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This release contains Active Layer Thickness (ALT) and Organic Layer Thickness (OLT) measurements measured along transects in Alaska, 2015. Site condition information in terms of wildfire burns is also included.
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Geophysical measurements were collected by the U.S. Geological Survey (USGS) at five sites in Interior Alaska in September 2021 for the purposes of imaging permafrost structure and quantifying variations in subsurface moisture content in relation to thaw features. Borehole nuclear magnetic resonance (NMR) data were collected at two sites in order to determine liquid water content at depth in shallow boreholes. NMR data were collected in a 2.25 m-deep borehole at the North Star golf course adjacent to one of the ERT profiles, and in another two 1.625 m-deep boreholes adjacent to Big Trail Lake where previous NMR measurements were made in 2019 and 2020.
Electrical resistivity tomography (ERT) measurements were collected by the U.S. Geological Survey (USGS) at two sites in Interior Alaska in September 2019 for the purposes of imaging permafrost structure and quantifying variations in subsurface moisture content in relation to thaw features. First, ERT data were collected at Big Trail Lake, a thermokarst lake outside of Fairbanks, Alaska, to quantify permafrost characteristics beneath the lake and across its shorelines. Three 222 m ERT survey lines were collected perpendicular to the North, East, and South shorelines, and two 110 m lines were collected parallel to the southeast and northeast shorelines. Models of electrical resistivity produced from these data revealed...
Carbon release from thawing permafrost soils could significantly exacerbate global warming as the active-layer deepens, exposing more carbon to decay. Plant community and soil properties provide a major control on this by influencing the maximum depth of thaw each summer (active-layer thickness; ALT), but a quantitative understanding of the relative importance of plant and soil characteristics, and their interactions in determine ALTs, is currently lacking. To address this, we undertook an extensive survey of multiple vegetation and edaphic characteristics and ALTs across multiple plots in four field sites within boreal forest in the discontinuous permafrost zone (NWT, Canada). Our sites included mature black spruce,...
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Fire can be a significant driver of permafrost change in boreal landscapes, altering the availability of soil carbon and nutrients that have important implications for future climate and ecological succession. However, not all landscapes are equally susceptible to fire-induced change. As fire frequency is expected to increase in the high latitudes, methods to understand the vulnerability and resilience of different landscapes to permafrost degradation are needed. Geophysical and other field observations reveal details of both near-surface (less than 1 m) and deeper (greater than 1 m) impacts of fire on permafrost along 14 transects that span burned-unburned boundaries in different landscape settings within interior...
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Fire can be a significant driver of permafrost change in boreal landscapes, altering the availability of soil carbon and nutrients that have important implications for future climate and ecological succession. However, not all landscapes are equally susceptible to fire-induced change. As fire frequency is expected to increase in the high latitudes, methods to understand the vulnerability and resilience of different landscapes to permafrost degradation are needed. Geophysical and other field observations reveal details of both near-surface (less than 1 m) and deeper (greater than 1 m) impacts of fire on permafrost along 14 transects that span burned-unburned boundaries in different landscape settings within interior...
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Fire can be a significant driver of permafrost change in boreal landscapes, altering the availability of soil carbon and nutrients that have important implications for future climate and ecological succession. However, not all landscapes are equally susceptible to fire-induced change. As fire frequency is expected to increase in the high latitudes, methods to understand the vulnerability and resilience of different landscapes to permafrost degradation are needed. Geophysical and other field observations reveal details of both near-surface (less than 1 m) and deeper (greater than 1 m) impacts of fire on permafrost along 14 transects that span burned-unburned boundaries in different landscape settings within interior...
Borehole nuclear magnetic resonance (NMR) data were collected by the U.S. Geological Survey (USGS) at Big Trail Lake, a thermokarst lake outside of Fairbanks, Alaska, to quantify unfrozen water content and soil properties at select sites in and around the lake edge. In September 2019, NMR data were collected within two 2.3 m deep boreholes adjacent to the East and North perpendicular electrical resistivity survey lines. Manual permafrost-probe measurements of thaw depths were also collected. These two boreholes were logged a second time in late March 2020. Additional one-time NMR measurements of liquid water content were collected in September 2019 within the lakebed sediments (0-25 cm depth) in approximately 2.5...
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Electrical resistivity tomography (ERT), downhole nuclear magnetic resonance (NMR), and manual permafrost-probe measurements were used to quantify permafrost characteristics along transects within several catchments in interior Alaska in late summer 2016 and 2017. Geophysical sites were chosen to coincide with additional soil, hydrologic, and geochemical measurements adjacent to various low-order streams and tributaries in a mix of burned and unburned watersheds in both silty and rocky environments. Data were collected in support of the Striegl-01 NASA ABoVE project, "Vulnerability of inland waters and the aquatic carbon cycle to changing permafrost and climate across boreal northwestern North America." Additional...
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Electrical resistivity tomography (ERT), downhole nuclear magnetic resonance (NMR), and manual permafrost-probe measurements were used to quantify permafrost characteristics along transects within several catchments in interior Alaska in late summer 2016 and 2017. Geophysical sites were chosen to coincide with additional soil, hydrologic, and geochemical measurements adjacent to various low-order streams and tributaries in a mix of burned and unburned watersheds in both silty and rocky environments. Data were collected in support of the Striegl-01 NASA ABoVE project, "Vulnerability of inland waters and the aquatic carbon cycle to changing permafrost and climate across boreal northwestern North America." Additional...
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Electrical resistivity tomography (ERT), downhole nuclear magnetic resonance (NMR), and manual permafrost-probe measurements were used to quantify permafrost characteristics along transects within several catchments in interior Alaska in late summer 2016 and 2017. Geophysical sites were chosen to coincide with additional soil, hydrologic, and geochemical measurements adjacent to various low-order streams and tributaries in a mix of burned and unburned watersheds in both silty and rocky environments. Data were collected in support of the Striegl-01 NASA ABoVE project, "Vulnerability of inland waters and the aquatic carbon cycle to changing permafrost and climate across boreal northwestern North America." Additional...
Carbon release from thawing permafrost soils could significantly exacerbate global warming as the active-layer deepens, exposing more carbon to decay. Plant community and soil properties provide a major control on this by influencing the maximum depth of thaw each summer (active-layer thickness; ALT), but a quantitative understanding of the relative importance of plant and soil characteristics, and their interactions in determine ALTs, is currently lacking. To address this, we undertook an extensive survey of multiple vegetation and edaphic characteristics and ALTs across multiple plots in four field sites within boreal forest in the discontinuous permafrost zone (NWT, Canada). Our sites included mature black spruce,...
Geophysical measurements and related field data were collected by the U.S. Geological Survey (USGS) at the Alaska Peatland Experiment (APEX) site in Interior Alaska from 2018 to 2020 to characterize subsurface thermal and hydrologic conditions along a permafrost thaw gradient. The APEX site is managed by the Bonanza Creek LTER (Long Term Ecological Research). Nine instrument sites were established in April 2018 and initially comprised a buried seismic station for continuous passive recording of the seismic wavefield, and seven of the nine sites were given a borehole for repeat nuclear magnetic resonance (NMR) logging. Between June 2018 and September 2019, measurements of active-layer thaw depth were regularly recorded...
Geophysical measurements and related field data were collected by the U.S. Geological Survey (USGS) at the Alaska Peatland Experiment (APEX) site in Interior Alaska from 2018 to 2020 to characterize subsurface thermal and hydrologic conditions along a permafrost thaw gradient. The APEX site is managed by the Bonanza Creek LTER (Long Term Ecological Research). Nine instrument sites were established in April 2018, seven of which were given a borehole approximately 2.3 meters (m) deep for repeat nuclear magnetic resonance (NMR) logging to quantify unfrozen water content and soil properties in the near surface. NMR data were collected from each borehole a total of ten times between April 2018 and October 2020, at a...
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Fire can be a significant driver of permafrost change in boreal landscapes, altering the availability of soil carbon and nutrients that have important implications for future climate and ecological succession. However, not all landscapes are equally susceptible to fire-induced change. As fire frequency is expected to increase in the high latitudes, methods to understand the vulnerability and resilience of different landscapes to permafrost degradation are needed. Geophysical and other field observations reveal details of both near-surface (less than 1 m) and deeper (greater than 1 m) impacts of fire on permafrost along 14 transects that span burned-unburned boundaries in different landscape settings within interior...
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Electrical resistivity tomography (ERT), downhole nuclear magnetic resonance (NMR), and manual permafrost-probe measurements were used to quantify permafrost characteristics along transects within several catchments in interior Alaska in late summer 2016 and 2017. Geophysical sites were chosen to coincide with additional soil, hydrologic, and geochemical measurements adjacent to various low-order streams and tributaries in a mix of burned and unburned watersheds in both silty and rocky environments. Data were collected in support of the Striegl-01 NASA ABoVE project, "Vulnerability of inland waters and the aquatic carbon cycle to changing permafrost and climate across boreal northwestern North America." Additional...
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Electrical resistivity tomography (ERT), downhole nuclear magnetic resonance (NMR), and manual permafrost-probe measurements were used to quantify permafrost characteristics along transects within several catchments in interior Alaska in late summer 2016 and 2017. Geophysical sites were chosen to coincide with additional soil, hydrologic, and geochemical measurements adjacent to various low-order streams and tributaries in a mix of burned and unburned watersheds in both silty and rocky environments. Data were collected in support of the Striegl-01 NASA ABoVE project, "Vulnerability of inland waters and the aquatic carbon cycle to changing permafrost and climate across boreal northwestern North America." Additional...
Geophysical measurements were collected by the U.S. Geological Survey (USGS) at two sites in Interior Alaska in 2019 and 2020 for the purposes of imaging permafrost structure and quantifying variations in subsurface moisture content in relation to thaw features. In September 2019, electrical resistivity tomography (ERT) and downhole nuclear magnetic resonance (NMR) data were used to quantify permafrost characteristics across the shorelines of Big Trail Lake, a thermokarst lake outside of Fairbanks, Alaska. Three 222 m ERT survey lines were collected perpendicular to the North, East, and South shorelines, and two 110 m lines were collected parallel to the southeast and northeast shorelines. Models of electrical resistivity...
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Geophysical measurements were collected by the U.S. Geological Survey (USGS) at five sites in Interior Alaska in September 2021 for the purposes of imaging permafrost structure and quantifying variations in subsurface moisture content in relation to thaw features. Electrical resistivity tomography (ERT) measurements were made along transects 110 - 222 m in length to quantify subsurface permafrost characteristics. ERT transects were collected across a fireline boundary within the Bonanza Creek Long Term Ecological Research (LTER) site where repeat measurements have been made since 2014; across and adjacent to two thermokarst lakes, Vault Lake and Goldstream Lake; and along two profiles at the North Star golf course...
map background search result map search result map Fire impacts on permafrost in Alaska: Geophysical and other field data collected in 2015 Borehole Nuclear Magnetic Resonance Data; Alaska, 2015 final Borehole Nuclear Magnetic Resonance Inverted Models; Alaska, 2015 Electrical Resistivity Tomography Inverted Models; Alaska, 2015 Permafrost Soil Measurements; Alaska, 2015 Permafrost Vegetation Measurements; Alaska, 2015 Alaska permafrost characterization: Geophysical and related field data collected from 2016-2017 Electrical Resistivity Tomography Data collected in Alaska 2016-2017 Electrical Resistivity Tomography Inverted Models Alaska 2016-2017 Borehole Nuclear Magnetic Resonance Data Collected in Alaska 2016-2017 Permafrost Soil Measurements in Alaska 2016-2017 Alaska permafrost characterization: Geophysical and related field data collected from 2019-2020 Alaska permafrost characterization: Borehole Nuclear Magnetic Resonance Data & Models from 2019-2020 Alaska permafrost characterization: Electrical Resistivity Tomography Data & Models from 2019 APEX Borehole Nuclear Magnetic Resonance (NMR) Data and Models from 2018-2020 APEX Thaw Depth Data from 2018-2019 Alaska permafrost characterization: Electrical Resistivity Tomography (ERT) data collected in 2021 Alaska permafrost characterization: Borehole Nuclear Magnetic Resonance (NMR) data collected in 2021 Alaska permafrost characterization: Borehole Nuclear Magnetic Resonance Data & Models from 2019-2020 APEX Borehole Nuclear Magnetic Resonance (NMR) Data and Models from 2018-2020 APEX Thaw Depth Data from 2018-2019 Alaska permafrost characterization: Borehole Nuclear Magnetic Resonance (NMR) data collected in 2021 Alaska permafrost characterization: Geophysical and related field data collected from 2019-2020 Alaska permafrost characterization: Electrical Resistivity Tomography Data & Models from 2019 Alaska permafrost characterization: Electrical Resistivity Tomography (ERT) data collected in 2021 Electrical Resistivity Tomography Data collected in Alaska 2016-2017 Electrical Resistivity Tomography Inverted Models Alaska 2016-2017 Permafrost Soil Measurements in Alaska 2016-2017 Borehole Nuclear Magnetic Resonance Data Collected in Alaska 2016-2017 Alaska permafrost characterization: Geophysical and related field data collected from 2016-2017 Borehole Nuclear Magnetic Resonance Data; Alaska, 2015 final Borehole Nuclear Magnetic Resonance Inverted Models; Alaska, 2015 Permafrost Soil Measurements; Alaska, 2015 Permafrost Vegetation Measurements; Alaska, 2015 Fire impacts on permafrost in Alaska: Geophysical and other field data collected in 2015 Electrical Resistivity Tomography Inverted Models; Alaska, 2015