Absolute and Emissions-Intensity Targets

An absolute emissions target specifies the total quantity of greenhouse gases that an economy, sector or organisation aims to emit within a stated period or by a target year. An emissions-intensity target specifies emissions per unit of economic output, commonly GDP. The central difference is that an intensity target can be met even while total emissions increase.

What each target measures

• An absolute target can specify an emissions ceiling or a percentage reduction from a base-year emissions level. It concerns the total amount emitted within the target’s coverage.
• An emissions-intensity target specifies a reduction in the ratio of emissions to output. At the national level, this is commonly expressed as greenhouse gas emissions per unit of GDP.
• Both targets require clear accounting boundaries, including the gases and sectors covered, the reference period and the treatment of removals by carbon sinks.

Why their emissions outcomes differ

The relationship is total emissions = emissions intensity × output. Consequently, the emissions outcome of an intensity target depends on both the improvement in intensity and the growth of output.

• In a hypothetical example, if GDP grows by 50% and emissions intensity falls by 20%, total emissions become 1.5 × 0.8 = 1.2 times their initial level: a 20% increase despite meeting the intensity target.
• By contrast, meeting an absolute target requiring a 20% reduction means that covered emissions fall to 80% of their base-year level, irrespective of GDP growth.
• Intensity improvements can reduce total emissions if intensity falls sufficiently to outweigh output growth; rising emissions are therefore possible, not inevitable.

Implications for climate policy

• Absolute targets provide a clearer constraint on total covered emissions when achieved. However, a single target-year ceiling does not by itself determine cumulative emissions over the intervening years.
• Intensity targets link mitigation to economic activity and accommodate changes in output. They encourage lower-emission production but do not, by themselves, establish a fixed emissions ceiling.
• Neither target is automatically more ambitious: assessment requires examining its baseline, coverage, target level and, for intensity targets, assumptions about economic growth.
• India’s updated first Nationally Determined Contribution includes a target to reduce the emissions intensity of GDP, illustrating the national use of an intensity-based commitment.