createHwDataframe: Characterize heat waves
Description
This function takes a dataframe with identified heat waves and returns
a dataframe that lists and characterizes all of the heat waves. If no
heat waves were identified in a city, it returns a data frame with the
same columns but no observations, to allow the empty dataframe to be
joined without error to the dataframes for cities that do have heat
waves under the definition.
Usage
createHwDataframe(city, threshold, heatwaves, ensembleSeries, i, global, custom)
Arguments
city
A character vector with the identification of the city
being processed.
threshold
Numeric string with threshold temperature used in
the heat wave definition, in degrees Fahrenheit.
heatwaves
A dataframe with the following columns:
-
date: Date of each observation, in class "Date";
-
tmpd: Temperature in degrees Fahrenheit;
-
hw: A binary variable designating whether a day is in a
heat wave (0: not in a heat wave; 1: in a heat wave); and
-
hw.number: A numeric value, 0 if the day was not part of a
heat wave, otherwise the number of the heat wave to which the day belonged.
This is the format of the output of IDheatwaves.
ensembleSeries
A list object giving the projection time series as
well as a variety of other information for a single ensemble member.
This is the output of processEnsemble. i
An index specifying which city is being processed. This corresponds
to the order of the cities in the citycsv file specified in
gen_hw_set. global
An list object created by gen_hw_set that
includes user specifications (e.g., the path to the output directory, the
path to the input climate projections, the dataframe with city
locations). custom
An list object created by gen_hw_set that
includes user specifications (e.g., the name of the R function to
use to identify heat waves, alternative upper and lower year boundaries
for the data used to determine threshold temperatures for the heat wave
definition, alternative upper and lower year boundaries
for the projection period of the heat wave datasets being generated). Value
A dataframe of identified and characterized heat waves for a single
city and single ensemble member. Each row of this dataframe represents a
heat wave, with the following columns:
- hw.number: A sequential number identifying each heat wave in a city;
- mean.temp: Average daily temperature across all days in the
heat wave, in degrees Fahrenheit;
- max.temp: Highest daily temperature across days in the
heat wave, in degrees Fahrenheit;
- min.temp: Lowest daily temperature across days in the
heat wave, in degrees Fahrenheit
- length: Number of days in the heat wave;
- start.date: Date of the first day of the heat wave;
- end.date: Date of the last day of the heat wave;
- start.doy: Day of the year of the first day of the heat wave
(1 = Jan. 1, etc.);
- start.month: Month in which the heat wave started (1 = January,
etc.);
- days.above.80: Number of days in the heat wave above 80 degrees
Fahrenheit;
- days.above.85: Number of days in the heat wave above 85 degrees
Fahrenheit;
- days.above.90: Number of days in the heat wave above 90 degrees
Fahrenheit;
- days.above.95: Number of days in the heat wave above 90 degrees
Fahrenheit;
- days.above.99th: Number of days in the heat wave above the 99th
percentile temperature for the city, using the period specified
by the user with the
referenceBoundaries argument in
gen_hw_set as a reference for determining these
percentiles;
- days.above.99.5th: Number of days in the heat wave above the 99.5th
percentile temperature for the city, using the period specified
by the user with the
referenceBoundaries argument in
gen_hw_set as a reference for determining these
percentiles;
- first.in.season: Whether the heat wave was the first to occur in its
calendar year (Note: this characteristic is likely not useful in
southern hemisphere studies.);
- threshold.temp: The temperature used as the threshold for the
heat wave definition in the city;
- mean.temp.quantile: The percentile of the average daily mean
temperature during the heat wave compared to the city's year-round
temperature distribution, based on the temperatures for the city
during the period specified by the
referenceBoundaries
argument in gen_hw_set;
- max.temp.quantile: The percentile of the highest daily mean
temperature during the heat wave compared to the city's year-round
temperature distribution;
- min.temp.quantile: The percentile of the lowest daily mean
temperature during the heat wave compared to the city's year-round
temperature distribution;
- mean.temp.1: The city's average year-round temperature, based
on the temperatures for the city during the period specified by
the
referenceBoundaries argument in
gen_hw_set;
- mean.summer.temp: The city's average May--September
temperature, based on the temperatures for the city during the
period specified by the
referenceBoundaries argument
in gen_hw_set; and
- city: The identifier for the city, as given in the file
specified in the
citycsv argument of
gen_hw_set.