An overview of the past, present and future of gravity‐wave drag parametrization for numerical climate and weather prediction models

TLDR

Gravity‑wave drag parametrization is a key component of numerical weather and climate models, and understanding its current status is essential for future improvements. This review surveys the past, present, and future of gravity‑wave drag parametrization, aiming to guide the development of next‑generation atmospheric models. The authors discuss the early history and latest developments, describing separate parametrizations for orographic and convective sources and newer spectrum‑based approaches that treat a range of gravity‑wave motions. They highlight differences in lower versus upper‑atmosphere parametrization, and identify emerging issues such as explicitly resolved waves and unparametrized processes that will require attention in future models.

Abstract

Abstract An overview of the parametrization of gravity ‐wave drag in numerical ‐weather prediction and climate simulation models is presented. The focus is primarily on understanding the current status of gravity wave drag parametrization as a step towards the new parametrizations that will be needed for the next generation of atmospheric models. Both the early history and latest developments in the field are discussed. Parametrizations developed specifically for orographic and convective sources of gravity waves are described separately, as are newer parametrizations that collectively treat a spectrum of gravity wave motions. The differences in issues in and approaches for the parametrization of the lower and upper atmospheres are highlighted. Various emerging issues are also discussed, such as explicitly resolved gravity waves and gravity wave drag in models, and a range of unparametrized gravity wave processes that may need attention for the next generation of gravity wave drag parametrizations in models.