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| Titel |
Extreme drought conditions over NE Iberia in early 19th century (1812-1825) and its possible relationship to major volcanic eruptions |
| VerfasserIn |
Mariano Barriendos, Marc Prohom, Arturo Sanchez-Lorenzo |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250035882
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| Zusammenfassung |
| Potential changes in the frequency, persistence and intensity of climate extremes (e.g.
heat waves, heavy precipitation and drought) are reported as key determinants of
future impacts and vulnerability. The more information about behavior and temporal
variability of such extremes in the past, the more accurate will be the projections in the
future.
In this work, an analysis of a mega-drought detected over NE Iberia in early nineteenth
century is made using two climatic information sources: instrumental and proxy data.
First, a unique rainfall series of Barcelona covering the period 1786-2009 has been
used. Here, data characteristics and metadata of the series is shown, especially
for the early period (1786-1843), that have been recently detected and digitized.
Second, in order to support and validate the instrumental series, proxy data from
historical documentary sources obtained in four locations in Catalonia are also
investigated.
Severe climatic drought conditions have been detected during the 1812-1825 period,
being especially significant in winter and autumn seasons. Around the sub-periods 1812-13,
1815-17 and 1822-24 three different pulses where the conditions were extremely dramatic are
detected. A similar mega-drought (intensity and duration) has not been detected in the whole
1786-2009 period.
An analysis of the atmospheric dynamic processes responsible for these conditions is
made based on the forcing effects of three coincident large volcanic events: unknown (1809),
Tambora (1815) and Galunggung (1822). It is well-known that great low latitude explosive
eruptions have a potential impact on climate via radiative effects (surface temperature
cooling) but also by means of dynamical forcing, i.e., Arctic Oscillation/Northern Annular
Mode (AO/NAM) or North Atlantic Oscillation (NAO) reinforcement (e.g. Robock, 2000;
Shindell et al., 2004; Fisher et al., 2007). A potential cause-effect relationship is
pointed out between both phenomena: major volcanism and drought conditions over
Iberia.
Fischer, E. M., J. Luterbacher, E. Zorita, S. F. B. Tett, C. Casty, and H. Wanner
(2007): European climate response to tropical volcanic eruptions over the last
half millennium, Geophys. Res. Lett., 34, L05707, doi:10.1029/2006GL027992.
Robock, A. (2000): Volcanic eruptions and climate, Rev. Geophys., 38, 191– 219.
Shindell, D. T., G. A. Schmidt, M. E. Mann, and G. Faluvegi (2004): Dynamic
winter climate response to large tropical volcanic eruptions since 1600, J.
Geophys. Res., 109, D05104, doi:10.1029/2003JD004151. |
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