Response to Merritts et al. (2023): The Anthropocene is complex. Defining it is not

Merritts et al. (2023) misrepresent Paul Crutzen’s Anthropocene concept as encompassing all significant anthropogenic impacts, extending back many millennia. Crutzen's definition reflects massively enhanced, much more recent human impacts that transformed the Earth System away from stability of Holocene conditions. His an epoch (hence ‘cene’ suffix) is consistent with strikingly distinct sedimentary record accumulated since mid-20th century. Waters (2022) highlighted a Great Acceleration Event Array (GAEA) stratigraphic event markers are indeed diverse and complex but also tightly clustered around 1950 CE, allowing ultra-high resolution characterization correlation clearly recognisable chronostratigraphic base. The ‘Anthropocene event’ offered by al., following Gibbard (2021, 2022), highly nuanced obfuscates transformative impact Anthropocene. restricted meaning term ‘event’ in geology to conform usual Quaternary practice improve its utility. They simultaneously recognized evidence-based Anthropogenic Modification Episode explicitly defined than interpretive interdisciplinary 2022). advance science best served through developed concepts supported circumscribed terminology; indeed, improvements stratigraphy over decades have been achieved increasingly precise definitions, especially for units, not retaining vague terminology.