Dear Colleagues, We are writing to encourage you to attend the third Gordon Research Conference (GRC) on Geochronology (https://www.grc.org/geochronology-conference/2025/). This GRC conference will be held August 17-22, 2025 at Sunday River, Maine. The deadline to apply to attend is July 20, 2025. The theme of the 2025 GRC is the "Timing, Tempo and Drivers of Earth’s Climate.” We have an exciting lineup of confirmed discussion leaders and speakers, which is provided below. These include geochronologists as well as scientists whose work is heavily influenced by geochronology. The GRC provides an immersive experience for five days with colleagues in a collegial environment. We hope you will join us in August! There is a limit of 200 participants, so apply to be a poster presenter soon at the website listed above. The 2025 GRC will be preceded by a Gordon Research Seminar (GRS) (https://www.grc.org/geochronology-grs-conference/2025/) planned by and for students and early career researchers. The Geochronology GRS will run August 16-17 at Sunday River, and will include a mentoring session highlighting different career paths and how to overcome common challenges faced by early-career researchers. We hope that group leaders will encourage and support your research groups to attend both the GRS and GRC. Sincerely, GRC Geochronology 2025 Chairs Annie Bauer, Klaudia Kuiper, Marissa Tremblay, Chris Spencer GRS Geochronology 2025 Chairs Francisco Apen, Peter Davidson GRC on Geochronology, sessions and presenters: Climate Extremes in Earth History Discussion Leader: Isabel Fendley, Penn State Dana Royer, Wesleyan University Lyle Nelson, Massachusetts Institute of Technology Jenn Kasbohm, Carnegie Science Earth & Planets Laboratory The Role of Climate in Mass Extinctions Discussion Leader: Blair Schoene, Princeton University Feifei Zhang, Nanjing University Sara Callegaro, University of Bologna Climate and the Solid Earth System Discussion Leader: Emily Cooperdock, Brown University Jeremy Caves-Rugenstein, Colorado State University Thomas Gernon, University of Southampton Andrea Burke, University of St Andrews Orbital Forcing and Pacing of Climate Discussion Leader: Matthias Sinnesael, Trinity College Dublin Mingsong Li, Peking University Margriet Lantink, University of Wisconsin-Madison Thomas Westerhold, University of Bremen MARUM Planetary Habitability Discussion Leader: Vickie Bennett, Australian National University Eva Stueken, University of St Andrews Andrey Bekker, University of California Riverside Sandra Siljeström, RISE Research Institutes of Sweden Human-induced Climate Change: the Anthropocene Discussion Leader: Valerie Trouet, University of Arizona Sloan Coats, University of Hawaii at Manoa Kristine Delong, Louisiana State University Millennial-scale Climate Variability Discussion Leader: Kathleen Johnson, University of California Irvine Jerry McManus, Columbia University Manuel Chevalier, University of Bonn Hominin Evolution and Climate Discussion Leader: Elizabeth Niespolo, Princeton University Kevin Uno, Harvard University Asfawossen Asrat, Botswana International University of Science and Technology Glacier and Landscape Records of Past Climate Discussion Leader: Ryan Venturelli, Colorado School of Mines Taylor Schildgen, GFZ-Potsdam Sarah Shackleton, Woods Hole Oceanographic Institution Power Hour Host: Bereket Haileab, Carleton College Planned Program: GRS in Geochronology 2025 Keynote Session: John Higgins, Princeton University Tempo of Biological and Landscape Evolution (speakers TBD) The Impact of Deep Earth Processes on Climate (speakers TBD) Professional Development for Early-Career Geoscientists Courtney Sprain, University of Florida Emily Cahoon, Isotopx Ltd. Perach Nuriel, University of Geneva Hayden Miller, Los Alamos National Laboratory — Marissa M. Tremblay (she/her) Assistant Professor Purdue University tremblam@purdue.edu 765-494-1255 https://www.eaps.purdue.edu/thermochronology/