A Perspective on Shortwave Radiative Energy Flows in the Earth System

The study of shortwave (SW) radiation and its interactions with our planet has proven critical for advancing the understanding of the Earth–atmosphere system. Here, the author shares an accessible and high-level perspective on recent progress, surprises encountered, and promising future research directions^a. A brief context for the study of SW radiation is provided, after which three specific aspects are focused upon that the author considers particularly important. First, the significance of three-dimensional (3D) SW radiative effects is highlighted via impacts on surface downward SW radiation in complex cloud fields. Crucially, it is shown that probability distributions of surface radiation can only be reliably simulated when accounting for 3D effects, which has implications for various applications and next-generation atmospheric modeling. Second, the significance of the often overlooked diurnal cycle in global top-of-atmosphere upward SW radiation is underscored by quantifying the controlling properties and processes. Opportunities for improved future satellite observations of the global diurnal cycle are noted. Third, the wealth of information provided by the spectral dimension of SW radiation is demonstrated through the extraction and attribution of SW spectral signatures. It is argued that further exploration of the spectral dimension, aided by the recently launched and upcoming suite of spectrally resolved SW satellite observations, promises a new era of SW radiation research.