Welcome to UK Earth System Model (UKESM) News from the Joint Weather and Climate Research Programme (JWCRP).

The UK Earth system modelling project is a joint venture between the Met Office and the Natural Environmental Research Council (NERC) to develop and apply a world-leading Earth System Model.

If you like to get in touch, please email us at ukesm@ncas.ac.uk



UKESM1 science configuration complete and CMIP6 simulations started

by Colin Jones.

In April 2018 we completed the scientific and technical development of UKESM1 and started a number of baseline simulations as part of the 6th Coupled Model Intercomparison Project (CMIP6). This newsletter outlines early results from UKESM1 covering the CMIP6 DECK and a number of historical simulations, as well as a range of more targeted experiments used to characterize the model’s fundamental behaviour. Read more…

First results from CMIP6 DECK and historical runs

by Alistair Sellar, Colin Jones, Chris Jones and Lee de Mora.

The UKESM1 DECK and historical runs are now in full swing and we have begun an initial analysis of first results. Early indications are that the model performs well, with a number of interesting features. In this article we present some analysis of multi-decadal ocean-atmosphere variability in the UKESM1 spin-up and piControl, some findings pertaining to carbon uptake in the 1% CO2, transient increase runs and finally, early results from the UKESM1 historical ensemble. Read more…

A first look at the atmosphere in UKESM1

by Colin Jones, Jane Mulcahy, Stephanie Woodward, Fiona O’Connor and Till Kuhlbrodt.

The core of the UKESM1 atmosphere is the GA7.1 version of the Unified Model Global Atmosphere. In addition to GA7.1, UKESM1 also includes the UKCA stratosphere-troposphere interactive chemistry scheme, which predicts a number of key atmospheric greenhouse gases, as well as the chemical oxidants that lead to formation of atmospheric aerosol. Furthermore, a number of aerosol and chemical emissions that, are time-invariant and based on observations in the physical model HadGEM3-GC3.1 are interactively predicted and coupled to other components of UKESM1, allowing a broader spectrum of Earth system interactions and feedbacks to be represented. Read more…

UKESM1 beneath the waves

by Andrew Yool, Julien Palmiéri, Lee de Mora, Till Kuhlbrodt and Colin Jones.

As it stores the majority of the excess heat and carbon dioxide associated with climate change (both ongoing and into the future), the World Ocean is a critical component of the Earth system – and therefore UKESM1. Any imbalances in how the ocean interacts with other components of the modelled Earth system can translate into discrepancies between the real climate we see, and the climate we simulate within UKESM1. Here we take a look at the dynamics, chemistry and biology going on below the ocean surface in UKESM1. Read more…

UKESM1 global carbon cycle and diagnosed historical fossil fuel emissions

by Andy Wiltshire and Chris Jones.

A key aspect of Earth System Models that distinguishes them from their Global Climate Model counterparts is the representation of biogeochemical processes. The most crucial to understanding climate change is the carbon cycle. Both the land and oceans currently act as sinks for anthropogenic CO2 from fossil fuel emissions and land use change. In fact, only around 50% of anthropogenic CO2 remains the atmosphere, the rest is taken up by the land and ocean, through plant growth (CO2 is a plant fertiliser) and dissolution into the oceans. The ability to accurately capture these processes is crucial for Earth System Models such as UKESM1. Read more…

The release and support of UKESM1

by Jeremy Walton, Alistair Sellar, Yongming Tang, Marc Stringer, Richard Hill, Julien Palmieri, Rich Ellis, Grenville Lister, Colin Jones.

Version 1 of the UK Earth System Model (UKESM1) has been in development for the past five years. Built as a joint venture by the Met Office Hadley Centre and the Natural Environment Research Council (NERC), UKESM1 consists of the HadGEM3-GC3.1 coupled physical climate model, plus additional components that model key biogeochemical, chemistry, aerosol and vegetation processes. Plans have been developed for the release of UKESM1 to the NERC research community. The model has already been ported to the shared MONSooN platform in order to aid collaboration between the Met Office and NERC, and will soon be made available on ARCHER, the UKRI national platform. As with other models, CMS, in collaboration with the UKESM core group, will provide front-line support for UKESM1 after its release later this year. Read more…


9-10 July 2018 – UKESM-LTSM project annual meeting, UK Met Office, Exeter:

This year, the LTSM project celebrates its annual meeting at the Met Office Headquarters in Exeter. The meeting will run for two full days. Day 1 will include a special session dedicated to the UKESM1 model release, plus a number of presentations on broader research occurring within the UKESM-LTSM, with invited speakers and posters from the contributing NERC centres. Day 2 will be centred around project business, specific break groups and future science plans (Download the meeting agenda with links to the meeting presentations here).


26 March 2018 – Data Sciences for Climate and the Environment – The Alan Turing Institute, London:

This one-day workshop was focused on how new tools being developed in data science can be applied to questions relating to climate and the environment in order to help address the challenges which our society is facing on a rapidly changing planet. Collectively, we are modelling and monitoring our planet better than ever as a result of sustained efforts from the climate modelling community and space agencies. Climate and weather models can now be run at finer spatial resolutions, enabling more realistic simulations of smaller scale processes (e.g. tropical cyclones in the atmosphere or eddies in the ocean) that can have severe impacts on our planet. At the same time there is a rapid growth in the number of satellites orbiting the Earth, with a significant fraction of these satellites dedicated to Earth Observation using a variety of sensors working at different electromagnetic frequencies. Our ability to store, process and efficiently share the vast amounts of data that are produced by the modelling and remote sensing communities is a pre-requisite for the effective functioning of these large research programmes.

The workshop attended by UKESM core group member Jeremy Walton featured five keynote speakers from the US and the UK who presented on their work on producing, processing, sharing and analysing climate data. Jeremy described climate modelling using UKESM1 and the UK efforts to produce, convert and manage climate model data for CMIP6. The workshop concluded with a panel dialogue between the speakers and members of the audience.

More information about the event can be found here.  The proceedings were filmed – see here for the videos of the talks, and panel session.

4-8 June 2018 – 4th International Symposium on The Effects of Climate Change on the World’s Oceans – Washington, USA:

Team member Andrew Yool recently attended the 4th International Symposium on The Effects of Climate Change on the World’s Oceans (4-8 June 2018), organised by Pacific ICES. Andrew presented work on size-structured benthic communities, and how these will potentially change into the future using scenarios of change provided by NEMO-MEDUSA (in a slightly earlier form to that used in UKESM1). In summary, these communities are entirely dependent on food imports from the near-surface plankton, so changes in the activity of the latter (especially in how material is exported downwards from it) are key. The benthic model used in this work is not currently coupled to UKESM1, but there are plans for the inclusion of this submodel as part of ESM LTSM development activities for MEDUSA.


Recent additions to the UKESM Core Group:

Ranjini Swaminathan, National Centre for Earth Observation (NCEO) – University of Reading: Ranjini joined the UKESM Core Group in April 2018 as part of the NCEO contribution to the UKESM project. She will be involved in the development of science based diagnostics integrating observational data sets for model evaluation. Prior to joining the UKESM team, Ranjini was a research staff member at the Climate Science Centre at Texas Tech University, USA and at the University of Auckland, New Zealand where she developed computational models and machine learning algorithms for various climate science projects. Ranjini has a Ph.D. in Computer Science from The University of Arizona.

Collaboration with European Earth System models: IPSL-ESM:

In May and June 2018, UKESM core group member Till Kuhlbrodt spent six weeks in Paris with the team that develops and runs IPSL-ESM. UKESM1 and IPSL-ESM use the same physical ocean model NEMO with the same spatial resolution eORCA1 (approximately 100 km), while all other components (sea-ice, atmosphere, biogeochemistry) are different. While Till has configured and analysed NEMO eORCA1 for UKESM1, the same task for IPSL-ESM is done by Julie Deshayes and Juliette Mignot.

Till, Julie and Juliette have started assessing how the respective ir NEMO eORCA1 configurations differ, and what impact these difference have on the simulated climate. In the completed CMIP6 simulations, it appears that in IPSL-CM6 (the physical climate model at the core of IPSL-ESM) the AMOC is weaker and more variable than in the UK models, while the Antarctic circumpolar current shows rather similar strength and variability. Several common publications are planned about the performance of NEMO eORCA1 in European Earth System models and on understanding differences in simulated large-scale ocean variability, and biogeochemistry.

Till’s visit at IPSL was funded by the NCAS Visiting Scientist Programme.