Lecturer
Paolo Pezzutto
ISMAR-CNR, Venice, Italy
Abstract:
Two ensemble prediction systems (EPS) have been implemented operationally in the Mediterranean Sea. They are managed by the Italian Air Force Meteorological Service (CNMCA) and by the U.K. Meteorological Office.
The results have been intercompared and verified using an extensive dataset of wind and wave data from anemometer and meteo-oceanographic buoys, and from remotely sensed data (altimeter and scatterometer).
We have found relevant skill disparities between the two systems. One of the reasons can be the substantial difference in the formulation of the two meteorological models.
The UKMO wave EPS is based on a relatively coarse input, i.e. the wind fields of their global MOGREPS model with 32 km resolution. The CNMCA COSMO winds (7km resolution) operate in the full meso-scale region.
The consequence is that UKMO system wind input leads in general to an underestimate in the short fetch wave fields.
Nettuno resolves better the convective scale winds but, by doing that, it induces more uncertainty in short fetched events.
We observe significant differences in the behaviour at buoy and at altimeter locations for what concerns the relationships between ensemble spread (ES) and deterministic skill (STDE).
In case of altimeters, the wind spread-skill relationships appear to be directly transmitted to the wave height ones.
This is not the case at buoy locations. In general, the width of the Hs ensemble is not linearly related to the wind one.
Bologna, Italy - Bologna, Italy -
25 Feb 2015
Division Organized by
- CMCC - Euro-Mediterranean Center on Climate Change