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.


I am the project lead on the European Commission Horizon 2020 program project GAIA-CLIM that started in March 2015 and shall run for three years. The project aims to improve our capability to use ground-based and sub-orbital measurements to characterise satellite measurements. It is 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. 


In Spring 2014 the BIPM instigated a task group on the environment under the Consultative Committee on Thermometry. I am a co-opted member on this team. 

Commission for Climatology

Intergovernmental Panel on Climate Change

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.

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