Analyzing Environmental Changes in Interior Alaska (1982-2014)

Research Sponsored By: US Forest Service
Principal Investigator: L. Monika Moskal
Project Description
This project will use a unique combination of field data, airborne remote sensing, and satellite time series to characterize the spatial heterogeneity of vegetation changes in interior Alaska since 1982. The research emphasizes both temporal and spatial scaling; long time series of observations are needed to track slow changes in vegetation structure and composition in high-latitude systems, and detailed observations from field measurements and high-resolution airborne data (=1 m) are critical to characterize the pattern and process of ecosystem responses in heterogeneous landscapes typical of the ABoVE study domain. This project will use data from NASA Goddard’s Lidar, Hyperspectral, and Thermal (G-LiHT) airborne imager to scale information from large (8 ha) field inventory plots measured in 1982 and re-measured during 2010 to 2017 and low-altitude air photos (1982-83 and 2012-14) on a 20 km grid for the Tanana Valley of interior Alaska (120,000 km2) to satellite spatial (30 m) and spectral resolutions (e.g., Landsat). The multi-scale, multi-sensor approach will specifically target four types of changes using this unique combination of field and airborne remote sensing observations: 1) changes in surface water extent, including drying of wetlands and subsequent encroachment of woody vegetation, 2) post-disturbance vegetation recovery and burn severity, with an emphasis on post-fire succession, 3) biotic disturbances, including mortality and defoliation due to increased insect activity, and 4) forest cover change, emphasizing changes in tree growth (height, diameter) and expansion of woody vegetation at tree line. The complementary nature of these ground and airborne remote sensing observations offers the possibility to develop new, multi-sensor fusion approaches to quantify changes in composition, cover, and productivity for this critical region.