Origin of the moisture associated with extreme storms in South America

Advisors: Professor Joaquín Meza and Professor Álvaro Ossandón (UTFSM)

Motivation

Extreme events in South America depend on the moisture that the atmospheric circulation carries from the oceans and from other regions of the continent, such as the Amazon. Identifying the source regions of that moisture in each area helps explain the mechanisms behind extreme events and assess how they may respond to climate change. The group has already carried out this analysis in Chile; this thesis extends it to the continental scale.

Question: Where does the moisture associated with extreme storms in the different regions of South America come from?

What you will do

• Compile and quality-control historical precipitation records from stations in several South American countries.
• Identify the extreme storms in each region from those records.
• Compute Lagrangian back-trajectories of air parcels for each event with HYSPLIT (opens in a new tab), NOAA's model, driven by atmospheric reanalysis.
• Use changes in specific humidity along the trajectories to estimate where the parcels take up moisture, and link those source regions to each extreme event.
• Compare moisture sources across the regions of South America.

Requirements

Programming in Python or R (or the will to learn it) and reading in English.