PRIMAVERA

PRIMAVERA aims to develop a new generation of advanced and well-evaluated high-resolution global climate models, capable of simulating and predicting regional climate with unprecedented fidelity, for the benefit of governments, business and society in general.

Project Objectives

Advanced, high-fidelity models

The concept of model fidelity, the accuracy with which a numerical simulation captures the behaviour of the real world, is central to PRIMAVERA, and its foundations are in process understanding. It is clear that many of the most pressing questions about regional climate change urgently require advances in process simulation. For example, to what extent are recent heat waves, floods and droughts in Europe attributable to natural variability or human influences on the global climate system? How will the risk of such high impact events change over the next few decades and beyond? The extent to which it is possible to provide robust answers to these questions relies fundamentally on the fidelity of the climate models that are used to address them. However, fidelity is insufficient in itself: we must be able to  justify why a particular model produces a particular prediction at the process level.

Climate processes and high-resolution Global Climate Models (GCMs)

Many years of experience, first in numerical weather prediction and, equally albeit only recently, in climate simulation, have demonstrated that advances in the explicit simulation of key processes are essential to achieving sustained progress and to provide robust answers. High-resolution has been identified as one essential element of the development of GCMs to reproduce key climate processes with higher fidelity than conventional GCMs, thus enabling detailed process understanding.

ECMWF's contribution to the project

The ECMWF contribution to PRIMAVERA covers four main areas of research:

• Investigate the impact of horizontal resolution in the atmosphere and ocean models on the simulation of dynamical processes such as weather regimes, tropical cyclones, heat transport by ocean gyres and the Meridional Overturning Circulation  in the Atlantic (Work package 2).
• Improve the simulation of sea-ice variability by moving to a multi-category sea-ice model and testing the sensitivity to the representation of sea-ice albedo, snow over ice, melt ponds, etc. (Work package 3)
• Explore the characteristic of the atmospheric model climate and variability at a resolution high enough (5 km) to possibly permit an explicit simulation of convection (Work package 4)
• Investigate the impact on European climate variability of decadal-scale variations in Atlantic and Pacific SST (Atlantic Multi-decadal Oscillation and IPV), Arctic sea-ice cover and Eurasian snow cover (Work package 5)

More details can be found on the main project website