![]() |
Human activity behind nearly all warming: Study |
Virtually all global warming since the industrial era has been caused by manmade emissions, according to research published on Monday. Near-surface air temperatures have increased on average around the world just over one degree Celsius since the mid-19th century. That 1one degree Celsius increase has already caused more frequent and powerful extreme weather events such as droughts and floods as well as super-storms made more deadly by rising seas. The 2015 Paris climate accord commits nations to limit global temperature rises to 'well below' 2 degree Celsius and to a safer cap of 1.5 degree Celsius, if possible. An international team of researchers wanted to better quantify how much warming can be directly contributed to human activity - in the form of greenhouse gas emissions and land use change - and how much is down to so-called 'natural forcing'. These include phenomena such as large volcanic eruptions and changes in the Sun's energy output, and are often cited as drivers of warming by climate sceptics or deniers. The researchers examined 13 different climate models to simulate expected temperature changes under three main scenarios: one in which just aerosol affected temperature, one where only natural forcings occurred, and another where greenhouse gas emissions are factored in. Human activities had contributed 0.9-1.3C to global temperatures - exactly consistent with the 1.1C of warming observable on Wednesday. |