Trees Aid Biosphere Balance

WORKING out how Earth's biosphere handles carbon dioxide (CO2) can have a political angle.

Environmental analyst John Taylor at the Australian National University in Canberra noted last month in the journal Nature that a consensus is developing that uptake of CO2 by the land biosphere is a crucial aspect of global warming. ``You might want to `discover' a substantial CO2 sink in your region if this can be used to offset industrial emissions of CO2; on the other hand, this may bring with it restrictions on land use with concomitant economic penalties,'' he said. Northern Hemisphere industrial countries have already run into this. As they step up forest exploitation, evidence is building that these forests may be an important absorber of CO2. More than science is at stake as scientists chart the details of Earth's carbon-dioxide ``breathing.''