ENSO Teleconnection Pattern Changes over the Southeastern United States under a Climate Change Scenario in CMIP5 Models

Ji-Hyun Oh,Steven D Cocke,D W Shin,Guillermo A Baigorria

doi:10.1155/2014/648197

Abstract

A strong teleconnection exists between the sea surface temperature (SST) over the tropical Pacific and the winter precipitation in the southeastern United States (SE US). This feature is adopted to validate the fidelity of Coupled Model Intercomparison Project Phase 5 (CMIP5) in this study. In addition, the authors examine whether the teleconnection pattern persists in the future under a global warming scenario. Generally, most of the eight selected models show a positive correlation between November SST over Niño 3 region and December–February (DJF) mean daily precipitation anomalies over the SE US, consistent with the observation. However, the models with poor realization of skewness of Niño indices fail to simulate the realistic teleconnection pattern in the historical simulation. In the Representative Concentration Pathways 8.5 (RCP8.5) run, all of the models maintain positive and slightly increased correlation patterns. It is noteworthy that the region with strong teleconnection pattern shifts northward in the future. Increased variance of winter precipitation due to the SST teleconnection is shown over Alabama and Georgia rather than over Florida under the RCP8.5 scenario in most of the models, differing from the historical run in which the precipitation in Florida is the most attributable to the eastern Pacific SST.

Highlights

In 2008, many climate-modeling groups in the world agreed to build a new set of coordinated climate model experiments
We inquire whether the current teleconnection characteristics between winter precipitation over the southeastern United States (SE US) and the tropical Pacific sea surface temperature (SST) will persist in the future under the global warming scenario simulated by current state-of-the-art climate models
We find out that most of the 8 models selected in this study show a positive correlation between the November Nino 3 SST and the DJF mean daily precipitation anomalies over the SE US, consistent with the observation

Summary

Introduction

In 2008, many climate-modeling groups in the world agreed to build a new set of coordinated climate model experiments. The Coupled Model Intercomparison Project Phase 5 (CMIP5) was planned to produce a standard set of simulations from state-of-the-art models to assess the fidelity of the models in simulating the recent past, to provide projections of future climate change, and to promote our understanding of mechanisms responsible for model differences [1]. Numerous studies have been conducted to validate the credibility of the newly launched CMIP5 data globally [2,3,4,5], regional assessments of the CMIP5 have rarely been carried out. It is crucial to narrow our viewpoint to a regional scale.

Methods

Results

Conclusion