The internationally agreed limit to prevent the Earth from spiraling into a new superheated era will be crossed “for all practical purposes” by 2024, the man known as the godfather of climate science has warned. James Hansen, a former NASA scientist credited with alerting the world to the dangers of climate change in the 1980s, said global warming caused by burning fossil fuels, amplified by the naturally recurring El Niño weather event, would raise temperatures by up to 1.7C (3F) above pre-industrial averages by May. This high temperature, measured over the 12-month period to May, will not in itself breach the world's governments' commitment to limit global warming to 1.5°C (2.7°F) above the pre-coal, oil and gas era. Scientists say the 1.5C ceiling cannot be considered exceeded until several years have passed that threshold, which is considered the most likely time. sometime in the 1930s . However, Hansen said that even after the El Niño subsides, which usually increases average global warming, the range of the coming years, combined, will still average around 1.5°C. The warming of the world by greenhouse gas emissions is amplified by downstream effects, Hansen said, such as the melting of the planet's ice, which makes the surface darker and therefore absorbs even more sunlight. (Oliver Milman, The Guardian)