EPOCASA: Enhancing seasonal-to-decadal Prediction Of Climate for the North Atlantic Sector and Arctic

EPOCASA will develop the first seasonal-to-decadal climate prediction capability in Norway, paving the way for operational climate prediction that will be of direct benefit to Norwegian society and economy.

Objectives

 The primary objective of EPOCASA is to develop a dynamical climate prediction system to assess predictability on seasonal-to-decadal timescales in the North Atlantic Sector and the Arctic.

Secondary goals are as follows:

- Improve understanding of key mechanisms for predictability leading to better prediction model

- Reduce uncertainties in future prediction (not only scenario)

- better quantification of internal and external variability during the historic record through constrained predictions, and predictability arising

- To carry out methodological development for the purpose of seasonal-to-decadal prediction

Project Summary

 During the last decade global surface temperatures rose less rapidly than in the preceding decades. The northern hemisphere saw a spate of harsh winters, exemplified by the last one with extremely cold temperatures and high snowfalls across Europe and eastern North America, and one of the driest March in Western Norway since reliable observations started around 1900. At the same time the Arctic experienced extreme warming and accelerated sea ice loss, culminating in the record-low of September 2012. While anthropogenic global warming may explain much of the recent changes, the northern hemisphere climate fluctuates strongly on timescales of several decades.

 EPOCASA aims to assess the extent to which these changes are predictable, by developing and applying a dynamical climate prediction system, focusing on the North Atlantic Sector and Arctic. EPOCASA is motivated by several recent advances: the demonstration that subpolar North Atlantic sea surface temperature (SST) are predictable on seasonal-to-decadal timescales, with observed links to the Nordic Seas and Arctic; potential role of stratosphere-troposphere interactions in the atmospheric response to tropical and extra-tropical SST, sea ice, and snow cover variations; as well as the need to reduce model systematic error and develop more advanced initialisation techniques. We will analyse observations and perform extensive model simulations to assess the potential of these factors to enhance climate prediction in the region.

 The EPOCASA prediction system couples an advanced data assimilation method (the Ensemble Kalman Filter) to the current version of the Norwegian Earth System Model, building upon developments initiated at the Center for Climate Dynamics at the Bjerknes Center. It will be first seasonal-to-decadal climate prediction capability in Norway, paving the way for operational climate prediction that will be of direct benefit to Norwegian Society and Economy.

Project Details
Acronym: 
EPOCASA
Funding Agency: 
Centre for Climate Dynamics - Research Council of Norway
NERSC Principal Investigator: 
Francois Counillon
Coordinating Institute: 
GFI, UIB
Project Status: 
Ongoing