11 May 2016, The Conversation, Antarctic ice shows Australia’s drought and flood risk is worse than thought. Australia is systematically underestimating its drought and flood risk because weather records do not capture the full extent of rainfall variability, according to our new research. Our study, published today in the journal Hydrology and Earth System Sciences, uses Antarctic ice core data to reconstruct rainfall for the past 1,000 years for catchments in eastern Australia. The results show that instrumental rainfall records – available for the past 100 years at best, depending on location – do not represent the full range of abnormally wet and dry periods that have occurred over the centuries. In other words, significantly longer and more frequent wet and dry periods were experienced in the pre-instrumental period (that is, before the 20th century) compared with the period over which records have been kept. Reconstructing prehistoric rainfall There is no direct indicator of rainfall patterns for Australia before weather observations began. But, strange as it may sound, there is a link between eastern Australian rainfall and the summer deposition of sea salt in Antarctic ice. This allowed us to deduce rainfall levels by studying ice cores drilled from Law Dome, a small coastal ice cap in East Antarctica. It might sound strange, but there’s a direct link between Antarctic ice and Australia’s rainfall patterns. Tas van Ommen, Author provided How can sea salt deposits in an Antarctic ice core possibly be related to rainfall thousands of kilometres away in Australia? It is because the processes associated with rainfall variability in eastern Australia – such as the El Niño/Southern Oscillation (ENSO), as well as other ocean cycles like the Interdecadal Pacific Oscillation (IPO) and the Southern Annular Mode (SAM) – are also responsible for variations in the wind and circulation patterns that cause sea salt to be deposited in East Antarctica (as outlined in our previous research). By studying an ice record spanning 1,013 years, our results reveal a clear story of wetter wet periods and drier dry periods than is evident in Australia’s much shorter instrumental weather record. Read More here
Tag Archives: Extreme Events
4 May 2016, The Guardian, Fort McMurray: Canada wildfires force evacuation of oil sands city. The entire population of a northern Alberta city has been ordered to evacuate as a wildfire whipped by high winds engulfed homes and sent ash raining down on residents. All of Fort McMurray, with the exception of Parson’s Creek, was under a mandatory evacuation order on Tuesday, said Robin Smith, press secretary for the regional municipality of Wood Buffalo in the Canadian province. More than 80,000 residents were being directed to evacuation centres outside Fort McMurray, but journeys were made difficult as the main road out of the city – Highway 63 – was licked by flames. One evacuation centre, on an island in the Athabasca river, had filled up, Smith said. Entire neighbourhoods were destroyed, emergency officials said, but there were no reports of injuries….. Unseasonably hot temperatures combined with dry conditions have transformed the boreal forest in much of Alberta into a tinder box. The wildfire threat is ranging from very high to extreme. Read More here
21 April 2016, ECOS/CSIRO, Systematically addressing disaster resilience in Australia could save billions. The cost of replacing essential infrastructure damaged by disasters will reach an estimated $17 billion in the next 35 years, according to the latest set of reports from the Australian Business Roundtable for Disaster Resilience and Safer Communities.The reports, Building Resilient Infrastructure and the Economic Costs of Social Impact of Disasters, outline the costs associated with replacing essential infrastructure damaged by disasters and provide an overview of the direct costs of physical damage within the total economic cost of disasters. In 2015, the total economic costs of disasters exceeded $9 billion, a figure that is projected to double by 2030 and reach $33 billion per year by 2050 – funds that could be spent elsewhere on other major national projects. During the Roundtable’s launch of the reports at Parliament House last month, risk expert and CEO of reinsurer Munich Re, Heinrich Eder, noted that these projections are based only on economic and population growth. They do not even include the increasingly detectable effects of climate change. These are big, and socially traumatic, numbers. Long-term they have the same sort of potential to create holes in national and state budgets as our ageing population does—the subject of repeated Intergenerational Reports and eventual decisions about adjusting retirement age. Read More here
4 April 2016, Science Daily, Water cycle instability is here to stay posing major political and economic risks. Adaptation to new risks: A vital necessity for development policies. The current instability and unpredictability of the world water cycle is here to stay, making society’s adaptation to new risks a vital necessity when formulating development policies, a UN water expert warns. Robert Sandford, the EPCOR Chair for Water and Climate Security at the United Nations University’s Canadian-based Institute for Water, Environment and Health (UNU-INWEH), says long-term water cycle stability “won’t return in the lifetime of anyone alive today.” “What we haven’t understood until now is the extent to which the fundamental stability of our political structures and global economy are predicated on relative stability and predictability of the water cycle — that is, how much water becomes available in what part of the year. As a result of these new water-climate patterns, political stability and the stability of economies in most regions of the world are now at risk.” Ontario Lieutenant-Governor Elizabeth Dowdeswell, a former Executive Director of the UN Environment Programme, and UN Under Secretary-General David Malone, Rector of UN University, are among several expert speakers joining Sandford in Ottawa Tuesday April 5 at UNU-INWEH’s day-long 20th anniversary public seminar, “Water: The Nexus of Sustainable Development and Climate Change.” The seminar will focus on national policy changes needed worldwide to achieve global water security — a pre-requisite for reaching the new global Sustainable Development Goals, or SDGs, agreed upon by world leaders in September 2015. Read More here