Trends and oscillations in the Indian summer monsoon rainfall over the last two millennia


Contact
Manfred.Mudelsee [ at ] awi.de

Abstract

Observations show that summer rainfall over large parts of South Asia has declined over the past five to six decades. It remains unclear, however, whether this trend is due to natural variability or increased anthropogenic aerosol loading over South Asia. Here we use stable oxygen isotopes in speleothems from northern India to reconstruct variations in Indian monsoon rainfall over the last two millennia. We find that within the long-term context of our record, the current drying trend is not outside the envelope of monsoon’s oscillatory variability, albeit at the lower edge of this variance. Furthermore, the magnitude of multi-decadal oscillatory variability in monsoon rainfall inferred from our proxy record is comparable to model estimates of anthropogenic-forced trends of mean monsoon rainfall in the 21st century under various emission scenarios. Our results suggest that anthropogenicforced changes in monsoon rainfall will remain difficult to detect against a backdrop of large natural variability



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Peer revision
Scopus/ISI peer-reviewed
Publication Status
Published
Eprint ID
37403
Cite as
Sinha, A. , Kathayat, G. , Cheng, H. , Breitenbach, S. F. M. , Berkelhammer, M. , Mudelsee, M. , Biswas, J. and Edwards, R. L. (2015): Trends and oscillations in the Indian summer monsoon rainfall over the last two millennia , Nature Communications, 6 (6309), pp. 1-8 .


Share

Research Platforms
N/A

Campaigns


Actions
Edit Item Edit Item