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Aerosols interact with radiation and clouds. Substantial progress made over the past 40 years in observing, understanding, and modeling these processes helped quantify the imbalance in the Earth's radiation budget caused by anthropogenic aerosols, called aerosol radiative forcing, but uncertainties remain large. This review provides a new range of aerosol radiative forcing over the industrial era based on multiple, traceable, and arguable lines of evidence, including modeling approaches, theoretical considerations, and observations. Improved understanding of aerosol absorption and the causes of trends in surface radiative fluxes constrain the forcing from aerosol-radiation interactions. A robust theoretical foundation and convincing evidence constrain the forcing caused by aerosol-driven increases in liquid cloud droplet number concentration. However, the influence of anthropogenic aerosols on cloud liquid water content and cloud fraction is less clear, and the influence on mixed-phase and ice clouds remains poorly constrained. Observed changes in surface temperature and radiative fluxes provide additional constraints. These multiple lines of evidence lead to a 68% confidence interval for the total aerosol effective radiative forcing of -1.6 to -0.6 W m −2 , or -2.0 to -0.4 W m −2 with a 90% likelihood. Those intervals are of similar width to the last Intergovernmental Panel on Climate Change assessment but shifted toward more negative values. The uncertainty will narrow in the future by continuing to critically combine multiple lines of evidence, especially those addressing industrial-era changes in aerosol sources and aerosol effects on liquid cloud amount and on ice clouds. Plain Language SummaryHuman activities emit into the atmosphere small liquid and solid particles called aerosols. Those aerosols change the energy budget of the Earth and trigger climate changes, by scattering and absorbing solar and terrestrial radiation and playing important roles in the formation of

As individuals serving on the AGU Advances editorial board, we condemn racism, affirm that Black Lives Matter, and recognize that inequality is built into the systems that have allowed us to prosper. We aim to persistently foster discussion about racism, inequity, and the need to make our community more diverse and inclusive. This will help AGU Advances do a better job in publishing important science that inclusively reflects the ideas and contributions of all in our community. These are challenging times. The context for the killing of George Floyd and too many others has compelled people across the world to confront the reality of the racism built into our institutions, including the science and education enterprise. For many, this is their lived experience. For others, thinking about this is uncomfortable: Even the most well-intentioned must come to grips with their role in perpetuating inequalities of access and opportunity.

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In 2020, we all faced the enormous and unexpected challenges of the Covid-19 pandemic, with its host of new and competing demands on our time. Thus, we are especially grateful to the 154 people who provided reviews for AGU Advances and helped our fledgling journal complete its first year. Peer-review is essential to the process of doing and publishing science, and our reviewers have helped define our new journal by indicating papers expected to have broad impact that advance a discipline, have broad impact across disciplines, or have policy relevance. All papers submitted to AGU Advances first go through an editorial consultation. We are committed to respecting reviewers' time and only send papers for review that the consulting editors agree meet our criteria. Sometimes this means we send papers back to the authors with suggestions how to improve the fit to our journal. Another way we try to streamline the review process is by giving the authors the option to transfer reviews if after review we decide the paper is better suited to another AGU journal. As a relatively new journal, we still have few enough reviewers that we do not want to identify them by name. Nonetheless, you know who you are. Please accept our sincere thanks for generously sharing your expertise and working to improve AGU Advances.