Chapter 66
Aerosol Intensive Optical Properties
in the NMMB-MONARCH
Vincenzo Obiso, Oriol Jorba, Carlos Pérez García-Pando
and Marco Pandolfi
Abstract The NMMB-MONARCH is a fully online integrated meteorologychemistry model for short- and mid-term Chemical Weather Forecasts (CWF) developed at the Barcelona Supercomputing Center (Earth Sciences). The meteorological
core is the Nonhydrostatic Multiscale Model on the B-grid (NMMB). The global
aerosol module includes five natural and anthropogenic species: mineral dust, sea
salt, organic matter, black carbon and sulfate. The full online coupling between the
aerosol module and the model radiation scheme (RRTMG) has been recently implemented. We present in this work a first evaluation of the aerosol intensive optical
properties required by the coupling mechanism: single scattering albedo (ω) and
asymmetry factor (g). New aerosol refractive indexes from recent literature have
also been tested. We found that the model performance improves when considering
a less absorbing mineral dust. Moreover, in anthropogenic areas a purely scattering organic matter and a higher real index for sulfate partially reduce the model
systematic biases.
66.1 Introduction
In literature very few studies report on model evaluations of intensive optical properties, even if these have been recognized to be crucial parameters controlling the
radiative impact of the aerosols [7]. From the few available studies it seems clear
that the performance of the state-of-the-art models is quite variable and in general
poor [7, 10]. This general context suggests that still large uncertainties affect the
aerosol microphysical and optical parameterizations and so that further investigation
is needed to better assess and constrain the uncertainty sources. In this work aerosol
optical properties for a period of 5 years (2012–2016) have been simulated over a
V. Obiso · O. Jorba (B) · C. P. García-Pando
Earth Sciences Department, Barcelona Supercomputing Center (BSC), Barcelona, Spain
e-mail: oriol.jorba@bsc.es
M. Pandolfi
Institute of Environmental Assessment and Water Research, (IDAEA-CSIC), Barcelona, Spain
© Springer Nature Switzerland AG 2020
C. Mensink et al. (eds.), Air Pollution Modeling and its Application XXVI,
Springer Proceedings in Complexity,
https://doi.org/10.1007/978-3-030-22055-6_66
413
Aerosol Intensive Optical Properties
in the NMMB-MONARCH
Vincenzo Obiso, Oriol Jorba, Carlos Pérez García-Pando
and Marco Pandolfi
Abstract The NMMB-MONARCH is a fully online integrated meteorologychemistry model for short- and mid-term Chemical Weather Forecasts (CWF) developed at the Barcelona Supercomputing Center (Earth Sciences). The meteorological
core is the Nonhydrostatic Multiscale Model on the B-grid (NMMB). The global
aerosol module includes five natural and anthropogenic species: mineral dust, sea
salt, organic matter, black carbon and sulfate. The full online coupling between the
aerosol module and the model radiation scheme (RRTMG) has been recently implemented. We present in this work a first evaluation of the aerosol intensive optical
properties required by the coupling mechanism: single scattering albedo (ω) and
asymmetry factor (g). New aerosol refractive indexes from recent literature have
also been tested. We found that the model performance improves when considering
a less absorbing mineral dust. Moreover, in anthropogenic areas a purely scattering organic matter and a higher real index for sulfate partially reduce the model
systematic biases.
66.1 Introduction
In literature very few studies report on model evaluations of intensive optical properties, even if these have been recognized to be crucial parameters controlling the
radiative impact of the aerosols [7]. From the few available studies it seems clear
that the performance of the state-of-the-art models is quite variable and in general
poor [7, 10]. This general context suggests that still large uncertainties affect the
aerosol microphysical and optical parameterizations and so that further investigation
is needed to better assess and constrain the uncertainty sources. In this work aerosol
optical properties for a period of 5 years (2012–2016) have been simulated over a
V. Obiso · O. Jorba (B) · C. P. García-Pando
Earth Sciences Department, Barcelona Supercomputing Center (BSC), Barcelona, Spain
e-mail: oriol.jorba@bsc.es
M. Pandolfi
Institute of Environmental Assessment and Water Research, (IDAEA-CSIC), Barcelona, Spain
© Springer Nature Switzerland AG 2020
C. Mensink et al. (eds.), Air Pollution Modeling and its Application XXVI,
Springer Proceedings in Complexity,
https://doi.org/10.1007/978-3-030-22055-6_66
413