Hannah Stefenoni champions the sustainability efforts for Clover Sonoma’s network of 30 small family-owned dairy partners. As a key liaison with the company’s family of farmers, Stefenoni focuses on minimizing Clover Sonoma's environmental footprint by continuously improving the health of the soil, the quality of the milk, the health and welfare of the animals, and greenhouse gas reduction initiatives while maximizing a positive impact for farmers by cultivating on-farm longevity, resiliency, and profitability enhancements.

With over ten years of experience in environmental stewardship and studying the relationship between livestock agriculture and greenhouse gas reduction, Hannah is an expert in methane emissions reduction, on-farm sustainability, and regenerative agriculture practices on a dairy farm. In 2022, under Hannah’s leadership, Clover Sonoma began testing Blue Ocean Barns’ Brominata™, a dehydrated form of a red seaweed that is proven to cut cows' methane emissions from burps without changing the taste of milk. During the trial phase, the Clover Sonoma dairy cows fed Brominata achieved over a fifty percent reduction in methane while still producing delicious dairy.

Raised on a dairy farm in Northern California, she pursued her undergraduate studies at Oklahoma State University, where she received her degree in Animal Science and began her research into methane emissions from cows. Hannah earned a Master of Science degree in Animal Sciences from Washington State University, where she was involved in feed additive research with cows and sustainability research around how feeding cows byproducts can improve human-edible protein conversion efficiency. Later, as a Ph.D. candidate at Pennsylvania State University, Hannah was one of the first to feed Asparagopsis taxiformis (aka red seaweed) to cows while assessing the impact of greenhouse gas emissions from animal agriculture. Several of the research projects that Hannah co-authored have been published by the American Dairy Science Association and Journal of Dairy Science.

Hannah sits on the Marin Carbon Project steering committee, working to enhance carbon sequestration and greenhouse gas emissions reduction in agricultural ecosystems through applied research, demonstration, and implementation. Additionally, Hannah works with the Clover Sonoma community of family of dairies to ensure they are compliant with the Dairy Standards Agency, the USDA's National Organic Program, American Humane Certified welfare standards, and milk quality standards. Hannah is a member of Food Tank's CSO Group, which brings together sustainability leaders from over 80 major businesses to converse, mentor, and present case studies to inspire meaningful change in the private sector.