The data and results of the PhD thesis "Environmental response to recent changes in the extratropical circulation" by Langhamer (2024) are available under a CC BY 4.0 licence.
There is an aditional respository with a selection of functions which are useful in processing the data:
doi: 10.5281/zenodo.7962016
The data is rearanged by the following directories:¶
/AWS: Contains raw data from the automatic weather station (AWS-Grey.dat). The time is in local time (UTC-3h) and the AWS is located on an island between the central and the eastern branch near the glacier (50.975°S, 73.222°W at 229 m a.s.l.):
- BattV: battery voltage in V
- PTemp_C: logger termperature in °C
- AirTC: air temperature in °C (1.80 m)
- RH: relative humidity in % (1.80 m)
- SlrW_Avg: incoming short wave radiation in W/m² (1.27 m)
- WS_ms_Avg: mean wind velocity in m/s (2.24 m)
- Ws_ms_Max: maximum wind velocity in m/s (2.24 m)
- WindDir_Avg: prevailing wind direction in Deg (2.24 m)
- WindDir_Str: standard deviation of the prevailing wind direction (2.24 m)
- Rain_mm_Tot: precipitation sum in mm (not heated, 1.05 m)
/Cam: Contains the original camera images (/images) used to estimate the ice front position, ice flow velocity and calving flux. The ice-flow velocity and terminus position were estimated using PyTrx (How et al, 2020). The results of the image sequences are stored in the shape files (/Terminus-shp and /Velocity-shp), where the filename indicates the first image of the image pair. The /ReferenceImages directory contains images of the glacier at the location specified in Cam_loc.csv.
/NewCam-All: Includes all images captured by the upper camera
/OldCam-All: Includes all images captured by the lower camera
/ResultsCam: Contains the post-processed data from the Cam directory (Results-Grey.csv). The data are daily averages using linear interpolation:
- Terminus: relative mean ice front position in m
- caling: calving flux in m/s
- calving-error: estimated error of calving flux in m/s
- velocity: ice-flow velocity in m/d
- velocity-error: standard deviation of velocity estimates in m/d
- velocity-sim: functional representation of the ice-flow velocity after Riel et al. (2021)
- 2t: ERA-5 2m Air temperature in °C of the closest grid point
- CSDI: cold spell duration index. The flag is set to 1 when there are at least three consecutive days
- WSDI: warm spell duration index. The flag is set to 1 when there are at least three consecutive days
/Isotopes: Includes water isotope analysis data. Water samples were collected from Schiaparelli Glacier (Isotopes-Schiaparelli.csv) and Grey Glacier and their surroundings (Isotopes-SouthPatagonia.csv):
- date: local time (UTC-3h)
- Mean18o: mean $\delta^{18}$O value of the water sample in promille
- Sd18o: standard deviation of the mean $\delta^{18}$O value in promille
- Mean2h: mean $\delta^{2}$H value of the water sample in promille
- Sd2h: standard deviation of the mean $\delta^{2}$H value in promille
- lat,lon: location of the water sample (latitude and longitude)
- TypeOfWater: classified type of water sample
- average_: gives the average if more water samples from exactly the same location exists
Instrument specifications:¶
camera equipment:
- DSLR camera system: Canon EOS 1200D
- timer: JJC TM-R timer
- power supply: 7.4 V lithium battery pack (12000 mAh)
- location:
- prior to 2019: 51.003°S, 73.220°W, 96 m a.s.l.
- since 2019: 50.993°S, 73.212°W, 287 m a.s.l.
AWS
- air temperature: Campbell CS215-PWS
- precipitation: Young 52203 - tipping bucket
- incoming solar radiation: Campbell CS300-L pyranometer
- wind: wind monitor, R.M. Young, model 05103
- precipitation: tipping bucket rain gauge, R.M. Young, model 52203 (unheated)
- location: 50.975°S, 73.222°W at 229 m a.s.l.
Isotope Results
- Picarro L2130-i Isotopic Water Analyzer: Analyzed at the Isotope Laboratory of the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB) using cavity ring-down spectroscopy. Sampels were linearly corrected and calibrated with International Atomic Energy Agency (IAEA) standards. The accuracy of $\delta^{18}$O is 0.04 $\unicode{x2030}$ and $\delta^{2}$H is 0.14 $\unicode{x2030}$