UKCA Chemistry and Aerosol Tutorial 12

Back to UKCA Chemistry and Aerosol Tutorials

What you will learn in this Tutorial

In this tutorial you will learn about how to quantify the radiative effects of aerosol simulated by GLOMAP-mode in UM-UKCA.

In the first task you will update your copy of the UKCA tutorial job to request radiative fluxes allowing the radiative flux perturbation (or effective radiative forcing) to be diagnosed based on difference in the fluxes between a pair of UM-UKCA jobs with some difference (e.g. pre-industrial and present-day emissions jobs).

The second task involves configuring a copy of the UKCA tutorial job to run in double-call configuration whereby the aerosol radiative effects can be diagnosed at each radiation timestep.

Task 12.1: Update your copy of the UKCA tutorial job to diagnose Top Of the Atmosphere (TOA) radiative fluxes

In this task you will add STASH requests for SW and LW outgoing radiative fluxes at the top of the atmosphere to enable the radiative forcing from a particular change to be diagnosed.

The user should note however that to illustrate the task we are adding these requests to the UKCA tutorial job which is just a 1-day simulation.

One would need to average the flux-difference between the pair of simulations over an appropriate timescale (e.g. multi-annual monthly-means) or run with nudging to re-analysed meterology, in order to diagnose an effective radiative forcing.

Add daily-mean STASH requests for section 1 item 208 (all-sky outgoing short wave flux at the top-of-the-atmosphere) and section 2 item 205 (all-sky outgoing long wave flux at the top-of-the-atmosphere).

Task 12.2 Configure the UKCA tutorial job to run as a double-call job diagnosing aerosol radiative effects

Copy your copy of the standard UKCA tutorial job (xkvxe) 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).

To run the 2-component GLOMAP configuration, you will need to change the hand-edits in the UMUI to specify that you wish to run the model with additional aerosol tracers switched on.

First, open the hand-edits panel in the UMUI and find the line specifying to use the hand-edit

  ~mdalvi/umui_jobs/hand_edits/vn8.4/config_plume_scav_on_st.ed

Written by Graham Mann 2014