R/depth2pressure.R

In tagtools: Work with Data from High-Resolution Biologging Tags

#' Convert depth to pressure
#' 
#' This function is used to convert the depth (in meters) to the pressure in Pascals.
#' @param d The depth in meters
#' @param latitude The latitude in degrees
#' @return The pressure in Pa
#' @note Based on the Leroy and Parthiot (1998) formula. See: http://resource.npl.co.uk/acoustics/techguides/soundseawater/content.html#UNESCO
#' @export
#' @examples depth2pressure(1000, 27)

depth2pressure <- function(d, latitude) {
  if (missing(latitude)) {
    stop("inputs for all arguments are required")
  }
  thyh0Z <- 1e-2 * d / (d + 100) + 6.2e-6 * d
  g <- 9.7803 * (1 + 5.3e-3 * sin(latitude * pi / 180)^2)
  k <- (g - 2e-5 * d) / (9.80612 - 2e-5 * d)
  hZ45 <- 1.00818e-2 * d + 2.465e-8 * d^2 - 1.25e-13 * d^3 + 2.8e-19 * d^4
  p <- 1e6 * (hZ45 * k - thyh0Z)
  return(p)
}