How we calculate
From answers to acres.
Every number on Climate Tribe is traceable. Here is exactly how we estimate your annual footprint and how your subscription translates into trees in the ground.
01
Footprint estimate
The quiz collects six high-impact lifestyle inputs: home heating fuel, electricity use, diet, car mileage, public transport, and flights. Each answer carries an emissions coefficient (tCO₂e per unit) derived from BEIS 2024 conversion factors for the UK and EEA national inventories for European users.
We deliberately keep the quiz short. A longer survey marginally improves precision but dramatically reduces completion. Our model targets ±15% accuracy versus a full ISO 14067 household assessment.
02
Tonnes to trees
A mature mixed-species temperate tree sequesters approximately 21 kg of CO₂ per year over a 40-year growth curve, averaging roughly 0.8 tCO₂e across its lifetime. We apply a 30% buffer for mortality, fire and reversal risk per Verra VM0047 guidance.
The result: each tonne of your annual footprint requires roughly 1.8 verified trees per year to offset on a lifetime basis. Your monthly plan funds planting at that rate plus monitoring overhead.
03
Verification
Each operator submits geotagged planting records within 90 days of subscription payment. We sample 5% of plots annually via independent foresters and publish survival rates by site in our reports.
Carbon claims are conservative. We only count sequestration once trees pass their third-year survival check.
Sources
- · UK BEIS Greenhouse Gas Conversion Factors (2024 release)
- · European Environment Agency, National Emissions Inventories
- · Verra VM0047 Afforestation, Reforestation and Revegetation methodology
- · IPCC AR6, Working Group III, Chapter 7 (AFOLU)
- · UK Woodland Carbon Code v3.0