Separating Anthropogenically- and Naturally-Caused Temperature Trends: A Systematic Approach Based On Climate Memory Analysis

Abstract

Separating anthropogenic and natural contributions to global warming is crucial for understanding and predicting climate change, but it is challenging due to the complexity of the climate system. In this study, we try to address this issue by estimating the anthropogenic forcing impacts with its long-term persistence features properly considered. In this way, a data-driven approach is proposed to decompose the observed trends from global and regional scales into anthropogenically- and naturally-caused trends. We find that there is a continuous anthropogenic global warming trend since the beginning of the last century, even during the recent global warming hiatus period. On regional scales, the anthropogenically-forced trends among regions are found at a similar level, while their unevenly distributed warming trends among regions may be attributed to natural causes. Our findings provide new insight into climate warming, and our approach based on persistence analysis provides a new perspective for attribution studies. © 2023 The Authors.