Happy #421ppm, everyone! I increased the vertical axis range by 10ppm (the second time since first publishing this chart in 2017!). And I'll likely will have to do it again around 2026 😞 https://t.co/8XENkoIkJA

Happy #421ppm, everyone! I increased the vertical axis range by 10ppm (the second time since first publishing this chart in 2017!). And I'll likely will have to do it again around 2026 😞 https://t.co/8XENkoIkJA
