Climate spiral for Austria (https://twitter.com/matschnetzer/status/1507062559106637831?s=20&t=_EiODPN1J8Mlv5ZEh0f37g)

climate_spiral.R

library(tidyverse)
library(lubridate)
library(msthemes)
library(gganimate)

# Get data from https://zamg.ac.at/histalp/dataset/station/csv.php
raw <- read_csv2("HISTALP_AT_WIE_T01_1760_2025.csv", skip = 13)

temp <- raw %>% select(year:dec) %>%
  pivot_longer(names_to = "month", values_to = "value", cols = jan:dec) %>%
  filter(year %in% 1900:2021)

findf <- temp %>%
  with_groups(month, mutate, abw = value*0.1 - mean(value*0.1)) %>%
  with_groups(year, mutate, abw_yr = mean(value*0.1) - mean(temp$value*0.1)) %>%
  mutate(date = dmy(paste("01",month,year)),
         reveal_time = rep(1:(n()/4), each = 4))

output <- findf %>%
  ggplot(aes(x = month(date, label=T), y = abw, color = abw_yr, group = year)) +
  geom_line(size = 0.6) +
  geom_hline(yintercept = 0, color = "white") +
  geom_hline(yintercept = c(-4,4), color = c("skyblue3","red1"), size = 0.2) +
  geom_vline(xintercept = 1:12, color = "white", size = 0.2) +
  annotate("label", x = 12.5, y = seq(-4,4,4), label = c("-4°C","0°C","+4°C"), 
           color = c("skyblue3","white","red1"), size = 2.5, fill = "#464950", 
           label.size = NA, label.padding = unit(0.1, "lines"),) +
  geom_point(x = 1, y = -11, size = 15, color = "#464950") + 
  geom_label(aes(x = 1, y = -11, label = year), 
             color = "white", size = 4, 
             fill = "#464950", label.size = NA) +
  coord_polar(start = 0) +
  scale_y_continuous(breaks = seq(-4,4,4)) +
  scale_color_gradientn(colors = rev(RColorBrewer::brewer.pal(n=11, name = "RdBu")),
                        limits = range(findf$abw_yr)) +
  labs(x = "", y = "",
       title = "Klima-Spirale in Österreich",
       subtitle = "Abweichung der Temperatur vom Durchschnitt 1900-2021 in Wien",
       caption = "Idee: Ed Hawkins. Grafik: @matschnetzer") + 
  theme_ms(dark = T, grid = F, alttf = T) +
  theme(axis.text.x = element_text(margin = margin(t = -20, unit = "pt")),
        axis.text.y = element_blank(),
        plot.subtitle = element_text(size = 9),
        legend.position = "none")

anim <- output +
  transition_manual(reveal_time, cumulative = T) +
  ease_aes('linear')

gifout <- animate(anim, end_pause = 30, nframes = 366,
                  height = 5, width = 5, units = "in", res = 300)

anim_save("climatespiral.gif", gifout)