Type
Text
Type
Dissertation
Advisor
Zhang, Minghua | Black, David E. Chang, Edmund K.M. Kim, Hyemi | McGee, David
Date
2016-12-01
Keywords
Low-Latitude Atlantic, Multidecadal Variability
Department
Department of Marine and Atmospheric Science
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/77769
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
Atlantic multidecadal variability (AMV) influences climate of Atlantic coastal continents, including the Atlantic hurricanes, European summer rainfall, Sahelian precipitation, and African dust. Identifying corresponding climate proxies and integrating them with modern instrumental and reanalysis records are important to understand it in the context of future changes caused by human activities. In this study, we used the high-resolution and marine-based Globigerina bulloides abundance data from Cariaco Basin, the 20th Century reanalysis data, as well as other paleoclimate records to investigate the spatial pattern and coherence of the AMV. We then evaluated the ability of climate models in simulating the AMV. From the analysis of modern instrument record, the variability of G. bulloides sediment abundance is found to have significant correlation with large-scale atmospheric and oceanic conditions in the North Atlantic during the past century. Enhanced abundance of Cariaco Basin G. bulloides is associated with cooler North Atlantic sea surface temperature (SST), higher Azores High pressure, stronger tropical North Atlantic easterly trade winds, and less Intertropical Convergence Zone (ITCZ) rainfall in the African Sahel. We propose that the AMV influences the variation of zonal wind and G. bulloides abundance through Azores High pressure. Consistent relationships are found from using different longer-term paleoclimate records at the multidecadal frequency. Globigerina bulloides sediment abundance is shown to negatively correlate with SST reconstruction at Eastern Tropical Atlantic and Puerto Rico at the same timescales, and positively correlate with a proxy of the multidecadal variabilities of the North Atlantic Oscillation (NAO). These results support that AMV exists prior to industrialization and its spatial pattern and coherence were similar in the pre-industry period to that in the 20th century. The ability of five CMIP5 (Coupled Model Intercomparison Project Phase 5) models in simulating the AMV are evaluated from their historical and past millennium simulations. It was found that two models can capture the AMV spatial pattern shown in the reanalysis data, and the MPI-ESM (Max Planck Institute Earth System Model) performs the best in modeling the North Atlantic sea surface temperature (SST) as well as the spatial pattern and coherence of the AMV. | 145 pages
Recommended Citation
Xiao, Tingyin, "Spatial Characteristics of the Low-Latitude Atlantic Multidecadal Variability during the Past Millennium and Evaluation of CMIP5 Model Simulations" (2016). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 3548.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/3548