This monograph provides a regional view of global scale climate variability. Most of the chapters focus on the nature and causes of variability in the eastern North Pacific Ocean and western North and South America. Analyses of paleoclimatic, oceanographic, atmospheric, hydrospheric and terrestrial observations are presented. The volume has 23 chapters in 445 pages. This multidisciplinary effort grew out of the Pacific Climate Workshop (PACLIM), an annual gathering of diverse specialists to discuss topics associated with climate variability within that region.