Dr. Dan Li’s scientific accomplishments and international reputation are now setting new trends in global environmental change (GEC). His work on how urbanization interacts with the climate system has skillfully welded GEC and corollary fields including atmospheric sciences, biogeosciences, Earth sciences, urban sciences, and hydrology. Dan’s work began with local scales and then progressed to global scales, embedding coupled urban and hydrological mechanisms into weather and climate models. His work on the role of urban-rural evapotranspiration differential during heat waves has shaped the discourse and subsequent work of many groups. He has infused contemporary issues from multiple fields such as green infrastructure, deforestation, and Earth greening as a perturbation to the hydrological cycle and tracked their ramifications to GEC across many scales. His research demonstrates unique skills in the development of simplified yet robust models that inform, with ingenuity and foresight, the complex coupling of the energy and water cycles at Earth’s rapidly urbanizing surface and the development of land-based climate mitigation and adaptation strategies to benefit from them. His findings on causes and effects of daytime urban heat islands (UHIs) simultaneously stirred new debates and reconciled earlier controversies. Many of the theoretical tactics Dan employed can be traced back to his study of turbulent flows in hydraulics as an undergraduate student and atmospheric sciences as a doctoral student. His research advanced how turbulence in the atmospheric boundary layer interacts with natural and urban roughness, which was a necessary first step to studies on urban climate interactions. He developed physical and theoretical foundations for empirical laws in atmospheric turbulence that have been widely used but had only been validated on phenomenological grounds. Dan has also spearheaded new parameterizations that accommodate the urban environment in weather, climate, and Earth system models, which are necessary for any quantification of the effectiveness of urban heat mitigation strategies on the climate system. Dan appreciates the significance of communicating the consequences of GEC science to the public and the broader scientific community at large. He has made all the necessary efforts to translate his findings into terms that engage the public, especially given the media attention to UHIs and associated interactive effects of urbanization and climate change. Dan is an exceptional scholar with poly-credentials and stature to make him an outstanding recipient of the Global Environmental Change Early Career Award and a perfect ambassador for the future of global environmental change research. —Gabriel Katul, Duke University, Durham, N.C.

I am profoundly honored to receive the AGU Global Environmental Change Early Career Award. This accolade provides a perfect opportunity for me to express my deepest gratitude to my Ph.D. adviser, Prof. Elie Bou-Zeid, as well as my undergraduate adviser, Prof. Xiping Yu. Their influence on my development as a scientist cannot be overstated. My deepest gratitude also goes to my mentor and long-term collaborator, Prof. Gaby Katul, who stands as an unparalleled role model. Additionally, I extend heartfelt thanks to my distinguished nominators: Prof. Heping Liu and Prof. Pierre Gentine. My childhood fascination with the movement of water and air perhaps predestined my dedication to the field of environmental fluid mechanics. To date, many seminal questions in turbulence and hydraulics that once captivated leading physicists remain open. Revisiting these old questions, which form the foundational intersections between atmospheric sciences, hydrological sciences, biogeosciences, and Earth sciences, remains vital as we tackle the new challenges of global environmental change. At the same time, the complexities associated with global environmental change require us to embrace new data, techniques, concepts, and solutions. As I reflect on my intellectual journey, I’m immensely grateful to the prestigious institutions that have shaped me: Tsinghua University, Princeton University, the Geophysical Fluid Dynamics Laboratory, and Boston University. This gratitude extends to countless individuals from all over the world who have generously guided and supported me along the way. Here I want to particularly thank my colleagues at Boston University, Profs. Guido Salvucci, Lucy Hutyra, Mark Friedl, and Sergio Fagherazzi, to name a few, who are amazing to work with. The daily interaction with the postdocs, Ph.D. students, visiting scholars, undergraduates, and high school researchers in my group continually inspires me. Their curiosity, drive, and innovative thinking fuel my own passion and dedication to our collective work. In closing, none of this journey would have been conceivable without the steadfast support of my partner, Wei. Wei’s unfaltering faith in me has been the guiding light through even the darkest days of my journey, providing the comfort and confidence I needed to not only survive but also to thrive. Thank you, Wei, for being my anchor throughout this adventure. —Dan Li, Boston University, Boston