Global Multi‐Model Eddy Dissipation Rate Probability Density Functions for Clear‐Air Turbulence Under Climate Change

Abstract

Atmospheric turbulence poses a major risk to aviation, and it is expected to intensify as a response to climate change. The probability density functions (PDFs) of dozens of different clear‐air turbulence (CAT) diagnostics have been found to shift to higher values in response to climate change, consistent with strengthened vertical wind shear at cruising altitudes. The response of the PDF of the eddy dissipation rate (EDR), which is the internationally endorsed measure of turbulence strength, has not previously been studied, however. This study aims to quantify the impacts of these changes in the upper–tropospheric and lower–stratospheric dynamics on global CAT by 2100. By converting 21 CAT diagnostics from multiple climate model simulations into EDR for the historical period of 1950–1980 and the future period of 2070–2100, we find greater probabilities in the right–hand tail of the PDF in the future period compared with the historical period. Multi‐diagnostic‐model metrics show relative increases of 1%–15% in light, 2%–20% in light‐to‐moderate, 3%–20% in moderate, 8%–45% in moderate‐to‐severe, and 10%–50% in severe CAT by the future period depending on scenarios, regions, and seasons. These findings indicate that CAT will become significantly more frequent across all aviation‐relevant intensity levels as the climate continues to change.