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



Atmospheric Blocking and Greenland melt

by Victoria Lee, Robin S. Smith, Tony Payne

Atmospheric blocking occurs when near-stationary high-pressure systems divert westerly flow for a week or more. It can cause extreme regional weather such as heatwaves in summer and cold spells in winter. In this article we explore the connection between blocking over Greenland and enhanced surface melting of the ice sheet in UKESM1.ice N96 ORCA1 present-day run.  Read more…

First Analysis of ScenarioMIP Projections from UKESM1 in the Context of Global Warming Thresholds

by Ranjini Swaminathan, Colin Jones, Robert Parker, Douglas Kelley, Jeremy Walton

In this article, we analyse and present some early results for when UKESM1 ScenarioMIP ensemble members will exceed key global warming thresholds (GWTs). We have assessed the patterns of regional climate change simulated in UKESM1, centred on these “exceedance dates” to give a snapshot of how the future Earth System might look when we reach these GWTs. Read more…

3D visualization of CMIP6 data

by Jeremy Walton.

The UKESM1 earth system model has been used to run the climate experiments prescribed by the CMIP6 project, including a simulation of the historical period (1850-2014) and a range of projections (2015-2100) which explore ways in which the Earth’s climate could evolve in the future. We expect to upload around 5PB of data for CMIP6, so it is more important than ever to exploit our data and develop visual representations in 2D and 3D to communicate information to policymakers and the public. Read more…

Recent Events

UKESM – LTSM General Assembly, Online – 16-17 June 2020

The 2020 UKESM General Assembly went fully online for our two day meeting. Whilst we may have missed out on meeting face-to-face this year, it did mean that we had between 80 to over 100 participants in the sessions – from as far as New Zealand, Australia and South Korea.

Day 1 included: a review of the progress of the UKESM project over the past year (Colin Jones & UKESM team), the 2nd NERC Long Term Science Multi Centre (LTSM) programme (Rowan Sutton) and policy related science talks

  • Investigating abrupt, potentially irreversible changes in the Earth system. Tim Lenton
  • Allowable carbon budgets for meeting key policy targets. Chris Jones
  • The mitigation potential of non-CO2 Short Lived Climate Forcers and potential co-benefits for regional air quality. Fiona O’Connor
  • Assessing aggressive climate mitigation strategies. Cat Scott 

An international perspective on Earth system modelling was provided by Olivier Boucher (IPSL) and Jean-François Lamarque (NCAR/CESM). Day 1 was rounded off by a summary by Jane Mulcahy (UKESM).

Most of Day 2 was dedicated to short science talks related to UKESM developments or using the generated datasets in the Coupled Model Intercomparison Projects (CMIPs).

20 short talks were given by a mixture of the UKESM team, collaborators and researchers in other institutions. A full list is available at the link below.

Further details, slides and a link to recordings of all the sessions on YouTube can be found on our website: https://ukesm.ac.uk/ukesm-general-assembly-16-17-june-2020/

CMIP6 Analysis Seminars – Online in April and May 2020

Five online seminars were held over the 20, 21 April & 15 May involving 25 scientists presenting their work on the analysis of CMIP6 simulations. We were particularly pleased to involve a number of Early Career Scientists in the programme of talks. The full list of presentations and slides are available for each session at:



UKESM1 in the research literature

The Journal of Advances in Modeling Earth Systems has a special issue on: The UK Earth System Models for CMIP6. Recent updates to this issue include:

  • Andrews et al. 2020: Historical Simulations With HadGEM3-GC3.1 for CMIP6
  • Bodas-Salcedo et al. 2019: Strong dependence of Atmospheric Feedbacks on Mixed-Phase Microphysics and Aerosol-Cloud interactions in HadGEM3 (explains high ECS & cloud feedbacks in UKESM1)
  • Andrews et al. 2019: Forcings, Feedbacks and Climate Sensitivity in HadGEM3-GC3.1 and UKESM1

In Atmospheric Chemistry and Physics online journal:

  • Fiona O’Connor et al. 2019: Assessment of pre-industrial to present-day anthropogenic climate forcing in UKESM1

Papers coming soon:

  • Kuhlbrodt et al. 2020: Ocean heat uptake in the UK model historical simulations
  • Yool et al 2020: Evaluation of the ocean component of UKESM1 CMIP6 historical simulations
  • Kelley et al 2020: Evaluation of the land component of UKESM1 in CMIP6 historical simulations


July 2020 I’m A Scientist, Stay At Home

by Andrew Yool

Since 2010, “I’m A Scientist, Get Me Out Of Here” has run an annual fortnight of online outreach events in which school students from around the UK chat with scientists about anything and everything science. With the advent of lockdown across the UK in response to the COVID-19 pandemic, an expanded programme of “I’m A Scientist, Stay At Home” events has been running since May. The format for “I’m A Scientist” is primarily online chat sessions – sometimes themed, sometimes completely open – in which students and scientists come together to pose and answer questions. In addition, the website hosts “Ask A Scientist”, allowing questions to be posted for everyone in the community to answer.

Taking part in this summer’s events has been Andrew Yool, one of UKESM1’s marine biogeochemists. He joined the coding, environment and “Summer 2020” zones of the event, and has taken part in a number of chatroom sessions. In each of these, around 10-15 scientists took part in fast and furious conversations sparked by questions from up to 30 students. Typically these questions are posed by students at particular scientists (of whom, potted biographies are available), but many are open to @all for anyone to answer. Questions can be broken out into separate chat threads for scientists and students alike to follow-up on and dig deeper. As well as questions on particular science topics, many questions touch on why people became scientists, what it’s like to be a scientist day-to-day, and how students can make science their career.

During his time in the chatrooms so far, Andrew has been asked questions about how he models plankton in UKESM1, how the ocean’s carbon cycle works, and what nutrient cycles are. He has also fielded questions on topics as wide ranging as why cats eyes are reflective, why we produce toxic waste, and why hearing aids are not what animals need to understand human language. On the chatrooms, he remarked, “Although frenetic at times, the enthusiasm from the students is very infectious, and it’s a real buzz to be able to help students with their questions – I’d definitely recommend taking part to my colleagues”.

“I’m A Scientist, Stay At Home” continues to the end of July 2020.

Andrew Yool is a researcher at the National Oceanography Centre, Southampton.







United Kingdom Chemistry and Aerosol (UKCA) model – Community Survey

The United Kingdom Chemistry and Aerosol (UKCA) model is a widely used atmospheric composition model. UKCA is the composition model of choice in UKESM. The UKCA user community has grown significantly over time necessitating a more robust management structure. To respond to this need the UKCA Science Management Group (SMG) has been created. Currently, the SMG is drawing up a new strategy to guide science and development for the next few years. However, the SMG strongly feels that the forthcoming UKCA science and development strategy should reflect the interests and needs of the community rather than the opinions of its management alone. Therefore, the SMG needs to understand better those needs and priorities of the community. We have designed a community survey and we ask you all for your help. Please follow the link to the survey below or go to the UKCA website (https://www.ukca.ac.uk/wiki/index.php/UKCA) and follow the link on the landing page.

Link to the survey: https://docs.google.com/forms/d/e/1FAIpQLSe6fFb3lnSTyEXv5oxPFp3wTkvG8FI6duQYYWWvnaoMGdDrNA/viewform?usp=send_form

ESGF user feedback survey 2020 

The ESGF user feedback survey 2020 has been launched. This infrastructure-focused survey aims to collect feedback from a broad range of ESGF users, including the broad community of CMIP data users and stakeholders. The results of the survey will focus the development priorities for the next-generation ESGF software stack and website, along with the ESGF computing capabilities to be launched soon alongside the data.

This infrastructure-focused survey is being led by the Earth System Grid Federation (ESGF) in collaboration IS-ENES with the WCRP WGCM Infrastructure Panel to “take the temperature” of how CMIP data contributors, users, and stakeholders are working with ESGF to search, access and download data. We expect another science-focused survey led by the CMIP panel and focused on the possible design of CMIP7 will follow in a number of months.

The survey will take 10-15 minutes of your time, and is available at https://www.surveymonkey.com/r/3RZFPG7

We appreciate it if you can respond before Monday 20th August 2020.

We invite you to forward the details far and wide so that we can collate the most representative feedback for ESGF’s broad contributor and user communities.


Team News

Recent additions to the UKESM Core Group:

Stephen Pring joined the UKESM core group in February 2020 as a scientific software engineer. Prior to this Stephen worked in Dynamics Research at the Met Office between 2015-2019. During this time Stephen worked on developing the next-generation dynamical core called GungHo. Designed to be more scalable than the current dynamical core ENDGame within the UM, GungHo uses a cubed-sphere mesh rather than a latitude-longitude mesh to avoid singularities at the poles. Before this Stephen worked in Data Assimilation between 2010-2014, where Stephen worked on developing the ensemble-variational ensemble generation system which is now being used operationally at the Met Office for generating the forecast ensemble members.