Future Projections Summary

The average depicted here is based on a long-term, 30-year period. To ensure a fair comparison, this average should only be compared with other averages that are also derived from the same 30-year duration. This allows for a meaningful evaluation of how a particular variable has changed over time.

In terms of the range around this average, it illustrates the variability within the Global Climate Models (GCMs) used. The highest and lowest points within this range are determined by the maximum and minimum averages produced by individual GCMs. Meanwhile, the central average that is presented reflects the mean value of the ensemble. This provides a comprehensive picture, accounting for both the consensus value (average) and the extent of model variability (range).

These values are future projections. Therefore, they take into account the SSP370 scenario.

Modeled Historical Summary

The average depicted here is based on a long-term, 30-year period. To ensure a fair comparison, this average should only be compared with other averages that are also derived from the same 30-year duration. This allows for a meaningful evaluation of how a particular variable has changed over time.

In terms of the range around this average, it illustrates the variability within the Global Climate Models (GCMs) used. The highest and lowest points within this range are determined by the maximum and minimum averages produced by individual GCMs. Meanwhile, the central average that is presented reflects the mean value of the ensemble. This provides a comprehensive picture, accounting for both the consensus value (average) and the extent of model variability (range).

These values are part of the modeled historical dataset meaning that the focus is on recreating, as accurately as possible, the observed climate values. Therefore, future scenarios are not included in the model.

Climate Forcing

Radiative forcing, often called climate forcing, gauges Earth's energy balance. It compares the energy from the sun that reaches Earth to the energy Earth emits back into space. Ideally, these energy amounts should be equal, but various forcings can upset this balance. Some factors, like volcanic eruptions or Earth's orbital changes, are natural. Others, such as increased atmospheric CO2 or altered land use, result from human actions.

In climate research, forcings are denoted in watts per square meter, using 1750—a time roughly marking the start of the industrial revolution—as a reference. This allows scientists to assess how Earth's energy balance has changed since then. Positive forcings indicate the Earth retains more energy than it emits, causing warming. Conversely, negative forcings show Earth emits more energy than it absorbs, leading to cooling.

The IPCC, in its reports, combines forcings with socioeconomic predictions to forecast possible climate futures. Their recent report introduced Shared Socioeconomic Pathways (SSPs) to depict potential climate trajectories. Each SSP merges a socioeconomic story with a specific warming level, described by its forcing, to outline five potential Earth futures.

The WY-Adapt scenario is based on SSP370, which blends two parts: SSP3, a moderate socioeconomic forecast, and a projected forcing of 7.0 watts per square meter by 2100. This means a 7 w/m² increase since 1750.

Climate Projection

A climate projection is a simulation of Earth's climate in future decades, given assumptions about future greenhouse gas concentrations in the atmosphere and how earth systems interact and react to those greenhouse gas concentrations. Climate projections are generated using global climate models (GCMs) and are sometimes downscaled to produce data at fine spatial scales. Climate projections are not weather projections; they cannot tell us what the weather will be like on any given day or in a year in the future. Instead, climate projections tell us what conditions in the future are going to be like on average over long time periods, often expressed as 30-year periods called climate normals.

Shared Socioeconomic Pathways (SSPs)