Turn Down the Heat 3

The latest report in the series from the World Bank indicates that the world is already "locked in" to 1.5 degrees Celsius of warming above the pre-industrial level by mid-century.  There's a 40 percent chance of exceeding 4 degrees of warming by 2100.

Current warming is at 0.8°C above pre-industrial levels. CO2 emissions are now 60 percent higher than in 1990, growing at about 2.5 percent per year. If emissions
continue at this rate, atmospheric CO2 concentrations in line with a likely chance of limiting warming to 2°C would be exceeded within just three decades.

Large scale, irreversible changes in the Earth’s systems have the potential to transform whole regions. Examples of risks that are increasing rapidly with warming include degradation of the Amazon rainforest with the potential for large emissions of CO2 due to self-amplifying feedbacks, disintegration of the Greenland and Antarctic ice sheets with multi-meter sea-level rise over centuries to millennia, and large-scale releases of methane from melting permafrost substantially amplifying warming. Recent peer reviewed science shows that a substantial part of the West Antarctic ice sheet, containing about one meter of sea-level rise equivalent in ice, is now in irreversible, unstable retreat.

The buildup of carbon intensive, fossil-fuel-based infrastructure is locking us into a future of CO2 emissions. The International Energy Agency (IEA) has warned, and numerous energy system modelling exercises have confirmed, that unless urgent action is taken very soon, it will become extremely costly to reduce emissions fast enough to hold warming below 2°C.