Journal Highlights

Separating natural and human-induced warming trends

Both natural and human-induced influences have changed twentieth-century climate, but their relative roles and regional impacts are still under debate. For example, most model-based studies point to increasing human-generated greenhouse gas and aerosol concentrations as the dominant cause of global surface warming after 1967, while some empirical analyses suggest that solar variability accounts for as much as 69% of warming seen in the past 100 years and 25–35% of recent warming. To help resolve this, Lean and Rind (2008) analyzed the best available estimates of both natural and human-induced climate influences and compared them with observed surface temperatures across the globe from 1889 to 2006. They found that solar forcing contributed negligible long-term warming in the past 25 years and 10% of the warming in the past 100 years. Additionally, in contrast with recent model results by the Intergovernmental Panel on Climate Change, which estimates that anthropogenic warming has minimum values in the tropics and increases steadily from 30°N to 70°N, the authors found that the zonal surface temperature changes from the historical surface temperature record are more pronounced between 45°S and 50°N.

RSS

Recent Highlights Across AGU Publications

Eos.org: Earth & Space Science News

View more Earth and space science news from Eos

Download the App

New Android App Available!

Google Play Store Logo

Download the Geophysical Research Letters app from the Google Play Store

iOS App for iPad or iPhone

GRL IOS App

Download the Geophysical Research Letters app from the Apple store


AGU Career Center


AGU Unlocked


Featured Special Collection

Early Results: Juno at Jupiter 

Early results from Juno's mission at Jupiter including approach to Jupiter and the first perijove pass (PJ1). Juno's scientific objectives include the study of Jupiter's interior, atmosphere and polar magnetosphere with the goal of understanding Jupiter's origin, formation and evolution. This collection of papers provides early results from Juno's measurements of the gravity and magnetic fields, deep atmospheric microwave sounding, infrared, visible and ultraviolet images/spectra and an array of fields and particles instruments as well as context for the early results with respect to current theory and models of Jupiter's formation and evolution. Topics include both Juno - Jupiter related theoretical models and data analysis as well as collaborative observations made from Earth based assets.