International activities

International Surface Temperature Initiative

I am the chair of the International Surface Temperature Initiative (ISTI) which consists of an interdisciplinary effort to improve our understanding of historical climate change through the creation of a suite of improved Land Surface Air Temperature products to meet science needs and societal expectations in the era of climate services. The initiative has four principal aims:

  • Improving the completeness and provenance of available basic data holdings
  • Promoting the development of novel techniques of homogenization to the basic data holdings
  • Benchmarking the performance of candidate techniques of homogenization against synthetically produced analogs to the real world holdings
  • Provision of products, tools, and guidance to end-users

I maintain both the website and the blog. On twitter look for hashtag #ISTI (warning there are other uses of this tag!).

Through my role in ISTI I have also been on the scientific steering committee of the Earthtemp Initiative which aims to bring together disparate research communities looking at surface temperature changes.

From 2015 I am also on the scientific advisory panel of a new Horizon 2020 project EUSTACE, led by the UK Met Office. This aims to merge in-situ and satellite records to produce long-term estimates of daily surface temperature changes across the globe.

GCOS Reference Upper Air Network

I am co-chair of the GCOS Working Group on the Global Climate Observing System Reference Upper Air Network (GRUAN). The GRUAN network aims to instigate and maintain on a multidecadal basis a high quality reference network of traceable and comparable measurement capabilities at a subset of global locations in support of monitoring, characterising broader aspects of the global observing system (including satellites) and process understanding.


Since 2016 I have been a member of the GCOS Atmospheric Observations Panel for Climate.

Since 2017 I have been a member of task teams associated with a surface reference network and the future of the GCOS Upper Air Network.


I was the project lead on the European Commission Horizon 2020 program project GAIA-CLIM 2015-2018. The project aimed to improve our capability to use ground-based and sub-orbital measurements to characterise satellite measurements. It was a large project with 18 partners and a budget of 6 million euros (minus a few cents).

GAIA-CLIM has a sister project that aims to improve metrological characterisation of satellite measurements, FIDUCEO. To ensure that synergies are realised I sit on its advisory panel under a reciprocal arrangement.

Global Land and Marine Observations Database

This is a new Copernicus Climate Change Service contract bring together Maynooth University, the National Oceanography Centre, Met Office, Science and Technology Facilities Council and NOAA's National Centers for Environmental Information. It shall run for 2017-2021. A link to the project website will be added when available.


In Spring 2014 the BIPM instigated a task group on the environment under the Consultative Committee on Thermometry. In summer of 2017 this was converted to a Working Group. I am a co-opted member on this team.

Commission for Climatology

I am chair of the group of rapporteurs on climate observational issues under OPACE 1.

Citizens Assembly

I have sat on the Expert Advisory Group for the Citizens Assembly on the topic of "Making Ireland a leader in tackling climate change"

Intergovernmental Panel on Climate Change

I attended the AR6 scoping meeting in Addis Ababa to help scope the WG1 report.

I was a lead author on Chapter 2 of the Working Group 1 contribution to the Fifth Assessment Report. I was also a contributing author to the SPM and ES and Chapters 9 and 10. I attended the final plenary in Stockholm. I also contributed to a cross-chapter box in the Working Group 2 assessment.

For the Fourth Assessment report I was a contributing author to two chapters of the Working Group 1 contribution.

Other assessments

I was a lead author on Chapter 2 and Appendices 3 and 4 of the 2014 US National Climate Assessment. I was also a Lead Author on two chapters of the US CCSP1.1 report on atmospheric temperature trends.

From the 2008 to 2013 edition I have edited or co-edited the global chapter of the annual BAMS State of the Climate series.