Global warming continued apace. The ozone hole was unusually small.
Atmospheric CO2 continued to increase rapidly by 2.5 ppm, 14% slower than the previous year but 12% faster than the average 2000–2018 rate. Average CO2 concentration reached 411 ppm; a 30% increase from 1960.
Global air temperatures continued to be high: 2019 was 0.81°C above the 1961-1990 mean and the second highest in the historical record.
The ozone hole shrunk. Maximum extent was 58% smaller than the previous year due to an unusual polar air circulation pattern.
Sea ice extent continued to decline. Ice extent on both hemispheres was the lowest since 1978. Their combined extent was 7% lower than the 2000–2018 average.
source: Australia’s Environment in 2019 Summary Report (link)