The last 65 Ma of Earth's history, the Cenozoic, has been a time characterized by significant climate change. Major global changes included massive tectonic reorganization, a reduction in atmospheric pCO2 (Pagani et al., 1999; Pearson and Palmer, 2000), and a dramatic cooling of global climate, plunging the world from generally warm conditions into the repeated glacial-interglacial cycles of the ice age (Zachos et al., 2001). Deep-sea oxygen isotope records record global cooling of up to 8°C in the early Cenozoic, heralding the development of major ice sheets on Antarctica from 35 Ma, which further intensified the global cooling trend and cul-minated in cyclical Northern Hemisphere glaciation during the past 3 Ma (figure 4.1). Many events in global tectonics and high latitude climate had significant effects on Ceno-zoic climate evolution. These are well described elsewhere (e.g., Kennett, 1995; Denton, 1999; Zachos et al., 2001) and are summarized in figure 4.1. In this chapter, we focus on three revolutions in climate research that have dramatically altered our perception of global and African climate. First, the discovery that large magnitude climate events occurred abruptly, sometimes in as little as decades, has prompted high-resolution paleocli-mate reconstructions and new conceptions of climate dynamics, revealing significant climate variability at times that were previously thought to be quiescent (e.g., the Holocene). On longer timescales, high-resolution oxygen iso-tope stratigraphies have also revealed transient events in the early Cenozoic (Zachos et al., 2001). These discoveries have revolutionized theories of climate change and demonstrated the need for high-resolution reconstruction of climate vari-ability on 10 0 -to 10 5 -year timescales. Second, recent climate studies have revealed significant tropical climate variability. Modern observational climate data have indicated that the largest mode of global interan-nual climate variability is the El Niño Southern Oscillation (ENSO) in the tropical Pacific (Ropelewski and Halpert, 1987; Trenberth et al., 1998). Large amplitude tropical environ-mental variability has also been reconstructed in the paleo-climate record. In particular, revised estimates of tropical sea surface temperatures (SSTs) during global cool and warm events have revealed significant tropical sensitivity to global climate change (e.g., Pearson et al., 2001; Lea et al., 2003). Revised tropical SST reconstructions have implications both for local climate interpretations and for global dynamical predictions, leading to new perspectives on the nature of Cenozoic climate change. Third, the role of the tropics in global climate change has been reconceptualized. Rather than being a passive responder to changes in the high-latitude cryosphere, tropical climate variability may be at least partially decoupled from high-latitude climate. For example, there is considerable evidence that precessional variations in insolation may directly influ-ence the intensity of African precipitation, independent of high-latitude climate variability (Rossignol-Strick, 1983; Partridge et al., 1997; Denison et al., 2005). The tropics may even have driven global climate change. For example, ENSO generates global teleconnections that have been observed in the instrumental record (Cane and Zebiak, 1985; Cane and Clement, 1999), and evidence for tropical initiation of past global climate changes comes from both paleoclimate and modeling analyses (Linsley et al., 2000; Clement et al., 2001; Hoerling et al., 2001; Yin and Battisti, 2001). This chapter provides a synthesis of climate data from a tropical perspec-tive that offers new insights into aspects of Cenozoic African environmental change.