Review

Overview

Teaching: min
Exercises: min

Questions

• What have we learned so far?

• Where are we going?

Objectives

Midway through the semester is a good time to pause and review what we have learned so far and what we have left.

What have we learned so far?

• Some Unix commands
• How to use JupyterLab
• Reading and plotting Climate Model Output
• An overview of Atmospheric Models
• How to run CESM in fully coupled mode (B compset)
• How to modify the CESM to change how long to run, what to output and how often
• How to understand and postprocess CESM output
• How to run diagnostics packages for CESM
• Some advanced Python functions – groupby
• How to setup and run the Atmosphere and Land components of CESM with DOCN (F Compset)
• How to troubleshoot our model runs

Where are we going?

• Overview of Ocean and Ice Modeling
• How to run the Ocean and and Ice components of CESM with DATM
• How to change model code
• How to perform Intervention or Idealized experiments
• Reduced complexity models, why use them? how to run them?
• How to run an Initialized Prediction Experiment (Forecast)
• Regional Modeling
• Land and Land Ice
• Your projects!

Atmospheric Modeling

1. Dynamics (Equations of motion) Assumptions: hydrostatic Linearize, discretize, solve numerically Predict: thickness(w),u,v,q,T

2. Physics (Sub grid-scale Parameterized)
   • Clouds
   • Radiation
   • Convection
   • Microphysics
   • Boundary layer
   • Fluxes
   • Gravity waves
3. Boundary Forcing Information exchnaged with or prescried by other components of the climate system (e.g. soil moisture, sea surface temperature)

CESM Quickstart

A review of our CESM quickstart procedure

Create a newcase (this script is located in CIMEROOT/scripts)

./create_newcase --case CASEROOT --res RESOLUTION --compset COMPSET --project UGMU0032

Setup the case (run from your case directory)

./case.setup

Make your changes to the namelists, .xml files, and/or source codes

• Use xmlchange for .xml files
• Use user_nl_xxx for namelist changes
• Use SourceMods/src.xxx for code changes (we will talk about this today)

Build the case

qcmd -- ./case.build

Submit the run

./case.submit

CESM Compsets we have used so far

• B all components are active (fully coupled)
• F atmosphere and land are active; ocean and ice are inactive (data)

Today we will work with

• G ocean and ice are active; atmosphere and land are inactive (data)

Key Points