The magnitude of the consequences of this event classified it as a disaster. According to FEMA, disaster is “an occurrence that has resulted in property damage, deaths, and/or injuries to a community”. Disaster, however, also presents a social factor. According to Britton, “disaster is a social product. The propensity of disaster is dependent upon the interplay between humans and their use of the physical and social world” and is also “an expression of the vulnerability of human society”. Local authorities also defined this event as a disaster due to human and physical damage never experienced. Teresópolis’s mayor affirmed that this is “the worst catastrophe in the history of the town” (The New York Times) followed by Rio’s environment secretary “the worst catastrophe in the history of the town” (The Guardian). Science helps explain these public statements. Landslides are scientifically called gravitational mass movements (Baggio & Horn) and, in Brazil, these types of geological hazards are mostly associated with exogenous processes with physical, chemical, biological, topographical, climatic, hydrological, and anthropogenic natures. These geomorphological aspects explain the great hazard of gravitational mass movements in a region located 200 meters above sea level (Baggio & Horn). In this region landslides are mostly related to cold front passages and the South Atlantic Convergence Zone (SACZ). SACZ systems, however, have exhibited more intense characteristics than front passages (Seluchi & Chou). By observing aerial images, The Landslide Blog noted that a key factor for these events was slope gradient and less attribution should be placed on cleared land.
Heavy rainfall triggered the landslide but was not the only reason. Unchecked deforestation turning steep slopes into dangerous landslide-prone areas, competing land-uses, intensive exploitation of vegetable production, extensive cattle farming, emerging economic forestry (eucalyptus and pines), tourism, and upper class settlement development also contributed to this calamity (Gaese). Deforestation and agropastoral, for example, exposed the soil and reduced its ability to water infiltration exacerbating the deleterious effects of 300 mm of rainfall within 24 hours causing speed flow of land, mud and detritus exceeding 95 km/h (Baggio & Horn). Even though many blamed the unusual amount of rain and illegally occupied hillsides, hilltops, and riversides with poor foundation quality, physical expansion of urban areas by rapid population growth – the population of Serra Fluminense quadrupled over the last 40 years – had also contributed to the increased vulnerability of the residents (Smyth & Royle). The Landslide Blog pointed out the poor location of settlements as a main factor for exacerbating vulnerability and potentializing risks. Another important aspect is topography. Geologists have explained that tackling rain-induced landslide is considerably challenging because the amount of rain is not the only source to define landslides but as important is the study of hydrological conditions (soil profile characterization, piezometric levels and hydraulic parameters), rain infiltration (pore-water pressures) and water infiltration through the fractured solid-rock transition inducing a rapid development of positive pore water within the soil mass (Gerscovich & Vargas). Other scientists explain that landslides initiation depends on the fluctuation of the groundwater level, on the impact of falling rocks, and on intense rainfall – causing superficial slides. Fluctuation of groundwater induces cyclical variations of the pore water pressure, and consequently of the effective stresses. This variation causes cyclic expansion and contraction of the saprolitic soil, weakening the imbrication of grains and loss of the cementation that may exist. This is called a “fatigue” phenomenon.” (Lacerda)
This disaster caused millions of dollars in damage. Besides the destruction of most of the infrastructure, there were real risks of food price spike in the region (Sky News). Local authorities also had to spend millions on the provision of temporary housing (Demotix). Even with part of water, power, and telephones lines been restored, local units and population were still isolated and deprived of basic services and goods 72 hours after the first landslide (Care International). 800 search-and-rescue workers from the State Civil Defense and firefighters provided immediate assistance. Others could follow but were prevented from the inaccessibility of the area (Care International). This logistic difficulty was created by the natural events themselves but magnified by lack of resilience planning on disaster management. Lack of accessibility turned the Civil Defense into a useless institution as a provider of continuous support to the affected communities (Baggio & Horn). Although geoscientists have warned public authorities about the urgent needs to improve access to the area, these reports were completely ignored multiplying rescue and recovery costs and hindering search and rescue efforts because of continuing rainfall (Baggio & Horn). By not considering scientific advice and disaster planning, public authorities had also to bear with biological and animal losses.
Public authorities as well as grassroots organizations have designed short and long terms solutions to deal with the disaster. In the short-term, the City gave families shelter for up to six months and the Federal government offered to pay the rent of 2,500 families for an indeterminate period, set up a center to register missing persons, and elaborate an immediate plan to relocate families to better organize shelters at churches, warehouses, and stadiums (Demotix). In the medium and long terms, Brazil’s president signed a decree releasing US$460 million in reconstruction funds, promised to remove bureaucratic bottlenecks, register people to help with long-term housing needs, map out and evacuate risk-areas where residents are holding on to their homes, and review the current procedure of cleaning up disasters rather than stopping them from happening (China Daily). Civil Defense officials have said that “we are going to prioritize prevention” by controlling urban expansion pressures, natural resource exploitation, and new processes of land use, especially in areas characterized by mountainous topography (The Christian Science Monitor). Scientists have suggested authorities to identify synoptic patterns of events to guide forecasters and to invest in training on science and technology. These investments would develop tools and provide information not only to promote forest preservation and agricultural development strategies but also to allow meteorologists to identify hazards and to issue potential disasters signs to communities living at risk zones. These promises, however, might be only rhetorical since the federal government had recently cut its budget by almost a fifth for disaster prevention and preparation measures (The Christian Science Monitor). At the civil society level, hundreds of students from neighboring communities volunteered to the Red Cross by donating their time, non-perishables, hygiene products, mattresses, and blankets. Bloggers and social network users promoted a disaster relief movement considered “the largest current ever seen” in the country (Christian Science Monitor).
References
BAGGIO, Hernando; HORN, Heinrich A. “Geological risks in Brazil: The mountainous region of Rio de Janeiro”. Geo-risk management – a German Latin American approach. Heidelberg, 2-7 April 2011. P55-63)
BRITTON, Neil R. “Developing an Understanding of Disaster”. Journal of Sociology August 1986 vol. 22 no. 2 254-271
FEMA. Disaster: “an occurrence that has resulted in property damage, deaths, and/or injuries to a community” (FEMA, Definitions and Terms, Instruction 5000.2, 1990)
GAESE, Harmut. “Biodiversity in Integrated Land-use Management for Economic and Natural System Stability in the Mata Atlântica of Rio de Janeiro, Brazil”. Fachhoschule Köln. University of Applied Sciences Cologne. Final Report
GERSCOVICH, D.M.S, VARGAS JR., E.A., de Campos, T.M.P “On the evaluation of unsaturated flow in a natural slope in Rio de Janeiro, Brazil”. Engineering Geology. Volume 88, Issues 1-2, 22 November 2006, Pages 23-40.
LACERDA, Willy A. “Landslide initiation in saprolite and colluviums in southern Brazil: Field and laboratory observations” Geomorphology. Volume 87, Issue 3, 15 June 2007, Pages 104-119.
SELUCHI, Marcelo E., CHOU, Sin Chan. “Synoptic patterns associated with landslide events in the Serra do Mar, Brazil” Seluchi, Marcelo E., Chou, Sin Chan. Theoretical and Applied Climatology. Volume 98, Numbers 1-2, 67-77, DOI: 10.1007/s00704-008-0101-x
SMYTH, Conor G. and ROYLE, Stephen A. “Urban landslide hazards: incidence and causative factors in Niterói, Rio de Janeiro State, Brazil” Applied Geography. Volume 20, Issue 2, April 2000, Pages 95-118
Care International. “Care in prepared to assist Brazilians left homeless by floods and landslides”.
China Daily. “At least 270 dead Brazil floods, landslides”
Demotix. “Landslides in Brazil seen from space”
MSNBC. “Rain slows Brazil mudslide rescue effort”.
Sky News. “Number Killed in Brazil Floods Tops 500”, Cole, Rob.
The Boston Globe. “Landslides in Brazil”
The Christian Science Monitor. “As Brazil floods death toll rises”
_________________________. “Brazil floods kills at least 350”.
The Guardian. “Brazil landslides’ death toll climbs as rescue teams dig for survivors” < http://www.guardian.co.uk/world/2011/jan/13/brazil-landslides-death-toll-rises> accessed on September 15, 2011
The Landslide Blog. “Before and after: high resolution images of Brazil landslides”
The New York Times. “Death Toll Mounts in Brazilian Deluge”.
________________. “Landslides and Flooding Kill Scores in Brazil”
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