Interaction/teleconnection between tropics and extra-tropics

The aim of this initiative is to evaluate the ability of the current state-of -the-art dynamical forecasting systems in representing the tropical-extratropical teleconnections. The analysis, based on observational and model data from several seasonal forecast systems, uses a common framework for a straightforward intercomparison. Tropical rainfall anomalies are used to represent the response to anomalous tropical atmospheric heat sources.

Participating members (so far): ECMWF (UK), Met Office (UK), Meteo France (France), NCEP (USA), CMC (MSC) (Canada), CMA/BCC (China), BOM (Canada)

Planned analysis:

Precipitation:

  • precipitation variability relationship across the tropical regions / SST-precipitation relationship;
  • the predictive skill of precipitation across the different tropical basins;

Covariance and Rossby wave source analysis:

  • the predictive skill of the NAO and PNA via tropical teleconnections

Precipitation analysis is almost completed

Data: The model data is taken from CHFP and EUROSIP archive

Expected outcome:

  • estimate the model accuracy in representing remote atmospheric responses originated in the tropics.
  • improved and more reliable seasonal forecast predictions for the extratropical regions

REFERENCES:

Kumar et al. 2013: “Understanding prediction skill of seasonal mean precipitation over the tropics” Journal of Climate Vol. 26 p.5674-5681

Manola et al 2013: “Drivers of North Atlantic Oscillation Events”, Tellus A, 65, 1-13.

Molteni et al. 2014: “Understanding and modelling extra-tropical teleconnections with the Indo-Pacific region during the northern “. Climate Dynamics. Ref.: Ms. No. CLDY-D-14-00256R2

Scaife et al. 2016: « Tropical rainfall, rossby waves and regional winter climate predictions». QJRMSVersion of Record online: 20 OCT 2016 | DOI: 10.1002/qj.2910