Explore the Pliocene Warm Period and the onset of Northern Hemisphere glaciation in this 56-minute Emiliani Lecture from the AGU Fall Meeting 2008. Delve into Ana Christina Ravelo's presentation, which covers topics such as global ice volume, ice rafts of debris, predicted equilibrium temperature, and the tropical Pacific. Examine various scientific methods including alkane saturation index and magnesium calcium values. Gain insights from modeling studies, ocean heat budget analysis, and forced models. Discover important lessons and future directions for climate research, and engage with the Q&A session that follows the lecture.