Package 'NEONiso'

Title: Tools to Calibrate and Work with NEON Atmospheric Isotope Data
Description: Functions for downloading, calibrating, and analyzing atmospheric isotope data bundled into the eddy covariance data products of the National Ecological Observatory Network (NEON) <https://www.neonscience.org>. Calibration tools are provided for carbon and water isotope products. Carbon isotope calibration details are found in Fiorella et al. (2021) <doi:10.1029/2020JG005862>, and the readme file at <https://github.com/lanl/NEONiso>. Tools for calibrating water isotope products have been added as of 0.6.0, but have known deficiencies and should be considered very experimental currently.
Authors: Rich Fiorella [aut, cre]
Maintainer: Rich Fiorella <[email protected]>
License: GPL-3
Version: 0.7.0
Built: 2024-11-12 05:57:52 UTC
Source: https://github.com/lanl/neoniso

Help Index


calculate_12CO2

Description

calculate_12CO2

Usage

calculate_12CO2(total_co2, delta13c, f = 0.00474)

Arguments

total_co2

Vector of CO2 mole fractions.

delta13c

Vector of d13C values.

f

Fraction of CO2 that is not 12CO2 or 13CO2. Assumed fixed at 0.00474

Value

Vector of 12CO2 mole fractions.

Author(s)

Rich Fiorella [email protected]

Examples

calculate_12CO2(total_co2 = 410, delta13c = -8.5)

calculate_13CO2

Description

calculate_13CO2

Usage

calculate_13CO2(total_co2, delta13c, f = 0.00474)

Arguments

total_co2

Vector of CO2 mole fractions.

delta13c

Vector of d13C values.

f

Fraction of CO2 that is not 12CO2 or 13CO2. Assumed fixed at 0.00474

Value

Vector of 13CO2 mole fractions.

Author(s)

Rich Fiorella [email protected]

Examples

calculate_13CO2(total_co2 = 410, delta13c = -8.5)

calibrate_ambient_carbon_Bowling2003

Description

calibrate_ambient_carbon_Bowling2003

Usage

calibrate_ambient_carbon_Bowling2003(
  amb_data_list,
  caldf,
  site,
  filter_data = TRUE,
  force_to_end = TRUE,
  force_to_beginning = TRUE,
  gap_fill_parameters = FALSE,
  r2_thres = 0.9
)

Arguments

amb_data_list

List containing an ambient d13C dataset. Will include all variables in 000_0x0_xxm. (character)

caldf

Calibration data frame containing gain and offset values for 12C and 13C isotopologues.

site

Four-letter NEON code corresponding to site being processed.

filter_data

Apply median absolute deviation filter from Brock 86 to remove impulse spikes? Inherited from calibrate_ambient_carbon_Bowling2003()

force_to_end

In given month, calibrate ambient data later than last calibration, using the last calibration? (default true)

force_to_beginning

In given month, calibrate ambient data before than first calibration, using the first calibration? (default true)

gap_fill_parameters

Should function attempt to 'gap-fill' across a bad calibration by carrying the last known good calibration forward? Implementation is fairly primitive currently, as it only carries the last known good calibration that's available forward rather than interpolating, etc. Default FALSE.

r2_thres

Minimum r2 value for calibration to be considered "good" and applied to ambient data.

Value

Depends on write_to_file argument. If true, returns nothing to environment; but returns calibrated ambient observations to the output file. If false, returns modified version of amb_data_list that include calibrated ambient data.

Author(s)

Rich Fiorella [email protected]

Function called by calibrate_carbon_bymonth() to apply gain and offset parameters to the ambient datasets (000_0x0_09m and 000_0x0_30m). This function should generally not be used independently, but should be used in coordination with calibrate_carbon_bymonth().


calibrate_ambient_carbon_linreg

Description

calibrate_ambient_carbon_linreg

Usage

calibrate_ambient_carbon_linreg(
  amb_data_list,
  caldf,
  site,
  filter_data = TRUE,
  force_to_end = TRUE,
  force_to_beginning = TRUE,
  gap_fill_parameters = FALSE,
  r2_thres = 0.9
)

Arguments

amb_data_list

List containing an ambient d13C dataset. Will include all variables in 000_0x0_xxm. (character)

caldf

Calibration data frame containing gain and offset values for 12C and 13C isotopologues.

site

Four-letter NEON code corresponding to site being processed.

filter_data

Apply median absolute deviation filter from Brock 86 to remove impulse spikes? Inherited from calibrate_ambient_carbon_linreg

force_to_end

In given month, calibrate ambient data later than last calibration, using the last calibration? (default true)

force_to_beginning

In given month, calibrate ambient data before than first calibration, using the first calibration? (default true)

gap_fill_parameters

Should function attempt to 'gap-fill' across a bad calibration by carrying the last good calibration forward? Implementation is fairly primitive currently, as it only carries the last known good calibration that's available forward rather than interpolating, etc. Default FALSE.

r2_thres

Minimum r2 value for calibration to be considered "good" and applied to ambient data.

Value

Nothing to environment; returns calibrated ambient observations to the function orchestrating calibration (calibrate_carbon). This function is not designed to be called on its own, and is not exported to the namespace.

Author(s)

Rich Fiorella [email protected]

Function called by calibrate_ambient_carbon_linreg to apply gain and offset parameters to the ambient datasets (000_0x0_09m and 000_0x0_30m). This function should generally not be used independently, but should be used with calibrate_ambient_carbon_linreg.


calibrate_ambient_water_isotopes

Description

calibrate_ambient_water_isotopes

Usage

calibrate_ambient_water_linreg(
  amb_data_list,
  caldf,
  outname,
  site,
  filter_data = TRUE,
  force_to_end = TRUE,
  force_to_beginning = TRUE,
  r2_thres = 0.9
)

Arguments

amb_data_list

List containing ambient d18O/d2H datasets. Will include all variables in 000_0x0_xxm. (character)

caldf

Calibration data frame containing slope and intercept values for d18O and d2H values.

outname

Output variable name. Inherited from calibrate_ambient_water_linreg

site

Four-letter NEON code corresponding to site being processed.

filter_data

Apply a median filter to output ambient data? inherited.

force_to_end

In given month, calibrate ambient data later than last calibration, using the last calibration? (default true)

force_to_beginning

In given month, calibrate ambient data before than first calibration, using the first calibration? (default true)

r2_thres

Minimum r2 value for calibration to be considered "good" and applied to ambient data.

Value

Nothing to environment; returns calibrated ambient observations to the output file. This function is not designed to be called on its own.

Author(s)

Rich Fiorella [email protected]

Function called by calibrate_ambient_water_linreg to apply slope and intercept parameters to the ambient datasets (000_0x0_09m and 000_0x0_30m) to correct to the VSMOW scale. This function should generally not be used independently, but should be used with calibrate_ambient_water_linreg. Note that in this version NO CORRECTION FOR HUMIDITY is performed. Use with caution.


calibrate_carbon

Description

[Experimental] This function drives a workflow that reads in NEON carbon isotope data of atmospheric CO2, calibrates it to the VPDB scale, and (optionally) writes the calibrated data to a new HDF5 file. Two different approaches are possible: a) a calibration on 12CO2 and 13CO2 isotopologues independently, after Bowling et al. 2003 (Agr. For. Met.), or b) a direct calibration of d13C and CO2 values using linear regression. Most of the time the results generated are extremely similar to each other. Wen et al. 2013 compared several different carbon isotope calibration techniques and found this to be the superior method under most circumstances. We also found this to be the case for NEON data (Fiorella et al. 2021; JGR-Biogeosciences).

Usage

calibrate_carbon(
  inname,
  outname,
  site,
  method = "Bowling_2003",
  calibration_half_width = 0.5,
  force_cal_to_beginning = TRUE,
  force_cal_to_end = TRUE,
  gap_fill_parameters = FALSE,
  filter_ambient = TRUE,
  r2_thres = 0.95,
  correct_ref_data = TRUE,
  write_to_file = TRUE,
  remove_known_bad_months = TRUE,
  plot_regression_data = FALSE,
  plot_directory = NULL,
  avg = 6,
  min_nobs = NA,
  standards = c("co2Low", "co2Med", "co2High")
)

Arguments

inname

Input file(s) that are to be calibrated. If a single file is given, output will be a single file per site per month. If a list of files corresponding to a timeseries at a given site is provided, will calibrate the whole time series.

outname

Name of the output file. (character)

site

Four letter NEON site code for site being processed. (character)

method

Are we using the Bowling et al. 2003 method ("Bowling_2003") or direct linear regression of d13C and CO2 mole fractions ("linreg")?

calibration_half_width

Determines the period (in days) from which reference data are selected (period is 2*calibration_half_width).

force_cal_to_beginning

Extend first calibration to the beginning of the file? (default true)

force_cal_to_end

Extend last calibration to the end of the file? (default true)

gap_fill_parameters

Should function attempt to 'gap-fill' across a bad calibration by carrying the last good calibration forward? Implementation is fairly primitive currently, as it only carries the last known good calibration that's available forward rather than interpolating, etc. Default FALSE.

filter_ambient

Apply the median absolute deviation filter (Brock 86) to remove impulse spikes in output ambient data? (logical; default true)

r2_thres

Minimum r2 threshold of an "acceptable" calibration. Acts to remove calibration periods where a measurement error makes relationship nonlinear. Default = 0.95

correct_ref_data

NEON has indicated there are a few instances where reported d13C or CO2 reference values are wrong. If set to true, correct known incorrect values. This argument will (hopefully, eventually) go away after NEON has fixed the reference database. Users will be warned prior to removal of this argument.

write_to_file

Write calibrated ambient data to file? (Mostly used for testing)

remove_known_bad_months

There are a few site months with known spectral issues where the isotope ratios are likely unrecoverable. This parameter allows removal of these files, but allows them to remain in archive.

plot_regression_data

Default false; this is useful for diagnostics.

plot_directory

Only used if plot_regression_data is TRUE, but specify where to write out diagnostic plot of regression data.

avg

The averaging interval to extract, in minutes. Default 6.

min_nobs

Minimum number of high-frequency observations to define a peak.

standards

Which reference gases (standards) to use? Default is all, but can pass a subset of "co2Low", "co2Med", and "co2High" as a vector to this argument as well.

Details

The 'linreg' method simply takes measured and reference d13C and CO2 values and generates a transfer function between them using lm(). For the gain-and-offset method, d13C and CO2 values are converted to 12CO2 and 13CO2 mole fractions. Gain and offset parameters are calculated for each isotopologue independently, and are analogous to regression slope and intercepts, but jointly correct for CO2 concentration dependence and place d13C values on the VPDB scale. The gain and offset parameters are defined by:

G=(X2,refX1,ref)/(X2,measX1,meas)G = (X_{2,ref}-X_{1,ref})/(X_{2,meas}-X_{1,meas})

O=X2,refGX2,measO = X_{2,ref}- G X_{2,meas}

Calibrated ambient isotopologues are then given as:

Xcal=XmeasG+OX_{cal} = X_{meas} G + O

Measurements of reference materials were considered "good" if the following conditions were met:

  • Measured CO2 concentrations were within 10 ppm of known "reference" concentrations.

  • Variance of the CO2 concentration in standard peak was < 5 ppm.

  • Measured d13C value must be within 5 per mil of known "reference" d13C value.

The first two criteria are intended to filter out periods where there is a clear issue with the gas delivery system (i.e., nearly empty gas tank, problem with a valve in the manifold, etc.); the third criterion was adopted after visual inspection of data timeseries revealed that often the first standard measurement following an instrument issue had higher-than-expected error. This criterion clips clearly poor values. Selection of these criteria will become a function argument, and therefore customizable, in a future release.

The behavior of this function will be a bit different depending on what is supplied as inname. If a single file is provided, the output will be monthly. However, a list of files corresponding to a site can also be provided, and then a single output file per site will be generated.

Value

Returns nothing to the environment, but creates a new output HDF5 file containing calibrated carbon isotope values.

Author(s)

Rich Fiorella [email protected]

Examples

## Not run: fin <- system.file('extdata',
'NEON.D15.ONAQ.DP4.00200.001.nsae.2019-05.basic.20201020T211037Z.packed.h5',
         package = 'NEONiso', mustWork = TRUE)
calibrate_carbon_bymonth(inname = fin, outname = 'out.h5',
         site = 'ONAQ', write_to_file = FALSE)
calibrate_carbon_bymonth(inname = fin, outname = 'out.h5',
         site = 'ONAQ', method = 'linreg', write_to_file = FALSE)
## End(Not run)

calibrate_water

Description

[Experimental] This function uses NEON validation data to apply drift corrections to measured ambient water isotope ratios. In brief, ambient water isotope ratios are calibrated by generating regressions using reference water measurements bracketing an ambient period. Three reference waters are measured once per day, with several injections per reference water. Due to memory effects, only the last three are used currently to generate calibration equations. Regressions between measured d18O and d2H values and NEON-provisioned known reference values are generated, and used to calibrate the period of ambient measurements between them if the r2 of the regression is greater than a threshold value (by default, this is 0.95). Most of this function deals with selecting the appropriate calibration data and determining calibration quality. This function also contains a wrapper for calibrate_ambient_water_linreg, which calibrates the ambient water data using the calibration parameters generated in this function. This function also copies over data in the qfqm and ucrt hdf5 data groups.

Usage

calibrate_water(
  inname,
  outname,
  site,
  calibration_half_width = 14,
  filter_data = TRUE,
  force_cal_to_beginning = FALSE,
  force_cal_to_end = FALSE,
  r2_thres = 0.95,
  slope_tolerance = 9999,
  correct_ref_data = TRUE,
  write_to_file = TRUE
)

Arguments

inname

Input file(s) that are to be calibrated. If a single file is given, output will be a single file per site per month. If a list of files corresponding to a timeseries at a given site is provided, will calibrate the whole time series.

outname

Name of the output file. (character)

site

Four-letter NEON code for site being processed.

calibration_half_width

Determines the range of standard measurements to use in determining the calibration regression dataset. Creates a moving window that is 2*calibration_half_width days wide. Default is set to 14 for a 28 day moving window.

filter_data

Apply median absolute deviation filter from Brock 86 to remove impulse spikes?

force_cal_to_beginning

Extend first calibration to the beginning of the file?

force_cal_to_end

Extend last calibration to the end of the file?

r2_thres

Minimum r2 threshold of an "acceptable" calibration. Acts to remove calibration periods where a measurement error makes relationship nonlinear. Default = 0.95

slope_tolerance

How different from 1 should we allow 'passing' regression slopes to be? Experimental parameter, off by default (e.g., default slope parameter = 9999)

correct_ref_data

There are a few instances where the reference d18O and d2H values may have been switched, causing very anomalous d-excess values. If TRUE, implement a switch that corrects this issue.

write_to_file

Write calibrated ambient data to file? (Mostly used for testing)

Details

IMPORTANT NOTE Currently this function does not apply a correction for humidity dependence of Picarro isotopic measurements. This is because the data to implement these corrections is not yet publicly available. Caution is suggested when analyzing data at low humidities, below ~5000 ppm, with likely higher biases at lower humidity values.

Additionally, please note that this function is meant to work on all files for a given site at the same time. A more flexible version that can handle all files or monthly files will be added to a future release.

Value

nothing to the workspace, but creates a new output file of calibrated water isotope data.

Author(s)

Rich Fiorella [email protected]


carbon_regression_plots

Description

carbon_regression_plots

Usage

carbon_regression_plots(caldata, plot_filename, method, mtitle)

Arguments

caldata

Data frame corresponding to a specific calibration period.

plot_filename

What should the output file name for diagnostic plot be?

method

Which method are we using? Currently works for gain/offset.

mtitle

Fed from above routine - what should the plot title be?

Value

Nothing to the environment, but a pdf plot to a file.

Author(s)

Rich Fiorella [email protected]


convert_NEONhdf5_to_POSIXct_time

Description

convert_NEONhdf5_to_POSIXct_time

Usage

convert_NEONhdf5_to_POSIXct_time(intime)

Arguments

intime

Vector of datetimes in NEON data files (as string) to convert to POSIXct class

Value

Vector of datetimes from NEON data file now in POSIXct format.

Author(s)

Rich Fiorella [email protected]

Examples

convert_NEONhdf5_to_POSIXct_time("2019-06-01T12:00:00.000Z")

convert_POSIXct_to_NEONhdf5_time

Description

Converts a POSIXct object back to the character format used by NEON in their HDF eddy covariance files. Output format, using strptime syntax, is %Y-%m-%dT%H:%M:%OSZ.

Usage

convert_POSIXct_to_NEONhdf5_time(intime)

Arguments

intime

POSIXct vector to convert to NEON time format.

Value

Returns character version of POSIXct object matching NEON time variable format.

Author(s)

Rich Fiorella [email protected]

Examples

convert_POSIXct_to_NEONhdf5_time(Sys.time())

copy_qfqm_group

Description

copy_qfqm_group

Usage

copy_qfqm_group(data_list, outname, site, file, species)

Arguments

data_list

List of groups to retrieve qfqm data from.

outname

Output filename.

site

Four-letter NEON site code.

file

Input filename.

species

CO2 or H2O? Same function used for both CO2 and H2O isotopes.

Value

Nothing to the workspace, but copies qfqm group from input file to output file.

Author(s)

Rich Fiorella [email protected]


copy_ucrt_group

Description

copy_ucrt_group

Usage

copy_ucrt_group(data_list, outname, site, file, species)

Arguments

data_list

List of groups to retrieve ucrt data from.

outname

Output file name.

site

NEON 4-letter site code.

file

Input file name.

species

H2O or CO2.

Value

Nothing to the workspace, but copies ucrt group from input file to output file.

Author(s)

Rich Fiorella [email protected]


correct_carbon_ref_cval

Description

This ugly function is present out of necessity, and will only exist for as long as it is necessary. It is an internal correction within the NEONiso calibration routines that is required as there are some mismatches between the 'true' isotope reference values and those in the NEON HDF5 files. NEON is working on correcting this, and after it has been corrected, this function has no need to exist and will be immediately deprecated. As a result, this function is fairly messy but there is little incentive to improve it.

Usage

correct_carbon_ref_cval(
  std_frame,
  site,
  omit_already_corrected = TRUE,
  co2_tol = 5,
  d13c_tol = 0.25
)

Arguments

std_frame

Standard data frame to perform swap on.

site

NEON four letter site code.

omit_already_corrected

Should we attempt correction, if it's already been corrected in the raw files.

co2_tol

Tolerance to use to select co2 values that need to be replaced, in ppm. Default = 5 ppm.

d13c_tol

Tolerance to use to select d13C values that need to be replaced, in ppm. Default = 0.25 per mil.

Details

Current sites and time periods affected:

Value

A data.frame, based on std_frame, where NEON-supplied reference values have been corrected if a mismatch has previously been identified.

Author(s)

Rich Fiorella [email protected]


Correct carbon ref output

Description

Correct carbon ref output

Usage

correct_carbon_ref_output(
  std_list,
  site,
  omit_already_corrected = TRUE,
  co2_tol = 5,
  d13c_tol = 0.25,
  ref_gas
)

Arguments

std_list

List containing reference/validation gas measurements.

site

Four-letter NEON site code.

omit_already_corrected

Skip correction if the reference gas values have already been corrected in the files (default TRUE) If you have older versions of the files, you may want to set this to FALSE.

co2_tol

Tolerance used to identify a mismatch in CO2 values. Will correct measured CO2 values within +/- co2_tol within time period identified as having incorrect reference values.

d13c_tol

Tolerance used to identify a mismatch in d13C values. Will correct measured d13C values within +/- d13c_tol within time period identified as having incorrect reference values.

ref_gas

Which reference gas is being corrected? Expects "co2High", "co2Med", or "co2Low"

Value

A version of std_list with corrected reference values.

Author(s)

Rich Fiorella [email protected]


delta_to_R

Description

delta_to_R

Usage

delta_to_R(delta_values, element)

Arguments

delta_values

A vector of isotope ratios in delta notation.

element

Which element to return R values - carbon, oxygen, or hydrogen.

Value

Vector of isotope ratios (R values).

Author(s)

Rich Fiorella [email protected]

Examples

delta_to_R(delta_values = 0, element = 'oxygen') # 2005.2e-6 for VSMOW.

estimate_calibration_error

Description

estimate_calibration_error

Usage

estimate_calibration_error(formula, data)

Arguments

formula

Formula to pass to caret::train to perform cross validation.

data

Data frame to perform cross-validation on.

Author(s)

Rich Fiorella [email protected]


extract_carbon_calibration_data.R

Description

extract_carbon_calibration_data.R

Usage

extract_carbon_cal_data(
  data_list,
  standards = c("co2Low", "co2Med", "co2High")
)

Arguments

data_list

List containing data, from the /*/dp01/data/ group in NEON HDF5 file.

standards

Which reference gases (standards) to use? Default is all, but can pass a subset of "co2Low", "co2Med", and "co2High" as a vector to this argument as well.

Value

Returns data frame of required variables.

Author(s)

Rich Fiorella [email protected]


extract_water_calibration_data

Description

extract_water_calibration_data

Usage

extract_water_calibration_data(data_list)

Arguments

data_list

List containing data, from the /*/dp01/data/ group in NEON HDF5 file.

Value

Returns data frame of required variables.

Author(s)

Rich Fiorella [email protected]


filter_median_Brock86

Description

Median absolute deviation filter of Brock 1986.

Usage

filter_median_brock86(data, width = 7, threshold = 5)

Arguments

data

Vector to filter.

width

Width of filter, in rows.

threshold

Only filter values that are abs(threshold) away from median

Value

Returns filtered vector.

Author(s)

Rich Fiorella [email protected]


fit_carbon_regression

Description

fit_carbon_regression

Usage

fit_carbon_regression(
  ref_data,
  method,
  calibration_half_width,
  plot_regression_data = FALSE,
  plot_dir = "/dev/null",
  site,
  min_nobs = NA
)

Arguments

ref_data

Reference data.frame from which to estimate calibration parameters.

method

Are we using the Bowling et al. 2003 method ("Bowling_2003") or direct linear regression of d13C and CO2 mole fractions ("linreg")?

calibration_half_width

Determines the period (in days) from which reference data are selected (period is 2*calibration_half_width).

plot_regression_data

True or false - should we plot the data used in the regression? Useful for debugging.

plot_dir

If plot_regression_data is true, where should the plots be saved?

site

Needed for regression plots.

min_nobs

Minimum number of high-frequency observations to define a peak.

Value

Returns a data.frame of calibration parameters. If method == "Bowling_2003", then data.frame includes gain and offset parameters for 12CO2 and 13CO2, and r^2 values for each regression. If method == "linreg", then data.frame includes slope, intercept, and r^2 values for d13C and CO2 values.

Author(s)

Rich Fiorella [email protected]


fit_water_regression

Description

fit_water_regression

Usage

fit_water_regression(
  ref_data,
  calibration_half_width,
  slope_tolerance,
  r2_thres,
  plot_regression_data = FALSE,
  plot_dir = "/dev/null",
  site,
  min_nobs = NA
)

Arguments

ref_data

Reference data.frame from which to estimate calibration parameters.

calibration_half_width

Determines the period (in days) from which reference data are selected (period is 2*calibration_half_width).

slope_tolerance

Allows for filtering of slopes that deviate from 1 by slope_tolerance.

r2_thres

What is the minimum r2 value permitted in a 'useful' calibration relationship.

plot_regression_data

True or false - should we plot the data used in the regression? Useful for debugging.

plot_dir

If plot_regression_data is true, where should the plots be saved?

site

Needed for regression plots.

min_nobs

Minimum number of high-frequency observations to define a peak.

Value

Returns a data.frame of calibration parameters. Output data.frame includes slope, intercept, and r^2 values for d13C and CO2 values.


get_Rstd

Description

get_Rstd

Usage

get_Rstd(element)

Arguments

element

Which element to return standard ratio - carbon, oxygen, or hydrogen.

Value

Heavy-to-light isotope ratio of most common stable isotope standard. VSMOW for water, VPDB for carbon.

Author(s)

Rich Fiorella [email protected]

Examples

get_Rstd("carbon") # returns 0.0111797
get_Rstd("oxygen") # returns 2005.20e-6

ingest_data

Description

ingest_data

Usage

ingest_data(inname, analyte, name_fix = TRUE, amb_avg, ref_avg)

Arguments

inname

A file (or list of files) to extract data from for calibration.

analyte

Carbon (Co2) or water (H2o)?

name_fix

Fix to data frame required for next-generation calibration functions, but breaks old 'by_month()' functions. This parameter provides a necessary work around until these functions are removed.

amb_avg

The averaging interval of the ambient data to extract.

ref_avg

The averaging interval of the reference data to extract.

Value

List of data frames, taken from files specified in inname

Author(s)

Rich Fiorella [email protected]


loocv

Description

loocv

Usage

loocv(mod)

Arguments

mod

Fitted model to estimate leave-one-out CV on.

Author(s)

Rich Fiorella [email protected]

helper function for the leave-one-out cross variance


manage_local_EC_archive

Description

Utility function to help retrieve new EC data and/or prune duplicates, as NEON provisions new data or re-provisions data for an existing site and month.

Usage

manage_local_EC_archive(
  file_dir,
  get = TRUE,
  unzip_files = TRUE,
  trim = FALSE,
  dry_run = TRUE,
  sites = "all",
  release = "RELEASE-2023"
)

Arguments

file_dir

Specify the root directory where the local EC store is kept.

get

Pull down data from NEON API that does not exist locally?

unzip_files

NEON gzips the hdf5 files, should we unzip any gzipped files within file_dir? (Searches recursively)

trim

Search through local holdings, and remove older file where there are duplicates?

dry_run

List files identified as duplicates, but do not actually delete them? Default true to prevent unintended data loss.

sites

Which sites to retrieve data from? Default will be all sites with available data, but can specify a single site or a vector here.

release

Download data corresponding to a specific release? Defaults to "RELEASE-2023." To download all data, including provisional data, set to NULL.

Value

Returns nothing to the environment, but will download new NEON HDF5 files for selected sites (if get = TRUE), unzip them in the local file directory (if unzip_files = TRUE), and identify and remove suspected duplicate files (if trim = TRUE and dry_run = FALSE).

Author(s)

Rich Fiorella [email protected]


R_to_delta

Description

R_to_delta

Usage

R_to_delta(R_values, element)

Arguments

R_values

A vector of isotope ratios (e.g., R values).

element

Which element to return delta values - carbon, oxygen, or hydrogen.

Value

Vector of isotope ratios in delta notation.

Author(s)

Rich Fiorella [email protected]

Examples

R_to_delta(R_values = 2005.20e-6, element = 'oxygen') # returns 0.

restructure_carbon_variables

Description

restructure_carbon_variables

Usage

restructure_carbon_variables(dataframe, varname, mode, group)

Arguments

dataframe

Input data.frame, from neonUtilities::stackEddy

varname

Which variable are we applying this function to? There's a list of ~10 common ones to write to the hdf5 file.

mode

Are we fixing a reference data frame or an ambient data frame?

group

Data, ucrt, or qfqm?

Value

data.frame formatted for output to hdf5 file.


Wrapper function around restructure_carbon_variables and restructure_water_variables.

Description

Wrapper function around restructure_carbon_variables and restructure_water_variables.

Usage

restructure_variables(dataframe, varname, mode, group, species)

Arguments

dataframe

Input data.frame, from neonUtilities::stackEddy

varname

Which variable are we applying this function to? There's a list of ~10 common ones to write to the hdf5 file.

mode

Are we fixing a reference data frame or an ambient data frame?

group

Data, ucrt, or qfqm?

species

Set to 'Co2' for carbon; 'H2o' for water

Value

data.frame formatted for output to hdf5 file.

Author(s)

Rich Fiorella [email protected]


restructure_water_variables

Description

restructure_water_variables

Usage

restructure_water_variables(dataframe, varname, mode, group)

Arguments

dataframe

Input data.frame, from neonUtilities::stackEddy

varname

Which variable are we applying this function to? There's a list of ~10 common ones to write to the hdf5 file.

mode

Are we fixing a reference data frame or an ambient data frame?

group

Data, ucrt, or qfqm?

Value

data.frame formatted for output to hdf5 file.


select_daily_reference_data

Description

select_daily_reference_data

Usage

select_daily_reference_data(standard_df, analyte, min_nobs = NA)

Arguments

standard_df

Input reference data.frame.

analyte

Are we calibrating CO2 and H2O? (Use argument 'co2' or 'h2o', or else function will throw error)

min_nobs

Minimum number of high-frequency observations to define a peak. If not supplied, defaults are 200 for analyte = 'co2' or 30 for analyte = 'h2o'

Value

Smaller data.frame where only the reference data selected to use in the calibration routines is returned. Assumes that we are calibrating on a daily basis, and not on a longer time scale. Data are selected based on two criteria: cannot be missing, and must be at least a certain number of high-frequency observations in order to qualify as a valid measurement. For the water system, this function also keeps only the last three injections for each reference water per day.


setup_output_file

Description

Creates a skeleton hdf5 file for the calibrated data.

Usage

setup_output_file(inname, outname, site, analyte)

Arguments

inname

Input file name.

outname

Output file name.

site

NEON 4-letter site code.

analyte

Carbon ('Co2') or water ('H2o') system?

Value

Nothing to the environment, but creates a new data file with the most basic output HDF5 structure consistent with NEON's data files.

Author(s)

Rich Fiorella [email protected]


swap_standard_isotoperatios

Description

There are a few suspected instances where the water isotope ratios for oxygen and hydrogen have been flipped in the reference data. This function corrects them until they are corrected in the NEON database using a d-excess filter.

Usage

swap_standard_isotoperatios(std_frame, dxs_thres = 500)

Arguments

std_frame

Standard data frame to perform swap on.

dxs_thres

d-excess threshold to indicate when to swap.

Value

A data.frame based on std_frame, where d18O and d2H values have been swapped from NEON input files if determined to have a reference value mismatch. Mismatch is determined based on the d-excess of the standard (= d2H - 8*d18O), using a value of 500 by default.

Author(s)

Rich Fiorella [email protected]


terrestrial_core_sites

Description

terrestrial_core_sites

Usage

terrestrial_core_sites()

Value

A vector listing NEON core terrestrial sites.

Author(s)

Rich Fiorella [email protected]

Examples

terrestrial_core_sites()

terrestrial_gradient_sites

Description

terrestrial_gradient_sites

Usage

terrestrial_gradient_sites()

Value

A vector listing NEON gradient terrestrial sites.

Author(s)

Rich Fiorella [email protected]

Examples

terrestrial_gradient_sites()

validate_analyte

Description

validate_analyte

Usage

validate_analyte(analyte)

Arguments

analyte

Co2 or H2o?

Value

Standardized string for the water ('H2o') or carbon ('Co2') systems to make sure strings are standardized across package functions.

Author(s)

Rich Fiorella [email protected]


validate_output_file

Description

validate_output_file

Usage

validate_output_file(inname, outname, site, analyte)

Arguments

inname

Input file name.

outname

Output file name.

site

NEON 4-letter site code.

analyte

Carbon ('Co2') or water ('H2o') system?

Value

Nothing to environment, simply checks to make sure expected groups are in output.

Author(s)

Rich Fiorella [email protected]


water_isotope_sites

Description

water_isotope_sites

Usage

water_isotope_sites()

Value

A vector listing NEON sites measuring water vapor isotope ratios.

Author(s)

Rich Fiorella [email protected]

Examples

water_isotope_sites()

write_carbon_ambient_data

Description

Write out ambient observations from the NEON EC towers where the isotope data (either H2O or CO2) have been calibrated using this package.

Usage

write_carbon_ambient_data(outname, site, amb_data_list, to_file = TRUE)

Arguments

outname

Output file name.

site

NEON 4-letter site code.

amb_data_list

Calibrated list of ambient data - this is the output from one of the calibrate_ambient_carbon* functions.

to_file

Write to file (TRUE) or to environment (FALSE).

Value

Nothing to the environment, but writes data in amb_data_list to file.

Author(s)

Rich Fiorella [email protected]


write_carbon_calibration_data

Description

write_carbon_calibration_data

Usage

write_carbon_calibration_data(outname, site, cal_df, method, to_file = TRUE)

Arguments

outname

Output file name.

site

NEON 4-letter site code.

cal_df

Calibration data frame - this is the output from fit_carbon_regression

method

Was the Bowling et al. 2003 or the linear regression method used in fit_carbon_regression?

to_file

Write to file (TRUE) or to environment (FALSE).

Value

Nothing to the environment, but writes out the calibration parameters (e.g., gain and offset or regression slopes and intercepts) to the output hdf5 file.

Author(s)

Rich Fiorella [email protected]


write_qfqm

Description

Write NEON's qfqm data for an isotope species to output file. Wraps copy_qfqm_group.

Usage

write_qfqm(inname, outname, site, analyte)

Arguments

inname

Input file name.

outname

Output file name.

site

NEON 4-letter site code.

analyte

Carbon ('Co2') or water ('H2o') system?

Value

Nothing to the environment, but writes qfqm data to file.

Author(s)

Rich Fiorella [email protected]


write_ucrt

Description

Write NEON's ucrt data for an isotope species to output file. Wraps copy_ucrt_group.

Usage

write_ucrt(inname, outname, site, analyte)

Arguments

inname

Input file name.

outname

Output file name.

site

NEON 4-letter site code.

analyte

Carbon ('Co2') or water ('H2o') system?

Value

Nothing to the environment, but writes ucrt data to file.

Author(s)

Rich Fiorella [email protected]


write_water_ambient_data

Description

Write out ambient observations from the NEON EC towers where the isotope data have been calibrated using this package.

Usage

write_water_ambient_data(outname, site, amb_data_list)

Arguments

outname

Output file name.

site

NEON 4-letter site code.

amb_data_list

Calibrated list of ambient data - this is the output from one of the calibrate_ambient_water* functions.

Value

Nothing to the environment, but writes data in amb_data_list to file.

Author(s)

Rich Fiorella [email protected]


write_water_calibration_data

Description

write_water_calibration_data

Usage

write_water_calibration_data(outname, site, cal_df)

Arguments

outname

Output file name.

site

NEON 4-letter site code.

cal_df

Calibration data frame - this is the output from fit_water_regression

Value

Nothing to the environment, but writes out the calibration parameters (e.g., regression slopes and intercepts) to the output hdf5 file.

Author(s)

Rich Fiorella [email protected]