24 July 2017, Climate Central, A Nebraska-Sized Area of Forest Disappeared in 2015. A Nebraska-sized chunk of the world’s forests was decimated in 2015 because of wildfire, logging and expanding palm oil plantations, according to a new study. The loss is part of a continuing trend of deforestation that could have devastating implications for the climate. About 49 million acres of forest disappeared worldwide in 2015, mainly in North America and the tropics, putting the year’s global deforestation level at its second-highest point since data gathering began in 2001. In all, the globe lost 47 percent more forested land in 2015 than it did 16 years ago, according to the study by Global Forest Watch. Deforestation accounts for more than 10 percent of the global carbon dioxide emissions driving climate change. Dense tropical forests are also critical to keeping the climate stable because they suck up large amounts of human carbon pollution from the atmosphere, storing it in tree trunks, leaves, roots and soil. Using satellite data provided by Google and the University of Maryland, Global Forest Watch researchers measured the death or removal of trees at least 16 feet tall. 2014 was a record-breaking year for tree-cover loss when nearly 60 million acres of forests disappeared. 2015 saw less, but it’s too soon to say whether deforestation is truly on a downward swing because of uncertainty in some of the data, study co-author Mikaela Weisse, a research analyst for Global Forest Watch at the World Resources Institute, said. Read More here
Category Archives: Ecosystem Stress
28 June 2017, Climate Home, Even Boeing-747 tanker jets can’t win our total war on fires. The more effectively we suppress fires, the worse they become. As climate change makes the world more combustible, we need a new approach. In 1910 Ed Pulaski, a US Forest Service ranger, rounded up his men who were fighting a forest fire in dense conifer forests in northern Idaho and forced them, some at gunpoint, to take refuge in an abandoned mine shaft. The Pulaski tunnel (now a tourist site) represents the dramatic historical moment when ad-hoc approaches to controlling wildfire were shown to be utterly inadequate – this heroic failure provided the impetuous for the US Forest Service to declare total war on fire. Nearly all of Pulaski’s men survived the conflagration, one of thousands of fires that burnt across Idaho during an extremely hot and dry summer, an event now known at the ‘Big Burn’. The sheer ferocity, geographic scale and destructive power of the 1910 Idaho fires shifted the focus of the US Forest Service (USFS) from forestry toward fire fighting. This led to the development of networks of fire towers to identify wildland ignitions. They would be extinguished by teams of trained forest fire fighters, many of whom use a combined ax and mattock invented by, and named after, Ed Pulaski.The iconic mascot Smokey Bear was created by the US advertising industry to promote forest fire awareness. The USFS fire fighting policy evolved to a mandated extinguishment of any new forest fire ignition by 10am the following day, with some managers demanding that the fire size was kept below 10 acres. This total war on fire also drove innovation. In the early 1960 the USFS established Fire Lab at Missoula where an aeronautic engineer, redeployed after the defence department project he was working on was cancelled, developed the first mathematical description of fire, creating the foundation for predictive fire behaviour modelling….But there is a very big catch. The US approach is proving to be ecologically and economically unsustainable – especially in an era of increasing fire threat due to climate change.1 Total fire suppression has created the ‘fire suppression paradox’: the more effective suppression is the worse fires become. Fuel that would historically have been burnt by lightning or indigenous people builds up, resulting in catastrophic fires that are uncontainable regardless of the available technology. The fire suppression paradox also has another unintended and counterproductive consequences: communities come to believe flammable landscapes are safe, resulting in increasing urban sprawl into wildlands that are primed to burn. This massively increases the risk of loss of life and property and the inevitable, tragic loss drives further investment into aerial fire fighting. Climate change is turbo-charging this feedback – fire seasons are worsening, fire disasters are becoming more destructive, and hence demands for more investment in aggressive fire fighting are growing worldwide. Collectively this is creating a dangerous and economically and ecologically unsustainable fire-suppression spiral. Read More here
10 May 2017, Climate News Network, Ocean oxygen decline greater than predicted. Circulation changes caused by warming waters and melting polar ice are the most probable explanations for the rapidly falling levels of oxygen in the ocean. US scientists who have been warning that warmer oceans are more likely to be poorer in dissolved oxygen have now sounded the alarm: ocean oxygen levels are indeed falling, and seemingly falling faster than the corresponding rise in water temperature. That colder water can hold more dissolved gas than warmer water is a commonplace of physics: it is one reason why polar seas are teeming with marine life and tropical oceans are blue, clear and often relatively impoverished. In 2013, an international consortium of marine scientists warned that oxygen levels in the oceans could fall by between 1% and 7% by the century’s end. And this could, other scientists predicted, lead to what they politely called “respiratory stress” for some marine life. Ocean warming Ocean ecologists in the US and Germany warned last year that parts of the deep oceans were already showing signs of oxygen deprivation with corresponding dead zones. Earlier this year, another research group looked at the computer simulations for the years 1920 to 2100 and predicted that the hazards were likely to increasewith warming. Now the team have returned to the issue. They report in Geophysical Research Letters that they looked at data for the last 50 years and found the oxygen levels started dropping in the 1980s, as ocean temperatures began to climb – and falling unexpectedly rapidly. The trend of oxygen falling is about two to three times faster than what we predicted from the decrease of solubility associated with ocean warming,” says Takamitsu Ito, of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology, who led the study. “This is most likely due to the changes in ocean circulation and mixing associated with the heating of the near-surface waters and the melting of polar ice.” Read More here
5 April 2017, ECOS, Before the storm. It’s a catastrophe in anyone’s book, not least those of insurance companies anticipating the tens of thousands of claims likely to be lodged.As the floods surged south in the days after Cyclone Debbie hit landfall near Bowen in north Queensland on March 28, a natural disaster was declared in five major centres in northern New South Wales.Citing the chairman of the Insurance Council of Australia, the Australian Financial Review said “in insurance terms, a catastrophe means a disaster that causes a significant number of claims in a region” and for Cyclone Debbie that could be claims over $1 billion. CSIRO’s Dr Chi-Hsiang Wang and colleagues have been researching the cost implications of extreme weather events but with a focus at the other end – predicting the likely cost before the storms. Counting the cost of extreme events Deloitte Access Economics last year delivered a report on building resilient infrastructure which estimated that, between 2002-03 and 2010-11, an annual average of more than $450 million was spent by Australian governments on restoring essential public infrastructure following extreme weather. If it’s business-as-usual, the report said, $17 billion is expected to be spent on direct replacement costs of essential infrastructure due to natural disasters between 2015 and 2050. These estimates don’t factor in the impacts of climate change. In the case of Cyclone Debbie, the wind intensity exceeded the limitations of the building specifications. “It’s not a surprise that we see considerable damage because the intensity is so high,” says Dr Wang. Until now, a cyclone with the force of Debbie was considered a once in a 2,000 year event by Australian design standard for wind actions (AS/NZS 1170.2:2011). That may change. “There’s a consensus among scientists, although not as strong as the consensus around rising global temperatures, that for some tropical cyclone basins around the world they are likely to see events of increased intensity,” he adds. What’s missing? Dr Wang says the current practice for wind impact assessment of physical infrastructure uses only wind intensity (in terms of wind gust) to gauge the damage potential of windstorms. “This ignores other threats brought upon by the accompanying rainfall and storm surge,” he says. Read More here