Atmospheric CO2 Data For June, 2016, Posted -- July 6, 2016

Down a bit from last month, 407.70 in May:

Atmospheric CO2 is tracked here, CO2 Now.

Atmospheric CO2 varies seasonally, so one cannot necessarily compare month-after-month. It is best to compare year-over-year. Atmospheric CO2 tends to peak in the spring (May) and then fall steadily through the summer, reaching its low point for the year around September, at which time it starts to rise again, rising during the winter months (northern hemisphere) and peaking around May, where the cycle starts all over again.

One can follow daily atmospheric CO2 readings here. For example, the most recent data available is from July 4, 2016, just a couple of days ago, an the reading was 405.70. The monthly average for July, 2015, last year, was about 402; for June, last year, about 403.