For some twenty years now, environmental economists have argued that the most efficient way for society to control pollution is through the use of 'market mechanisms'.

"You can't miss these bags," said Clive Mutunga, an environmental economist in Kenya who is seeking to clean up the mess.

As a consequence, growth-oriented environmental economists propose massive government intervention into switching sources of energy production, favouring wind, solar, hydroelectric, and nuclear.

The main difference an environmental economist would argue exists between the two methods, however, is the total cost of the regulation.

Most environmental economists have been trained as economists.

Most were ecosystem ecologists or mainstream environmental economists, with the exception of Daly.

-ecology question, says an emerging group of environmental economists, is far more elusive.

Some environmental economists have been critical of the Kyoto Protocol.

The UN study is part of a growing initiative from environmental economists to give specific values to natural assets such as soil, water and forests.

The environmental economists' alternative is to charge fees that discourage carbon emissions, raising the prices of fuels according to their carbon content.