16 February 2017, The Conversation, Climate change doubled the likelihood of the New South Wales heatwave. The heatwave that engulfed southeastern Australia at the end of last week has seen heat records continue to tumble like Jenga blocks. On Saturday February 11, as New South Wales suffered through the heatwave’s peak, temperatures soared to 47℃ in Richmond, 50km northwest of Sydney, while 87 fires raged across the state amid catastrophic fire conditions. On that day, most of NSW experienced temperatures at least 12℃ above normal for this time of year. In White Cliffs, the overnight minimum was 34.2℃, a new record for the state’s highest observed minimum temperature. On Friday, the average maximum temperature right across NSW hit 42.4℃, beating the previous February record of 42.0℃. The new record stood for all of 24 hours before it was smashed again on Saturday, as the whole state averaged 44.0℃ at its peak. At this time, NSW was the hottest place on Earth. A degree or two here or there might not sound like much, but to put it in cricketing parlance, those temperature records are the equivalent of a modern test batsman retiring with an average of over 100 – the feat of outdoing Don Bradman’s fabled 99.94 would undoubtedly be front-page news. And still the records continue to fall. Mungindi, on the border with Queensland, broke the NSW record of 50 days in a row above 35℃, set just four years ago at Bourke Airport, with the new record now at 52 days. Meanwhile, two days after that sweltering Saturday we woke to find the fires ignited during the heatwave still cutting a swathe of destruction, with the small town of Uarbry, east of Dunedoo, all but burned to the ground. Read More here
Category Archives: Impacts Observed & Projected
14 February 2017, Think Progress, Sinking from drought, California is now also flooding. After weeks of rain, Northern California’s surface water systems have been pushed to the breaking point, even while the effects of a five-year drought continue to threaten the state’s long-term groundwater supplies. More than 180,000 people were evacuated Sunday afternoon after spillways for the Oroville Dam in Northern California showed signs of possible collapse. The potential flooding comes as California begins to emerge from its historic, drought. But despite the overabundance of water on the surface, drought conditions underground have likely had a permanent impact on the state. Even under the best conditions, it could take half a century for underground reservoirs to refill. Recent analysis from the California Institute of Technology shows that drought — combined with water use — has caused parts of California to sink, perhaps permanently. Some places show up to two feet of subsidence over the past two years. That’s because as surface water from rain and snowmelt has decreased, farmers have been using more groundwater from reservoirs. “Subsidence caused by groundwater pumping in the Central Valley has been a problem for decades,” write the authors of a new study, which uses NASA data to track California’s sinking. Pumping groundwater reduces the support below-ground aquifers give to the surface, causing it to sink. In recent years, that process has been sped up, as California’s drought has reduced the surface water available to farmers. While surface water can come in the form of rain, or snowmelt, groundwater sits in aquifers and is the result of a slow build up of water below ground. Read More here
21 December 2016, Climate Central, The U.S. Has Been Overwhelmingly Hot This Year. In a politically divisive year, there’s been one tie that has bound most of the U.S. together. We all live in the United States of Warming (USW! USW! USW!). In all likelihood, the U.S. is going to have its second-hottest year on record, trailing only 2012. Every state is slated to have a top 10 warmest year and even at the city level, unrelenting warmth has been the main story in 2016. Climate Central conducted an analysis of more than 1,730 weather stations across the Lower 48 that include daily temperature data up until Dec. 15. A paltry 2 percent are having a colder-than-normal year. That leaves 98 percent running above normal. Not only that, 10 percent of those weather stations are having their hottest year on record. Those record-hot places can be found from coast to coast. They include medium-sized cities like Asheville, N.C., Modesto, Calif., and Flint, Mich., as well as lesser-known locales like Neosho, Mo., Callahan, Calif., and Climax, Colo. While some of the heat was driven by the super El Niño earlier this year, that alone doesn’t explain all the records being set, particularly in the latter half of the year after El Niño faded. Climate change has caused the U.S. average temperature to increase about 1.5°F since the 1880s. Read More here and to access graphics
21 December 2016, Climate News Network, Antarctic rifts launch giant icebergs. Satellite images reveal clue to the hidden cause of fractures in Antarctic shelf ice that are calving huge icebergs into the south polar seas. Scientists in the US have identified an ominous trend in the Southern Ocean − the creation of enormous icebergs as rifts develop in the shelf ice many miles inland. And although three vast icebergs have broken from the Pine Island glacier in West Antarctica and drifted north in this century alone, researchers have only just worked out what has been going on. Their first clue came from a telltale shadow in the south polar ice, caught by a NASA satellite and visible only while the sun was low in the sky, casting a long shadow. It was the first sign of a fracture 20 miles inland, in 2013. Two years later, the rift became complete and the 580 sq km iceberg drifted free of the shelf. Significant collapse “It’s generally accepted that it’s no longer a question of whether the West Antarctic Ice Sheet will melt − it’s a question of when,” says study leader Ian Howat, a glaciologist in the School of Earth Sciences at Ohio State University in the US. “This kind of rifting behaviour provides another mechanism for rapid retreat of these glaciers, adding to the probability that we may see significant collapse of West Antarctica in our lifetimes.” The scientists report in Geophysical Research Letters journal that they had discovered that although shelf ice could be expected to wear at the ocean edge, something else was happening in West Antarctica. The Pine Island glacier is grounded on continental bedrock below sea level, which means that warming ocean water could penetrate far inland beneath the shelf, without anyone being conscious of any change. Read More here