Multi-model comparison of the volcanic sulfate deposition from the 1815 eruption of Mt. Tambora

Lauren Marshall (1) , Anja Schmidt (1) , Matthew Toohey (2, 3) , Ken S. Carslaw (1) , Graham W. Mann (1, 4) , Michael Sigl (5) , Myriam Khodri (6) , Claudia Timmreck (7) , Davide Zanchettin (8) , William T. Ball (9, 10) , Slimane Bekki (11) , James S. A. Brooke (12) , Sandip S. Dhomse (1) , Colin Johnson (13) , Jean-Francois Lamarque (14) , Allegra N. Legrande (15) , Michael J. Mills (14) , Ulrike Niemeier (7) , James O. Pope (16) , Virginie Poulain (17) , Alan Robock (18) , Eugene Rozanov (10, 9) , Andrea Stenke (9) , Timofei Sukhodolov (10) , Simone Tilmes (14) , Kostas Tsigaridis (19, 20) , Fiona Tummon (9, 21)

1 ICAS - Institute for Climate and Atmospheric Science [Leeds]
2 IFM-GEOMAR - Leibniz-Institut für Meereswissenschaften
3 MPI-M - Max-Planck-Institut für Meteorologie
4 NCAS - National Centre for Atmospheric Science [Leeds]
5 LUC - Laboratory of Environmental Chemistry [Villigen]
6 VARCLIM - Océan et variabilité du climat
7 MPI-M - Max Planck Institute for Meteorology
8 Department of Environmental Sciences, Informatics and Statistics [Venezia]
9 IAC - Institute for Atmospheric and Climate Science [Zürich]
10 PMOD/WRC - Physikalisch-Meteorologisches Observatorium Davos/World Radiation Center
11 STRATO - LATMOS
12 School of Chemistry [Leeds]
13 MOHC - Met Office Hadley Centre for Climate Change
14 ACOML - Atmospheric Chemistry Observations and Modeling Laboratory
15 GSFC - NASA Goddard Space Flight Center
16 BAS - British Antarctic Survey
17 PARVATI - Processus de la variabilité climatique tropicale et impacts
18 Department of Environmental Sciences [New Brunswick]
19 GISS - NASA Goddard Institute for Space Studies
20 CCSR - Center for Climate Systems Research [New York]
21 UiT - The Arctic University of Norway [Tromsø, Norway]

The eruption of Mt. Tambora in 1815 was the largest volcanic eruption of the past 500 years. The eruption had significant climatic impacts, leading to the 1816 "year without a summer", and remains a valuable event from which to understand the climatic effects of large stratospheric volcanic sulfur dioxide injections. The eruption also resulted in one of the strongest and most easily identifiable volcanic sulfate signals in polar ice cores, which are widely used to reconstruct the timing and atmospheric sulfate loading of past eruptions. As part of the Model Intercomparison Project on the climatic response to Volcanic forcing (VolMIP), five state-of-the-art global aerosol models simulated this eruption. We analyse both simulated background (no Tambora) and volcanic (with Tambora) sulfate deposition to polar regions and compare to ice core records. The models simulate overall similar patterns of background sulfate deposition, although there are differences in regional details and magnitude. However, the volcanic sulfate deposition varies considerably between the models with differences in timing, spatial pattern and magnitude. Mean simulated deposited sulfate on Antarctica ranges from 19 to 264 kg km⁻² and on Greenland from 31 to 194 kg km⁻², as compared to the mean ice-core-derived estimates of roughly 50 kg km⁻² for both Greenland and Antarctica. The ratio of the hemispheric atmospheric sulfate aerosol burden after the eruption to the average ice sheet deposited sulfate varies between models by up to a factor of 15. Sources of this inter-model variability include differences in both the formation and the transport of sulfate aerosol. Our results suggest that deriving relationships between sulfate deposited on ice sheets and atmospheric sulfate burdens from model simulations may be associated with greater uncertainties than previously thought.

Domains: Volcanology

Lauren Marshall, Anja Schmidt, Matthew Toohey, Ken S. Carslaw, Graham W. Mann, et al.. Multi-model comparison of the volcanic sulfate deposition from the 1815 eruption of Mt. Tambora. Atmospheric Chemistry and Physics, 2018, 18 (3), pp.2307 - 2328. ⟨10.5194/acp-18-2307-2018⟩. ⟨insu-01710396⟩