Difference between revisions of "UKCA Chemistry and Aerosol Tutorial 10"

Revision as of 10:46, 17 December 2014

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What you will learn in this Tutorial

In this tutorial you will learn about the Aerosol Optical Depth and how aerosol optical properties are diagnosed by RADAER GLOMAP-mode aerosol module and how it tracks different aerosol types within several size classes.

Task 10.1: Understand how the RADAER module diagoses aerosol optical properties from GLOMAP and provide direct radiative effects to the atmosphere model

Read section 13.2 (pages 41-44) of the UKCA UMDP.

Task 10.2: Derive Aerosol Optical Depth diagnostics from your UKCA model runs

As well as the providing the waveband-averaged scattering, extinction and asymetry parameters from GLOMAP, RADAER also diagnoses monochromatic Aerosol Optical Depth (AOD) for each of the GLOMAP modes.

One thing that is not included in the UMDP is the STASH section and item numbers for these GLOMAP Aerosol Optical Depth diagnostics.

UM-UKCA diagnoses the AOD from each of the GLOMAP modes as a separate STASH item.

All of the GLOMAP AOD diagnostics are contained with STASH section 2.

Although this section contains mainly diagnostics associated with long-wave radiation, it is where the CLASSIC Aerosol Optical Depth diagnostics are stored, and there were plenty of spare item numbers there, which have accomodated also the GLOMAP AOD diagnostics.

Section 2 items 300-305 contain the AOD for the Aitken-soluble, accumulation-soluble, coarse-soluble, Aitken-insoluble, accumulation-insoluble and coarse-soluble modes respectively.

Note that there is no nucleation mode AOD as those particles are too small to significant scatter or absorb solar or terrestrial radiation.

Diagnostics for the absorption AOD in these 6 modes can be requested via STASH section 2 items 240 to 245.

There are also separate "stratospheric AOD" diagnostics in section 2 items 254 to 259 which can also be requested to store the AOD in levels above the tropopause.

The dimensions for each of these STASH items is 2D global in longitude and latitude but there is also a third dimension containing 6 pseudo levels for the 6 monochromatic AODs stored by the model.

The standard settings for these are to store AOD at 0.38, 0.44, 0.55, 0.67, 0.87, 1.02 micron wavelengths although any wavelength can be set by modifying the values set in the RADAER fortran code.

As an example I have attached here a . pdf which compares the Aerosol Optical Depth (at 440nm) simulated in the UM-UKCA tutorial job comparing the jobs xjlub (top-left) and xjluc (top-right) which used the standard and 2-component OC configurations of GLOMAP.

Written by Graham Mann 2014

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 ==What you will learn in this Tutorial==
+In this tutorial you will learn about the Aerosol Optical Depth and how aerosol optical properties are diagnosed by RADAER GLOMAP-mode aerosol module and how it tracks different aerosol types within several size classes.
-In this tutorial you will learn about the GLOMAP-mode aerosol module and how it tracks different aerosol types within several size classes.  You will understand the standard configuration used in the UKCA jobs so far whereby the mass mixing ratios of sulphate, sea-salt, black carbon and organic matter in each mode are transported via separate tracers. GLOMAP-mode is an aerosol microphysics scheme and therefore, as well as transporting the mass of several components in the modes, the scheme also transports the number concentrations of particles in each mode.
+==Task 10.1: Understand how the RADAER module diagoses aerosol optical properties from GLOMAP and provide direct radiative effects to the atmosphere model==
-The lecture given on Monday morning already introduced the basic concepts behind the GLOMAP-mode aerosol microphysics scheme.
+Read section 13.2 (pages 41-44) of the  [http://www.ukca.ac.uk/wiki/images/b/b1/Umdp_084-umdp84.pdf UKCA UMDP].
-GLOMAP-mode has been coded to enable several supported "aerosol configurations" to be run within UM-UKCA using the same code-base.
+==Task 10.2: Derive Aerosol Optical Depth diagnostics from your UKCA model runs==
-Initially developed in the TOMCAT CTM environment (see Manktelow et al., 2007; Mann et al., 2010; Mann et al., 2012), the GLOMAP code then became the aerosol module for the UKCA sub-model of the UM (see Bellouin et al., 2013; Kipling et al., 2013; West et al., 2014; Mann et al., 2014; Dhomse et al., 2014).
+As well as the providing the waveband-averaged scattering, extinction and asymetry parameters from GLOMAP, RADAER also diagnoses monochromatic Aerosol Optical Depth (AOD) for each of the GLOMAP modes.
-GLOMAP is now also implemented into the ECMWF Integrated Forecasting System as part of the "Composition IFS" module (C-IFS) where it will be used in combination with data assimilation of satellite Aerosol Optical Depth to provide forecasts and re-analyses of atmospheric composition and boundary conditions for regional air quality models.
+One thing that is not included in the UMDP is the STASH section and item numbers for these GLOMAP Aerosol Optical Depth diagnostics.
-In section 12 of the UKCA UMDP, Table 18 shows the standard configuration for GLOMAP in all 3 of these modelling frameworks (TOMCAT, UM-UKCA and C-IFS-GLOMAP).
+UM-UKCA diagnoses the AOD from each of the GLOMAP modes as a separate STASH item.
-There the model runs with 7 modes each containing mixtures of up to 5 different aerosol components (sulphate, black carbon, organic matter, sea-salt and dust).
-In the configuration one has 7 number mixing ratios (one for each mode) and a total of 19 component mass mixing ratios (known as setup 8).
+All of the GLOMAP AOD diagnostics are contained with STASH section 2.
-The main currently supported configuration of GLOMAP within UM-UKCA has GLOMAP used in "5-mode configuration" (known as setup 2) covering only 4 of the above 5 components (sulphate, black carbon, organic matter and sea-salt) with dust handled via the existing 6-bin UM dust scheme.
+Although this section contains mainly diagnostics associated with long-wave radiation, it is where the CLASSIC Aerosol Optical Depth diagnostics are stored, and there were plenty of spare item numbers there, which have accomodated also the GLOMAP AOD diagnostics.
-The scheme can be reduced to cover just the sulphate and sea-salt components in 4 modes (known as setup 1) or extended to track two separate components for organic matter (OM) to track the mass of primary OM and secondary OM in each mode.
+Section 2 items 300-305 contain the AOD for the Aitken-soluble, accumulation-soluble, coarse-soluble, Aitken-insoluble, accumulation-insoluble and coarse-soluble modes respectively.
-Section 12.2 of the UMDP has a more detailed explaination of these components with Table 19 showing how these 4 different configurations map onto the model tracers.
+Note that there is no nucleation mode AOD as those particles are too small to significant scatter or absorb solar or terrestrial radiation.
-In this task you will take a copy of the standard UKCA job (which uses setup 2, MS2) and change it to use GLOMAP-mode "setup 4 (MS4) to track two separate organic matter (OM) components rather than the usual 1. With the 2-component OC configuration, the model tracks primary (emitted) organic carbon in the and secondary organic matter (formed following oxidation in the atmosphere) separately.
+Diagnostics for the absorption AOD in these 6 modes can be requested via STASH section 2 items 240 to 245.
-==Task 10.1: Understand how the GLOMAP aerosol module tracks aerosol species and modes==
+There are also separate "stratospheric AOD" diagnostics in section 2 items 254 to 259 which can also be requested to store the AOD in levels above the tropopause.
-<span style="color:black">'''TASK 10.1:''' Read section 12 (page 32) of the  [[Documentation|v8.4 UM Documentation Paper]] and refer to Tables 18, 19 and 20 on pages 33, 34 and 35.
+The dimensions for each of these STASH items is 2D global in longitude and latitude but there is also a third dimension containing 6 pseudo levels for the 6 monochromatic AODs stored by the model.
-==Task 10.2: Run a copy of the standard UKCA job which tracks two OC components in the GLOMAP modes==
+The standard settings for these are to store AOD at 0.38, 0.44, 0.55, 0.67, 0.87, 1.02 micron wavelengths although any wavelength can be set by modifying the values set in the RADAER fortran code.
-Copy your copy of the standard UKCA tutorial job (xjrna) from the UMUI and change the settings from the default UM-UKCA configuration for GLOMAP (setup 2) to instead use the 2-component OM configuration (setup 4).
+As an example I have attached here a .{{pdf|Idl_aodtracers_xjlub_vs_xjluc.pdf|pdf}} which compares the Aerosol Optical Depth (at 440nm) simulated in the UM-UKCA tutorial job comparing the jobs xjlub (top-left) and xjluc (top-right) which used the standard and 2-component OC configurations of GLOMAP.
-To run the 2-component GLOMAP configuration, you will also need to add in a branch to apply a slight change to the routine ukca_radaer_init.
-This extra branch is needed because the code-base at v8.4 was missing one of the necessary "setup files" to support GLOMAP setup 4.
-==Task 10.3 Examine the simulated total organic carbon in the original and two-cpt OC configurations==
-Once your standard and 2-component OC UM-UKCA jobs have completed you can plot up the output.
-We recommend you use xconv for this task although you may prefer to use IDL.----
-In these xjlub and xjluc jobs additionally daily-mean fields have been requested from STASH.
-Included in the extra STASH requests are the mass mixing ratios of OC (the standard organic component) and SO (the 2nd organic component) in each mode.
-The OC mmrs are STASH section 34, items 126 (nucleation mode), 106 (Aitken-soluble), 110 (accumn-soluble), 116 (coarse-soluble) and 121 (Aitken-insoluble).
-The SO mmrs are STASH section 34, items 128 (nucleation mode), 129 (Aitken-soluble), 130 (accumn-soluble), 131 (coarse-soluble).
-These STASH item numbers and the details of the standard and 2-component GLOMAP configurations can be found in the UKCA UMDP section 12 Tables 19 and 20.
-Note that there is no SO in the Aitken-insoluble mode as this contains only primary carbonaceous particles.
-Any SO or OC condensing onto the particles in the insoluble modes is immediately transferred over to the corresponding soluble mode following the "condensation-ageing" approach used by the model.  This OC or SO condensing onto the insoluble particles is a kind of "coating" for the particles making the particles hygroscopic/soluble.
-The mmr of the gas phase species MONOTER and SEC_ORG (STASH section 34, items 91 and 92) are also requested.
-As an example I have attached here a .{{pdf|Idl_orgtracers_xjlub_vs_xjluc.pdf|pdf}} which compares surface fields between xjlub (top-left) and xjluc (top-right).
-Included in these plots are the "total POM mmr" which is the total particulate organic matter (POM) summing up the mass of OC and SO in each mode.
-There also are pages showing comparisons of "total POM1 mmr" and "total POM2 mmr" which are the sum of the 1st and 2nd organic component over all the modes.
-You can see from the example that the "total POM2 mmr" in xjlub is zero everywhere.
-That's because in this job GLOMAP has the standard configuration with just one organic component.
-By contrast the "total POM2 mmr" for xjluc has considerable concentrations in vegetated continental regions.
-In this "I_MODE_SETUP=4" configuration, the "SEC_ORG" species (which contains the secondary organics from monoterpene oxidation) condenses into the "SO" component, whereas in xjlub SEC_ORG condenses into the "OC" component.
-This task illustrates how one can separate out the aerosol mass from different sources and track them separately via a different aerosol component.
-One could also introduce a 2nd gas phase species like "SEC_ORG" to track different types of SOA.
-For example one could configure the model so that such a 2nd "SEC_ORG2" species held semi-volatile oxidised organic species with very low volatile oxidised organics held in the usual "SEC_ORG" species.
 ''Written by [[User:Gmann | Graham Mann]] 2014''