Testing the NZESM through a single vertical column

Developing capacity in process assessment and improvement in NZESM through the use of the single column version of the model

Bodeker Scientific Contacts
Jordis Tradowsky

Funding Programme
Deep South National Science Challenge

Duration
2017 - 2018

Background

The New Zealand Earth System Model (NZESM) is a powerful tool for simulating the global climate system with a focus on the “Deep South”, i.e. the area around Aotearoa New Zealand, the Southern Ocean and Antarctica. However, its complexity can make it difficult to assess how well NZESM represents some physical processes occurring in the real world. The single column version of NZESM reduces this complexity and runs 22,000 times faster than the full model, thus allowing easier validation of different processes included within the NZESM. 

Research Aims

The project’s primary aim was to show how the single column model can be used to calculate surface and top-of-the-atmosphere radiances from vertical profile measurements of temperature, pressure, water vapour and ozone. The initial focus was on measurements from Scott Base (including Arrival Heights) and the AWARE (Atmospheric Radiation Measurement, West Antarctic Radiation Experiment) campaign at McMurdo. This project contributes to the Deep South Challenge mission by developing an independent and cost-effective means to assess and validate the physical processes in NZESM essential for simulating the climate of the Deep South.

One of the key outputs from this project was a software tool to create the input datasets required to run the model.  We call this the Single-column model Namelist Auto-Generator (SNAG). The code is available on GitHub here

A user-friendly guide to the Single Column version of the NZESM and the report is available to collaborators within the Unified Model Partnership on request to greg@bodekerscientific.com