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
Category Archives: The Science
16 December 2016, The Conversation, Climate change played a role in Australia’s hottest October and Tasmania’s big dry in 2015. Climate change made some of Australia’s 2015 extreme weather events more likely, according to research published today in the Bulletin of the American Meteorological Society. As part of an annual review of global weather extremes, these studies focused on October 2015, which was the hottest on record for that month across Australia. It was also the hottest by the biggest margin for any month. October 2015 was also the driest for that month on record in Tasmania, which contributed to the state’s dry spring and summer, and its bad fire season. El Niño events usually drive global temperatures higher, and 2015 had one of the strongest on record. So were these records due to El Niño, or climate change? The research shows that while El Niño had some influence on Australia’s weather, it was not the only culprit. El Niño packed a punch – or did it? In 2015, a strong El Niño developed, with record high temperatures in the central equatorial Pacific Ocean contributing to 2015 being the hottest year on record globally (although 2016 will smash it). The Indian Ocean was also very warm. El Niño is often associated with warm and dry conditions across eastern Australia, particularly in spring and summer. The new studies found that for Australia as a whole, while El Niño did make the continent warmer, its direct contribution to record temperatures was small. Only in the Murray Darling Basin did El Niño make it more likely that the October 2015 heat would be a record. El Niño also played a small but notable role in the dry October in Tasmania. Read More here
8 December 2016, The Conversation, Climate shenanigans at the ends of the Earth: why has sea ice gone haywire? There is no doubt that 2016 has been a record-breaking year for Earth’s climate. We will have to wait another couple of months for the final tally, but 2016 will be the hottest year in recorded history globally. Average temperatures are well above 1℃ warmer than a century ago. Global average temperatures, and “global warming”, often give the impression of a gradual change in Earth’s climate occurring uniformly across the planet. This is far from the truth – particularly at the ends of the Earth. The Arctic and Antarctic are behaving very differently from the global picture. One particular polar change that has caught the attention of scientists and the media this year has been the state of sea ice. The seasonal growth and decay of sea ice over the Arctic and Southern oceans is one of the most visible changes on Earth. But in the past few months its seasonal progression has stalled, plunging Earth’s sea ice cover off the charts to the lowest levels on record for November. Explaining what has caused this unexpectedly dramatic downturn in sea ice is a tale of two poles. Arctic amplifiers The northern polar region is an epicentre for change in our warming world. On average, the Arctic is warming at around twice the global average rate. This is due to several environmental processes in the Arctic that amplify the warming caused by rising atmospheric greenhouse gas levels. One of these amplifiers is the sea ice itself. …The southern story It’s a different story when we look at the ocean-dominated southern hemisphere. Antarctic climate records point to a delay in some of the effects of “global warming”. The reasons are still debated, partly because of the much shorter climate records that scientists have to work with in the Antarctic. But it is likely that the expansive Southern Ocean is an important climate change dampener that is able to “hide” some of the extra heat being absorbed by our planet beneath the ocean surface where we don’t feel it – yet. Read more here
7 December 2016, Climate Home, UN to extend freeze on climate change geoengineering. Draft documents suggest countries will agree to further ban on large-scale climate techno-fixes, warning risks of damage to biodiversity outweigh potential benefits. Countries should resist the urge to experiment with large scale planetary geoengineering until it’s clear what the consequences of meddling with the oceans or atmosphere may be. That’s the nub of a decision expected to be taken at the UN’s biannual biodiversity summit taking place in Cancun, Mexico this week, emphasising a “precautionary approach” to such projects. With greenhouse gas emissions closing in on levels that could guarantee warming of 1.5C above pre industrial levels and an El Nino-boosted 2016 likely to be the hottest year on record, some scientists are looking to emergency measures. But the UN is sticking to a familiar line: pumping the atmosphere with tiny mirrors to deflect sunlight, boosting the uptake of CO2 in oceans by stimulating plankton growth, or burning wood and pumping the emissions underground could be a bad idea. “We’re concerned that with any initiative regarding the use of geoengineering there needs to be an assessment,” UN biodiversity chief Braulio Ferreira de Souza Dias told Climate Home. “These can have unforeseen results and spin-offs. If you capture carbon in the oceans, this is effective through all the food chains.” Even national risk assessments on individual geoengineering projects would still form an “incomplete basis for global regulation” says the latest iteration of the UN draft decision, echoing previous Convention on Biological Diversity (CBD) decisions in 2010, 2012 and 2014. “More trans-disciplinary research and sharing of knowledge among appropriate institutions is needed,” it says, citing potential impacts on ecosystems and potential ethical issues. Read More here