Daniel McGrath

Colorado State University | Assistant Professor

Subject Areas: glaciology, snow hydrology, cryosphere

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ABSTRACT:

This data is from the 2021-22 water year within the Cameron Peak wildfire persistent snow zone study area. The collection of data includes both continuous (hourly automated weather station; daily camera and sonic snow depth) and repeat in situ (snow depth transects, snow pits, and albedo) measurements collected between 1 October 2021 and 1 September 2022. Specific information for how each each of the datasets was collected is included in the methods document.

Abstract from the paper:
Increasing wildfire frequency and severity in high-elevation seasonal snow zones presents a considerable water resource management challenge across the western U.S. Wildfires can affect snowpack accumulation and melt patterns, altering the quantity and timing of runoff. While prior research has shown that wildfire generally increases snow melt rates and advances snow disappearance dates, uncertainties remain regarding variations across complex terrain and the energy balance between burned and unburned areas. Utilizing multiple paired in-situ data sources within the 2020 Cameron Peak burn area on the Front Range of Colorado, USA, during the 2021–2022 winter, we found no significant difference in peak snow water equivalent (SWE) magnitude between burned and unburned areas. However, the burned south aspect reached peak SWE 22 days earlier than burned north. During the ablation period, burned south melt rates were 71% faster than unburned south melt rates, whereas burned north melt rates were 94% faster than unburned north aspects. Snow disappeared 7–11 days earlier in burned areas than unburned areas. Net energy differences at the burned and unburned automated weather station sites were seasonally variable, as the burned area had a more negative net energy balance during the winter (snowpack lost energy), but gained significantly more net energy during the spring (snowpack warms faster). Net shortwave radiation was 1.5x greater at the burned area during the winter (1 December–28 February) and over 2x greater during the spring (1 March–31 May). Increased incoming shortwave radiation was 6x more impactful in altering the net shortwave radiation than the decreases in surface albedo. These findings emphasize the need for post-wildfire water resource planning that accounts for aspect-dependent differences in energy and mass balance to accurately predict snowpack storage and runoff timing.

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ABSTRACT:

This resource includes field observations collected during the NASA SnowEx21 campaign at Cameron Pass, Colorado. The observations consist of ground-penetrating radar travel times, snow pit observations of snow density, temperature and permittivity, snow depth observations from a snow probe, and UAV Structure from Motion (SfM) derived surface elevation models. The analysis of these data is presented in McGrath et al. (2022), A time-series of snow density and snow water equivalent observations derived from the integration of GPR and UAV SfM observations, Frontiers in Remote Sensing, doi:10.3389/frsen.2022.886747.

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Ground-penetrating radar, snowpit, probe and UAV-SfM observations from Cameron Pass, Colorado during NASA SnowEx21
Created: March 29, 2022, 7:56 p.m.
Authors: McGrath, Daniel · Randall Bonnell · Lucas Zeller · Alex Olsen-Mikitwicz · Ella Bump

ABSTRACT:

This resource includes field observations collected during the NASA SnowEx21 campaign at Cameron Pass, Colorado. The observations consist of ground-penetrating radar travel times, snow pit observations of snow density, temperature and permittivity, snow depth observations from a snow probe, and UAV Structure from Motion (SfM) derived surface elevation models. The analysis of these data is presented in McGrath et al. (2022), A time-series of snow density and snow water equivalent observations derived from the integration of GPR and UAV SfM observations, Frontiers in Remote Sensing, doi:10.3389/frsen.2022.886747.

Show More
Resource Resource

ABSTRACT:

This data is from the 2021-22 water year within the Cameron Peak wildfire persistent snow zone study area. The collection of data includes both continuous (hourly automated weather station; daily camera and sonic snow depth) and repeat in situ (snow depth transects, snow pits, and albedo) measurements collected between 1 October 2021 and 1 September 2022. Specific information for how each each of the datasets was collected is included in the methods document.

Abstract from the paper:
Increasing wildfire frequency and severity in high-elevation seasonal snow zones presents a considerable water resource management challenge across the western U.S. Wildfires can affect snowpack accumulation and melt patterns, altering the quantity and timing of runoff. While prior research has shown that wildfire generally increases snow melt rates and advances snow disappearance dates, uncertainties remain regarding variations across complex terrain and the energy balance between burned and unburned areas. Utilizing multiple paired in-situ data sources within the 2020 Cameron Peak burn area on the Front Range of Colorado, USA, during the 2021–2022 winter, we found no significant difference in peak snow water equivalent (SWE) magnitude between burned and unburned areas. However, the burned south aspect reached peak SWE 22 days earlier than burned north. During the ablation period, burned south melt rates were 71% faster than unburned south melt rates, whereas burned north melt rates were 94% faster than unburned north aspects. Snow disappeared 7–11 days earlier in burned areas than unburned areas. Net energy differences at the burned and unburned automated weather station sites were seasonally variable, as the burned area had a more negative net energy balance during the winter (snowpack lost energy), but gained significantly more net energy during the spring (snowpack warms faster). Net shortwave radiation was 1.5x greater at the burned area during the winter (1 December–28 February) and over 2x greater during the spring (1 March–31 May). Increased incoming shortwave radiation was 6x more impactful in altering the net shortwave radiation than the decreases in surface albedo. These findings emphasize the need for post-wildfire water resource planning that accounts for aspect-dependent differences in energy and mass balance to accurately predict snowpack storage and runoff timing.

Show More