Affiliation:
1. Centre for Earth Ocean and Atmospheric Sciences University of Hyderabad Hyderabad Telangana India
2. National Centre for Earth Science Studies Ministry of Earth Sciences Thiruvananthapuram Kerala India
3. Physical Science and Engineering, King Abdullah University of Science and Technology Thuwal Saudi Arabia
4. Indian Institute of Tropical Meteorology Ministry of Earth Sciences Pune Maharashtra India
5. Department of Atmospheric and Space Sciences Savitribai Phule Pune University Pune Maharashtra India
Abstract
AbstractEarlier proxy‐observational studies, and a sole modeling study, suggest that the Indian Ocean Dipole (IOD), an important global climate driver, exhibited multi‐scale temporal variability during the Last Millennium (LM; CE 0851–1849, with relatively high number of strong positive IOD events during the Little Ice Age (LIA; CE 1550–1749), and strong negative IOD events during the Medieval Warm Period (MWP; CE 1000–1199). Using nine model simulations from the PMIP3, we study the IOD variability during the LM after due validation of the simulated current day (CE 1850–2005) IOD variability. Majority of the models simulate relatively higher number of positive IOD events during the MWP, and negative IOD events in the LIA, commensurate with simulated background conditions. However, higher number of strong positive IOD events are simulated relative to the negative IODs during the LIA, in agreement with proxy‐observations, apparently owing to increased coupled feedback during positive IODs.
Publisher
American Geophysical Union (AGU)