An average of 393.69ppm CO2 concentration was measured at Scripps’ Mauna Loa, Hawai’i’s Observatory during June 2011. In the past, I reported on the NOAA observation, but it either hasn’t been updated recently or separate measurements have been combined somehow. This post, like last month’s, will compare Scripps data against Scripps data – not Scripps versus NOAA.
That value is the highest value for June in recorded history. Last year’s 392.03 was the previous highest June value ever recorded, which mean that this June’s value 1.63ppm higher than June 2010.
The yearly maximum monthly value normally occurs during May. This year was no different: the 394.16 concentration is the highest value reported both this year and all time.
This will likely be the last year that CO2 concentrations will fall below 390ppm during any calendar month. Although it hasn’t happened yet (every month in 2011 has recorded at least 390ppm), the yearly minimum that normally occurs in September is upcoming. Given the trend from May to September in years past, 2011’s minimum should be ~388ppm.
Our species’ aggressive march toward 400ppm and beyond continues. Keep in mind that scientists have recommended that 350ppm should be the target for which humanity should aim in order to keep climate extremes from overwhelming our civilization and the globe’s ecosystems.