Half of anthropogenic warming now caused by fossil fuels

Using recent emissions data and a climate emulator, the 2020s are identified as the decade during which fossil-fuel combustion likely becomes the dominant driver of global warming. Prior to 2020, other activities – including agricultural, forestry, and other land use – were likely the major contributors to warming. Before 1980, the net effect of fossil fuels was likely cooling, as their generation of sulfate aerosols dominated over the cumulative effect of their greenhouse gases. In recent decades, the accumulation of long-lived carbon dioxide in the atmosphere, alongside a decrease in sulfate emissions, has resulted in a substantial increase in the warming attributable to fossil fuels. This has led to fossil fuels and other activities contributing about equally to anthropogenic warming at present. On the other hand, fossil fuels are responsible for the vast majority of committed warming.