1 June 2017, The Conversation, Global stocktake shows the 43 greenhouse gases driving global warming. The most comprehensive collection of atmospheric greenhouse gas measurements, published today, confirms the relentless rise in some of the most important greenhouse gases. The data show that today’s aggregate warming effect of carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) is higher than at any time over the past 800,000 years, according to ice core records. Building on half a century of atmospheric measurements by the international research community, we compiled and analysed the data as part of a group of international scientists, led by Malte Meinshausen from the University of Melbourne in collaboration with CSIRO. Together, the data provide the most compelling evidence of the unprecedented perturbation of Earth’s atmosphere. They clearly show that the growth of greenhouse gases began with the onset of the industrial era around 1750, took a sharp turn upwards in the 1950s, and still continues today. Research has demonstrated that this observed growth in greenhouse gases is caused by human activities, leading to warming of the climate – and in fact more than the observed warming, because part of the effect is currently masked by atmospheric pollution (aerosols). The new collection of records comes from measurements of current and archived air samples, air trapped in bubbles in ice cores, and firn (compacted snow). The data cover the past 2,000 years without gaps, and are the result of a compilation of measurements analysed by dozens of laboratories around the world, including CSIRO, the Bureau of Meteorology’s Cape Grim Station, NOAA, AGAGE and the Scripps Institution of Oceanography, among others. Read More here
Category Archives: PLEA Network
28 May 2017, Climate News Network, Antarctica heights settle polar warming puzzle. Computer simulation shows that Antarctica is warming far slower than the Arctic region because of its much greater height. Scientists believe they have settled one of the great polar puzzles − why Antarctica is warming at a rate so much slower than the Arctic region. And the answer is a simple one: Antarctica is so much higher. To ram the point home, they used a computer simulation to hammer the entire southern continent until it was no more than a metre above sea level. At which point, in their simulation, warming at the South Pole became much more dramatic. The two poles are very different: the Arctic is an ocean almost entirely surrounded by land, while Antarctica is a vast continent entirely surrounded by frozen ocean. Landmass of ice As the north polar ocean ice melts, dark seas begin to absorb more radiation. In the southern hemisphere, the landmass of ice reflects radiation back into space to insulate the continent and keep its temperatures far below freezing. But the new study published in Earth System Dynamics journal shows that what makes the biggest difference is the elevation of the surface. Antarctica is not just an enormous continent: thanks to many millions of years of snowfall at very low temperatures, it is banked high with ancient ice. Its average elevation is 2,500 metres − far higher than the highest peaks in the UK, for example − and its highest mountain, Mount Vinson, reaches 4,892 metres, which is higher than any alpine peak in Europe. Evidence from the distant past and climate models both show that, in a warming world, the poles should warm faster than the rest of the planet. But while the Arctic is warming at twice the rate of the rest of the globe, change in Antarctica has been much more sluggish. Read More here
24 May 2017, DeSmogUK, Op-Ed: Glacial Progress at Bonn Climate Talks Shows Why we Need to Exclude Big Polluters From Negotiations. When it comes to the fossil fuel industry participating in UN climate negotiations, it’s clear there is a conflict of interest – and demands for this to end are nothing new. But after fierce resistance to this idea during talks in Bonn last week from the EU, US and Australia, more needs to be done, argues Pascoe Sabido of Corporate Europe Observatory. With just six months to go before November’s COP23 climate negotiations, calls for big polluters to be excluded from the talks are growing. Last May at the same ‘intersessional’ climate talks in Bonn, a group of countries representing more than 70 percent of the world’s population insisted on adding a conflict of interest provision in the negotiating text. It almost made it, were it not for an underhand move by the European Union and the USA which saw it removed. Pulling the strings behind such moves: the world’s largest fossil fuel companies. Taken to its logical conclusion, addressing conflicts of interest would mean kicking out the same corporations whose profits are built on causing climate change. Research shows that at least 80 per cent of known fossil fuel reserves need to be kept in the ground to keep global warming below 2 degrees, let alone 1.5 degrees. But a look at BP and Shell’s future energy projections allege that we can continue to burn fossil fuels indefinitely. Ending fossil fuels would put them out of business. This is a fundamental conflict of interest, yet getting it even discussed – let alone addressed – has been an uphill struggle. However, persistence of those countries at the frontline of climate change – particularly Ecuador, which is seeing increasing water shortages and crop failures – as well as increasing public outrage and civil society’s call on the UN to ‘Kick Big Polluters Out’ of climate policy, has ensured the issue has remained on the agenda. This year’s two-week intersessional talks in Bonn saw an official workshop on the topic organised by the secretariat of the United Nations Convention on Climate Change (UNFCCC). Read More here
23 May 2017, The Conversation, Australian farmers are adapting to climate change. 2016-17 has been a great year for Australian farmers, with record production, exports and profits. These records have been driven largely by good weather, in particular a wet winter in 2016, which led to exceptional yields for major crops. Unfortunately, these good conditions go very much against the long-term trend. Recent CSIRO modelling suggests that changes in climate have reduced potential Australian wheat yields by around 27% since 1990. While rising temperatures have caused global wheat yields to drop by around 5.5% between 1980 and 2008, the effects in Australia have been larger, as a result of major changes in rain patterns. Declines in winter rainfall in southern Australia have particularly hit major broadacre crops (like wheat, barley and canola) in the key southeastern and southwestern cropping zones. There is strong evidence that these changes are at least partly due to climate change. Climate change is affecting farm productivity A recent study by the Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES) confirms that changes in climate have had a negative effect on the productivity of cropping farms, particularly in southwestern Australia and southeastern Australia. In general, the drier inland parts of the cropping zone have been more heavily affected, partly because these areas are more sensitive to rainfall decline. Smaller effects have occurred in the wetter zones closer to the coast. Here less rain can have little effect on – and can even improve – crop productivity. Farmers are reacting However, it’s not all bad news. The study finds that Australian farmers are making great strides in adapting to climate change. Much has been written about the fact that farm productivity in Australia has essentially flatlined since the 1990s, after several decades of consistent growth. The ABARES research suggests that changes in climate go some way towards explaining this slowdown. After controlling for climate, there has been relatively strong productivity growth on cropping farms over the past decade. However, while farms have been improving, these gains have been offset by deteriorating conditions. The net result has been stagnant productivity. Read More here