Calculate AD loads and summarize

Usage

anlz_ad(
  ad_rain,
  vernafl,
  summ = c("segment", "all"),
  summtime = c("month", "year")
)

Arguments

ad_rain: data frame of daily rainfall data from NOAA NCDC, obtained using util_ad_getrain
vernafl: character vector of file path to Verna Wellfield atmospheric concentration data
summ: chr string indicating how the returned data are summarized, see details
summtime: chr string indicating how the returned data are summarized temporally (month or year), see details

Value

A data frame with nitrogen and phosphorus loads in tons/month, hydrologic load in million m3/month, and segment, year, and month as columns if summ = 'segment' and summtime = 'month'. Total load to all segments can be returned if summ = 'all' and annual summaries can be returned if summtime = 'year'. In the former case, the total excludes the northern portion of Boca Ciega Bay that is not included in the reasonable assurance boundaries. In the latter case, loads are the sum of monthly estimates such that output is tons/yr for TN and TP and as million m3/yr for hydrologic load.

Details

Loading from atmospheric deposition (AD) for bay segments in the Tampa Bay watershed are calculated using rainfall data and atmospheric concentration data from the Verna Wellfield site. Rainfall data must be obtained using the util_ad_getrain function before calculating loads. For convenience, daily rainfall data from 2017 to 2023 at sites in the watershed are included with the package in the ad_rain object. The Verna Wellfield data must also be obtained from https://nadp.slh.wisc.edu/sites/ntn-FL41/ as monthly observations. This file is also included with the package and can be found using system.file as in the examples below. Internally, the Verna data are converted to total nitrogen and total phosphorus from ammonium and nitrate concentration data (see util_ad_prepverna for additional information).

The function first estimates the total hydrologic load for each bay segment using daily estimates of rainfall at NWIS NCDC sites in the watershed. This is done as a weighted mean of rainfall at the measured sites relative to grid locations in each sub-watershed for the bay segments. The weights are based on distance of the grid cells from the closest site as inverse distance squared. Total hydrologic load for a bay segment is then estimated by converting inches/month to m3/month using the segment area. The distance data and bay segment areas are contained in the ad_distance file included with the package.

The total nitrogen and phosphorus loads are then estimated for each bay segment by multiplying the total hydrologic load by the total nitrogen and phosphorus concentrations in the Verna data. The loading calculations also include a wet/dry deposition conversion factor to account for differences in loading during the rainy and dry seasons.

Examples

vernafl <- system.file('extdata/verna-raw.csv', package = 'tbeploads')
data(ad_rain)
anlz_ad(ad_rain, vernafl)
#> # A tibble: 672 × 7
#>     Year Month source segment        tn_load tp_load hy_load
#>    <int> <dbl> <chr>  <chr>            <dbl>   <dbl>   <dbl>
#>  1  2017     1 AD     Boca Ciega Bay   1.13   0.0192    1.98
#>  2  2017     2 AD     Boca Ciega Bay   0.945  0.0168    1.95
#>  3  2017     3 AD     Boca Ciega Bay   0.950  0.0181    2.48
#>  4  2017     4 AD     Boca Ciega Bay   3.23   0.0504    3.90
#>  5  2017     5 AD     Boca Ciega Bay   9.06   0.131     6.89
#>  6  2017     6 AD     Boca Ciega Bay   9.67   0.178    22.5 
#>  7  2017     7 AD     Boca Ciega Bay  10.8    0.189    26.2 
#>  8  2017     8 AD     Boca Ciega Bay   5.58   0.120    24.6 
#>  9  2017     9 AD     Boca Ciega Bay   2.14   0.0553   14.1 
#> 10  2017    10 AD     Boca Ciega Bay   0.493  0.0174    5.56
#> # ℹ 662 more rows