11 January 2018, Yale Climate Connections, Bomb-cyclone’ weather in a warming world. This month’s Yale Climate Connections ‘This is not Cool’ video offers a plain-English science-based response to the inevitable ‘So much for climate change’ weather riddle. With New England, much of the middle Atlantic region, and parts of the southeast extending well into Florida suffering through late December-, early January-punishing cold temperatures, and in a number of places, record night-time lows and heavy snowfalls – the inevitable “so much for global warming” argument seemed certain to arise. On the one hand there were analytical news stories such as The Washington Post’s Capital Weather Gang’s story headlined “Historic ‘bomb cyclone’ unleashes blizzard conditions from coastal Virginia to New England. Frigid air to follow.” There also was President Trump’s “we could use a little more of that good old global warming” tweet from his “balmy Mar a Lago” residence looking forward to a frigidly cold New Years Eve dropping of the 2018 ball at Times Square in New York City. So how then to explain such not-at-all-unusual experience of cold weather temperatures even as the global temperatures continue rising? (One can safely anticipate having to explain cool summer-time daily temperatures in some places as the world continues warming.) To some extent, it’s a simple question of needing to repeatedly explain the difference between weather (short term and local) and climate (long term and global). Read More here

1 January 2018, Independent, Arctic warming linked to wet summers and snowy winters in the UK, scientists warn. Record wet summers and severe snowy weather in winter seen in recent years in the UK could be linked to Arctic warming, scientists have said. The UK has been hit by a number of extreme weather events in the past decade, including heavy rain in summer 2007 and 2012, the record wet and stormy winter of 2013/14 and cold and snowy winters in 2009/10 and 2010/11. Researchers compared data of recent UK extremes with the position of the North Atlantic polar atmospheric “jet stream” – a giant current of air – using a measure called the North Atlantic Oscillation (NAO) index which indicates shifts north and south. The exceptional wet summers, snowy cold snaps and mild stormy winters all corresponded with pronounced negative or positive spikes in readings of the index, showing more extreme north and southward movements of the jet stream. The researchers also linked the jet stream’s altered path – its increasing “waviness” – with a rise in summer months of areas of high pressure remaining largely stationary over Greenland, distorting the path of storms across the North Atlantic. Read More here