On The Relationship Between Atmospheric Carbon Dioxide And Global Temperature

Abstract

The study of dynamic relationships between the atmospheric carbon dioxide and the Earth’s global temperature in the current changing climate supported the notion that the trend in the global temperature followed the trend in the atmospheric CO2 before the climate hiatus that started in the beginning of the 21st century. During the hiatus period, the heat trapped by the atmospheric CO2 is going mostly to the ocean. This conclusion is supported by comparison of the CO2 trend with the trend in the ocean heat content. The phase relationships between the CO2 and temperature are more complicated after the removal of the trends. The phase relationships are chaotic on time scales shorter than the annual time scale. During 1986-2008, the atmospheric CO2 changed in anti- phase with the global temperature. The phase relationship reversed in 1979 and after 2010. The atmospheric CO2 was in-phase with the global temperature on the El Niño time scale (2.3 - 7 years) except during very strong El Niño years in 1991-1999 when CO2 led the global temperature.