Book excerpt: Recent studies indicate that - due to climate change - the Earth is undergoing rapid changes in all cryospheric components, including polar sea ice shrinkage, mountain glacier recession, thawing permafrost, and diminishing snow cover. This book provides a comprehensive summary of all components of the Earth's cryosphere, reviewing their history, physical and chemical characteristics, geographical distributions, and projected future states. This new edition has been completely updated throughout, and provides state-of-the-art data from GlobSnow-2 CRYOSAT, ICESAT, and GRACE. It includes a comprehensive summary of cryospheric changes in land ice, permafrost, freshwater ice, sea ice, and ice sheets. It discusses the models developed to understand cryosphere processes and predict future changes, including those based on remote sensing, field campaigns, and long-term ground observations. Boasting an extensive bibliography, over 120 figures, and end-of-chapter review questions, it is an ideal resource for students and researchers of the cryosphere.