Ida Sognnæs
@idasogn.bsky.social
Researcher on emissions scenarios, energy-economic modelling, use of models for climate policy. CICERO Center for International Climate Research, Oslo, Norway.
The purpose of scenario analysis is not to provide precise estimates of isolated scenario outcomes, but to show the implications of choices and trade-offs. Different models provide different views. Statistical values from an arbitrary sample does little to convey this.
October 2, 2025 at 10:10 AM
The purpose of scenario analysis is not to provide precise estimates of isolated scenario outcomes, but to show the implications of choices and trade-offs. Different models provide different views. Statistical values from an arbitrary sample does little to convey this.
It is partly because the dominant model, REMIND, is responsible for a very large share (42%) of the 1.5°C scenarios – much larger than the dominant study, ENGAGE (26%). But also because many scenario outcomes are strongly model dependent – models have distinct “fingerprints”.
October 2, 2025 at 10:10 AM
It is partly because the dominant model, REMIND, is responsible for a very large share (42%) of the 1.5°C scenarios – much larger than the dominant study, ENGAGE (26%). But also because many scenario outcomes are strongly model dependent – models have distinct “fingerprints”.
Median global GHG reductions by 2030 — a widely recognized target, used in the Sharm el-Sheikh Implementation Plan — changes from 43% to 50% (relative to 2019) when only a single model is excluded. This is despite more than 50 models submitting scenarios to the IPCC database.
October 2, 2025 at 10:10 AM
Median global GHG reductions by 2030 — a widely recognized target, used in the Sharm el-Sheikh Implementation Plan — changes from 43% to 50% (relative to 2019) when only a single model is excluded. This is despite more than 50 models submitting scenarios to the IPCC database.