index_Fosberg: Fosberg Fire Weather Index.

In ozjimbob/ecbtools: Environmental Change Biology Tools

Usage

index_Fosberg(Temp, Wind, Dew)

Arguments

Temp
Wind
Dew

Examples

##---- Should be DIRECTLY executable !! ----
##-- ==>  Define data, use random,
##--	or do  help(data=index)  for the standard data sets.

## The function is currently defined as
function (Temp, Wind, Dew) 
{
    humid <- calc_humid(Temp, Dew)
    Wind <- Wind/1.6
    Temp = Temp * (9/5) + 32
    FFI_list <- c()
    llength <- length(Temp)
    for (day in 1:llength) {
        if (is.na(humid[day])) {
            FFI_list <- append(FFI_list, NA)
        }
        else {
            if (humid[day] < 10) {
                m = 0.03229 + 0.281073 * humid[day] - 0.000578 * 
                  humid[day] * Temp[day]
            }
            if (humid[day] >= 10 & humid[day] <= 50) {
                m = 2.22749 + 0.160107 * humid[day] - 0.01478 * 
                  Temp[day]
            }
            if (humid[day] > 50) {
                m = 21.0606 + 0.005565 * humid[day]^2 - 0.00035 * 
                  humid[day] * Temp[day] - 0.483199 * humid[day]
            }
            n = 1 - 2 * (m/30) + 1.5 * (m/30)^2 - 0.5 * (m/30)^3
            FFWI = n * ((1 + Wind[day]^2)^0.5)/0.3002
            FFI_list <- append(FFI_list, FFWI)
        }
    }
    FFI_list
  }

ozjimbob/ecbtools documentation built on Jan. 18, 2021, 7:39 p.m.