"More than a beast, but much less than an angel" is how William Schlesinger, institute director at the Cary Institute for Ecosystem Studies in Millbrook, sees the human response to dealing with the current environmental crisis. In a recent talk at the institute, Schlesinger had advice for President Barack Obama, but first he gave an enthusiastic audience some background and personal reflection on the unfolding changes to our world.

Showing a slide of the 4.5-inch long blue-winged warbler, one of his favorite birds, Schlesinger spoke of his first noticing environmental changes, including declines in the populations of common species. As a young scientist, he studied plant succession in the southeastern United States and saw how vegetation responded to large-scale environmental changes, not just to those in the immediate area. What were those changes and what was responsible for them?

Some answers to the questions were found in the studies of ice cores done in the Arctic. The earth’s mean temperatures and carbon dioxide levels were reasonably stable from 12,000 years ago to the recent past, including through the development of modern society with its Industrial Revolution. It was only the introduction of wide-spread mining, especially for coal, with its destruction of the earth’s crust, that was to dramatically elevate carbon dioxide levels and temperatures.

Humans have accelerated by 10 times the rate of material production. Every day people in the developed world use the equivalent energy output of 100 personal servants.This energy is from those fossil fuels or hydrocarbons in the earth’s crust. A new generation of chemicals was added to that toxic brew during the second half of the 20th century. Many of these chemicals had benefits as well as unintended consequences for the environment.

Schlesinger then asked how a planet with a population increase of 500 million people could continue to find sufficient resources, clean up its environment, and leave room for other species, including the blue-winged warbler, and what could our new president do about this whole range of environmental problems?

To begin, Schlesinger urged Obama to restore American support for family planning efforts around the world. Also on the world stage, he asked the United States to rejoin the international talks on global warming and climate change.The world is past the figure of 350 parts per million of carbon in the atmosphere, still thought to be the upper limit for reversible change. The various plans for capping emissions and trading unused carbon credits are very complicated and susceptible  to abuse.

The big hope for Schlesinger lies in new technology and a big investment in renewable energy. Referring back to the title of this talk, he said that fostering new technologies is "the angel in our nature."

When an audience member asked if Obama would listen to the advice, Schlesinger smiled and mentioned that John Holdren, the science advisor to the administration, had spoken recently at the Cary Institute.

During the question and answer period, the controversial issue of cap and trade came up several times, with many people worried about the complexity of the proposed plans. On a related topic, Joel Tyner, environmental chair of the Dutchess County Legislature, urged the introduction of a county carbon tax to reduce global warming. Boulder, Colo., has recently passed one and projects an average tax increase of $1.33 a month for homes and $3.80 for businesses. Tyner said there is more information online and also a petition to the Dutchess County Legislature at petitiononline.com/carbontx/.