To sum up, anthropogenic sulfur emissions appear to be the main cause of the mid-century cooling. These emissions decreased the mean global surface temperature by approximately 0.5°C during this period, while anthropogenic greenhouse gas emissions caused a warming of approximately 0.4°C. Therefore, even though greenhouse gas emissions continued to have a warming effect during this period, it was more than offset (hidden) by anthropogenic aerosol emissions, until those emissions were brought under control by government intervention while greenhouse gas emissions continued to increase unabated.
