Increase in the Asian Southwest Monsoon During the Past Four Centuries

Climate reconstructions reveal unprecedented warming in the past century; however, little is known about trends in aspects such as the monsoon. We reconstructed the monsoon winds for the past 1000 years using fossil Globigerina bulloides abundance in box cores from the Arabian Sea and found that monsoon wind strength increased during the past four centuries as the Northern Hemisphere warmed. We infer that the observed link between Eurasian snow cover and the southwest monsoon persists on a centennial scale. Alternatively, the forcing implicated in the warming trend (volcanic aerosols, solar output, and greenhouse gases) may directly affect the monsoon. Either interpretation is consistent with the hypothesis that the southwest monsoon strength will increase during the coming century as greenhouse gas concentrations continue to rise and northern latitudes continue to warm.

[1]  M. Altabet,et al.  The effect of millennial-scale changes in Arabian Sea denitrification on atmospheric CO2 , 2002, Nature.

[2]  Maurizio Fedi,et al.  Multiscale derivative analysis: A new tool to enhance detection of gravity source boundaries at various scales , 2002 .

[3]  D. Anderson.  Attenuation of millennial-scale events by bioturbation in marine sediments , 2001 .

[4]  Shaopeng Huang,et al.  Temperature trends over the past five centuries reconstructed from borehole temperatures , 2000, Nature.

[5]  M. Hughes,et al.  Northern hemisphere temperatures during the past millennium: Inferences, uncertainties, and limitations , 1999 .

[6]  G. Reichart,et al.  Temporal variability in the northern Arabian Sea oxygen minimum zone (OMZ) during the last 225,000 years , 1998 .

[7]  G. Ren.  Pollen evidence for increased summer rainfall in the medieval warm period at Maili, northeast China , 1998 .

[8]  S. Clemens,et al.  Nonstationary Phase of the Plio-Pleistocene Asian Monsoon , 1996, Science.

[9]  P. Roche.  Out, Damned CLIP! Out, I Say! , 1996, Science.

[10]  G. Jacoby,et al.  Mongolian Tree Rings and 20th-Century Warming , 1996, Science.

[11]  K. Lau,et al.  ON THE RELATIONSHIP BETWEEN EURASIAN SNOW COVER AND THE ASIAN SUMMER MONSOON , 1996 .

[12]  D. Garbe‐Schönberg,et al.  Teleconnections Between the Subtropical Monsoons and High-Latitude Climates During the Last Deglaciation , 1996, Science.

[13]  B. Malmgren,et al.  A High‐resolution record of Late Quaternary upwelling along the Oman Margin, Arabian Sea based on planktonic foraminifera , 1996 .

[14]  J. Overpeck,et al.  The southwest Indian Monsoon over the last 18 000 years , 1996 .

[15]  A. Zhisheng,et al.  Correlation between climate events in the North Atlantic and China during the last glaciation , 1995, Nature.

[16]  W. Prell,et al.  Climate-related variations in denitrification in the Arabian Sea from sediment 15N/14N ratios , 1995, Nature.

[17]  A. Munot,et al.  All-India monthly and seasonal rainfall series: 1871–1993 , 1994 .

[18]  G. Meehl,et al.  Coupled Land-Ocean-Atmosphere Processes and South Asian Monsoon Variability , 1994, Science.

[19]  D. Anderson,et al.  A 300 KYR Record of Upwelling Off Oman during the Late Quaternary: Evidence of the Asian Southwest Monsoon , 1993 .

[20]  C. V. Naidu,et al.  Spatial variations and trends in the Indian monsoon rainfall , 1992 .

[21]  Mojib Latif,et al.  The Effect of Eurasian Snow Cover on Regional and Global Climate Variations , 1989 .

[22]  Cohmap Members.  Climatic changes of the last 18,000 years: observations and model simulations. , 1988, Science.

[23]  J. Kutzbach,et al.  Milankovitch forcing of fluctuations in the level of tropical lakes from 18 to 0 kyr BP , 1985, Nature.

[24]  T. Goreau.  Frequency sensitivity of the deep-sea climatic record , 1980, Nature.

[25]  M. Stuiver,et al.  Modeling Atmospheric 14C Influences and 14C Ages of Marine Samples to 10,000 BC , 1993, Radiocarbon.