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Climate Change

Calculated risk

Workshop on weather extremes exposes the challenge of converting scientific information into disaster prevention

Bob McMillan / FEMA PhotoFlooding in an amusement park in New Orleans after Hurricane Katrina in 2005: the tragedy raised North American awarenessBob McMillan / FEMA Photo

It is practically certain (certainty in this case being 99%) that by 2100 there will be an increase in the frequency of hot days and nights in different regions on the planet. With regard to rainfall intensity, on the other hand, which really has increased in various regions, there are questions as to whether the phenomenon is global; available data indicate that forecasts in this direction have a 66% degree of accuracy. Published last March, the Special Report on Managing the Risks of Extreme Events and Disasters (SREX) pointed to these and several other tendencies based on recent scientific knowledge compiled by the Intergovernmental Panel on Climate Change (IPCC). Its results were discussed in a meeting held in the Moise Safra Auditorium, in the Albert Einstein Convention Center in São Paulo, on August 16 and 17,when researchers from various countries also debated strategies for managing impacts and how to take this knowledge to the decision-makers. The workshop, “Managing the risks of extreme weather events and disasters in Central and South America – what can we learn from the IPCC’s Special Report on extremes?” was held by FAPESP and the National Institute of Space Research (Inpe).

“It was clear from the discussions that the interface of scientists with managers and local communities is at a critical point. There’s a lot of ‘noise’ in this communication,” climatologist José Marengo, coordinator of the workshop and a member of the organizing committee of the SREX, told Agência FAPESP. Perhaps the most important recommendation that came out of the debates was that we need to establish new channels of dialogue between scientists and authorities to face up to the risks of disasters due to extreme weather events and to reduce the losses they cause. The need for a more proactive participation of governments in decisions relating to issues like vulnerability to climate change and strategies for adapting were also highlighted by the researchers at the workshop. “Governments have shown that they’re ill-prepared and they’re still being taken by surprise by meteorological events whose frequency and intensity is rising, as the reports show, and that are likely to increase even more in the future,” said Marengo, who is the coordinator of Inpe’s Earth System Science Center and the head of a thematic project that is part of FAPESP’s Program on Global Climate Change (PFPMCG) on the impact of weather extremes on ecosystems and human health in Brazil.

According to the researcher, quite often there are funds for mapping out risk and removing the population in vulnerable areas, but the money ends up being transferred to other areas. “This shows a breakdown in our dialogue with local governments. It’s no secret that the climate is changing and every year people die because of disasters that could be avoided if these resources were applied,” he said.

The way in which scientific information reaches society is frequently different from the way imagined by researchers. “Discussions cropped up in our debates about terms like ‘uncertainty’, which derives from the climate modeling area and whose concept we scientists understand, but which is yet to be suitably translated for the public,” said Marengo. Further confusion surrounds the concept of disaster itself. “It’s not rain that kills people. It’s a combination of rain and families living on hillsides and in precarious residences. There’s no way to put an end to heavy rainfall, but with planning it’s possible to reduce the number of deaths,” stated the researcher. Society’s perception of climate change follows a rationale that is sometimes very different from that of scientists. Marengo cites Hurricane Katrina, which devastated the Southern United States in 2005 and flooded the city of New Orleans, as an example. “When analyzed in isolation one cannot say that Katrina was the result of global changes. But it was this event that awoke the North American population to the problem,” he said.

Scarcity of data
One of the main conclusions of the SREX report, prepared by the IPCC at the request of the Norwegian government and the UN’s International Strategy for the Reduction of Disasters (Eird), is that an increase in the frequency of extreme weather events has been occurring in the world over the last few decades because of climate change. Based on current evidence, the report indicates that most likely there will be an increase in the frequency of hot days and nights over the next few years in different regions of the planet. However, it is uncertain whether some extreme weather phenomena tend to occur on a global scale, because of the scarcity of data. The document indicates doubts about the increase in the frequency of heavy rainfall worldwide, indicating regions where there has been an increase and others where this particular weather event has decreased. There is also a lack of evidence that tropical cyclones have become more frequent, although the rainfall related to these phenomena is, in fact, stronger. Likewise, droughts may be affecting certain regions of the planet more frequently and more intensely, like northeastern Brazil or Mexico, but do not represent a generalized phenomenon on the planet.

038-041_MudancasClimaticas_199For the researchers who produced the report, one of the main challenges was to fine tune the discourse between specialists from different areas. “It was the first attempt to exchange knowledge in a multidisciplinary way,” said Úrsula Oswald Spring, a doctor and professor at the National Autonomous University of México (Unam), who was involved with preparing the SREX and attended the workshop in São Paulo. “Without building a common language it’s impossible to find solutions for the problems presented by climate change.”

Despite uncertainties as to the extent and frequency of extreme weather phenomena in the future, their impact today is already being felt. Data presented by Úrsula Spring showed that women and children are the biggest victims of hurricanes, earthquakes, tsunamis, floods and other extreme events, whether weather-related or not. They represent 68% to 89% of the deaths that occur in these phenomena worldwide. Women account for 72% of the people who live in conditions of extreme poverty, which makes them more vulnerable in disasters. “The role of women is that of looking after people; so they save their children, parents and animals and don’t see the risk they themselves are running,” said Úrsula, who has been researching the theme for ten years. The loss is also much bigger in poor countries: 95% of the deaths from natural disasters occur in developing countries. “For major disasters to happen it’s necessary for the population to be vulnerable and exposed,” said Sebastián Vicuña, a professor from the Catholic University of Chile.

Climatologist Carlos Nobre, who is the Secretary for Research and Development Policies and Programs at the Ministry of Science, Technology and Innovation (MCTI) and a member of the coordinating body of FAPESP’s Program on Global Climate Change (PFPMCG) and of the IPCC, listed studies published by researchers from São Paulo State dealing with the risks due to more frequent heavy rainfall. One of them indicated an increase in the number of areas susceptible to flooding and where there is a great risk of landslides in the São Paulo capital. Another one showed that with urbanization, the areas of heavy rainfall are expanding and this is increasing the risk of contamination by leptospirosis, a disease mainly transmitted by the urine of rodents. On the other hand, research carried out in the Department of Ecology of Paulista State University (Unesp), Rio Claro campus in a partnership with Inpe showed that Campinas and Ribeirão Preto are the two regions in São Paulo State most vulnerable to climate change. The population concentration in Campinas increases the consequences of a flood. In the case of Ribeirão Preto, the region is likely to record higher temperatures over the coming decades. “In some areas, we can see the socio-environmental impacts caused by the acceleration of climate events. These impacts are associated with a greater vulnerability of the population because of the worldwide growth of urbanization and, in particular, in cities in Latin America where this process has occurred over the last few decades in a chaotic way,” Nobre told Agência FAPESP. In Brazil the resources for reconstruction of regions devastated by extreme weather events have evolved very quickly over the last 10 years and exceeded R$ 1.6 billion in 2011, Nobre pointed out. If there are uncertainties about the tendency for rainfall frequency to increase globally, in the case of São Paulo there are no doubts that heavy rains have increased a lot in the city over the last 50 or 70 years, observed Nobre. “Today we have three times more heavy rain than 70 years ago. The evidence that this type of event occurs more often in the São Paulo capital is very well documented,” he said.

The results of the SREX report will be used and updated in the next reports to be published by the IPCC in 2013. According to Marengo, there is still a scarcity of studies on vulnerability to climate change in Brazilian regions. In producing the SREX, the unwritten rule according to which a good scientific study must be published in English in specialized journals was set aside. “We’ve managed to reach a good level in some Brazilian publications, but there’s still a lack of scientific literature published in the country,” said the researcher. Researchers detected a need to increase funding for studies on climate change, with support from government and non-governmental institutions. The groups also recommended strengthening local risk management institutions. “We don’t need to create new institutions; just strengthen those that already exist,” said Marengo.