droughts.Rmd

---
title: "droughts"
author: "Gracie Goheen"
date: "`r Sys.Date()`"
output: 
  github_document:
    toc: true
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```

```{r message=FALSE, warning=FALSE}
# Libraries
library(tidyverse)
library(sf)

# Parameters
  # Rainfall .grid file for December 2019
rainfall_dec19_raw <- "/Users/graciegoheen/Downloads/dcl/own/rainfall/2019120120191231.grid"
  # Geometry data for countries
countries_data <- "/Users/graciegoheen/Downloads/dcl/ne_110m_admin_0_countries/ne_110m_admin_0_countries.shp"
#===============================================================================


countries <- read_sf(dsn = countries_data)
australia <- 
  countries %>% 
  filter(NAME == "Australia")

```

## Clean the data

```{r}
rainfall_dec19_matrix <- 
  rainfall_dec19_raw %>% 
  read_delim(
    delim = " ", 
    col_names = FALSE, 
    na = "99999.90", 
    trim_ws = TRUE, 
    skip = 6, 
    n_max = 691) %>% 
  select(-X887) %>% 
  as.matrix()
```

```{r}
rainfall_dec19 <-
  crossing(i = 1:691, j = 1:886) %>% 
  mutate(
    rainfall = map2_dbl(i, j, ~ rainfall_dec19_matrix[.x,.y]),
    lat = -44.500 + 0.050 * 691 - 0.050 * i,
    long = 112.000 + 0.050 * j
  ) %>%
  select(long, lat, rainfall)
```

```{r}
# rainfall_dec19_aus <-
#   st_intersection(
#     x = rainfall_dec19 %>% st_as_sf(coords = c("long", "lat"), crs = 4326) ,
#     y = australia
#   )
```


## Plot

```{r}
# rainfall_dec19_aus %>% 
#   transmute(
#     rainfall,
#     long = st_coordinates(geometry) %>% as_tibble() %>% pull(X),
#     lat = st_coordinates(geometry) %>% as_tibble() %>% pull(Y)
#   ) %>% 
#   ggplot() +
#   geom_tile(aes(x = long, y = lat, fill = rainfall)) +
#   geom_sf(data = australia, size = 0.1, fill = NA) +
#   scale_fill_gradientn(colors = heat.colors(9, rev = TRUE)) +
#   theme_void()
```