Data from: Cross-scale regulation of seasonal microclimate by
vegetation and snow in the Arctic tundra
ReadMe for cleaned datasets used in analyses
Associated publication:
von Oppen, J., Assmann, J.J., Bjorkman, A.D., Treier, U.A., Elberling,
B., Nabe-Nielsen, J., & Normand, S. (2022) Cross-scale regulation of
seasonal microclimate by vegetation and snow in the Arctic tundra.
Global Change Biology
Description
The files contain data used in the analyses for von Oppen et
al. (2022) Global Change Biology. See also the ReadMe in the
root directory (ReadMe.Rmd), as well as
scripts/data_cleaning.R and scripts/analyses.R for
data cleaning and analysis workflows, respectively. Access through the R
project file provided in the root directory (e.g. with RStudio) is
recommended for seamless running of the code. Please see the paper (link
in the zenodo
archive) for methodological details, results and discussion.
Files
This directory data/plot_data/processed contains several
datasets that share a similar structure and many of the same variables,
yet are aggregated at different temporal resolution:
- microclim_plot_data_complete.csv: data at plot level at
study period resolution, i.e. one observation per study
plot. Temperature values are aggregated across the whole available time
period (e.g., growing season for TMS data) or as specified in the
variable names
- microclim_plot_data_complete_season19/ndjfm1920.csv: data
at plot level at daily resolution, i.e. one observation
per day per study plot. Temperature values are aggregated daily
(according to WGST time zone)
Variables
Variable name [format]
- plot_id [chr]
- date [Date, YYYY-MM-DD]
- tms/hobo_id [int]: logger identifier
- lat/lon [num]: plot coordinates in WGS84
- elevation [num]: plot elevation in masl
- sector [chr]: mountain slope (= region; east = e /
west = w) + elevation band (elev_band; 1-5) of the respective
plot location
- aspect/slope [int]: plot exposition / slope inclination in
°
- sri_daily/season19/ndjfm1920 [num]: Solar Radiation Index
(Keating et al. 2007) for
each date / integrated over growing season / winter season,
respectively
- *topo_prim(_num)/topo_sec* [chr/int]: topography/landform
classification of the study plot location. 1 = snowbed, 2 = depression,
3 = flat, 4 = slope, 5 = ridge (num = numeric)
- tms_moist_vol_mean/min/max/amp_scaled [num]: growing-season
mean daily mean/minimum/maximum/amplitude of soil moisture. Raw readings
were calibrated based on in situ soil particle size samples (see
*scripts/data_cleaning.R). Before calculating seasonal means, daily
values were scaled between 0 and 1 to conserve relative differences
between plots while avoiding negative values due to suboptimal
calibration in single plots
- ndays_snowcover_ndjfm [int]: no. snow-covered days as
inferred from soil temperature measurements
- soil_depth_avg [num]: soil depth in cm, averaged from four
vertical probing measurements taken at 50 cm distance from the plot
centre in semi-cardinal directions
- peg_height [num]: maximum vertical height of the peg
marking the plot centre
- tms_shield_height_avg [num]: height of the top shield of
the TMS logger, averaged from four vertical measurements taken at all
cardinal directions
- tms_substrate [chr]: subjective classification of the
substrate the TMS logger was located in
- cover_tms/hobo_top/low/ground [num]: vegetation cover
estimate in %, within a circle of 5 cm radius at the location of the
TMS/HOBO logger, at height of the top and bottom TMS shield and at the
ground surface, respectively
- veg_height_avg/max_tms/hobo [num]: average/maximum
vegetation height at the TMS/HOBO logger, measured vertically four times
across cardinal directions
- date_setup/survey/tms_/hobo_retrieval [POSIXct, YYYY-MM-DD
hh:mm:ss]: date of plot establishment, vegetation survey, TMS or HOBO
logger retrieval, respectively, in UTC (2am = 12am in WGST)
- researcher/photo_id/comment_setup/survey/retrieval
- time_tms/hobo_retrieval [num, hh:mm:ss]: specific time of
TMS/HOBO logger retrieval
- tms/hobo_logger_make/model [chr]: manufacturer/model of
loggers
- tms_T1/2/3/hobo_depth/height [int]: depth/height of logger
sensors in cm relative to ground surface level
- cov_{type}_{radius} [num]: % cover estimates for the
following plant functional types/cover categories across the different
sample plot sizes: shrubs, forbs, graminoids, bryophytes, sphagnum moss,
lichen, cyanobacteria/biocrust, rocks (>2 cm diameter), bare
ground/soil (<2 cm), litter, vascular plants (= shrubs + forbs +
graminoids), open surface (= rocks + bare ground)
- veg_height_avg_{radius} [num]: average vegetation height
across the different sample plot sizes
- plant_div_{radius} [int]: number of plant species found in
the different sample plot sizes
- plot-level temperature and soil moisture variables: see
below
- min_diff_station [chr]: ID of automated weather station
with least elevational difference to each study plot (= paired
station)
Daily temperature and soil moisture variables
Daily temperature amd soil moisture variables available differ
between study periods, due to different deployment periods (TMS only
during growing season).
In microclim_plot_data_complete_ndjfm1920.csv (winter
season):
- hobo_temp_mean/min/max [num]: daily mean/minimum/maximum
soil temperatures for HOBO sensors across the winter season (November –
March)
- station_pair_daily_mean/min/max_tamp [num]: daily
mean/minimum/maximum free-air temperature from paired automated
weather station (to calculate vertical temperature differences)
- station_base_daily_mean/min/max_tamp [num]: daily
mean/minimum/maximum free-air temperature from lowest automated weather
station (for macroclimate reference temperatures)
- hobo_dT4hobo_mean/min/max [num]: difference in daily
mean/minimum/maximum temperatures between soil (HOBO) and paired
free-air weather station (‘T4’) sensors. Differences are calculated as
lower – higher layer. Example: dT4hobo_mean = daily mean soil – daily
mean free-air temperature
In microclim_plot_data_complete_season19.csv (growing
season):
- tms_T1/2/3_mean/min/max [num]: daily mean/minimum/maximum
temperatures for TMS sensors in soil (T1), at near-surface (T2) and
canopy height(T3) level, across the growing season
- hobo_temp_mean/min/max [num]: daily mean/minimum/maximum
soil temperatures for HOBO sensors across the growing season
- station_pair_daily_mean/min/max_tamp [num]: daily
mean/minimum/maximum free-air temperature from paired automated
weather station (to calculate vertical temperature differences)
- station_base_daily_mean/min/max_tamp [num]: daily
mean/minimum/maximum free-air temperature from lowest automated weather
station (for macroclimate reference temperatures)
- tms_d{sensor comparison pair}_mean/min/max [num]:
difference in daily mean/minimum/maximum temperatures between two
sensors (T1 = TMS soil, T2 = TMS near-surface, T3 = TMS canopy-layer, T4
= weather station free-air, hobo = HOBO). Differences are calculated as
lower – higher layer. Example: dT3T1_mean = daily mean soil – daily mean
canopy-layer temperature; dT4T3_max = daily maximum canopy-layer – daily
maximum free-air temperature
- soil_class_TOMST [chr]: soil class used for calibration of
soil moisture curves. Soil classes and calibration curves were provided
by the manufacturer – see Appendix A in Wild et
al. (2019) for available soil types and calibration curves
- *tms_moist_vol_daily_mean/min/max/amp(_scaled)* [num]: original and
scaled calibrated daily mean/minimum/maximum/amplitude of volumetric
soil moisture