The three box plots each represent the outputs from global climate models (GCMs) under three
different forcing scenarios, 1) a historical scenario (where the GCM years 1971-2000 have been utilized here), 2) two future scenarios, RCP4.5 and RCP8.5, each representing a different future under climate emission mitigation (RCP4.5) and a business-as-usual emission scenario (RCP8.5).
Each marker in the box plots represent an individual GCM's projections for the
years indicated in the indicated season.
The historical result is calculated by averaging the yearly values of the variable's average(or sum) over the indicated season. The average is calculated over the GCM years of 1971-2000.
The future projection is calculated by averaging the yearly values of the variable's average(or sum) over the indicated season. The average over 30 years of data gives an indication of the climate for that variable in the future period.
The boxplot of projections from all models in the Integrated Scenarios project gives a range of projections under each future scenario. The multi-model mean from each future scenario may be useful in comparing the scenario results. In this view, one scan compare the projections from the different scenarios by considering the multi-model mean as the signal for change from the ensemble of models under CMIP5 and by considering the model spread as a measure of the uncertainty in these projections.