This data set consists of seven data files containing measurements from Arctic field sites during the summer months from 5 July 2003 to 5 August 2005 as part of the Land-Atmosphere-Ice Interactions (LAII) International Tundra Experiment (ITEX). Investigators designed this research, which compares an extensive range of vegetation types that exists in widely-separated sites, to help identify the relative vulnerability of different vegetation types, plant functional types, and species to climate change and other forms of disturbances. They evaluated specific parameters to improve understanding of the broad patterns of vegetation change and vegetation function across the Arctic and quantify the constraints on the patterns of growth of arctic-plant feedbacks to the Arctic System. The research sites are located in Alaska, USA; Abisko, Sweden; and Svalbard, Norway. Data are in Microsoft Excel (.xls) format, viewable with spreadsheet software. Data are distributed as an approximately 575 KB compressed ZIP file.