While high temperatures were critical to the melting seen in Greenland last year, scientists say that clear blue skies also played a key role. In a study, they found that a record number of cloud free days saw more sunlight hit the surface while snowfall was also reduced. These conditions were due to wobbles in the fast-moving jet stream air current that also trapped heat over Europe. As a result, Greenland’s ice sheet lost an estimated 600 billion tonnes. Current climate models don’t include the impact of the wandering jet stream say the authors, and may be underestimating the impact of warming. Greenland’s ice sheet is seven times the area of the UK and up to 2-3km thick in places. It stores so much frozen water that if the whole thing melted, it would raise sea levels worldwide by up to 7m. Last December, researchers reported that the Greenland ice sheet was melting seven times faster than it had been during the 1990s.
BBC 15th April 2020 read more »
Violent weather is on the rise. Days of exceptionally heavy rain in São Paulo, Brazil, have multiplied fourfold in one lifetime. In California, autumns have become hotter, and drier, and the risk of devastating wildfires is on the increase. And climate extremes bring with them the risk of ever-greater political conflict. In those countries already politically unstable, one third of all episodes of conflict have started within seven days of a heat wave, landslide, storm or drought. Climate scientists began warning almost 40 years ago that even a small rise in the average annual temperature of planet Earth would be accompanied by a greater frequency of ever more extreme weather events. And now, repeatedly, rainfall, wind speed and thermometer records have begun to provide supporting evidence.
Climate News Network 16th April 2020 read more »