It's due to vegetation growth during the summer in the northern hemisphere https://www.climate.gov/news-features/understanding-climate/climate-change-atmospher

It's due to vegetation growth during the summer in the northern hemisphere https://www.climate.gov/news-features/understanding-climate/climate-change-atmospheric-carbon-dioxide#:~:text=The%20seasonal%20cycle%20of%20highs,is%20driven%20by%20human%20activities https://www.climate.gov/news-features/understanding-climate/....