makeup of the air we breathe has potentially serious implications for our health. Indeed, it could ultimately threaten the survival of human life on earth, according to Roddy Newman, who is drafting a new book, The Oxygen Crisis.

Warmer springs and longer summers since the mid-1980s already have resulted in a fourfold increase in the number of wildfires and a sixfold increase in the amount of land burned compared with the period between 1970 and 1986, according to the National Wildlife Federation report.

U.N. talks on a new climate treaty to be agreed in Copenhagen at the end of 2009 resume in Ghana from August 21-27 -- overshadowed by worries about flagging growth and in an atmosphere soured by the collapse of world trade talks.