WP4: Future Climate Change

In LINC we will use the huge CMIP5 data base together with stand-alone atmospheric GCMs to 
study mechanisms of atmospheric teleconnection and climate variability on inter-annual to inter-decadal time scales. The intercomparison among various state-of-the-art models used for climate projections will i) allow determining the skill of the models in representing the characteristics of observed variability and ii) allow to study the mechanisms responsible for the processes. The intercomparison among various models will be done using standard linear multivariate statistical methodologies, like Empirical Orthogonal Functions, Singular Value Decomposition, etc, as well as using more advanced techniques of network theory, such as network characterization techniques (betweeness centrality, etc, which provides coupling between WP4 and WP1) and the concept of interacting networks applied to various climatological fields (such as temperatures and pressures, which provides coupling between WP4 and WP2). A posterior analysis will determine the potential changes in variability and teleconnections in the near future under scenarios of anthropogenic forcing. We will pay particular attention to the sensitivity of the climate networks and atmospheric teleconnections in the southern hemisphere,and specifically focus on the teleconnections from the tropical oceans to Southeastern South America because this is one of the main regions that is affected by the tropical Pacific and thus presents relatively high potential predictability. In the LINC network partner UR has expertise in 
this region that has a strong El Niño signal, that is transmitted through a variety of teleconnections that involve an extratropical path as well as tropical connections in upper and lower levels of the atmosphere. These connections have changed through the 20th century as El Niño suffered interdecadal modulations. Future changes in the teleconnections associated to changes in the position of the atmospheric jet streams due to a broadening of the tropical region or in the evolution of El Niño will likely alter this teleconnections, affecting the weather and climate. 
Specific objectives of WP4 are: 

1) improving the present understanding of atmospheric teleconnection processes by employing as a framework complex network theory and analysis;

2) evaluate how state-of-the-art climate models used for climate projections (CMIP5) represent the main teleconnections and global patterns of variability; 

3) quantify how these patterns will change in the near future due both to inter-decadal natural variability and anthropogenic forcing and

4) quantify how the mean climate and the extreme events will change in the near future and, possibly, provide uncertainty estimates for the next decades.