Thomas Crowther

In January 2020 the Crowther Lab was appointed as scientific advisor to the UN Decade on Ecosystem Restoration, a global initiative highlighting the need for greatly increased global cooperation to restore degraded and destroyed ecosystems, contributing to efforts to combat climate change and safeguard biodiversity, food security, and water supply. On 22 January the World Economic Forum, in partnership with Marc and Lynne Benioff, announced the launch of 1T.org. With the support of Jane Goodall, Inger Andersen, Thomas Crowther and others, it was announced that the platform aimed to facilitate the conservation and restoration of one trillion trees within the decade.

In May 2019 Crowther co-authored research on global mycorrhizal fungal networks, revealing that 60% of trees are connected by ectomycorrhizal fungi (EM) but, as temperatures rise, these fungi - and their associated tree species - will decline and be replaced by arbuscular mycorrhizal fungi (AM). Whilst EM fungi support huge carbon stores, the transition to AM fungi could increase the release of carbon into the atmosphere. The research estimated that if there isn't a reduction in carbon emissions by 2100, there could be a 10% reduction in EM - and the trees that depend on them.

In July 2019 the Crowther Lab published a major paper on 'The Global Tree Restoration Potential'. They identified a global area of 0.9 billion hectares (outside of agricultural and urban areas) available for tree restoration. Studying nearly 80,000 high resolution satellite photographs they analysed tree cover in protected areas largely unaffected by human activity across Earth's ecosystems, from arctic tundra to equatorial rainforest. They used machine learning to identify correlations with key soil and climactic variables in Google Earth Engine to predict the natural level of tree cover which could potentially exist in each ecosystem.

In October 2018 he delivered a keynote address at the 2018 conference for the Association for Forest Spatial Analysis Technologies (ForestSAT), hosted by the NASA Goddard Space Flight Center and the University of Maryland. In February 2019, at the American Association for the Advancement of Science, Crowther announced that scientists had established there was room for an additional 1.2 trillion trees, noting that such a scale of reforestation could be one of the most powerful tools in the fight against climate change.

With the knowledge that there were now three trillion trees on Earth, Plant-for-the-Planet increased their restoration targets and transformed the Billion Tree Campaign into the Trillion Tree Campaign. Crowther is now the lead science advisor to Plant-for-the-Planet. As part of his tree study Crowther was able to compile one of the largest inventories of tree data ever recorded. In 2016 he co-founded the Global Forest Biodiversity Initiative (GFBI) – a foundation which manages the world's largest tree-level forest inventory database with 1.2 million plots from more than 70 countries.

In July 2016, Crowther provided an expert declaration on the carbon cycle, and the sequestration potential of forests and soil for the Western Environmental Law Center to support the proposed Clean Air Rule to limit greenhouse gases in Washington. He went on to give a keynote address at the FAO's 2017 Global symposium on soil organic carbon alongside Nobel Prize winner Dr. Rattan Lal.

After his PhD, Crowther received a postdoctoral fellowship from the Yale Climate and Energy Institute, to pursue his postgraduate research at Yale University. In 2015, Crowther was awarded a Marie Curie fellowship to research the impact of carbon cycle feedbacks on climate change at the Netherlands Institute of Ecology (NIOO). In 2017, Crowther started a tenure track professorship at ETH Zürich. His ongoing research is supported through a unique partnership with DOB Ecology – a private foundation focussed on supporting projects which protect and restore threatened ecosystems across the globe.

Crowther was inspired to conduct his tree study by Plant-for-the-Planet, the youth-led NGO leading the UN's Billion Tree Campaign. After he made the discovery, Crowther's story featured in a textbook to be distributed at global Plant-for-the-Planet Academies, stating "Tom was teased over the years by his fellow Professors for being the 'tree counter'. But Tom stuck with it and on 2 September 2015, his findings were published in the Journal Nature, the most prestigious paper in his field".

Thomas Ward Crowther (born 18 June 1986) is a British scientist specialising in ecosystem ecology and the chief scientific advisor to the UN's Trillion Tree Campaign. He is a tenure-track professor of Global Ecosystem Ecology at ETH Zürich where he formed the Crowther Lab. His work aims to generate a holistic understanding of the global scale ecological systems which regulate the Earth's climate.