Yesterday was the hottest day on record and possibly the hottest in 125,000 years. Data from the University of Maine’s Climate Change institute showed the mean global temperature, as measured 2 metres above land, sea or inland water level, was 17.18C – the same as Tuesday and a 0.08-degree increase on the previous record of 17.1C set the day before. Climate change is the main underlying cause but the El Niño effect – itself exaggerated by climate change – is a factor, and so is the time of year. It’s cold in the southern hemisphere, but that is more than offset by heat in the northern hemisphere because land heats up faster and further than ocean and there’s more of it than in the south. At the same time northern hemisphere vegetation growth is sequestering more carbon than is being released, so the number of CO2 parts per million in ambient air as measured by the Keeling Curve is ticking down and will continue to until late September. But that decline will in turn be more than offset by emissions over the northern hemisphere winter. In the meantime air conditioners are accelerating global warming in an energy-intensive feedback loop. The International Energy Agency estimates India alone will install 3.5 billion cheap, inefficient units between now and 2050.
Photograph Climate Change Institute/ University of Maine