Model Intercomparison

The figures below show study's projections of total annual CO₂ emissions from global electricity generation under three different scenarios.

Studies assessing the temperature outcomes of various policy scenarios estimate that currently implemented energy and climate policies are likely to lead to a global temperature rise of 2.1–2.4 °C above pre-industrial levels by 2100. The ambition reflected in post-Glasgow Nationally Determined Contributions (NDCs) would slightly curb this increase, limiting warming to around 2.0–2.2 °C. If countries follow through on their long-term targets (LTTs) after achieving their 2030 NDC commitments, the projected temperature rise could be further reduced and stabilise at approximately 1.7–1.8 °C. (van de Ven et al., 2023). We find that model projections based on NDCs and LTTs globally (scenario NDC_LTT_baseWACC) are aligned with AR6 SSP2 C2 and C3 futures, while scenarios with less mitigation ambition (NDC_EI_baseWACC; Fragmented) are within the range of >2°C futures, as represented in C5 futures. Model differences are more evident in these latter two scenarios, as TIAM projects higher emissions reductions that GCAM, despite the converging effect of modelling a common set of current energy and climate policies.