Fig. 4: Scalings for storm mean intensities.

a, IDF curves for the 5-year return period for storms preceded by Td between 10 °C and 15 °C (blue) and for storms preceded by Td between 15 °C and 20 °C (red). Dashed light and dark grey curves indicate 1 × CC and 2 × CC rates relative to the blue line. b, Averaged convective fraction as a function of storm duration for each of the two storm categories shown in a. Note the double-logarithmic axis scaling in both panels (Methods).