Sarah E. Perkins-Kirkpatrick ^1* Lisa Alexander ² Andrew King ³ Sarah Kew ⁴ Sjoukje Philip ⁴ Clair Barnes ⁵ Douglas Maraun ⁶ Rupert Stuart-Smith ⁷ Aglae Jezequel ^8,9 Emanuele Bevacqua ¹⁰ Samantha Burgess ¹¹ Erich M. Fischer ¹² Gabriele Hegerl ¹³ Joyce Kimutai ⁵ Gerbrand Koren ¹⁴ Kamoru A. Lawal ^15,16 Seung-Ki Min ¹⁷ Mark New ¹⁸ Romaric C. Odoulami ¹⁶ Christina M. Patricola ¹⁹ Izidine Pinto ⁴ Aurelien Ribes ²⁰ Tiffany Shaw ²¹ Wim Thiery ²² Blair Trewin ²³ Robert Vautard ²⁴ Michael Wehner ²⁵ Jakob Zscheischler ²⁶

• ¹ Australian National University, Canberra, Australia
• ² University of New South Wales, Kensington, New South Wales, Australia
• ³ The University of Melbourne, Parkville, Victoria, Australia
• ⁴ Royal Netherlands Meteorological Institute, De Bilt, Netherlands
• ⁵ Imperial College London, London, England, United Kingdom
• ⁶ University of Graz, Graz, Styria, Austria
• ⁷ Smith School of Enterprise and the Environment, University of Oxford,, Oxford, England, United Kingdom
• ⁸ École des ponts ParisTech (ENPC), Marne-la-Vallée, Île-de-France, France
• ⁹ Laboratoire de Météorologie Dynamique, Sorbonne Université (CNRS), Paris, Île-de-France, France
• ¹⁰ Department of Compound Environmental Risks, Helmholtz Centre for Environmental Research, leipzig, Germany
• ¹¹ European Centre for Medium-Range Weather Forecasts, Reading, United Kingdom
• ¹² ETH Zürich, Zurich, Zürich, Switzerland
• ¹³ University of Edinburgh, Edinburgh, Scotland, United Kingdom
• ¹⁴ Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, Netherlands, Netherlands
• ¹⁵ African Center of Meteorological Application for Development (ACMAD), Niamey, Niger
• ¹⁶ African Climate and Development Institute, University of Cape Town, Cape Town, South Africa
• ¹⁷ Division of Environmental Science and Engineering, Pohang University of Science and Technology, Pohang, Republic of Korea
• ¹⁸ Department of Environmental and Geographical Science, Faculty of Science, University of Cape Town, Cape Town, Western Cape, South Africa
• ¹⁹ Department of Geological and Atmospheric Sciences, College of Liberal Arts and Sciences, Iowa State University, Ames, Iowa, United States
• ²⁰ Centre National de Recherches Météorologiques, Université de Toulouse, Météo-France, Toulouse, France
• ²¹ Department of Geophysical Sciences, Division of Physical Sciences, The University of Chicago, Chicago, Illinois, United States
• ²² Department of Water and Climate, Vrije Universiteit Brussel, Brussels, Belgium
• ²³ Bureau of Meteorology (Australia), Melbourne, Victoria, Australia
• ²⁴ Institut Pierre-Simon Laplace, CNRS, Université Paris-Saclay, Sorbonne Université, Paris, France
• ²⁵ Lawrence Berkeley National Laboratory, Berkeley, United States
• ²⁶ Department of Hydrosciences, TUD Dresden University of Technology, Dresden, Germany

The field of extreme event attribution (EEA) has rapidly developed over the last two decades. Various methods have been developed and implemented, physical modelling capabilities have generally improved, the field of impact attribution has emerged, and assessments serve as a popular communication tool for conveying how climate change is influencing weather and climate events in the lived experience. However, a number of non-trivial challenges still remain that must be addressed by the community to secure further advancement of the field, whilst ensuring scientific rigour and the appropriate use of attribution findings by stakeholders and associated applications. As part of a concept series commissioned by the World Climate Research Programme, this paper discusses contemporary developments and challenges over six key domains relevant to EEA, and provides recommendations of where focus in the EEA field should be concentrated over the coming decade.These six domains are: 1) observations in the context of EEA; 2) extreme event definitions; 3) statistical methods; 4) physical modelling methods; 5) impact attribution; and 6) communication. Broadly, recommendations call for increased EEA assessments and capacity building particularly for more vulnerable regions; contemporary guidelines for assessing the suitability of physical climate models; establishing best-practise methodologies for EEA on compound and record-shattering extremes; coordinated interdisciplinary engagement to develop scaffolding for impact attribution assessments and their suitability for use in broader applications; and increased and ongoing investment in EEA communication. To address these recommendations requires significant developments in multiple fields that either underpin (e.g. observations & monitoring; climate modelling), or are closely related to (e.g. compound & record-shattering events; climate impacts) EEA, as well as working consistently with experts outside of attribution and climate science more generally. However, if approached with investment, dedication, and coordination, tackling these challenges over the next decade will ensure robust EEA analysis, with tangible benefits to the broader global community.