dbpf_TSA_GST: Time Series Analysis for GST

In geocryology/PermafrostDB: PermafrostDB

Time Series Analysis for GST

Description

Give a or multiple location names and it returns a list with snow cover start and end dates, a list with RD dates, a list with warming period dates and a list with zero curtain period dates. Furthermore, a plot is made for each location.

Usage

dbpf_TSA_GST(
  con,
  out.path,
  inventory,
  time_b = "1950-01-01 00:00:00+00",
  time_e = "2050-01-01 00:00:00+00",
  v1 = 0.1,
  v2 = 0.3,
  lengthsnow = 5,
  MDr.sd = 0.3,
  v = 0.25,
  tperc = 40,
  sdoutlier = 3,
  sdsteep = 0.75,
  temp = 0.2,
  slopesd = 0.1,
  tempsd = 0.01,
  lengthzc = 2,
  wateryear = 10
)

Arguments

con	connection to PermafrostDB
out.path	Path to directory where the plot should be saved. e.g: "~/Desktop/"
inventory	location names. Can be a dataframe with column $name or a vector
time_b	Begin date for the import. Format: "1950-01-01 00:00:00+00"
time_e	End date for the import. Format: "2050-01-01 00:00:00+00"
v1	Max. daily standard deviation indicating snow for POSITIVE Ground Surface Temperature. Default is 0.1.
v2	Max. daily standard deviation indicating snow for NEGATIVE Ground Surface Temperature. Default is 0.3.
lengthsnow	Number of days that the snow cover should at least have to be selected as a valid snow cover. Default is 5 days
MDr.sd	Threshold for the mean daily standard deviation for a snow period.
v	Threshold zero curtain (if dailymax & dailymin is within +/- v, this day is a zero curtain day) Default: 0.25
tperc	Percentage of the 10-percent-quantile of the winter temperatures that the warming period should at least reach. Default is 40 percent.
sdoutlier	The number implies how many multiples of the standard deviation of the slope are taken to define a threshold. The threshold is used to detect slope outliers.
sdsteep	The number implies what fraction of the standard deviation of the slope is taken to select the steepest part of a warming period.
temp	The temperature boundary whithin the mean agg_avg of a zero curtain period has to be. Default: 0.2 degrees Celsius
slopesd	Fraction of the standard deviation of the slope used as threshold for the slope. Default: 0.1
tempsd	Fraction of the mean daily standard deviation used as threshold for the daily sd. Default: 0.01
lengthzc	Length that a zero curtain period should at least have. Default: 2 days.
wateryear	start month of the water year. Default is 10 (October) according to the USGS.

Details

The parameters can be adjusted. The different parameters are used by different functions.

Value

A list containing dataframes for the snow cover, RD dates, warming period start dates and zero curtain period dates. Each Dataframe has as well the location coordinates, the MAGST, the wateryear for which the MAGST was calculated as well as the number of the number of missing values of a certain water year. Furthermore, a plot is saved as a pdf file in the assigned directory.

Author(s)

Thomas Knecht <[e-mail]>

Examples

## Not run: 
con <- dbpf_con()
locationList <- dbpf_TSA_GST(con, "./", "NGO-DD-1004_ST01")

## End(Not run)

geocryology/PermafrostDB documentation built on April 17, 2025, 11:54 a.m.