Renaturing cities through circular economy because nature does not create waste, we do.


Currently working on:

A Brief History

I am an earth scientist and urban expert based in Amsterdam. As a sustainability consultant at Metabolic, my work includes mapping urban metabolisms and developing evidence-based interventions for circular cities and high-impact sectors. I've given dozens of talks on circular economics for academia and industry across Europe and Taiwan, and co-founded the world’s first summer school on circular cities.

I am also a PhD candidate in ecological engineering, an emerging field which predicts, designs, restores, and manages ecosystems that integrate human society with the natural environment for mutual benefit. In 2018, I was selected for the New Amsterdam Council, the DJ100 (jury-selected list of the Dutch top 100 most sustainable young changemakers), and one of the top digital talents under 26 by The Next Web. I was born in the Netherlands and raised in Canada.

Educational Background


MSc. Earth Sciencescum laude
University of Amsterdam (Institute for Biodiversity and Ecosystem Dynamics)
Program combines geo-ecological sciences with interdisciplinary research.

+ Master thesis on macronutrient cycling of transitioning agroforestry ecosystems in southern Ethiopia at Wageningen University and Research Centre and Hawassa University
+ Internship on aquaponic systems at the circular urban development "De Ceuvel"
+ Fieldwork on biodiversity recovery on agricultural terraces in southern Tenerife
+ Summer school “Planning the Cycling City
+ Education board for MSc. Earth Sciences
+ Secretary for GAOS Association

BSc. Life Scienceshonours
University of Toronto (Department of Earth Sciences)
Program covers the entire biological spectrum, from cell to global ecosystems.

+ Joint minor environmental biology at the National University of Singapore
+ Zoological assistant at Lee Kong Chain Natural History Research Centre
+ Fieldwork on physical and chemical parameters of lake ecosystems
+ Summer school “Transboundary Water Conflict Resolution” at the Hebrew University of Jerusalem
Environmental science and urbanism writer at The Strand: U of T Student Newspaper


For more on my Master's thesis (macronutrient cycling of agroforestry systems), please check out my photoblog which documents my fieldwork in southern Ethiopia. Want to read all 111 pages? You can download the full text here.



Roemers, G., Galle, N.J., & Giezen, M. (2016). Planning the Circular City:
lessons from post-industrial Amsterdam.
Manuscript submitted for Publication to Tollin, N., Morato, J., & Santibanez Gonzalez, E.D. (eds.) Resilient Cities: Rethinking Urban Transformation. UK: Springer Publishing.

Galle, N.J. (2016). What Comes Out, Must Go in: Macronutrient balance assessment of transitioning home gardens in southern Ethiopia (master’s thesis). University of Amsterdam, Amsterdam, The Netherlands.

Awards and Accolades

+ DJ100: jury-selected list of top 100 young, sustainability changemakers (2018)
T500: the definitive list of digital top talents from Holland under 26 (2018)
+ Winner GBDX for Sustainability Challenge: with Global Green City Watch
+ Selected for the New Amsterdam Council: an independent advisory board of 45 talented Amsterdam millennials chosen to provide advice to the real city council

Relevant Skillsets

+ ArcGIS + Material Flow Analysis + Life Cycle Assessment
+ Data collection + Interviewing + Communication + Public speaking
+ Microsoft Excel + Adobe InDesign + Web design
+ Native English speaker + Native Dutch speaker