Assessing the impact of large volcanic eruptions of the last millennium (850–1850 CE) on Australian rainfall regimes
Explosive volcanism is an important natural climate forcing, impacting global surface temperatures and regional precipitation. Although previous studies have investigated aspects of the impact of tropical volcanism on various ocean–atmosphere systems and regional climate regimes, volcanic eruptio...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2018-06-01
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| Series: | Climate of the Past |
| Online Access: | https://www.clim-past.net/14/811/2018/cp-14-811-2018.pdf |
| Summary: | Explosive volcanism is an important natural climate forcing, impacting global
surface temperatures and regional precipitation. Although previous studies
have investigated aspects of the impact of tropical volcanism on various
ocean–atmosphere systems and regional climate regimes, volcanic eruptions
remain a poorly understood climate forcing and climatic responses are not
well constrained. In this study, volcanic eruptions are explored in
particular reference to Australian precipitation, and both the Indian Ocean
Dipole (IOD) and El Niño–Southern Oscillation (ENSO). Using nine realisations
of the last millennium (LM) (850–1850 CE) with different time-evolving forcing
combinations, from the NASA GISS ModelE2-R, the impact of the six largest
tropical volcanic eruptions of this period are investigated. Overall, we find
that volcanic aerosol forcing increased the likelihood of El Niño and
positive IOD conditions for up to four years following an eruption, and
resulted in positive precipitation anomalies over north-west (NW) and
south-east (SE) Australia. Larger atmospheric sulfate loading during larger
volcanic eruptions coincided with more persistent positive IOD and El Niño
conditions, enhanced positive precipitation anomalies over NW Australia, and
dampened precipitation anomalies over SE Australia. |
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| ISSN: | 1814-9324 1814-9332 |