Negative Emissions From Stopping Deforestation and Forest Degradation

Abstract The magnitude of gross sources and sinks of carbon from current land management practices suggests that, if deforestation and forest degradation from human activities were stopped, and forests were allowed to recover (e.g., harvested forests and the fallows of shifting cultivation), an estimated 4.4 PgC might be removed from the atmosphere each year for the next century or more. Although the cumulative removal by 2100 would amount to ~ 360 PgC, this long-term estimate represents a gross removal. The net removal would be considerably less because carbon held presently in wood products and in cultivated and disturbed soils would be emitted to the atmosphere even if further deforestation and harvests were stopped. Accounting for these committed emissions, a more likely estimate is that 100–130 PgC might be removed from the atmosphere by 2100 in recovering forests. The quantity is not enough to counter emissions under a business-as-usual future, but it is large (30–60%) relative to the carbon emissions allowable for staying under a warming of 2°C. Thus, land management, and forest management in particular, could help stabilize concentrations of CO2 in the atmosphere and provide a bridge for the transition from fossil fuels to renewable forms of energy.