29 November 2016, Carbon Brief, Guest post: Misleading media coverage of Antarctic sea ice paper. Dr Jonathan Day is a polar climate scientist at the University of Reading. His work focuses on understanding and predicting changes in sea ice in the Arctic and Antarctic. Last week, my colleague Tom Edinburgh and I published an article estimating the extent of Antarctic sea ice in the early 1900s, using sea ice observations recorded by explorers of the time. It received an overwhelming amount of coverage in the media. This was largely because it combined a human-interest story about the conditions faced by the early Antarctic explorers with an illuminating result regarding the thorny issue of Antarctic sea ice trends. Despite significant increases in global average temperature, sea ice in the Antarctic has been slightly increasing in extent over recent decades (1979 – present). Although much of the coverage was very well reported, there were other examples of the results being wrongfully interpreted, perhaps wilfully so. Some of the errors led to confusion, such as conflating sea ice with land ice. Others attempted to cast doubt on the link between greenhouse gases and global mean temperature, which was inappropriate and misleading. Read More here
Category Archives: Impacts Observed & Projected
28 November 2016, Geophysical Research Letters (REPORT) Pine Island Glacier has undergone several major iceberg calving events over the past decades. These typically occurred when a rift at the heavily fractured shear margin propagated across the width of the ice shelf. This type of calving is common on polar ice shelves, with no clear connection to ocean-ice dynamic forcing. In contrast, we report on the recent development of multiple rifts initiating from basal crevasses in the center of the ice shelf, resulted in calving further upglacier than previously observed. Coincident with rift formation was the sudden disintegration of the ice mélange that filled the northern shear margin, resulting in ice sheet detachment from this margin. Examination of ice velocity suggests that this internal rifting resulted from the combination of a change in ice shelf stress regime caused by disintegration of the mélange and intensified melting within basal crevasses, both of which may be linked to ocean forcing. Read More here
26 November 2016, Climate News Network, Bolivian water crisis as glaciers vanish. Bolivia has declared a state of emergency as climate impacts shrink glaciers and leave cities without water. The government of Bolivia, a landlocked country in the heart of South America, has been forced to declare a state of emergency as it faces its worst drought for at least 25 years. Much of the water supply to La Paz, the highest capital city in the world, and the neighbouring El Alto, Bolivia’s second largest city, comes from the glaciers in the surrounding Andean mountains. But the glaciers are now shrinking rapidly, illustrating how climate change is already affecting one of the poorest countries in Latin America. The three main dams that supply La Paz and El Alto are no longer fed by runoff from glaciers and have almost run dry. Water rationing has been introduced in La Paz, and the poor of El Alto − where many are not yet even connected to the mains water supply − have staged protests. The armed forces are being brought in to distribute water to the cities, emergency wells are being drilled, and schools will have to close two weeks ahead of the summer break President Evo Morales sacked the head of the water company for not warning him earlier of the dangerous situation, but the changes produced by global warming have been evident for some time. Read More here
22 November 2016, The Guardian, ‘Extraordinarily hot’ Arctic temperatures alarm scientists. The Arctic is experiencing extraordinarily hot sea surface and air temperatures, which are stopping ice forming and could lead to record lows of sea ice at the north pole next year, according to scientists. Danish and US researchers monitoring satellites and Arctic weather stations are surprised and alarmed by air temperatures peaking at what they say is an unheard-of 20C higher than normal for the time of year. In addition, sea temperatures averaging nearly 4C higher than usual in October and November. “It’s been about 20C warmer than normal over most of the Arctic Ocean, along with cold anomalies of about the same magnitude over north-central Asia. This is unprecedented for November,” said research professor Jennifer Francis of Rutgers university. Temperatures have been only a few degrees above freezing when -25C should be expected, according to Francis. “These temperatures are literally off the charts for where they should be at this time of year. It is pretty shocking. The Arctic has been breaking records all year. It is exciting but also scary,” she said. Read More here