资源环境科技发展态势分析平台

A warming trend of 2.1 (±0.4) m°C yr^‐1 in bottom waters (4500 to 5900 dbar) spreading north from Antarctica through the Brazil Basin is quantified by comparing 2019–2020 data from a new Deep Argo regional pilot array to 1989–1995 data from full‐depth zonal and meridional hydrographic sections occupied across the basin before and during the World Ocean Circulation Experiment. Additionally, float temperatures are about 0.045 °C warmer than those from a long‐term climatology in those same bottom waters. Lower North Atlantic Deep Water in the basin shows no detectable warming, but Upper North Atlantic Deep Water exhibits evidence of warming in both analyses. The bottom‐intensified warming results in a reduction in vertical density stratification between the bottom and deep waters of about 1% decade^‐1. This change is in contrast with the effects of surface‐intensified warming, which tends to increase vertical density stratification.