---
title: "Introduction to TCHazaRds"
author: "Julian O'Grady"
output: rmarkdown::html_vignette
date: "`r Sys.Date()`"
vignette: >
  %\VignetteIndexEntry{Introduction_to_TCHazaRds}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---

```{r setup, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)
```

R's compatibility to easily use fast `Cpp` code ([Rcpp](https://github.com/RcppCore/Rcpp)) and spatial processing (e.g. [terra](https://github.com/rspatial/terra)) makes it an attractive open source environment to study tropical cyclones, also known as TCs, hurricanes and typhoons. This package estimates TC vortex wind and pressure fields using parametric equations originally coded up in python by [TCRM](https://github.com/GeoscienceAustralia/tcrm) and in Cuda Cpp by [TCwindgen](https://github.com/CyprienBosserelle/TCwindgen).

TC wind fields can be computed using three model inputs of the: 1) [TC Track](#input1), 2) [Model Parameters](#input2) and 3) [Model Spatial Domain](#input3). The TCHazaRds package can be used with other visualization and spatial analysis packages to analyse the impacts of TCs.

```{r}
suppressPackageStartupMessages(require(TCHazaRds))   # this package :)
suppressPackageStartupMessages(require(terra))       # spatial analysis
suppressPackageStartupMessages(require(rasterVis))   # enhanced raster visualization https://oscarperpinan.github.io/rastervis/
suppressPackageStartupMessages(require(sp))          # spatial methods and plotting
suppressPackageStartupMessages(require(knitr))       # formatted table
suppressPackageStartupMessages(require(raster))       # convert for raster plots

```

<a name="input1"></a>

## Input 1: The TC Track  

The first thing that is required to model near- and far-field TC winds is the TC track/path. The functions in TCHazaRds require that the tracks have a "shape-file" like spatial-vector format and have attributes of pressure, date/time, location and forward speed and direction. 

```{r}
TCi = vect(cbind(c(154,154),c(-26.1,-26)),"lines",crs="epsg:4283") #track line segment
TCi$PRES = 950 #central pressure in hPa
#TCi$RMW = 40 #radius of maximum winds in km
TCi$ISO_TIME = "2022-10-04 20:00:00" #"%Y-%m-%d %H:%M:%S", tz = "UTC"
TCi$LON = geom(TCi)[1,3] #longitude
TCi$LAT = geom(TCi)[1,4] #latitude
TCi$STORM_SPD = perim(TCi)/(3*3600) #speed of the forward motion of the TC m/s
TCi$thetaFm = 90-returnBearing(TCi) #direction of the heading of the TC (Cartesian, clockwise from x axis)

```

In the above code chunk a simple track segment is defined, but historical TC tracks, e.g. from Best Track Archive for Climate Stewardship (IBTrACS), can provide the input into the model. A few tracks are provided with the package, below TC Yasi is read in.

```{r}
TC <- vect(system.file("extdata/YASI/YASI.shp", package="TCHazaRds"))
TC$PRES <- TC$BOM_PRES #different agencies each provide a PRES, you need to chose one. 
TC$STORM_SPD = TC$STORM_SPD/1.94 #provided as knots, convert to m/s
TC$thetaFm = 90-returnBearing(TC) #direction of the heading of the TC (Cartesian, clockwise from x axis)
TCi = TC[46]
```

<a name="input2"></a>

## Input 2: The TC model parameters  

The second thing required to run the model is a list of parameters, which are provided for the default settings with the package and shown below.

```{r}
paramsTable = read.csv(system.file("extdata/tuningParams/defult_params.csv",package = "TCHazaRds"))
knitr::kable(paramsTable,caption = "Parameter file")
```
<a name="Input3"></a>

## Input 3: The TC model spatial domain  

finally, the domain and geometry for the model output needs to be defined. The domain size and coordinates are calculated with the `land_geometry` function. A domain can simply be defined with `terra::rast`. Further to this a coastline polygon can be `rasterize`'d to define land, and the inland distance can be calculated with the `terra::costDistance` function to reduce winds overland due to terrestrial roughness (under development and commented out for now). 

```{r, out.width = '80%',fig.height=4,fig.width=6, fig.align = "center"}
r = rast(xmin = 145,xmax=149,ymin = -19,ymax = -16.5,resolution=.01)
values(r) = 0
#GEO_land = land_geometry(r,r)

#
land_v <- vect(system.file("extdata/OSM_500m_QLD/OSM_500m_QLD.shp", package="TCHazaRds"))
land_r = rasterize(land_v,r,touches=TRUE,background=0)
inland_proximity = terra::costDist(land_r,target = 0,scale=1)
GEO_land = land_geometry(land_r,inland_proximity)

#plot(inland_proximity,main = "Inland Distance (m)")
#plot(TC,add=TRUE)

```

## Output Wind and Wave Field 
Now that we have the three inputs (tracks, parameters and model output geometry) we can compute and plot the spatial wind hazard. See [Making maps in R](https://r.geocompx.org/adv-map.html) for plotting method. Ocean Wave parameters can be returned with `returnWaves = TRUE`

```{r, out.width = '80%',fig.height=4,fig.width=6, fig.align = "center"}
ats = seq(0, 65, length=14)
HAZi = TCHazaRdsWindField(GEO_land = GEO_land,TC = TCi,paramsTable=paramsTable,returnWaves = TRUE)
library(raster)       # convert for raster plots
dummy = raster::raster() 
TC_sp = list("sp.lines",as(TC,"Spatial"),col="black")
sp::spplot(HAZi,"Sw",at=ats,sp.layout = TC_sp,main = "Surface wind speed [m/s]")
ats = seq(0, 16, length=9)
sp::spplot(HAZi,"Hs0",at=ats,sp.layout = TC_sp,main = "Deep water significant wave height [m]")

```

The package `rasterVis::` allows pretty spatial vector plots of the wind field via the `vectorplot` function (tested on MS-Windows machine).

```{r, out.width = '80%',fig.height=4,fig.width=6, fig.align = "center"}
ats = seq(0, 65, length=14)
if (.Platform$OS.type == "windows"){
  UV = as(c(HAZi["Uw"],HAZi["Vw"]),"Raster") #need to convert back to raster
  rasterVis::vectorplot(UV, isField='dXY', col.arrows='white', aspX=0.002,aspY=0.002,at=ats ,
  colorkey=list(at=ats), par.settings=viridisTheme)+latticeExtra::layer(sp.lines(as(TC,"Spatial"),col="red"))
}
```

The hazard can be also calculated for the entire track too (by adding a `s` to the end of `TCHazaRdsWindField` to make it plural), and then the maximum wind speed at each grid cell can be plotted.

```{r, out.width = '80%',fig.height=4,fig.width=6, fig.align = "center"}
TC = crop(TC,as.polygons(ext(GEO_land)))
HAZ = TCHazaRdsWindFields(GEO_land=GEO_land,TC=TC,paramsTable=paramsTable,returnWaves = TRUE)
sp::spplot(max(HAZ$Sw),at=ats,sp.layout = TC_sp)
```

The track can be interpolate to say, hourly intervals by defining an `outdate` from the start to the end date of the TC, stepping by 3600 seconds.
The output from these functions can be written to a netcdf file for input to force hydrodynamic or wave modelling by including `outfile` filename in the function call (not shown here, see `?TCHazaRdsWindFields`). 

```{r, out.width = '80%',fig.height=4,fig.width=6, fig.align = "center"}
outdate = seq(strptime(TC$ISO_TIME[1],"%Y-%m-%d %H:%M:%S",tz="UTC"),
              strptime(rev(TC$ISO_TIME)[1],"%Y-%m-%d %H:%M:%S",tz="UTC"),
              3600)
HAZI = TCHazaRdsWindFields(outdate=outdate,GEO_land=GEO_land,TC=TC,paramsTable=paramsTable)
sp::spplot(max(HAZI$Sw),at=ats,sp.layout = TC_sp)
```

## Output wind time series  


Time series data can be computed for a single location. Below is a comparison of the raw IBTrACS time step and the track interpolated to 10 minute intervals.(tested on MS-Windows machine) 

```{r, out.width = '80%',fig.height=4,fig.width=6, fig.align = "center"}

outdate = seq(strptime(TC$ISO_TIME[1],"%Y-%m-%d %H:%M:%S",tz="UTC"),
              strptime(rev(TC$ISO_TIME)[1],"%Y-%m-%d %H:%M:%S",tz="UTC"),
              600)

GEO_landp = data.frame(dem=0,lons = 147,lats=-18,f=-4e-4,inlandD = 0)
HAZts = TCHazaRdsWindTimeSereies(GEO_land=GEO_landp,TC=TC,paramsTable = paramsTable)
HAZtsi = TCHazaRdsWindTimeSereies(outdate = outdate,GEO_land=GEO_landp,TC=TC,paramsTable = paramsTable)

main =  paste(TCi$NAME[1],TCi$SEASON[1],"at",GEO_landp$lons,GEO_landp$lats)
if (.Platform$OS.type == "windows"){ 
  suppressWarnings(with(HAZts,plot(date,Sw,format = "%b-%d %HZ",type="l",main = main,ylab = "Wind speed [m/s]")))
  with(HAZtsi,lines(date,Sw,col=2))
  legend("topleft",c("6 hrly","10 min interpolated"),col = c(1,2),lty=1)
}
```

## Output wind Profile 

Wind profiles can be calculated for a single time step. Here we estimate the wind speed values along the profile that is 90 degrees clockwise (at right angles) from the TC heading/bearing direction.

```{r, out.width = '80%',fig.height=4,fig.width=6, fig.align = "center"}
TCi$thetaFm = 90-returnBearing(TCi)
pp <- TCProfilePts(TC_line = TCi,bear=TCi$thetaFm+90,length =150,step=1)
#extract the GEO_land
GEO_land_v = extract(GEO_land,pp,bind=TRUE,method = "bilinear")
HAZp = TCHazaRdsWindProfile(GEO_land_v,TCi,paramsTable)

HAZie = extract(HAZi,pp,bind=TRUE)#,method = "bilinear")

wcol = colorRampPalette(c("white","lightblue","blue","violet","purple"))
#see ?terra::plot
plot(HAZi,"Sw",levels=ats,col = wcol(13),range = range(ats),type="continuous",all_levels=TRUE)
#plot(HAZp,add=TRUE,cex=1.2)
plot(HAZp,"Sw",levels=ats,col = wcol(13),range = range(ats),type="continuous",border="grey")#,all_levels=TRUE)
lines(TC)
```

TC wind fields can be modelled, or tested, with observed, or constant, B (Beta) profile peakedness parameter by defining TC$B and setting `betaModel = NA` in paramsTable
```{r}
TCi$B = 2.2
paramsTableCB = paramsTable
paramsTableCB$value[paramsTableCB$param == "betaModel"] = NA
HAZpCP = TCHazaRdsWindProfile(GEO_land_v,TCi,paramsTableCB)

```

Other parameters can be adjusted, here we model a larger outer radius (RMAX2) profile parameter by defining TC$RMAX2 and setting rMax2Model = NA in paramsTable
```{r}
TCi$RMAX2 = 200
paramsTableRMAX2 = paramsTable
paramsTableRMAX2$value[paramsTableRMAX2$param == "rMax2Model"] = NA
HAZpRMAX2 = TCHazaRdsWindProfile(GEO_land_v,TCi,paramsTableRMAX2)

```


Positive radial distance values are to the right of the forward motion (90 deg clockwise).

```{r, out.width = '80%',fig.height=4,fig.width=6, fig.align = "center"}
plot(HAZp$radialdist,HAZp$Sw,type="l",xlab = "Radial distance [km]",ylab = "Wind speed [m/s]",ylim = c(0,70));grid()
lines(HAZp$radialdist,HAZpCP$Sw,col=2)
lines(HAZpRMAX2$radialdist,HAZpRMAX2$Sw,col=4)
legend("topleft",c("B = MK14, RMAX2 = 150 km",paste0("B = ",TCi$B,", RMAX2 = 150 km"),paste0("B = MK14, RMAX2 = ",TCi$RMAX2," km")),lty=1,col = c(1,2,4),cex=.7)
title("Profiles of different peakness B and outer radius RMAX2 parameters",cex.main=.9)

```


Julian O'Grady is a @csiro.au climate scientist investigating coastal hazards and impacts.

