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
Yearly Archives: 2018
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.
10 January 2018, CSIRO-ECOS, Scientist’s 30-year search for Southern Ocean climate secrets. After more than 24 hours the ice breaker still hadn’t managed to break through the heavy sea ice and Chief Scientist Dr Steve Rintoul had secretly given up hope. All that would change in seconds though, leading to the senior scientist’s greatest but most disturbing discovery of his 30 year career. It was January 2015 when Rintoul and his team aboard the RSV Aurora Australis achieved what no others had managed – reaching the front of the Totten Glacier. They found that warm water was flooding into the cavity beneath the floating ice, melting what was thought to be a stable area of East Antarctica. The sea level rise problem had just got worse. wo years on, Rintoul will return to the Southern Ocean aboard CSIRO’s research vessel Investigator, this time further east towards the Mertz Glacier, on an expedition to piece together some of the remaining unknowns of the climate-critical region. With a physics degree from Harvard, post-graduate qualifications from MIT and Woods Hole, a post-doctorate from Princeton, and decades of experience in Southern Ocean research, Rintoul is more than qualified to lead the voyage. Read More here
5 January 2018, Science Journal, Beneath the waves, oxygen disappears. As plastic waste pollutes the oceans and fish stocks decline, unseen below the surface another problem grows: deoxygenation. Breitburg et al. review the evidence for the downward trajectory of oxygen levels in increasing areas of the open ocean and coastal waters. Rising nutrient loads coupled with climate change—each resulting from human activities—are changing ocean biogeochemistry and increasing oxygen consumption. This results in destabilization of sediments and fundamental shifts in the availability of key nutrients. In the short term, some compensatory effects may result in improvements in local fisheries, such as in cases where stocks are squeezed between the surface and elevated oxygen minimum zones. In the longer term, these conditions are unsustainable and may result in ecosystem collapses, which ultimately will cause societal and economic harm. Read More here