Oslo joint seminar in atmospheric, ocean and climate science, Oct. 31

Title: The role of aerosols in the predictability at the subseasonal-to-seasonal scale

Speaker: Angela Benedetti, ECMWF

Speaker: Angela Benedetti, ECMWF

Abstract:

Recent years have seen the rise of global operational atmospheric composition models for several applications including climate monitoring, provision of boundary conditions for regional air quality forecasting, and energy sector applications, to mention a few. Typically
global forecasts are provided in the medium-range up to five days ahead.

Thanks to a series of EU-funded projects (GEMS, MACC, MACC-II, MACC-III), and now Copernicus, ECMWF has developed the capability to run its Integrated Forecast System (IFS) with atmospheric composition variables. The composition configuration is at the core of the Copernicus Atmospheric Service (CAMS) which provides operational 4D-Var analyses and forecasts of aerosols and reactive gases, as well as many other user-oriented products both at the European scale and at the global scale. 

This capability is now being exploited for applications other than atmospheric composition forecasting per se.  This is part of an effort to understand how increased complexity in the Earth System model can have beneficial effects on the prediction. Recent work has shown that the atmospheric constituents such as aerosols, ozone and other trace gases can
be important modulators of the radiative processes at the S2S scale. For example, the direct effect of aerosols may influence predictability via the MJO modulation of the
aerosol fields. In clear-sky, the cumulative aerosol forcing can modify the radiative balance of the atmospheric column and introduce temperature perturbations which depend on the dominant aerosol types and their optical properties.  Wind-emitted aerosols such as dust appear to be the main contributors. However, biomass burning aerosols may also play an important part, in particular for areas where extensive seasonal biomass burning takes place such as central Africa and Indonesia.

Several examples related to this effort will be presented. In particular, the experiments  
using the ECMWF’s coupled Ensemble Prediction System to investigate the role of aerosols in the predictability at the seasonal-to-subseasonal (S2S) will be discussed.  
Aerosol forecast fields at the weekly/monthly scales will also be presented and compared with corresponding analyses to assess their quality. 
 

What is the Joint Oslo Seminar (JOS):

Atmospheric and climate sciences have a stronghold in Oslo among the four institutions University of Oslo, the Meteorological Institute, CICERO and NILU. This joint seminar invites renowned international experts to contribute to an informal series of lectures, meant to create interaction with the Oslo atmospheric and climate science community on recent highlights and analysis in the field. All seminars will be held on Thursdays (Noon -1pm) and lunch (sandwiches) will be served on a “first-come-first-served”-basis.

Published Aug. 14, 2019 12:19 PM - Last modified Oct. 29, 2019 8:05 AM