Sarah Bridle, a renowned cosmologist, has made a remarkable transition from studying the cosmos to exploring the intricate world of food. Her journey, as detailed in an interview with Gleb Yakubov, offers a fascinating insight into the crossover between two seemingly disparate fields. Bridle's expertise in physics and data analysis has been instrumental in her new role as a chair in food, climate, and society at the University of York, where she is applying her analytical skills to address some of the most pressing challenges of our time.
A Cosmic Shift to the Dinner Plate
What inspired Bridle's shift from cosmology to food physics? It all started with the passing of David MacKay, a scientist who had made significant contributions to sustainability and energy policy. MacKay's work sparked a deep reflection in Bridle about the impact of human actions on the environment. She began to explore the role of food in climate change, particularly how land use and dietary choices influence greenhouse gas emissions. This newfound interest led her to recognize the 'dark matter' of climate solutions, referring to the underappreciated potential of food systems to mitigate climate change.
The Surprising Complexity of Food Systems
One of the most surprising aspects of Bridle's work is the dominance of social and cultural factors in food systems. She notes that introducing efficient technologies often leads to increased consumption, negating the intended benefits. This phenomenon, known as the 'Jevons paradox', highlights the need for social and cultural change alongside technological advancements. Bridle's approach involves understanding the decision-making criteria of individuals and the complex interplay of incentives, norms, and feedback loops within food systems.
The Limits of Astrophysics Tools in Food Contexts
Bridle's experience with multispectral satellite-imaging techniques for detecting blackgrass in wheat fields illustrates the challenges of applying astrophysics tools to food contexts. She found that variables like soil moisture and rockiness confounded the signals, making it difficult to detect weeds accurately. This experience led her to shift her focus from imaging to broader system modeling, emphasizing the importance of contextual integration and a more holistic understanding of food systems.
The Future Food Calculator: A Quantitative Approach
To address the complexity of food systems, Bridle and her team developed a 'future food calculator'. This quantitative model allows users to explore various interventions, such as on-farm practices, consumer dietary shifts, and land-use choices, and assess their impact on greenhouse gas emissions, self-sufficiency, and land use. The calculator serves as a web-based dashboard, providing a transparent and interactive way to understand the trade-offs and unintended consequences of different food-related decisions.
Balancing Information and Behavior Change
Bridle's work also sheds light on the relationship between information and behavior change. She notes that providing people with information about the health and environmental impacts of food choices often doesn't lead to significant behavioral changes. However, this information increases receptiveness to policy interventions. For instance, public understanding of the link between sugary drinks and type 2 diabetes was crucial in supporting the implementation of a sugary drinks tax.
Creating 'Wow' in the Food Industry
Bridle emphasizes the importance of creating 'wow' in the food industry, particularly in terms of connecting people to the production process. She suggests that community garden projects, for example, can foster respect for food, reduce waste, and increase interest in the natural world. These experiences help people understand the challenges of growing food and the impact of weather on yields, building practical resilience and a deeper connection to the food we eat.
Environmental Labeling: The Power of Transparency
In the realm of environmental labeling, Bridle advises on the importance of transparency. She notes that labels don't always shift individual purchasing behavior as much as expected, but they can significantly influence production. Pilot programs have shown that adding climate labels can lead to changes in what is offered, and tighter thresholds for labels can prompt manufacturers to reformulate products. This highlights the power of transparency in driving positive change.
The Digital Twin of UK Food: A Policymaker's Tool
Bridle is also involved in building a 'digital twin' of the UK food system, which serves as a powerful tool for policymakers. This digital representation allows for the testing of interventions and the assessment of their impact on greenhouse gas emissions and self-sufficiency. For instance, it can help evaluate the effects of soil carbon management practices, such as reducing tillage, and dietary shifts, like reducing red meat consumption. The digital twin enables a transparent comparison of different pathways and the identification of trade-offs and unintended consequences.
Managing Complexity: The Case of Herbicides
The use of herbicides like glyphosate illustrates the complexity of managing trade-offs in food systems. Bridle notes that no-till farming can reduce emissions but may increase reliance on herbicides if weed pressure rises. The key is to quantify these interactions at the system level and compare pathways transparently, rather than assuming a single intervention is universally better in isolation. This approach ensures a more nuanced understanding of the potential impacts of different practices.
Data Practices and Collaboration: Learning from Astrophysics
Bridle reflects on the similarities and differences between data practices in food physics and astrophysics. She notes that food physics is at a stage similar to astrophysics 20-30 years ago, with a focus on quantitative modeling and open-source practices. However, she highlights the need for standards, shared datasets, open code, and coordinated efforts to advance the field. Bridle encourages physicists and mathematicians to follow in her footsteps by contributing to transparent models, shared datasets, and collaborative efforts, drawing inspiration from the success of modern astrophysics consortia.
A Call to Action for Food Scientists
Bridle offers practical advice for those interested in following her path. She emphasizes the importance of quantitative modeling, open-source practices, and Python-based tooling. She encourages building transparent models, shared datasets, and collaborative efforts, and adopting open-science habits in food-system work. One concrete step is to publish code and assumptions, contribute quantitative skills to cross-disciplinary teams, and translate findings into accessible tools for policymakers and the public.
Motivation and Vision for the Future
Bridle's motivation stems from a desire to address the urgent challenges of climate change and food security. She envisions a future where the UK food system is aligned with net-zero targets, land is used more efficiently, and low-impact diets are easy by default. She hopes that open, quantitative modeling with transparent code and assumptions becomes embedded in policymaking, leading to a more sustainable and resilient food system. Bridle's journey from cosmology to food physics is a testament to the power of interdisciplinary collaboration and the potential for positive change through innovative thinking and practical action.
