Browsing by Author "Khodri, M."

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    Hydroclimate variability of the northwestern Amazon Basin near the Andean foothills of Peru related to the South American Monsoon System during the last 1600 years
    (European Geosciences Union (EGU), 2014-11-19) Apaéstegui Campos, James Emiliano; Cruz, F. W.; Sifeddine, A.; Vuille, M.; Espinoza, Jhan Carlo; Guyot, J. L.; Khodri, M.; Strikis, N.; Santos, R. V.; Cheng, H.; Edwards, L.; Carvalho, E.; Santini, W.
    In this paper we explore a speleothem δ ¹⁸O record from Palestina cave, northwestern Peru, at a site on the eastern side of the Andes cordillera, in the upper Amazon Basin. The δ ¹⁸O record is interpreted as a proxy for South American Summer Monsoon (SASM) intensity and allows the reconstruction of its variability during the last 1600 years. Two periods of anomalous changes in the climate mean state corresponding to the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA) periods identified in the Northern Hemisphere are recognized in the record, in which decreased and increased SASM activity, respectively, have been documented. Variations in SASM activity between the MCA and the LIA seem to be larger over the northern part of the continent, suggesting a latitudinal dependence of the MCA footprint. Our results, based on time series, composite and wavelet analyses, suggest that the Atlantic Multidecadal Oscillation (AMO) plays an relevant role for SASM modulation on multidecadal scales (∼ 65 years), especially during dry periods such as the MCA. Composite analyses, applied to evaluate the influence of the AMO on the Palestina cave δ¹⁸O and other δ¹⁸O-derived SASM reconstructions, allow insight into the spatial footprints of the AMO over tropical South America and highlight differences between records during key studied periods. This work also reveals that replicating regional climate signals from different sites, and using different proxies is absolutely essential for a comprehensive understanding of past changes in SASM activity.
    Palabras clave:SpeleothemsHydrometeorologyClimate
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    ItemOpen Access
    Hydroclimate variability of the northwestern Amazon Basin near the Andean foothills of Peru related to the South American Monsoon System during the last 1600 years
    (European Geosciences Union (EGU), 2014) Apaéstegui Campos, James Emiliano; Cruz, F. W.; Sifeddine, A.; Vuille, M.; Espinoza, Jhan Carlo; Guyot, J. L.; Khodri, M.; Strikis, N.; Santos, R. V.; Cheng, H.; Edwards, L.; Carvalho, E.; Santini, W.
    In this paper we explore a speleothem δ¹⁸O record from Palestina Cave, North Eastern Peru, at a site on the eastern side of the Andes cordillera, upper Amazon Basin, interpreted as a proxy for South America Summer Monsoon (SASM) intensity. This record 5 allows reconstructing SASM activity with ∼ 5 yr time resolution over the last 1600 yr, spanning two major periods of climate variability: the Medieval Climate Anomaly (MCA; 900–1200 AD) and Little Ice Age (LIA 1400–1850 AD) recognized as periods of decrease and increase SASM activity respectively. Time series and wavelet analyses reveal decadal to multidecadal frequencies. Our results suggest that Atlantic Multi10 decadal Oscillation mode (AMO) plays an important role for SASM modulation on multidecadal scale (∼ 65 yr), especially over dry periods such as observed during MCA. Frequencies of 8 and 25 yr simultaneously with multidecadal signal (65 yr) are found over the LIA. and suggest that those modes could be related to North Atlantic Oscillation (NAO) and Interdecadal Pacific Oscillation mode (IPO). Comparison with other 15 South American Paleoprecipitation records shows that the Atlantic and Pacific decadal to multidecadal variability and their teleconnections play an important role in the intensity and the regional patterns of rainfall distribution during the last 1600 yr.
    Palabras clave:HydrometeorologyPaleoclimatologyAtmospheric precipitation