Collaborative Research: Exploring the Dynamics of the Active Layer and Near-Surface Permafrost across the North Slope of Alaska

Stanford University, Stanford CA

Investigators

Abstract

The overall objective of the proposed research is to investigate changes in the dynamics of the active layer and the top layers of ice-rich permafrost on the North Slope of Alaska using InSAR (Interferometric Synthetic Aperture Radar). We will use both C-band and L-band data, acquired during the last two decades (1991-2011). More specifically, (i) we will implement the InSAR Frozen Ground Algorithm (InSAR FGA) to detect changes in ALT and near-surface permafrost, (ii) we will investigate spatial variations of ALT and ground ice content of the near-surface permafrost through drilling, mechanical probing, and ground penetration radar (GPR). Data and information obtained from this fieldwork will also be used for InSAR FGA validation and calibration, (iii) combining InSAR FGA outputs, field data, and available climate data, we will investigate spatial and temporal changes and variations of the active layer and near-surface permafrost and their response to climate change from 1991 through 2011 on the North Slope of Alaska. The expected results of the proposed research will provide (i) a validated InSAR FGA useful for regional-scale active layer and permafrost studies; (ii) time series of ALT and their changes over the study period, (iii) long-term (1991-2011) mean of ALT across the North Slope of Alaska, and (iv) potential ground-ice melting in the top layers of ice-rich permafrost across the North Slope of Alaska with a resolution of from tens of meters to hundreds of meters. The results from this study will be ideal for model inputs and validation and can be used to assess risk to human infrastructure in the Arctic. The postdoc Liu will gain educational experience by mentoring an undergraduate student in the Summer Research in Geoscience and Engineering program, and results will be disseminated to the public through the NSIDC All about Frozen Ground website and via lectures at the Fiske Planetarium and Boulder Public Library.