Hitzetage in Wien und den Bundesländern mit ZAMG API (https://twitter.com/matschnetzer/status/1599781018575044608)

hitzetage.R

library(tidyverse)
library(lubridate)
library(httr)
library(jsonlite)
library(msthemes)
library(geojsonsf)
library(sf)

# Get data: https://dataset.api.hub.zamg.ac.at/app/station-new/historical/klima-v1-1d?anonymous=true or use API like here

stations <- tribble(
  ~id, ~name,
  105, "Wien",
  131, "Salzburg",
  93, "Niederösterreich",
  56, "Oberösterreich",
  48, "Kärnten",
  39, "Tirol",
  30, "Steiermark",
  22, "Burgenland",
  15, "Vorarlberg"
)

res.api = GET(glue::glue("https://dataset.api.hub.zamg.ac.at/v1/station/historical/klima-v1-1d?parameters=tmax&start=1950-01-01&end=2022-12-01&station_ids=",paste0(stations$id,collapse = ",")))

data <- fromJSON(rawToChar(res.api$content))
tempdat <- tribble(~time, ~id, ~tmax)

for (i in 1:nrow(stations)) {
  add.dat <- data.frame(time = as.Date(data[["timestamps"]]),
                        id = as.numeric(data[["features"]][["properties"]][["station"]][[i]]),
                        tmax = data[["features"]][["properties"]][["parameters"]][["tmax"]][["data"]][[i]])
  tempdat <- bind_rows(tempdat, add.dat)
}

blmap <- geojson_sf("https://raw.githubusercontent.com/ginseng666/GeoJSON-TopoJSON-Austria/master/2021/simplified-95/laender_95_geo.json")

findat <- tempdat |> left_join(stations) |> 
  mutate(time = ymd(time)) |> 
  group_by(year(time), name, .drop = FALSE) |>  
  filter(tmax >= 30) |>  count() |> 
  rename(year = `year(time)`) 

plotdat <- blmap |> left_join(findat)

plotdat |> ggplot(aes(fill = n)) +
  facet_wrap(~year, ncol = 10) +
  geom_sf(linewidth = 0.05, color = "black") +
  scale_fill_gradient(low = "white", high = "red", name = "Anzahl Hitzetage") +
  guides(fill = guide_colorbar(direction = "horizontal", barheight = 0.5, 
                               barwidth = 10, title.position = "top")) +
  labs(title = "Hitzetage in Österreich",
       subtitle = "Anzahl der Tage mit 30°C oder wärmer nach Bundesland",
       caption = "Anm.: Messdaten der jeweiligen Landeshauptstadt\nQuelle: ZAMG. Grafik: @matschnetzer") +
  theme_ms(grid = F, alttf = T) +
  theme(axis.text = element_blank(),
        strip.text = element_text(size = 7, family = "Raleway"),
        legend.position = "none")

ggsave("hitzetage.png", width = 8, height = 5, dpi = 320) 


# Vienna only
wien <- blmap |> filter(name == "Wien")
wiendat <- findat |> filter(name == "Wien")

wienplot <- wien |> left_join(wiendat)

wienplot |> ggplot(aes(fill = n)) +
  facet_wrap(~year, ncol = 10) +
  geom_sf(linewidth = 0.05, color = "black") +
  geom_text(aes(x=16.37505, y= 48.20915, label = n), size = 5, family = "Hack",
            fontface = "bold", color = "white", alpha = 0.8) +
  scale_fill_gradient(low = "grey90", high = "red", name = "Anzahl Hitzetage") +
  guides(fill = guide_colorbar(direction = "horizontal", barheight = 0.5, 
                               barwidth = 10, title.position = "top")) +
  labs(title = "Hitzetage in Wien",
       x=NULL, y=NULL,
       subtitle = "Anzahl der Tage mit 30°C oder wärmer",
       caption = "Daten: ZAMG. Grafik: @matschnetzer") +
  theme_ms(grid = F, alttf = T) +
  theme(axis.text = element_blank(),
        strip.text = element_text(size = 7, family = "Raleway"),
        legend.position = "none")

ggsave("hitzetagewien.png", width = 7, height = 6, dpi = 320)