11 March 2016, Science Daily, Science can now link climate change with some extreme weather events. Extreme weather events like floods, heat waves and droughts can devastate communities and populations worldwide. Recent scientific advances have enabled researchers to confidently say that the increased intensity and frequency of some, but not all, of these extreme weather events is influenced by human-induced climate change, according to an international National Academies of Science, Engineering, and Medicine report released March 11. “In the past, many scientists have been cautious of attributing specific extreme weather events to climate change. People frequently ask questions such as, ‘Did climate change cause Hurricane Sandy?’ Science can’t answer that because there are so many relevant factors for hurricanes. What this report is saying is that we can attribute an increased magnitude or frequency of some extreme weather events to climate change,” said David Titley, professor of practice in Penn State’s Department of Meteorology and founding director of Penn State’s Center for Solutions to Weather and Climate Risk, who chaired the committee that wrote the report. The committee found that scientists can now confidently attribute some heat waves and cold events, and to a lesser degree droughts and extreme rainfall, to human-caused climate change. Even a decade ago, many scientists argued that research could not confidently tie any specific weather events to climate change, which the committee reports today is no longer true today. Read More here
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10 March 2016, The Guardian, Dangerous global warming will happen sooner than thought – study. Australian researchers say a global tracker monitoring energy use per person points to 2C warming by 2030. The world is on track to reach dangerous levels of global warming much sooner than expected, according to new Australian research that highlights the alarming implications of rising energy demand. University of Queensland and Griffith University researchers have developed a “global energy tracker” which predicts average world temperatures could climb 1.5C above pre-industrial levels by 2020. That forecast, based on new modelling using long-term average projections on economic growth, population growth and energy use per person, points to a 2C rise by 2030. The UN conference on climate change in Paris last year agreed to a 1.5C rise as the preferred limit to protect vulnerable island states, and a 2C rise as the absolute limit. The new modelling is the brainchild of Ben Hankamer from UQ’s institute for molecular bioscience and Liam Wagner from Griffith University’s department of accounting, finance and economics, whose work was published in the journal Plos One on Thursday. It is the first model to include energy use per person – which has more than doubled since 1950 – alongside economic and population growth as a way of predicting carbon emissions and corresponding temperature increases. The researchers said the earlier than expected advance of global warming revealed by their modelling added a new found urgency to the switch from fossil fuels to renewables. Read More here
10 March 2016, Climate News Network, Antarctic techno-fix cannot slow rising seas. Pumping seawater onto the Antarctic landmass to form ice and stop sea levels rising stands little chance of success, scientists say. Sea level rise is likely to be a problem too big to handle. Geoengineers will not be able to magic away the rising tides, according to new research. In particular, they will not be able to pump water from the sea and store it as ice on the continent of Antarctica. That is because, unless they pump it enormous distances, that will only accelerate the flow of the glaciers and it will all end up back in the sea again, a study in the journal Earth System Dynamics says. Geoengineering is sometimes produced as the high-technology solution to the environmental problems of climate change: if humans don’t change their ways and start reducing greenhouse gas emissions, say the proponents of technofix, human ingenuity will no doubt devise a different answer. But, repeatedly, closer examination has made such solutions ever less plausible. Scientists have dismissed the idea that the melting of the Arctic can be reversed, have only tentatively conceded that technology could dampen the force of a hurricane, and have found that – instead of cooling the Earth – attempts to control climate change could either make things worse or seriously disrupt rainfall patterns. On balance, scientists believe that most of the big geo-engineering ideas won’t work. Deep freeze And now a team from the Potsdam Institute for Climate Impact Research has poured cold water on the idea of pouring cold water onto the ice cap. The idea is a simple one. Are sea levels rising 3mm a year because the world is warming? Then pump the sea high onto the Antarctic landmass where it will freeze and stay frozen for a millennium. But to be sure of that, say the Potsdam team, at least 80% of the water would have to be pumped 700 km inland. That would take more than 7% of the annual global primary energy supply just to balance the current rate of sea level rise.But even in a world recently committed to a warming of less than 2°C, the seas are going to go on rising. Sea levels could rise at least 40cms by the end of the century – or possibly 130cms, with devastating consequences for low-lying coastlines: rich megacities might be able to build defences, but the poorest communities would be swept away. Read More here
10 March 2016, The Conversation, Global food production threatens to overwhelm efforts to combat climate change. Each year our terrestrial biosphere absorbs about a quarter of all the carbon dioxide emissions that humans produce. This a very good thing; it helps to moderate the warming produced by human activities such as burning fossil fuels and cutting down forests. But in a paper published in Nature today, we show that emissions from other human activities, particularly food production, are overwhelming this cooling effect. This is a worrying trend, at a time when CO₂ emissions from fossil fuels are slowing down, and is clearly not consistent with efforts to stabilise global warming well below 2℃ as agreed at the Paris climate conference. To explain why, we need to look at two other greenhouse gases: methane and nitrous oxide. The other greenhouse gases Each year, people produce about 40 billion tones of CO₂ emissions, largely from burning fossil fuels and deforestation. This has produced about 82% of the growth in warming due to greenhouses gases over the past decade. The planet, through plant growth, removes about a quarter of this each year (another quarter goes into the oceans and the rest stays in the atmosphere and heats the planet). If it didn’t, the world would warm much faster. If we had to remove this CO₂ ourselves, it would cost hundreds of billions of dollars each year, so we should be very grateful that the Earth does it for free. Apart from CO₂, there are two other main greenhouse gases that contribute to global warming, methane (CH₄) and nitrous oxide (N₂O). In fact, they are both more potent greenhouse gases than CO₂. The global warming potential of methane and nitrous oxide is 28 and 265 times greater than that of CO₂, respectively. The human emissions of these gases are largely associated with food production. Methane is produced by ruminants (livestock), rice cultivation, landfills and manure, among others. Read More here