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2 Remote Sensing Technologies to Directly and Indirectly Measure Permafrost and Permafrost-Related Ecological Characteristics
Pages 11-42

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From page 11...
... Ground- 2.2) .1 Table 2.1 consists of permafrost processes and penetrating radars have been used to map the thickness properties, and Table 2.2 consists of ecological variables of both the active layer, particularly during the winter that are categorized by six permafrost-related research season before the onset of surface melt, and buried ecological categories: climate, topography, geology ice in permafrost during both the winter and summer and soil, hydrology, vegetation and land cover, and (Arcone et al., 2002; Hubbard et al., 2013; Leuschen et al., 2003; Westermann et al., 2010; Yoshikawa et 1  These two tables are not comprehensive; rather they serve as al., 2006)
From page 12...
... ; remote Of the more than 60 permafrost and related sensing technologies that may become available in ecological variables that were discussed during the the future (the fifth column) ; the available (the sixth workshop, those listed in Box 2.1 emerged as havcolumn)
From page 13...
... . The term "active layer" is most commonly used degrees, depending on the liquid water content, layerto describe a seasonally thawed layer above permafrost ing structure, and texture of soils.
From page 14...
... have shown the potential for this capability. many other characteristics of the active layer, such as Additionally, the airborne electromagnetic (AEM)
From page 15...
... An algorithm was developed to estimate long-term average ALT using thaw-season surface subsidence derived from spaceborne InSAR measurements. The algorithm uses a model of vertical distribution of water content within the active layer accounting for soil texture, organic matter, and moisture.
From page 16...
... . The presence affect the physical and biogeochemical properties of the of ground ice makes permafrost a unique component in subsurface substrate.
From page 17...
... ticipants noted that the required horizontal resolution Several workshop participants indicated that a depends on the scale of investigation. For circumpolar horizontal resolution of 1 to 10 m is sufficient for this mapping, a resolution of several hundred meters would permafrost characteristic.
From page 18...
... are strongly in relation to understanding permafrost extent and altered when transitioning between frozen and thawed surface and subsurface hydrology, including thermo- states. In frozen form, soils and vegetation have very karst lake dynamics.
From page 19...
... As a source of moisture, precipitation is it into topographic and biological crevices. Modeling also an important driver for the evolution of permafrost can estimate snow depth from snow-covered areas, but and ground ice.
From page 20...
... ranges from about 30 to Topography 100 m and vertical resolution from 10 to 15 m. For air borne InSAR DEMs, the horizontal resolution ranged Surface topography.
From page 21...
... subsidence trends near Deadhorse, Alaska (top)
From page 22...
... . also provide information on subsurface stratigraphy, For developing regional maps of topography, many but interpretation is dependent on adequate borehole participants indicated that it would be desirable to have reference data and surficial geology (Minsley et al., 1 to 10 m horizontal resolution; the higher resolution 2012; Van Dam, 2012)
From page 23...
... Properties such as moss thickMost investigations have used optical imagery, such ness, moisture content, and thermal conductivity are as SPOT HRV and AVIRIS hyperspectral data, for similar to organic layer properties in their importance quantifying bare soil properties or inferring soil proper- to understanding permafrost distribution and dynamties from vegetation spectral responses (Barnes et al., ics. Spectral reflectance characteristics have been used 2003)
From page 24...
... Heat transferred Surface water bodies. Many workshop participants 7  LIDARs designed for mapping underwater use a blue-green noted that thermokarst lakes and ponds are important laser that can penetrate water and provide returns of underwater indicators of permafrost degradation.
From page 25...
... In contrast to passive microwave radiometers SAR data acquired at spatial resolutions of ~3-100 m and scatterometers that provide surface soil moisture and at weekly to monthly time scales are suitable for information at low spatial resolution (i.e., tens of km) , monitoring the evolution of floating ice and bedfast ice some participants noted that SAR instruments (i.e., for lakes of various sizes.
From page 26...
... of soil moisture become as or more important than the absolute value of the soil moisture at every point. Many participants indicated that spaceborne or airborne microwave instruments that provide weekly acquisitions at spatial resolutions of 100 m or better and have a vertical sensitivity to the top 10 cm of the soil moisture profile (i.e., vertical resolution)
From page 27...
... , surface hydrology, and other lakes) , satellite acquisitions with spatial resolutions of key variables (e.g., surface temperature, snow cover the order of ~30-100 m and daily revisits would be and depth, active layer dynamics)
From page 28...
... . Many worksoil organic matter and thermal properties, evapotrans- shop participants indicated that a vertical resolution piration and water balance, and snow cover (Jorgenson of 5 cm and a horizontal resolution of 10-30 m are et al., 2010)
From page 29...
... , were acquired by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour.
From page 30...
... A future the Tropospheric Emissions Spectrometer onboard the LiDAR mission to provide coincident vegetation cover, Aura satellite and can be used to trace the large-scale structure, and other high-resolution surface variables, movement of water vapor parcels, globally. Water vapor such as subcanopy topography, is considered desirable isotopes have also been successfully measured in situ by many workshop participants.
From page 31...
... . Because permafrost responds large data stacks and multiparameter fusion, said some to a wide range of ecological factors and is covered by participants, should be extended to include remotely surface vegetation and by soil within the active layer, it sensed field-calibrated SAR-derived surface soil moisis increasingly apparent that no single sensor is capable ture and active layer freeze thaw, SAR and optically of reliably mapping permafrost properties.
From page 32...
... . ground ice (Jorgenson et al., 2008; Kanevskiy et al., Many workshop participants noted that incorporation 2011; Kreig, 1977)
From page 34...
... in InSAR subsidence sensitivity Current is adequate, mode; simultaneous AirMOSS: 30 m especially if used in AirMOSS+UAVSAR horizontal resolution combination (P- and L-band and 5-10 cm vertical SAR) sensitivity SPOT 1, HRV, AVHRR: 1 km MLA, AVHRR Ground ice Thermokarst GPR Quickbird, Direct detection of 1-10 m (commercial 1-10 m is sufficient Grosse et al., 2005; (volume and landforms IKONOS, ground ice, remote satellite)
From page 35...
... b (~2-3-week repeat) Circumpolar: 100 m Times series of radar/ passive and active space based & radiometer airborne GPR & EM SMAPa multifrequency active passive microwave sensors Permafrost thickness Lakes AEM Any optical sensors Satellite-based EM Horizontal: 50-300 Improved <2 m near- Minsley et al., 2012 and 3D geometry Land cover type GPR(VHF and GPR m surface resolution (weakly linked)
From page 36...
... What spatial and temporal What spatial resolutions and temporal Ecological Current systems Prototype sensors are available resolutions are Permafrost-related indicators of this that can measure Current systems that can measure and future (including needed (including ecological variables variable this variable ecological indicators possibilities coverage) coverage)
From page 37...
... Landforms LiDAR/SAR (proposed) Patterned ground synergy ICESatc-ATLAS Longer-term Land cover type LiDAR Various/multisensor US L-band SAR Vertical: <15 cm Horizontal: 1 m Chen et al., 2013; surface subsidence Drainage patterns Tandem-X DLR-JAXA Horizontal: 1 m Vertical: 1-10 cm Liu et al., 2012 Water bodies (World DEM)
From page 38...
... What spatial and temporal What spatial resolutions and temporal Ecological Current systems Prototype sensors are available resolutions are Permafrost-related indicators of this that can measure Current systems that can measure and future (including needed (including ecological variables variable this variable ecological indicators possibilities coverage) coverage)
From page 39...
... 300 m m near-surface Farifteh et al., 2006; Vertical: 2-20 m resolution Fitterman and (for AEM) Deszcz-Pan, 1998; Paine and Minty, 2005 Floating mats in Water bodies Ground GPR High-resolution optical satellite HYspIRI 1-5 m Local scale: 1-5 m Cho et al., 2008; water bodies Topography sensors not applicable to Jorgenson et al., (depth, width)
From page 40...
... What spatial and temporal What spatial resolutions and temporal Ecological Current systems Prototype sensors are available resolutions are Permafrost-related indicators of this that can measure Current systems that can measure and future (including needed (including ecological variables variable this variable ecological indicators possibilities coverage) coverage)
From page 41...
... (methane trapped in ice) Water vapor flux Vegetation Concentrations Concentrations currently measured by Probably 10 km (model 10 m to 1 km Groves and Francis, Water bodies currently measured MODIS, GOES, POES, SNPP in need product output)
From page 42...
... What spatial and temporal What spatial resolutions and temporal Ecological Current systems Prototype sensors are available resolutions are Permafrost-related indicators of this that can measure Current systems that can measure and future (including needed (including ecological variables variable this variable ecological indicators possibilities coverage) coverage)


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