The starting premise of Dr. George Woodwell’s presentation at Grace Church on Monday was bland enough. For civilization to thrive, he said, it requires both a political system and an economic system that work.

But from there, it got very scary, very fast. For, he continued, those systems were on the verge of breaking down — in some places had already broken down — because the world’s environment, on which they ultimately depend, was fast breaking down.

Dr. Woodwell, the founder of the Woods Hole Research Center and an ecologist who has spent most of his working life studying global environmental issues and climate change, said the world now had reached the point where the quality of life of people everywhere was being “systematically undermined.”

Take the example of Haiti. Most Americans, when they think of that country, think of last year’s devastating earthquake.

But that was just the most recent misery. Long before the earth shook, he said Haiti was in an “environmental abyss” of human making.

The forests were all cut down, meaning when it rained, the water simply ran off, taking the topsoil with it, devastating both agriculture and fishing.

As a result, he said, “There is no basis for supporting an economy, and no basis for supporting a government, and there hasn’t been one for decades.”

As a further result, there was a Haitian diaspora, people moving in particular to Brazil, which had its own dire environmental problems.

Or look at the mass migration of people within, and out of Africa, where persistent drought has caused famine. Look at the “enormous pressure” this was putting on the southern frontier of Europe

Look at the record heat in Europe in the summer of 2003, which killed tens of thousands of people, the increasing frequency of fires in the boreal forests of the northern hemisphere, one of which buried Moscow for weeks in smoke last summer.

Consider the borers which had been killing vast numbers of trees in Alaska over the past decade or so. Or the two-year drought now afflicting the southern United States, even as there were floods in the higher latitudes.

All of these things were indicators of climate change.

Just about everyone by now knows that scientists overwhelmingly attribute the changes to so-called greenhouse gases, particularly carbon dioxide. Certainly Dr. Woodwell’s small audience did. They were fellows, mentors and friends of the Vineyard Vision program, which provides educational support to young Islanders committed to working for a more sustainable future.

But Dr. Woodwell provided extensive and alarming elaboration on the dimensions of the issue.

Carbon dioxide makes up only a small part of the earth’s atmosphere, about 392 parts per million at present, he said. But because of that fact, introducing a relatively small amount more into the system made a big change in proportion, with a big result.

Human activities were producing about 10 billion tons a year, most of it — 8.5 billion tons — came from burning fossil fuels, with another 1.5 billion tons coming from deforestation. About half was re-absorbed into the oceans and plants. But the five billion tons left over was increasing atmospheric CO2 by roughly 3 parts per million each year.

The result was warming.

However, he said the earth doesn’t warm uniformly.

Warming in the tropics increased evaporation, and that extra water vapor was then carried by atmospheric circulation to higher latitudes and elevations where it cooled, condensed and made rain.

“The energy of vaporization is dumped in those higher latitudes,” he said

Thus the tropics were not getting hotter as quickly because the energy was “transferred out” with the moisture. Further toward the poles though, warming was much faster. At the same time, the centers of all continents were drying out.

To make matters worse, plants and soils contain about three times as much carbon as the atmosphere now does.

“It turns out forests are second only to oceans in influence on climate,” he said.

And the world’s largest forests, in terms of both area and carbon content, were the boreal forests, growing in those areas more heavily affected by warming.

Not only had huge fires become increasingly common over the past couple of decades, but trees maladapted to the new climate were more vulnerable to all kinds of diseases and insect pests, like those borers in Alaska. Worse yet, those same parts of the world had deep deposits of peat and other organic matter, and warming increases the rate of decay of this organic matter, “dumping enormous amounts more carbon into the atmosphere.”

“We are pulling the climate out from under the life of the Earth,” he said.

And the cost of the “big, big dangerous” change to the world’s climate was not just environmental damage but human lives and social and economic breakdown.

And what can be done about it?

Dr. Woodwell mentioned a couple of specific actions. For a start, cut the use of fossil fuels dramatically and within a very few years, even if that means we can’t fly around the world, and maybe have to drive less and put up with other changes to our lifestyle.

Then we should stop deforestation and start reforestation on a grand scale.

One to two million square kilometers (about 400 to 800,000 square miles) of new forests could save about a billion tons of carbon, he said.

Beyond that, people had to adopt an attitudinal change. They had to disempower “irresponsible” corporations and empower responsible government.

More broadly, if everyone was to have the “fundamental rights” of somewhere to live, of clean water to drink and clean air to breathe, it would require “intensified government activity,” he said. For there was no doubt that in order to husband and fairly divide the resources of an increasingly-crowded planet there would have to be “more and more rules.”

“We need a new view of the world in which the environment is set forth as inviolate from here on,” he said.

Yet the prospects did not seem bright, he acknowledged.

“We have one whole political party in the nation at the moment that says we need less government and more growth. That’s ludicrous, absolutely upside-down. There is an increasing gap between what scientists know must be done . . . and what politicians are able to do at the moment,” he said.

Unless that changes, disaster loomed.

“The next world is coming day by day by day. If you want to see the dimensions of it just look at what’s happening,” said Dr. Woodwell.