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16 March 2017, The Conversation, Year-on-year bleaching threatens Great Barrier Reef’s World Heritage status. The Great Barrier Reef has already been badly damaged by global warming during three extreme heatwaves, in 1998, 2002 and 2016. A new bleaching event is under way now. As shown in a study published in Nature today, climate change is not some distant future threat. It has already degraded large tracts of the Great Barrier Reef over the past two decades. The extreme marine heatwave in 2016 killed two-thirds of the corals along a 700km stretch of the northern Great Barrier Reef, from Port Douglas to Papua New Guinea. It was a game-changer for the reef and for how we manage it. 

 

Bleaching caused by extreme heat in summer 2016, based on extensive aerial surveys. Category 4 in red: 60-100% of colonies were bleached; Category 3 in orange: 30-60% bleached. Author provided Our study shows that we cannot climate-proof coral reefs by improving water quality or reducing fishing pressure. Reefs in clear water were damaged as much as muddy ones, and the hot water didn’t stop at the boundaries of no-fishing zones. There is nowhere to hide from global warming. The process of replacement of dead corals in the northern third of the reef will take at least 10-15 years for the fastest-growing species. The Great Barrier Reef is internationally recognised as a World Heritage Area. In 2015 UNESCO, the world body with oversight of World Heritage Areas, considered listing the reef as a site “in danger” in light of declines in its health. Australia’s response falling short. Read More here

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1 March 2017, Thomas Reuters Foundation, Antarctica hits record high temperature at balmy 17.5°C (63.5°F). An Argentine research base near the northern tip of the Antarctic peninsula has set a heat record at a balmy 17.5 degrees Celsius (63.5° Fahrenheit), the U.N. weather agency said on Wednesday. The Experanza base set the high on March 24, 2015, the World Meteorological Organization (WMO) said after reviewing data around Antarctica to set benchmarks to help track future global warming and natural variations. “Verification of maximum and minimum temperatures help us to build up a picture of the weather and climate in one of Earth’s final frontiers,” said Michael Sparrow, a polar expert with the WMO co-sponsored World Climate Research Programme. Antarctica locks up 90 percent of the world’s fresh water as ice and would raise sea levels by about 60 metres (200 ft) if it were all to melt, meaning scientists are concerned to know even about extremes around the fringes. The heat record for the broader Antarctic region, defined as anywhere south of 60 degrees latitude, was 19.8°C (67.6°F) on Jan. 30, 1982 on Signy Island in the South Atlantic, it said. And the warmest temperature recorded on the Antarctic plateau, above 2,500 metres (8,202 feet), was -7.0°C (19.4°F) on Dec. 28, 1980, it said. Wednesday’s WMO report only examined the highs. The lowest temperature set anywhere on the planet was a numbing -89.2°C (-128.6°F) at the Soviet Union’s Vostok station in central Antarctica on July 21, 1983. (Reporting by Alister Doyle; Editing by Louise Ireland) Read More here

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17 February 2017, Climate News Network, Canada’s glacial ice loss raises sea level. Dramatic increase in ice loss from the Arctic glaciers of Canada’s northernmost archipelago is now a major contributor to sea level rise. \Glaciers on Canada’s Queen Elizabeth Islands are melting at an ever faster rate. Between 2005 and 2015, ice loss accelerated massively from three billion tonnes a year to 30 billion, according to new research. The islands, which make up Canada’s northernmost archipelago, are home to a quarter of all the Arctic ice − second only to Greenland. And the flow of meltwater there from what once were frozen rivers is now a major contributor to sea level rise. Scientists report in Environmental Research Letters journal that they used satellite data from 1991 to 2015, and ice thickness data from a separate NASAstudy, to calculate ice loss from the Queen Elizabeth Islands. Ice covers 105,000 square kilometres of the archipelago. There are eight ice caps, and altogether 254 glaciers flow into the sea. Glaciers everywhere in the world are in retreat, and researchers warned two years ago that Canada could eventually lose many of its frozen rivers. Read More here

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10 February 2017, Carbon Brief, Guest post: Why NOAA updates its sea surface temperature record. The National Oceanic and Atmospheric Administration (NOAA) is one of a number of climate agencies that pieces together global temperature from thousands of measurements taken each year across the world’s land and oceans. Last weekend, an article in the Mail on Sunday sparked interest in the way NOAA constructs its temperature record. The claims in the article, widely rebutted shortly after its publication, focused on the most recent version of NOAA’s sea surface temperature (SST) record. I have been involved in the development of this dataset since 2011 and it is due to be updated again shortly. However, an early draft of the journal paper about this update appears to have been circulated amongst media without the permission of the authors (including myself). I have, therefore, decided to make some observations here in a personal capacity that may help make better sense of how the dataset is produced and what it shows. Peer review The status of the new version of our dataset – nominally labelled “ERSSTv5” – is that we have submitted a paper to a journal, and it is undergoing peer review. As is the academic norm, the authors wish to respect the review process and did not give their permission for the draft to be shared with the media. To be clear, the authors have expressly not given permission for the draft to be used or quoted in the media. To be equally clear, at this juncture, copyright of the paper remains with the authors. The peer review process on the paper has only just begun, therefore it is premature and incorrect to analyse the dataset in detail before the paper is published. Peer review is an essential step towards eventual acceptance of any new research. It is highly unusual – and, in my view, undesirable – to discuss the specifics of submitted manuscripts in a public manner before this process has concluded. Peer review will, inevitably, point out ideas which shall serve to strengthen any given analysis. I shall, therefore, not be discussing specific scientific aspects of the draft paper and shall refer to it below only to the barest extent required. If and when the paper is published, this will be the appropriate time to discuss its findings in depth and I would be delighted to do so. Read More here

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