Weekly average CO2 at Mauna Loa observatory, Hawaii
Measurements taken by the National Oceanic and Atmospheric Administration
Week beginning on Aug. 16, 2015: 399.13 parts per million
Weekly value from one year ago: 396.81 ppm
Weekly value from 10 years ago: 378.79 ppm
Global data:
400.11 ppm for June 2015
397.52 ppm for June 2014
