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| Titel |
Asian Monsoon Variability from the Monsoon Asia Drought Atlas (MADA) and Links to Indo-Pacific Climate |
| VerfasserIn |
Caroline Ummenhofer, Rosanne D'Arrigo, Kevin Anchukaitis, Manuel Hernandez, Brendan Buckley, Edward Cook |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250097646
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| Publikation (Nr.) |
 EGU/EGU2014-13249.pdf |
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| Zusammenfassung |
| Drought patterns across monsoon and temperate Asia over the period 1877–2005 are linked
to Indo-Pacific climate variability associated with the El Niño-Southern Oscillation (ENSO)
and the Indian Ocean Dipole (IOD). Using the Monsoon Asia Drought Atlas (MADA)
composed of a high-resolution network of hydroclimatically sensitive tree-ring records with a
focus on the June-August months, spatial drought patterns during El Niño and IOD
events are assessed as to their agreement with an instrumental drought index and
consistency in the drought response amongst ENSO/IOD events. Spatial characteristics in
drought patterns are related to regional climate anomalies over the Indo-Pacific
basin, using reanalysis products, including changes in the Asian monsoon systems,
zonal Walker circulation, moisture fluxes, and precipitation. A weakening of the
monsoon circulation over the Indian subcontinent and Southeast Asia during El
Niño events, along with anomalous subsidence over monsoon Asia and reduced
moisture flux, is reflected in anomalous drought conditions over India, Southeast
Asia and Indonesia. When an IOD event co-occurs with an El Niño, severe drought
conditions identified in the MADA for Southeast Asia, Indonesia, eastern China and
central Asia are associated with a weakened South Asian monsoon, reduced moisture
flux over China, and anomalous divergent flow and subsidence over Indonesia.
Variations in the strength of the South Asian monsoon can also be linked to the Strange
Parallels Drought (1756-1768) affecting much of Southeast Asia and the Indian
subcontinent in the mid-18th Century. Large-scale climate anomalies across the
wider region during years with an anomalously strengthened/weakened South Asian
monsoon are discussed with implications for severe droughts prior to the instrumental
period.
Insights into the relative influences of Pacific and Indian Ocean variability for Asian
monsoon climate on interannual to decadal and longer timescales, as recorded in the MADA,
provide a useful tool for assessing long-term changes in the characteristics of Asian monsoon
droughts in the context of Indo-Pacific climate variability. |
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