He is a former professor of ecology at ETH Zürich and a founding co-chair of the Advisory Board for the United Nations Decade on Ecosystem Restoration.

[1] At ETH Zürich, he started Crowther Lab, an interdisciplinary group of scientists exploring the role of biodiversity in regulating the Earth's climate.

[8] 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).

[21][22][23] Crowther stresses that protecting the soil community might be one of the best way to buffer ecosystems against these potential impacts of climate change.

[25][26] The research also estimated that humans have reduced that number by almost half, and Earth continues to lose around 10 billion trees each year.

[34] If this land could be protected, the study suggested that this is room for one trillion new trees, and the recovering ecosystems could capture over 205 Gt Carbon.

[35] Crowther has described nature restoration as one of the most effective carbon drawdown strategies to date, with the potential to help people, biodiversity, and climate.

[39] In particular, several articles suggested that it is dangerous and misleading to propose that tree planting can be a silver bullet to stop climate change.

[43] Instead, it is about the many solutions that promote the protection, regeneration and sustainable management of nature for local people and the biodiversity that they depend on.

[44][45][46][47] Crowther warned about the risks of mass tree plantations, highlighting the need for socially and ecologically responsible restoration of ecosystems across the globe.