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
Tag Archives: Extreme Events
11 January 2018, The Conversation, Explainer: ‘bomb cyclones’ – the intense winter storms that hit the US (and Australia too). The eastern United States experienced a very severe winter storm last week, which caused damaging winds, heavy snow and the highest tide on record for Boston. Meteorologists call this type of storm a “bomb cyclone”, or simply a “bomb”. But what is it? A “bomb” is an old meteorological term for a low-pressure system outside the tropics (that is, an extratropical cyclone) that intensifies very rapidly, based on how fast the atmospheric pressure drops at the centre of the storm. A common benchmark is a drop of 24 hectopascals (hPa) over 24 hours, although this varies slightly with latitude. The recent bomb in the US had a reported pressure drop of 59hPa over 24 hours, making it one of the strongest such storms ever recorded. Read More here
11 January 2018, Arctic cause of loopier cold weather? A QUICK SUMMARY: The Science Linking Arctic Warming to This Crazy-Cold Winter: It’s well known that the rapidly warming Arctic is melting sea ice, thawing permafrost, and accelerating sea-level rise. But a growing body of research suggests, counter intuitively, that it could also be amplifying cold snaps, much like the brutal one now freezing the East Coast. ANOTHER VIEW: US cold snap was a freak of nature, quick analysis finds. The cold snap that gripped the East Coast and Midwest region was a rarity that bucks the warming trend, said researcher Claudia Tebaldi of the National Center for Atmospheric Research and the private organization Climate Central.
4 January 2018: The first complete temperature datasets for 2017 show that last year was the third in a row of exceptionally warm years, the Copernicus Climate Change Service (C3S) implemented by the European Weather Centre (ECMWF) can announce. One data set, produced by ECMWF, shows that the global average surface air temperature exceeded 14.7°C, making 2017:
- about 0.1°C cooler than the warmest year on record, 2016, and warmer than the previous second warmest year, 2015
- the warmest year on record not influenced by warming El Niño conditions in the tropical Pacific
- around 0.5°C warmer than the 1981–2010 climatological reference period
- an estimated 1.2°C warmer than the pre-industrial value for the 18th century.
Comparable results have been obtained by C3S from a reanalysis dataset produced by the Japan Meteorological Agency (JMA). The method used to produce the datasets is to combine millions of meteorological and marine observations, including from satellites, with models to produce a complete reanalysis of the atmosphere. The combination of observations with models makes it possible to estimate temperatures at any time and in any place across the globe, even in data-sparse areas such as the polar regions. The results support the provisional announcement by the World Meteorological Organization (WMO) two months ago that 2017 was set to be among the three warmest years on record. Other datasets used in the WMO announcement, which are derived from monthly climatological data for a smaller number of long-term observing sites, are also expected to concur when they are released shortly. All datasets will contribute to the consolidated statement to be issued by WMO on 2017 temperatures. Read More here