Landscape Albedo in Taylor Valley, Antarctica from 2015 to 2019

This data package contains reflectance data and associated aerial images collected using a helicopter-suspended "albedo box," in which a shortwave radiometer and camera where mounted facing downward. The purpose of this study was to measure how surface reflectance varies within and across landscape types (glaciers, lakes, and soils) over the course of a single field season as well as across multiple field seasons. We made five flights in the 2015-2016 field season (20 November 2015, 7 December 2015, 24 December 2015, 5 January 2016, and 12 January 2016), five flights in the 2016-2017 field season (11 November 2016, 3 December 2016, 14 December 2016, 3 January 2017, 23 January 2017), four flights in the 2017-2018 field season (22 November 2017, 7 December 2017, 27 December 2017, 13 January 2018), and two flights in the 2018-2019 field season (23 November 2018, 9 January 2019). Flights originated from Lake Hoare field camp, flew down-valley over Canada Glacier, Lake Fryxell, and Commonwealth Glacier, then turned around and flew up-valley to Taylor Glacier Meteorological Station, after which they returned to Lake Hoare field camp. Flights took roughly one hour and were flown at approximately 25.72 m s-1 (50 knots) and 91.44 m (300 ft) above the ground surface. These data can be normalized to incoming solar radiation (measured in-situ at meteorological stations) to calculate landscape albedo. When collected several times throughout a season, these results can show how snow distribution and physical changes to glacier and lake ice impact the amount of incoming radiation that is absorbed, while also tracking the influence of deposited sediment on ice surfaces. Moreover, these data are important for quantifying the long-term changes in energy connectivity between the atmosphere and the landscape (i.e., addressing Hypothesis 1 of the MCM V funding cycle).

Data Policies This data package is released under the Creative Commons Attribution 4.0 International License (CC BY 4.0; http://creativecommons.org/licenses/by/4.0/), which allows consumers (hereinafter referred to as “Data Users”) to freely reuse, redistribute, transform, or build on this work (even commercially) so long as appropriate credit is provided. Accordingly, Data Users are required to properly cite this data package in any publications or in the metadata of any derived products that result from its use (in whole or in part). A recommended citation is provided on the summary metadata page associated with this data package in the McMurdo Dry Valleys LTER Data Catalog (https://mcmlter.org/data), and a generic citation may be found on the summary metadata page in the repository where this data package was obtained. When these data contribute significantly to the contents of a publication, Data Users must also acknowledge that data were provided by the NSF-supported McMurdo Dry Valleys Long Term Ecological Research program (OPP-2224760). This data package has been released in the spirit of open scientific collaboration. Hence, Data Users are strongly encouraged to consider consultation, collaboration, and/or co-authorship (as appropriate) with the data package creator(s). Data Users should be aware these data may be actively used by others for ongoing research; thus, coordination may be necessary to prevent duplicate publication. Data Users should also recognize that misinterpretation of data may occur if they are used outside the context of the original study. Hence, Data Users are urged to contact the data package creator(s) if they have any questions regarding methodology or results. While substantial efforts are made to ensure the accuracy of this data package (with all its components), complete accuracy cannot be guaranteed. Periodic updates to this data package may occur, and it is the responsibility of Data Users to check for new versions. This data package is made available “as is” and comes with no warranty of accuracy or fitness for use. The creator(s) of this data package and the repository where these data were obtained shall not be liable for any damages resulting from misinterpretation, use, or misuse of these data. Finally, as a professional courtesy, we kindly request Data Users notify the primary contact referenced in the metadata when these data are used in the production of any derivative work or publication. Notification should include an explanation of how the data were used, along with a digital copy of the derived product(s). Thank you.

Data were collected by helicopter using instruments mounted to a weighted box with a fin to reduce swing in-flight (i.e., an "albedo box"). A shortwave radiometer (CMP3, Kipp and Zonen) was mounted to point down at the valley floor. Additionally, a downward facing camera (CC5MPX, Campbell Scientific) was mounted next to the radiometer. A GPS unit (GPS16X-HVS, manufactured by Garmin for Campbell Scientific) was fixed to the top of the box. All instruments were wired in to a data logger (CR1000, Campbell Scientific) and programmed to collect data every three seconds. Before each flight, the radiometer and camera lens were cleaned. The albedo box was attached to a helicopter with a 6.1 m (20 ft) lead line. Data were downloaded and archived after each flight. Due to a hardware failure, images captured during the two 2018-2019 season flights were not recorded, and therefore these images are not included in the data package. Flights spanned the entire Taylor Valley and were routed over glaciers originating from the Asgard Range, the major lakes, and Taylor Glacier. Pilots were instructed to fly at 91.44 m (300 ft) off the ground and at a speed of 25.72 m s-1 (50 knots). Flights occurred on completely cloud free days or homogeneously cloudy days ensure there was no variability in incoming radiation across the Valley.