Climate scientists are sounding the alarm on global warming. According to a recent analysis, it is now "impossible" to keep long-term warming under two degrees Celsius, which was the fallback target of the Paris climate accord. The study, published in the journal Environment Science and Policy for Sustainable Development, was led by renowned climatologist James Hansen. It concluded that Earth's climate is more sensitive to rising greenhouse gas emissions than previously thought. Compounding the crisis, according to the scientists, is a recent decline in sunlight-blocking aerosol pollution from the shipping industry. This had been mitigating some of the warming. An ambitious climate change scenario outlined by the UN's climate panel gave the planet a 50 percent chance of keeping warming under 2C by the year 2100. However, Hansen and his colleagues argue that this scenario is now "impossible." " That scenario is now impossible ," said Hansen, formerly a top NASA climate scientist who famously announced to the US Congress in 1988 that global warming was underway. Instead, he and co-authors argued, the amount of greenhouse gases already pumped into the atmosphere by burning fossil fuels meant increased warming is now guaranteed.

Climate scientists are sounding the alarm on global warming. According to a recent analysis, it is now "impossible" to keep long-term warming under two degrees Celsius, which was the fallback target of the Paris climate accord. The study, published in the journal Environment Science and Policy for Sustainable Development, was led by renowned climatologist James Hansen. It concluded that Earth's climate is more sensitive to rising greenhouse gas emissions than previously thought. Compounding the crisis, according to the scientists, is a recent decline in sunlight-blocking aerosol pollution from the shipping industry. This had been mitigating some of the warming. An ambitious climate change scenario outlined by the UN's climate panel gave the planet a 50 percent chance of keeping warming under 2C by the year 2100. However, Hansen and his colleagues argue that this scenario is now "impossible." " That scenario is now impossible ," said Hansen, formerly a top NASA climate scientist who famously announced to the US Congress in 1988 that global warming was underway. Instead, he and co-authors argued, the amount of greenhouse gases already pumped into the atmosphere by burning fossil fuels meant increased warming is now guaranteed.