Piers Forster

Professor Piers Forster CBE FRMetS

Professor Piers Forster is one of the world's leading atmospheric physicists and climate scientists, renowned for quantifying the causes of climate change and translating complex climate science into evidence that shapes international policy and national action. His scientific contributions span radiative forcing, climate sensitivity, aviation–climate interactions, climate modelling, carbon budgets, and the annual tracking of global climate indicators—research that underpins climate assessments used by governments worldwide.^[1][2]

Forster has played central roles in four cycles of the Intergovernmental Panel on Climate Change (IPCC), serving as Co-ordinating Lead Author for the Fourth Assessment Report, Lead Author for the Fifth Assessment Report and Co-ordinating Lead Author for the Sixth Assessment Report (AR6), as well as Lead Author of the 2018 IPCC Special Report on Global Warming of 1.5 °C.

He also leads the international Indicators of Global Climate Change (IGCC) project, which provides annual updates on the state of the climate system and human influence, filling critical gaps between IPCC cycles and informing real-time climate decision-making. IGCC annual updates are among the most cited and discussed climate science papers published each year.

Beyond academia, Forster has shaped UK climate policy as a member of the UK Climate Change Committee since 2019 and served as its Chair from 2023 to 2025, guiding the UK's pathway to net zero during a period of political transition. He was awarded a CBE in the 2026 New Year Honours for his services to tackling climate change.

His research recognitions include the Royal Society Wolfson Research Merit Award (2011), election as Fellow of the American Geophysical Union (2019), the Natural Environment Research Council (NERC) Research Impact Award (2023), the Royal Meteorological Society’s Climate Science and Communications award (2025) and recognition as a Web of Science Highly Cited Researcher every year from 2019 to 2025.

Career Development and Major Highlights

Early Career and Training (1987–2005)

Forster's career began with a BSc in Physics from Imperial College London (1990), followed by a PhD in Meteorology from the University of Reading (1994). His doctoral research launched a sustained focus on understanding how different atmospheric constituents—greenhouse gases, aerosols, and clouds—alter Earth's radiation balance and drive climate change.

After completing his PhD, Forster held postdoctoral research positions at the Universities of Reading and Colorado and won a Royal Society overseas fellowship to Australia (1994–2000), developing expertise in radiative transfer modelling and climate feedbacks. In 2000, he was awarded a prestigious NERC Advanced Research Fellowship at the University of Reading (2000–2005), establishing himself as a rising expert on radiative forcing—the change in Earth's energy balance caused by human and natural factors which ultimately drives all climate change.

Building a Research Programme at Leeds (2005–present)

Forster joined the University of Leeds in 2005 as a Roberts Research Fellow and Reader, and was promoted to Professor of Physical Climate Change in 2008, a position he holds today. At Leeds, he built an internationally recognised research group focused on quantifying climate drivers and responses, with a particular emphasis on translating physics into policy-relevant insights.

In 2016, he founded and became the inaugural Director of the Priestley Centre for Climate Futures, a flagship interdisciplinary research centre bringing together over 300 academics at Leeds to deliver world-class climate science, mitigation strategies, and adaptation solutions. Under his leadership, the Priestley Centre has become a global hub for climate research, reaching into every continent and delivering excellent research to underpin robust and timely climate solutions.

Leadership in IPCC Assessments (2001–2023)

Forster's influence on global climate science is perhaps most visible through his sustained contributions to the IPCC, the authoritative international body for climate assessment. His IPCC roles have evolved over two decades and include:

• Fourth Assessment Report (AR4, 2007): Co-ordinating Lead Author, Chapter 2 (Atmospheric Constituents and Radiative Forcing). This chapter established the scientific basis for understanding how human emissions drive global warming through changes in Earth's energy balance.
• Fifth Assessment Report (AR5, 2013): Lead Author, Chapter 8 (Anthropogenic and Natural Radiative Forcing). And core writing team member for the Synthesis Report Forster helped refine the "effective radiative forcing" concept, improving the quantification of climate drivers and their uncertainties.
• IPCC Special Report on Global Warming of 1.5 °C (SR1.5, 2018): Lead Author. This landmark report, requested by the Paris Agreement, assessed pathways to limit warming to 1.5 °C and catalysed global ambition on climate action.
• Sixth Assessment Report (AR6, 2021): Co-ordinating Lead Author, Chapter 7 (The Earth's Energy Budget, Climate Feedbacks, and Climate Sensitivity). Forster led the most comprehensive assessment to date of Earth's energy imbalance, climate sensitivity, and the remaining carbon budget—science that underpins every subsequent climate target and policy.

These roles included contributions to Chapters across the reports and serving as a drafting author and negotiator for the Summary for Policy Makers — the Government approved summaries. The IPCC, alongside Al Gore, was awarded the 2007 Nobel Peace Prize for its work on climate change, recognising the collective contribution of scientists including Forster.

Pioneering Annual Climate Indicators (2023–present)

Recognising that the multi-year IPCC cycle leaves gaps in real-time climate understanding, Forster leads the Indicators of Global Climate Change project, an international collaboration that provides annual updates on key climate system indicators: greenhouse gas emissions and concentrations, radiative forcing, Earth's energy imbalance, surface temperature changes, human-attributed warming, remaining carbon budgets, and global temperature extremes.

Published in the open-access journal Earth System Science Data, these annual assessments have become essential references for evidence-based climate discussion and planning between IPCC reports. The 2024 update, for example, documented that human-driven radiative forcing reached 2.97 W/m² and that the record temperatures of 2024 were dominated by human activity, with the 1.5 °C carbon budget smaller than ever. This work is widely cited by policymakers, researchers, and climate communicators worldwide and exemplifies Forster's commitment to making climate science timely, transparent, and actionable.

Shaping UK Climate Policy (2019–2025)

In 2019, Forster was appointed to the UK Climate Change Committee (CCC), the UK's independent statutory adviser on climate targets and progress. When Lord Deben stepped down after two terms as Chair in 2023, the UK Government appointed Forster as Interim Chair, a role he held until mid-2025.

During his tenure as Interim Chair, Forster steered the CCC through a politically sensitive period, including the transition from Conservative to Labour government in 2024. He maintained the Committee's reputation for non-partisan, evidence-based advice while guiding the production of major reports, including the 7th Carbon Budget Report and the 2025 Progress Report to Parliament. Under his leadership, the CCC became "more optimistic" that the UK could meet its climate commitments, pointing to accelerating clean-energy adoption and improved policy ambition.

Forster has consistently emphasised that the CCC's role is to provide the best possible evidence, not to set policy—a distinction he defended publicly in the face of political attacks on climate action. He has been a clear voice for the economic benefits of net zero, arguing that decarbonisation will "ultimately, be good for the UK economy."

Research Leadership and Innovation

Forster has led major research programmes addressing frontier questions in climate science:

• EU Horizon 2020 CONSTRAIN Project: Coordinated a pan-European effort to accurately predict global temperature change, producing influential work on climate sensitivity and near-term warming.
• Aviation and Climate: Principal investigator of multiple projects assessing the climate impact of aviation, including contrails, alternative fuels, and future aircraft architectures (FlyZero, MAGICA, TOZCA). His work has shown that aviation's non-CO₂ effects (especially contrails) are significant contributors to warming and must be addressed in decarbonisation strategies.
• Climate Engineering (Geoengineering): Led the Integrated Assessment of Geoengineering Proposals project and has expressed doubt that geoengineering could be deployed effectively, emphasising the need for emissions reductions.

Forster's research is characterised by rigorous quantification, transparency in uncertainty, and a focus on policy relevance. He has published extensively in leading journals and is among the most highly cited climate scientists globally.

Community Engagement and Environmental Action

Beyond his academic and policy roles, Forster has championed local environmental action. He co-founded the United Bank of Carbon, a UK charity that researches and protects trees and forests. He is patron of Zero Carbon Harrogate and a long-time supporter of Long Lands Common, Harrogate's first community-owned woodland project. In 2025, a section of Long Lands Common was named Forster Wood in recognition of his contributions to climate science and community environmental leadership—an honour Forster described as meaning "the most" of any he has received.

He has also served as Academic Lead for the University of Leeds' own Climate Plan, driving institutional decarbonisation and embedding climate action across campus.

Direction of Travel

As Forster looks ahead, his work is oriented toward three interrelated goals: advancing the science of near-term climate prediction, bridging the gap between science and action, and supporting the global transition to real zero.

Advancing climate science for decision-making: Forster continues to lead the annual Indicators of Global Climate Change project, ensuring that policymakers, businesses, and the public have access to the latest, most robust evidence on the state of the climate system. He is expanding this work to include regional climate extremes and improved tracking of mitigation progress, including tracking the phase out of fossil fuel use.

Bridging science and policy: Following his tenure as Interim Chair of the Climate Change Committee, Forster remains a CCC member (reappointed in 2025) and continues to translate complex climate physics into non-partisan advice for government. He has emphasised the need for climate policy to remain grounded in evidence, resist politicisation, and focus on the economic and social opportunities of decarbonisation.

Leading interdisciplinary climate solutions: Through the Priestley Centre, Forster is fostering interdisciplinary collaboration that spans fundamental climate science, mitigation pathways, and adaptation strategies. Recent innovations include reimagining academic conferences as "Sustainable Conference Living Labs," for which Leeds won the Outstanding Innovation in Conferences award in 2025. He is also establishing a Climate Evidence Unit at Leeds to ensure that climate research is accessible, usable, and impactful for decision-makers.

Championing a just and evidence-based transition: Forster has been vocal about the need for climate action to be both ambitious and equitable. His recent public interventions have defended climate science from political attack, clarified the CCC's advisory (not policymaking) role, and underscored that net zero is not only possible but economically beneficial. He has also highlighted the urgency of making electricity cheaper relative to gas to unlock the benefits of electrification for households, businesses, and industry.

With his CBE, election to major scientific societies, and sustained impact on both climate science and policy, Forster exemplifies the modern climate scientist: rigorous, interdisciplinary, engaged with society, and committed to evidence-based solutions at every scale—from global climate assessments to community woodlands. His ongoing work will continue to shape how the world understands, responds to, and ultimately solves the climate crisis.