Influence of internal climate variability on Indian Ocean Dipole properties

Ng, Benjamin and Cai, Wenju and Cowan, Tim and Bi, Daohua (2018) Influence of internal climate variability on Indian Ocean Dipole properties. Scientific Reports, 8 (1):13500. pp. 1-8.

[img]
Preview
Text (Published Version)
Ng_Cai_Cowan_Bi_PV.pdf
Available under License Creative Commons Attribution 4.0.

Download (2MB) | Preview

Abstract

The Indian Ocean Dipole (IOD) is the dominant mode of interannual variability over the tropical Indian Ocean (IO) and its future changes are projected to impact the climate and weather of Australia, East Africa, and Indonesia. Understanding the response of the IOD to a warmer climate has been largely limited to studies of individual coupled general circulation models or multi-model ensembles. This has provided valuable insight into the IOD’s projected response to increasing greenhouse gases but has limitations in accounting for the role of internal climate variability. Using the Community Earth System Model Large Ensemble (CESM-LE), the IOD is examined in thirty-five present-day and future simulations to determine how internal variability influences properties of the IOD and their response to a warmer climate. Despite small perturbations in the initial conditions as the only difference between ensemble members, significant relationships between the mean state of the IO and the IOD arise, leading to a spread in the projected IOD responses to increasing greenhouse gases. This is driven by the positive Bjerknes feedback, where small differences in mean thermocline depth, which are caused by internal climate variability, generate significant variations in IOD amplitude, skewness, and the climatological zonal sea surface temperature gradient.


Statistics for USQ ePrint 35674
Statistics for this ePrint Item
Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Faculty/School / Institute/Centre: Current - Institute for Life Sciences and the Environment - Centre for Applied Climate Sciences (1 Aug 2018 -)
Faculty/School / Institute/Centre: Current - Institute for Life Sciences and the Environment - Centre for Applied Climate Sciences (1 Aug 2018 -)
Date Deposited: 01 Feb 2019 00:27
Last Modified: 24 May 2021 03:37
Uncontrolled Keywords: Indian Ocean Dipole; climate; impact
Fields of Research (2008): 04 Earth Sciences > 0401 Atmospheric Sciences > 040104 Climate Change Processes
04 Earth Sciences > 0401 Atmospheric Sciences > 040102 Atmospheric Dynamics
Socio-Economic Objectives (2008): D Environment > 96 Environment > 9603 Climate and Climate Change > 960303 Climate Change Models
Identification Number or DOI: https://doi.org/10.1038/s41598-018-31842-3
URI: http://eprints.usq.edu.au/id/eprint/35674

Actions (login required)

View Item Archive Repository Staff Only