Probabilistic estimates of landscape change in Alaska (1984 to 2015)

Contemporary climate change in Alaska has resulted in amplified rates of press and pulse disturbances that drive ecosystem change with significant consequences for socio-environmental systems. Despite the vulnerability of Arctic and boreal landscapes to change, little has been done to characterize landscape change and associated drivers across northern high-latitude ecosystems. Here we characterize the historical sensitivity of Alaska’s ecosystems to environmental change and anthropogenic disturbances using expert knowledge, remote sensing data, and spatiotemporal analyses and modeling. Time-series analysis of moderate– and high-resolution imagery was used to characterize land and water-surface dynamics across Alaska. Some 400,000 interpretations of ecological and geomorphological change were made using historical air photos and satellite imagery, and corroborate land surface greening, browning, and wetness/moisture trend parameters derived from peak-growing season Landsat imagery acquired from 1984 to 2015. The time series of change metrics, together with climatic data and maps of landscape characteristics, were incorporated into a modeling framework for mapping and understanding of drivers of change throughout Alaska. According to our analysis, approximately 13% (~174,000±8700 km2) of Alaska has experienced change in the last 32 years (±95% confidence intervals).