Last Word
How "sinks" nearly sunk the Kyoto Protocol
For over a decade, the United Nations has been building a climate treaty aimed at reducing the emission of greenhouse gases into the atmosphere. The Kyoto Protocol has specific reduction targets for all industrial nations in addition to a number of other provisions that attempt to slow the rise of greenhouse gases in the atmosphere. The United States has chosen not to ratify this treaty. The primary focus of the treaty has been on encouraging countries to lower their emissions, most often through measures such as energy conservation or replacing fossil-fuel energy sources with renewable energy such as solar or geothermal.
In addition to slowing emissions, the treaty includes the opportunity for countries to gain emission-reduction credit by directly removing carbon dioxide from Earth's atmosphere. Referred to most often as "sinks," this provision avails of Mother Nature's carbon dioxide removal mechanism - growing trees and other vegetation - as a way to capture and remove this greenhouse gas from the atmosphere. This portion of the treaty, however, was highly controversial and nearly "sank" the treaty altogether.
The controversy surrounded two important aspects of biospheric exchange: First, many argued that the inclusion of biospheric uptake would only divert attention away from the more important work needed to transform industrial energy systems from fossil-based to non-carbon-based systems. Further emphasis is provided when one considers that even the most optimistic tree-planting scenarios indicate that "sinks" would have little impact on the long-term reductions required to slow climate change. However, opposing arguments noted that activities such as afforestation would assist in the near term and can be achieved at much lower cost than retrofitting power plants or expanding solar power.
The second point of contention surrounded the fact that plants can lose carbon dioxide to the atmosphere as readily as they can remove it. This fickleness of biospheric systems is difficult to predict or control and made the necessary accounting and verification extremely complex and potentially uncertain.
Controversy notwithstanding, sinks are a part of the Kyoto Protocol. Industrial nations can use tree-planting, management of grazing lands, agricultural lands, and the care and development of forests to offset their fossil-fuel emissions, though there are a number of limitations that constrain these activities to a secondary role in meeting their Kyoto targets.
In the past year, treaty discussions have now turned to another controversial topic related to vegetation and climate: deforestation. Since the lessindustrialized nations did not agree to reduction targets in the first round of negotiating, there is increased interest in including these nations now. And for many of these nations, deforestation activity is a larger source of greenhouse gases to the atmosphere than fossil-fuel combustion. Like the sinks discussion in the previous round, deforestation remains poorly quantified from a scientific perspective and a rather sensitive topic for many tropical nations. However, by starting early and partnering with ecologists and forest experts, it may be possible to both reduce deforestation and assist the lessdeveloped countries in leapfrogging over the fossil-fuel energy system to a renewable or other non-carbon energy system. If this is successful, we may be able to limit climate change and have a cleaner, greener planet.