Operational Dust Prediction - Mineral Dust: A Key Player in the Earth System - page 228

Further information regarding the model characteristics such as horizontal and
vertical resolution and dust emission and deposition parameterisations is provided
in Tables 10.2 and 10.3 together with references for each model.

10.2.1 Global Models

ECMWF/MACC Aerosol Prediction System

Starting in 2008, ECMWF has been providing daily aerosol forecasts including dust
as part of the EU-funded projects GEMS, MACC and MACC-II (see Table 10.1
for acronyms). All data are publicly available online at http://www.copernicus-
atmosphere.eu . A detailed description of the ECMWF forecast and analysis model
including aerosol processes is given in Morcrette et al. ( 2009 ) and Benedetti et al.
( 2009 ). The initial package of ECMWF physical parameterisations dedicated to
aerosol processes mainly follows the aerosol treatment in the LOA/LMD-Z model
(Boucher et al. 2002 ; Reddy et al. 2005 ). Five types of tropospheric aerosols
are considered: sea salt, dust, organic and black carbon and sulphate aerosols.
Prognostic aerosols of natural origin, such as mineral dust, are described using
three size bins. Emissions of dust depend on the 10 m wind, the soil moisture,
the UV-visible component of the surface albedo and the fraction of land covered
by vegetation when the surface is snow-free. A correction to the 10 m wind to
account for gustiness is also included (Morcrette et al. 2008 ). MODIS AOD data
are routinely assimilated in a 4D-Var framework. The global modelling system of
MACC-II is also used to provide the boundary conditions for an ensemble of more
detailed regional air quality models that are used to zoom in on the European domain
and produce 4-day forecasts of air quality.

FNMOC Navy Aerosol Analysis and Prediction System

Based on the Danish Eulerian Hemispheric Model (Christensen 1997 ; Westphal
et al. 2009 ), NAAPS is an offline chemical transport model currently running with
single-size bin dust, smoke, sulphate and sea salt at 1/3 1/3 ı and 30 levels driven

by the 0.5 ı Navy Operational Global Atmospheric Prediction System (NOGAPS;
Hogan and Rosmond 1991 ). Operational NAAPS has MODIS data assimilation via
a 2D-Var framework (Zhang et al. 2008 ), with 3D-Var and ensemble Kalman filter
(EnKF) systems in development (e.g. Zhang et al. 2011 ). Next generation models,
such as an ensemble version of NAAPS run from the ensemble NOGAPS forecast,
are run quasi-operationally NRL at 1 ı resolution. Dust emission in NAAPS is based
on modelled friction velocity to the fourth power coupled to a source map which was
empirically derived from TOMS Aerosol Index products. A transition is in place to
adopt the recently expanded 1 km high-resolution database of Walker et al. ( 2009 ).
Data products with verification tools can be found at http://www.nrlmry.navy.mil/
aerosol/ with data archives at http://www.usgodae.org/ .