A Comparison of Top‐Of‐Atmosphere Radiative Fluxes From CERES and ARISE

Abstract Uncertainty in Arctic top‐of‐atmosphere (TOA) radiative flux observations stems from the low sun angles and heterogeneous scenes. Advancing our understanding of climate system requires improved TOA fluxes. We compare Cloud Earth's Radiant Energy System (CERES) fluxes with Radiation‐IceBridge Sea Ice Experiment (ARISE) airborne measurements using two approaches: grid box averages instantaneously matched footprints. Both approaches indicate excellent agreement longwave good shortwave (SW), within 2σ uncertainty considering all error sources (CERES radiometer calibration, inversion, sampling). While SW differences are uncertainty, both show a ∼−10 W m −2 average CERES‐aircraft difference. Investigating source this negative difference, we find substantial sensitivity to sea ice concentration data set. Switching imager‐based passive microwave‐based CERES inversion process reduces partly cloudy scene anisotropy In long‐term, more accurate needed reduce uncertainties. imager microwave data, short‐term, could improve polar regions, additional testing is required. Our analysis indicates that calibration sampling limit ability place strong constraints (<±7%) on aircraft measurements.