Christina Ravelo’s groundbreaking research on tropical climate variability and change, climate sensitivity, and ocean circulation and thermal structure spans several geological epochs extending from the Miocene and the Pliocene to the Last Glacial Maximum and the Holocene to the present. Her work covers many geographical regions as well — from the subarctic North Pacific to the tropical Indo-Pacific and, more recently, the Southern Ocean. Her contributions to our understanding of global climate change have been profound, innovative and influential, drawing critical links between the climate of the past and that of the future. Christina’s scientific discoveries inspired a generation of students, postdocs and other researchers to study the role of the tropics in the climate system. Christina’s work of the past two decades reinvigorated research on the Pliocene climate. With carbon dioxide concentration at today’s elevated levels, the Pliocene has been long considered a potential analogue to the future greenhouse warming climate. Christina’s and her collaborators’ discovery of a reduced east-west sea surface temperature (SST) gradient along the equator in the Pacific Ocean during the Pliocene epoch was a real game changer, as this gradient controls the atmospheric Walker circulation and has far-reaching effects on global climate. The state with the reduced east-west SST gradient was dubbed a permanent El Niño-like state or, as Christina named it, El Padre. This was a paradigm shift drawing attention to the tropical ocean as a potential driver of climate change on geological timescales. Christina’s latest work combining multiple temperature proxies from different tropical locations confirms her original ideas. Christina has also investigated changes in El Niño-Southern Oscillation (ENSO) through time. In a series of papers, using individual planktonic foraminifera, she has demonstrated that ENSO was weaker during the Pliocene, the Last Glacial Maximum and the early and mid-Holocene than at present, which raises the question of potential impacts of anthropogenic global warming on ENSO. Christina’s scientific discoveries parallel her participation and innovative leadership in the International Ocean Discovery Program (IODP) and its predecessors (Ocean Drilling Program and International Ocean Drilling Program). The current IODP Science Plan (2013-2023) was shaped by her guidance and contributions. Her leadership ushered in a new era of IODP discoveries with mission-specific platform exploration that started in 2003 and continues today. The Ewing Medal is fitting recognition of her outstanding contribution to the field and her truly exceptional and inspiring leadership and influence on the science of paleoclimatology and climate change. — Alexey Fedorov Yale University New Haven, Connecticut Sorbonne University Paris, France

It is a wonderful honor to be this year’s recipient of the Ewing Medal. In receiving this award, I have been given the gift of an opportunity to reflect on my career and express my gratitude to those who have inspired and supported me. I do not take this support for granted. I am a woman of color, the daughter of immigrants, and have not always felt welcome in the scientific spaces that I occupy, code-switching to make it past gatekeepers to enter the worlds of science and academia that are ruled by unfamiliar cultural norms. I say this without bitterness or regret, but out of an obligation to speak my truth. Heartfelt thanks to my inspirational colleagues who see me for who I am and have engaged me in scientific debate and discussion for years: Alexey Fedorov, who nominated me; Matt Huber, Maureen Raymo and Tim Herbert, who supported my nomination; Ivano Aeillo, Mitch Lyle, Yair Rosenthal and Delia Oppo, who are four of my most generous and insightful science comrades; and my University of California, Santa Cruz, family, who nurture and elevate me, including Jim Zachos, my departmental colleagues and my fellow equity warriors. The most gratifying and important research I do is with my students, and I share this award with my 20+ graduate and 200+ undergraduate former and current students. Special thanks to Heather Ford, one of my amazing former students who worked behind the scenes to support this nomination. My career was decidedly transformed by the Ocean Drilling Program (ODP), now the International Ocean Discovery Program (IODP). ODP/IODP is a truly community-driven program, responsible for much of what we know about past climate change, particularly of past warm periods. Serving on panels, working on proposals, participating in expeditions — these opportunities gave me leadership skills and a community of collaborators who have sparked some of my best ideas that have sustained me throughout my career. I would not have earned this award without the unshakeable support of my family and friends. Thanks to my parents; my husband, Roberto; and our three kids, Ezequiel, Michaela and Gina. You continuously entertain and uplift me. A final remark about my truth is about hope. My hope is that we dismantle biased structures and transform our culture to one that welcomes and amplifies the voices of those that have been marginalized. I thank AGU for their leadership in this transformation. — Ana Christina Ravelo University of California, Santa Cruz Santa Cruz, California

For changing our image of the tropical Pacific Ocean during the period when continental ice sheets became recurring features.