Methane is an important radiatively active trace gas. As its atmospheric concentration has more than doubled since pre-industrial times, a need to understand the processes involved driving methane exchange between lithosphere and atmosphere exists, especially in the context of climate change, where the Arctic is of major interest. This book aims at providing spatially highly resolved small-scale methane flux measurements of the Arctic wet polygonal tundra on Samoylov Island in the Lena River Delta region of North Siberia. Small-scale process understanding is needed to understand and interpret ecosystem-scale measurements provided by methods, where the focus is primarily put on high temporal resolution. For this purpose, an extensive array of micro-sites for plot-based methane flux measurements sampled on an almost daily basis through summer season 2006. The data set presented in this book is unique with regard to its extend, the investigation area, and its further potential for integrating flux measurements on different spatial scales. This book is adressed to readers with environmental science background interested in Arctic climate change and greenhouse gas sources.