The Open UniversitySkip to content
 

Building a traceable climate model hierarchy with multi-level emulators

Tran, Giang T.; Oliver, Kevin I. C.; Sóbester, András; Toal, David J. J.; Holden, Philip B.; Marsh, Robert; Challenor, Peter and Edwards, Neil R. (2016). Building a traceable climate model hierarchy with multi-level emulators. Advances in Statistical Climatology, Meteorology and Oceanography, 2(1) pp. 17–37.

Full text available as:
[img]
Preview
PDF (Version of Record) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (3MB) | Preview
URL: http://www.adv-stat-clim-meteorol-oceanogr.net/2/1...
DOI (Digital Object Identifier) Link: https://doi.org/10.5194/ascmo-2-17-2016
Google Scholar: Look up in Google Scholar

Abstract

To study climate change on multi-millennial timescales or to explore a model’s parameter space, efficient models with simplified and parameterised processes are required. However, the reduction in explicitly modelled processes can lead to underestimation of some atmospheric responses that are essential to the understanding of the climate system. While more complex general circulations are available and capable of simulating a more realistic climate, they are too computationally intensive for these purposes. In this work, we propose a multi-level Gaussian emulation technique to efficiently estimate the outputs of steady-state simulations of an expensive atmospheric model in response to changes in boundary forcing. The link between a computationally expensive atmospheric model, PLASIM (Planet Simulator), and a cheaper model, EMBM (energy–moisture balance model), is established through the common boundary condition specified by an ocean model, allowing for information to be propagated from one to the other. This technique allows PLASIM emulators to be built at a low cost. The method is first demonstrated by emulating a scalar summary quantity, the global mean surface air temperature. It is then employed to emulate the dimensionally reduced 2-D surface air temperature field. Even though the two atmospheric models chosen are structurally unrelated, Gaussian process emulators of PLASIM atmospheric variables are successfully constructed using EMBM as a fast approximation. With the extra information gained from the cheap model, the multi-level emulator of PLASIM’s 2-D surface air temperature field is built using only one-third the amount of expensive data required by the normal single-level technique. The constructed emulator is shown to capture 93.2% of the variance across the validation ensemble, with the averaged RMSE of 1.33 °C. Using the method proposed, quantities from PLASIM can be constructed and used to study the effects introduced by PLASIM’s atmosphere.

Item Type: Journal Item
Copyright Holders: 2016 The Authors
ISSN: 2364-3587
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Environment, Earth and Ecosystem Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Research Group: International Development & Inclusive Innovation
Item ID: 46195
Depositing User: Philip Holden
Date Deposited: 04 May 2016 10:30
Last Modified: 15 Jan 2019 06:31
URI: http://oro.open.ac.uk/id/eprint/46195
Share this page:

Metrics

Altmetrics from Altmetric

Citations from Dimensions

Download history for this item

These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.

Actions (login may be required)

Policies | Disclaimer

© The Open University   contact the OU