Polynyas are relatively ice-free regions when compared to the areas around them, and have been suggested as being foci for energy transfer between the atmosphere and ocean, ice factories, and critical areas with respect to polar ecosystems and biogeochemical cycles. This volume presents an integrated, multidisciplinary review of polynyas in both the Arctic and Antarctic. It emphasizes the meteorology, ice dynamics, oceanography, biological components, chemistry, and modeling of these systems, particularly with respect to their roles in polar processes and distributions. The various interactions within polynyas, particularly between the physical forcing and biological responses, is emphasized, as are the potential changes in polynyas that might occur under a climate regime that is rapidly changing. The authors of the reviews are leaders among their respective countries in polynya research, and all are internationally recognized. Addresses the findings from actively researched polynyas and reports on the new understandings of polar systems that have evolved from these studies. Includes topics from meteorology to physics to biology and chemistry, and seeks to integrate them into a synthetic assessment. Provides material from both the Arctic and Antarctic, which is highly unusual in books of this type.