On past temperatures and anomalous late‐20th‐century warmth

2003/07/08 by Michael Mann, Caspar Amman, R. S. Bradley +10 · 6 citations
Earth and Planetary Sciences · Environmental Science · #Archaeology #Atmospheric sciences #Climate change #Climate model #Climate variability and models #Climatology #Environmental science #Forcing (mathematics) #Geography #Geology #Greenhouse gas #Natural (archaeology) #Oceanography #Plant Water Relations and Carbon Dynamics #Tree-ring climate responses

paper · doi:10.1029/2003eo270003

openalex publication_date 2003/07/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/02

Abstract

Evidence from paleoclimatic sources and modeling studies support AGU's official position statement on climate change and greenhouse gases; namely that there is a compelling basis for concern over future climate changes, including increases in global‐mean surface temperatures, due to increased concentrations of greenhouse gases, primarily from fossil fuel burning. More specifically a number of reconstructions of large‐scale temperature changes over the past millennium support the conclusion that late‐20th century warmth was unprecedented over at least the past millennium. Modeling and statistical studies indicate that such anomalous warmth cannot be fully explained by natural factors, but instead, require a significant anthropogenic forcing of climate that emerged during the 19th and 20th centuries.

Citations

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Cited by

• Extra-tropical Northern Hemisphere land temperature variability over the past 1000 years
• Borehole climate reconstructions: Spatial structure and hemispheric averages
• Proxy-Based Northern Hemisphere Surface Temperature Reconstructions: Sensitivity to Method, Predictor Network, Target Season, and Target Domain
• Millennial temperature reconstruction intercomparison and evaluation
• The Spatial Extent of 20th-Century Warmth in the Context of the Past 1200 Years
• Hockey stick graph (global temperature) [wikipedia]