Is winter precipitation change over Europe underestimated in current climate projections?

• Main Authors: Eduardo Moreno-Chamarro, Louis-Philippe Caron, Pablo Ortega, Saskia Loosveldt Tomas, Malcolm J. Roberts
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2020
• Subjects: North Atlantic
• Online Access: https://doi.org/10.5281/zenodo.3952782

Model output,observational data, and scripts corresponding to the manuscript "Is winter precipitation change over Europe underestimated in current climate projections?" Abstract IPCC models project a likely increase in winter precipitation over northern Europe under a high-emission scenario. These projections, however, typically rely on relatively coarse ~100-km-resolution models that might misrepresent important processes driving precipitation, such as extratropical cyclone activity. Here, we show that a pioneering 50-km-atmosphere–1/12°-ocean global coupled model simulation projects a substantially larger increase in winter precipitation over northwestern Europe by mid-century than lower-resolution configurations. For this increase, both the highest ocean and atmosphere resolutions are essential: First, only the eddy-rich (1/12°) ocean projects a progressive northward shift and warming of the Gulf Stream. Second, only the 50-km atmosphere translates such warming into strengthened North Atlantic extratropical cyclone activity through enhanced diabatic heating and eddy-driven jet. Our results suggest that climate projections using traditional ~100-km-resolution models might underestimate the precipitation increase over Europe in winter and, consequently, the related potential risks.