28 August 2017, The Conversation, Is Hurricane Harvey a harbinger for Houston’s future? Over the past week we have seen two major tropical storms devastate different parts of the world. First Typhoon Hato struck Hong Kong and Southern China killing at least a dozen people. And over the weekend Hurricane Harvey made landfall from the Gulf of Mexico, bringing extremely heavy rain to southern Texas and causing devastating floods in Houston. Tropical cyclones are, of course, a natural feature of our climate. But the extreme impacts of these recent storms, especially in Houston, has understandably led to questions over whether climate change is to blame. How are tropical cyclones changing? Tropical cyclones, called typhoons in the Northwest Pacific and hurricanes in the North Atlantic, are major storm systems that initiate near the Equator and can hit locations in the tropics and subtropics around the world. Read More here
Category Archives: The Science
28 August 2017, Climate Home, Link between Hurricane Harvey and climate change is unclear. Reports the devastating storm was made worse by humanity’s carbon emissions fail to grasp climate change is not just about warming. The unprecedented amount of rainfall accompanying Hurricane Harvey immediately raised the question whether and to what extent climate change is to blame. In a warming world the vapour capacity of the atmosphere increases, and more extreme rainfall, like Texas is witnessing right now, is to be expected as a result. This leads many to conclude that climate change exacerbated the impacts of hurricane Harvey. It is very appropriate to highlight that this is the kind of event we expect to see more of in a warming world. However, to apply this argument directly and attribute (and quantify) the impacts from Harvey itself to human-induced climate change, neglects that climate change is not just about warming. In a changing climate, two effects come together: not only does the atmosphere warm up (thermodynamic effect) but the atmospheric circulation, which determine where, when, and how weather systems develop, can change as well (dynamic effect). Read More here
28 August 2017, Climate Home, Link between Hurricane Harvey and climate change is unclear. Reports the devastating storm was made worse by humanity’s carbon emissions fail to grasp climate change is not just about warming. The unprecedented amount of rainfall accompanying Hurricane Harvey immediately raised the question whether and to what extent climate change is to blame. In a warming world the vapour capacity of the atmosphere increases, and more extreme rainfall, like Texas is witnessing right now, is to be expected as a result. This leads many to conclude that climate change exacerbated the impacts of hurricane Harvey. It is very appropriate to highlight that this is the kind of event we expect to see more of in a warming world. However, to apply this argument directly and attribute (and quantify) the impacts from Harvey itself to human-induced climate change, neglects that climate change is not just about warming. In a changing climate, two effects come together: not only does the atmosphere warm up (thermodynamic effect) but the atmospheric circulation, which determine where, when, and how weather systems develop, can change as well (dynamic effect). Changes in the atmospheric circulation can increase the thermodynamic effect (as we saw during floods Louisiana in 2016) or act in the opposite direction to the thermodynamic effect, leading to locally decreasing the risk of extreme rainfall or canceling the effect of the warming alone (examples here). Dynamical factors and thermodynamic aspects of climate change can interact in complex ways and there are many examples where the circulation is as important as the thermodynamics. Read More here
14 August 2017, ECOS, Mapping fire-prone areas before the fires. Two months after Portugal’s deadliest fire season in recent record, thousands of firefighters have again been deployed in the last few days to battle new wildfires. It’s a crisis Australia knows well from its own bushfire history which paints an equally bleak and devastating picture. Events such as Ash Wednesday in Victoria and South Australia in the 1980s, Black Saturday in Victoria in 2009 and the enduring 2001 Black Christmas in NSW, resulted in hundreds of lives lost and close to 5,000 homes destroyed. These are just three examples of a long list of major Australian bushfire events. As we head towards 2050, climate change is predicted to cause fire seasons to start earlier, end later and involve more frequent extremes of weather that support major loss events. More than ever before, planning and preparation is playing a significant role in mitigating major bushfires and their effects on lives, properties and infrastructure. Following a state-wide project that saw CSIRO develop mapping technology that identified bushfire prone areas in Queensland down to a 25 metre square area, our researchers have now stepped onto the international stage by mapping regions all over the world that have conditions susceptible to fire events. This latest global tool is a valuable resource for hazard analysts, financers, developers and even the general public, seeking bushfire information online. Read More here