27 September 2016, Climate Central, The World Passes 400 PPM Threshold. Permanently. In the centuries to come, history books will likely look back on September 2016 as a major milestone for the world’s climate. At a time when atmospheric carbon dioxide is usually at its minimum, the monthly value failed to drop below 400 parts per million. That all but ensures that 2016 will be the year that carbon dioxide officially passed the symbolic 400 ppm mark, never to return below it in our lifetimes, according to scientists. Because carbon pollution has been increasing since the start of the Industrial Revolution and has shown no signs of abating, it was more a question of “when” rather than “if” we would cross this threshold. The inevitability doesn’t make it any less significant, though. September is usually the month when carbon dioxide is at its lowest after a summer of plants growing and sucking it up in the northern hemisphere. As fall wears on, those plants lose their leaves, which in turn decompose, releasing the stored carbon dioxide back into the atmosphere. At Mauna Loa Observatory, the world’s marquee site for monitoring carbon dioxide, there are signs that the process has begun but levels have remained above 400 ppm. Read more here
Monthly Archives: September 2016
22 September 2016, The Conversation, The Great Barrier Reef’s ‘new normal’ is a forlorn sight. Images of this year’s coral bleaching on the Great Barrier Reef shocked the world. Some tour operators expressed concern that the extensive and sometimes simplistic media coverage would hurt their businesses. The reef was a hot-button issue during the federal election, with both major parties pledging funding for programs to enhance water quality. Some politicians and tour operators expressed optimism about the reef’s ability to recover. It was the culmination of the longest, most extensive and most severe mass coral bleaching event ever recorded – an event that began in the North Pacific in mid-2014. The Great Barrier Reef was not spared, this year experiencing its hottest sea surface temperatures since records began – 29.1℃ in February (1.1℃ above the 1961-90 average), 29.1℃ (1.3℃ above average) in March and 27.8℃ (1.0℃ above average) in April. Evidence of bleaching was found on 93% of the more than 900 individual reefs surveyed that month, with the most severe impacts on the most pristine and isolated reefs of the far north. A preliminary estimate is that 22% of coral has now died, with 85% of these deaths occurring between Cape York and just north of Lizard Island. Read More here
21 September 2016, Climate News Network, Solar cycle not to blame for warming. New research confirms that increased greenhouse gas levels − rather than solar radiation impacts − are the key factor in global climate change. European scientists have dug deep to dismiss once again the old argument that climate change might be a consequence of solar radiation rather than atmospheric chemistry. The world is warming, they confirm, because more greenhouse gases are getting into the atmosphere, and the changes in the solar cycle are not a significant factor. This is not the first such reassurance. Teams of researchers have in the last few years eliminated cosmic radiation as a factor in climate change and confirmed that sunspots, too, can be declared innocent. But in 2011, with backing from the European Co-operation in Science and Technology (COST), scientists set up their own project. They wanted to better understand the relationship between the cyclically changing patterns of sunlight and variations in climate, against a background of global warming. Solar variability The TOSCA project – which stands for “towards a more complete assessment of the impact of solar variability on the Earth’s climate”− is a co-operation involving solar physics, geomagnetism, climate modelling and atmospheric chemistry. The scientists went for a global approach, with 61 researchers from many disciplines working together to examine as many aspects as possible that might link variations in the sun’s behaviour with variations in climate. And they have summarised the story-so-far in a new report. What they identified is solar mechanisms that could alter regional climate, but none that could trigger global warming. Read More here
21 September 2016, Climate News Network, Dire climate impacts go unheeded. New scientific studies address lack of awareness of the adverse economic, social and biodiversity effects that climate change is already having. The social and economic impacts of climate change have already begun to take their toll – but most people do not yet know this. Politicians and economists have yet to work out how and when it would be best to adapt to change. And biologists say they cannot even begin to measure climate change’s effect on biodiversity because there is not enough information. Two studies in Science journal address the future. The first points out that historical temperature increases depress maize crop yields in the US by 48% and have already driven up the rates of civil conflict in sub-Saharan Africa by 11%. Economic growth Hot weather in future could slow global economic growth rates by nearly 0.30 percentage points per year. Almost as surprising, according to Solomon Hsiang, principal investigator in the Global Policy Lab at the University of California, Berkeley, is that nobody seems to be aware of these facts. “People get so used to hot days, since they happen all the time, that they never stop to consider that those days are costing them,” Professor Hsiang says. “But if people used different technologies or organised their lives differently to adapt to their climate, then we might be able to do dramatically better.” Read More here