WASHINGTON — Since the 1997 international accord to fight global warming, climate change has worsened and accelerated - beyond some of the grimmest of warnings made back then.

As the world has talked for a dozen years about what to do next, new ship passages opened through the once frozen summer sea ice of the Arctic. In Greenland and Antarctica, ice sheets have lost trillions of tons of ice. Mountain glaciers in Europe, South America, Asia and Africa are shrinking faster than before.

And it's not just the frozen parts of the world that have felt the heat in the dozen years leading up to next month's climate summit in Copenhagen:

The world's oceans have risen by about an inch and a half.

Droughts and wildfires have turned more severe worldwide, from the U.S. West to Australia to the Sahel desert of North Africa.

Species now in trouble because of changing climate include, not just the lumbering polar bear which has become a symbol of global warming, but also fragile butterflies, colorful frogs and entire stands of North American pine forests.

Temperatures over the past 12 years are 0.4 degrees warmer than the dozen years leading up to 1997.

Even the gloomiest climate models back in the 1990s didn't forecast results quite this bad so fast.

"The latest science is telling us we are in more trouble than we thought," said Janos Pasztor, climate adviser to UN Secretary General Ban Ki-moon.

Since an agreement to reduce greenhouse gas pollution was signed in Kyoto, Japan, in December 1997, the level of carbon dioxide in the air has increased 6.5 percent. Officials from across the world will convene in Copenhagen next month to seek a follow-up pact.

The changes in the last 12 years that have the scientists most alarmed are happening in the Arctic with melting summer sea ice and around the world with the loss of key land-based ice masses. It's all happening far faster than predicted:

Back in 1997 "nobody in their wildest expectations," would have forecast the dramatic sudden loss of summer sea ice in the Arctic that started about five years ago, Weaver said. From 1993 to 1997, sea ice would shrink on average in the summer to about 2.7 million square miles. The average for the last five years is less than 2 million square miles. What's been lost is the size of Alaska.

Another new post-1997 impact of global warming has scientists very concerned. The oceans are becoming more acidic because more of the carbon dioxide in the air is being absorbed into the water. That causes acidification, an issue that didn't even merit a name until the past few years.

Acidic water harms coral, oysters and plankton and ultimately threatens the ocean food chain, biologists say.

In 1997, "there was no interest in plants and animals" and how they are hampered by climate change, said Stanford University biologist Terry Root. Now scientists are talking about which species can be saved from extinction and which are goners. The polar bear became the first species put on the federal list of threatened species, and the small rabbit-like American pika may be joining it.

More than 37 million acres of Canadian and U.S. pine forests have been damaged by beetles that don't die in warmer winters. In the U.S. West, the average number of acres burned per fire has more than doubled.

The Colorado River reservoirs, major water suppliers for the U.S. West, were nearly full in 1999, but by 2007 half the water was gone after the region endured the worst multiyear drought in 100 years of record-keeping.

"The message on the science is that we know a lot more than we did in 1997, and it's all negative," said Eileen Claussen, president of the Pew Center on Global Climate Change. "Things are much worse than the models predicted."