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Base Year Recalculation

Base year recalculation is the process of adjusting an organisation’s historical base year emissions to account for significant structural changes, ensuring meaningful year-on-year comparison.

What is Base Year Recalculation?

When an organisation undergoes structural changes — mergers, acquisitions, divestments, or significant changes in calculation methodology — the base year may no longer represent a comparable starting point. The GHG Protocol requires organisations to establish a base year recalculation policy that defines when recalculation is triggered (typically for changes exceeding a materiality threshold, often 5% of base year emissions). Without recalculation, reported reductions may be artificial (from divestments) or hidden (from acquisitions).

Practical Examples

1

A company acquires a subsidiary that increases its base year Scope 1 emissions by 15%, triggering a base year recalculation to include the subsidiary’s historical emissions.

2

A company divests a high-emission division and recalculates its base year downward, ensuring its reduction targets remain meaningful against the restructured boundary.

How Climatise Helps

Climatise maintains a full audit trail of base year emissions and supports recalculation by tracking structural changes and their impact on the historical inventory.

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