Hannah Ritchie

Hannah Ritchie (born 1993) is a Scottish data scientist who is a senior researcher at the University of Oxford in the Oxford Martin School, and deputy editor at Our World in Data. Her work focuses on sustainability, in relation to climate change, energy, food and agriculture, biodiversity, air pollution, deforestation, and public health.

She has published two books, Not the End of the World in 2024 and Clearing the Air in 2025.

Early life and education Hannah Ritchie was born in 1993 in Falkirk, Scotland, United Kingdom. She trained in environmental science at the University of Edinburgh. She earned her undergraduate degree in environmental geoscience and a master's degree in carbon management.

She remained in Scotland for her PhD, researching malnutrition and global food systems. She created a scalable framework to understand food system pathways and identify losses, allocations, and conversions. In particular, she looked to understand whether it was possible to feed a growing population without damaging the environment. Ritchie is vegan. She left Edinburgh to start a research position at the University of Oxford, where she developed data visualisations to communicate information. For example, she has argued that for most foods, the carbon footprint is barely impacted by transport.

In 2017, Ritchie joined Our World in Data as Head of Research. Her work focuses on environmental sustainability, including topics such as climate change, energy, food and agriculture, biodiversity, air pollution, and deforestation. During the COVID-19 pandemic, she built the Our World in Data COVID-19 information dashboard. In 2023 she became Deputy Editor and Lead Researcher.

In 2024, Chatto & Windus published Ritchie's first book, Not the End of the World, which explores her optimism for large-scale problem-solving and ending climate change.

In 2025, Ritchie published a second book, titled Clearing the Air.

She also authors a newsletter titled "Sustainability by numbers", with over 60,000 subscribers.

Recognition In 2022 Ritchie was named Scotland's Youth Climate Champion at the Holyrood Green Giant Awards in recognition of her contributions to the climate-change movement. In 2024, Ritchie was recognised for lifetime achievement with honorary fellowship of the Royal Statistical Society.

In 2025, she received the honorary award "Inspiration from Abroad" from the jury of the Climate Change Communication Award, presented by the United Nations Information Center in Prague and the Learned Society of the Czech Republic.

Selected publications

Books

Articles