Volcanic Contribution to Decadal Changes in Tropospheric Temperature

TitleVolcanic Contribution to Decadal Changes in Tropospheric Temperature
Publication TypeJournal Article
Year of Publication2014
Authors, Bonfils Céline, Painter Jeffrey, Zelinka Mark, and Taylor Karl
Journalnature Geoscience
Volume7
Pages185-189
Date Published02/2014
Abstract / Summary

Despite continued growth in atmospheric levels of greenhouse gases, global mean surface and tropospheric temperatures have shown slower warming since 1998 than previously 1–5. Possible explanations for the slow-down include internal climate variability 3,4,6,7 , external cooling influences 1,2,4,8–11 and observational errors 12,13 . Several recent modelling studies have examined the contribution of early twenty-first-century volcanic eruptions 1,2,4,8 to the muted surface warming. Here we present a detailed analysis of the impact of recent volcanic forcing on tropospheric temperature, based on observations as well as climate model simulations. We identify statistically significant correlations between observations of stratospheric aerosol optical depth and satellite-based estimates of both tropospheric temperature and short-wave fluxes at the top of the atmosphere. We show that climate model simulations without the effects of early twenty-first-century volcanic eruptions overestimate the tropospheric warming observed since 1998. In two simulations with more realistic volcanic influences following the 1991 Pinatubo eruption, differences between simulated and observed tropospheric temperature trends over the period 1998 to 2012 are up to 15% smaller, with large uncertainties in the magnitude of the effect. To reduce these uncertainties, better observations of eruption-specific properties of volcanic aerosols are needed, as well as improved representation of these eruption-specific properties in climate model simulations.

URLhttp://www.nature.com/ngeo/journal/v7/n3/full/ngeo2098.html
DOI10.1038/NGEO2098
Journal: nature Geoscience
Year of Publication: 2014
Volume: 7
Pages: 185-189
Date Published: 02/2014

Despite continued growth in atmospheric levels of greenhouse gases, global mean surface and tropospheric temperatures have shown slower warming since 1998 than previously 1–5. Possible explanations for the slow-down include internal climate variability 3,4,6,7 , external cooling influences 1,2,4,8–11 and observational errors 12,13 . Several recent modelling studies have examined the contribution of early twenty-first-century volcanic eruptions 1,2,4,8 to the muted surface warming. Here we present a detailed analysis of the impact of recent volcanic forcing on tropospheric temperature, based on observations as well as climate model simulations. We identify statistically significant correlations between observations of stratospheric aerosol optical depth and satellite-based estimates of both tropospheric temperature and short-wave fluxes at the top of the atmosphere. We show that climate model simulations without the effects of early twenty-first-century volcanic eruptions overestimate the tropospheric warming observed since 1998. In two simulations with more realistic volcanic influences following the 1991 Pinatubo eruption, differences between simulated and observed tropospheric temperature trends over the period 1998 to 2012 are up to 15% smaller, with large uncertainties in the magnitude of the effect. To reduce these uncertainties, better observations of eruption-specific properties of volcanic aerosols are needed, as well as improved representation of these eruption-specific properties in climate model simulations.

DOI: 10.1038/NGEO2098
Citation:
2014.  "Volcanic Contribution to Decadal Changes in Tropospheric Temperature."  nature Geoscience 7: 185-189, pp. 185-189.  https://doi.org/10.1038/NGEO2098.