This technical brief evaluates Global Warming Level (GWL) frameworks as an alternative to traditional scenario-year approaches for assessing climate hazards and informing energy system planning. Conventional climate assessments rely on projections tied to specific emissions pathways and future time horizons. This approach conflates uncertainties related to socioeconomic assumptions with those of climate model responses. In contrast, the GWL framework conditions climate outcomes on predefined global average temperature thresholds, effectively isolating the physical magnitude of global warming from model-driven regional variability.
By enabling comparisons across multiple models and emissions pathways at consistent warming levels, GWL-based analysis can provide a clearer interpretation of climate signals. However, each framework represents uncertainty differently: scenario-year approaches emphasize temporal evolution and pathway dependence, while GWL approaches focus on physical climate states independent of timing.
For utility planning, spanning infrastructure design, risk assessment, and regulatory compliance, these two frameworks are ultimately complementary. Rather than choosing one over the other, energy sector decision-makers can utilize hybrid approaches that integrate the temporal strengths of scenario-year modeling with the physical risk thresholds of the GWL framework. Finally, the brief identifies how emerging advances in climate modeling and artificial intelligence could further enhance these integrated assessments.
Authors Erik Smith