Teleconnections over Brazil with an empirical-dynamical model of intermediate complexity

• Grant number: 17/02613-0
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• Start date: May 15, 2017
• End date: August 14, 2017
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Meteorology
• Principal Investigator: Tercio Ambrizzi
• Grantee: Tercio Ambrizzi
• Visiting researcher: Nicholas Hall
• Visiting researcher institution: Laboratoire d’Etudes en Géophysique et Océanographie Spatiales (LEGOS), France
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 08/58101-9 - Impact of the Southwestern Atlantic Ocean on South American climate for the 20th and 21st centuries, AP.PFPMCG.TEM

Abstract

A two-month visit is proposed for Prof. Nicholas Hall, University of Toulouse, France to initiate collaboration on the use of an empirical-dynamical model of intermediate complexity to address problems related to regional climate variability and global teleconnections. Based on data analysis and theoretical work, some recent hypotheses concerning the relationship between the regional climate over Brazil, the global tropics and the southern hemisphere mid-latitude circulation have been put forward. We propose to investigate these hypotheses further using a dynamical modelling approach. We will install this dynamical model at the Dept. of Atmospheric Sciences, USP and, in collaboration with students and staff from the department, use it to perform experiments designed to isolate the key elements in the chain of teleconnections which is thought to link Brazilian regional interannual and intraseasonal variability with both precursor and response signals around the world. We can use this modelling framework to examine the sensitivity to factors such as season and stationarity (basic state), nonlinearity (transient feedback) and possibly the effects of moist thermodynamics. We will also work towards a publication on contributing factors to the 2014 drought over Southeast Brazil. Prof. Hall will work on installing and developing the model, and explaining its principles of operation to interested collaborators at the IAG/USP. (AU)