Brazil's coastal cities more vulnerable to climate change

Brazilian cities in coastal areas are more vulnerable to climate change, especially to the sea level rise, but also to such events as heavy rain, storms, floods, and coastal erosion, all of which cause destruction and adversely affect infrastructure in these municipalities.

These were the findings of a special report titled Impacto, vulnerabilidade e adaptação das cidades costeiras brasileiras às mudanças climáticas, which the Brazilian Panel on Climate Change (PBMC) is discussing today (June 5) in Rio de Janeiro. This has been the second report on climate change and cities drafted by the PBMC, a scientific body created by the Ministry of Science, Technology and Innovation and the Environment Ministry in 2009. The first paper was presented during the Conference of the Parties to the UN Framework Convention on Climate Change (COP 22) in Marrakech, Morocco in 2016.

The special report looks at the climate change scenario for Brazil and how coastal cities could be impacted by global warming. According to the study, 18 of Brazil's 42 metropolitan areas are located in coastal regions or within their influence zone. The report covered coastal municipalities in the Northeast, Southeast, and South regions of the country.

Sea level

In the gloomier scenarios discussed in the report, sea levels could rise 40 centimeters by 2050, causing losses of up to $1.2 billion in the 22 largest coastal cities in Latin America. The cost of climate change has not been measured for Brazil specifically.

According to the head of the PBMC's Scientific Committee, Suzana Kahn, who is a professor at the Federal University of Rio de Janeiro, the impact of the sea level and temperature rise is much greater in Brazil, because the country has a significant portion of its cities located along a long coastline. “We can't stop the damages, but we can adopt solutions in the sense that we can adjust to a new reality,” she said.

In addition to the sea level, extreme rainfall events are also among the causes for environmental problems in coastal regions, leading to landslides, torrents, and flooding.

Mapping

Some of the most vulnerable cities include Rio de Janeiro, Santos (São Paulo), Fortaleza (Ceará), Recife (Pernambuco), Salvador (Bahia) and, in Brazil's South region, the Vale do Itajaí region of Santa Catarina, which in addition to the rising sea level, is at risk of becoming a hurricane route. Severe storms in the region, with winds faster than 80 kilometers per hour, suggest that scenario, according to the Executive Secretary of the Panel's Scientific Committee, Andrea Santos.

Measures

The report recommends carrying out new risk analyses that look into associated disasters, increasingly extreme weather, and rising sea level in coastal cities, particularly in the North and Northeast of the country, to help find out which risks the cities and populations are prepared to deal with.

Also recommended are national, state, and local public policies to mitigate these impacts. The Executive Secretary of the Scientific Committee of the PBMC, Andrea Santos, instanced the cities of Rio de Janeiro and Santos, which are “discussing medium and long-term plans, but also have measures in place that can be taken in the short term.”

One of them is the construction of a pool at Praça da Bandeira, an area in downtown Rio de Janeiro that has been flooded several times over the years. Santos said an underground reservoir built there could be considered an adaptive measure, because in practice it has helped prevent new floods.

In addition to protective barriers against the rise in the sea level, Andrea Santos urges coastal cities to protect their ecosystems. Mangroves, for example, provide an important barrier to salt water.

Another basic measure that the population could contribute with is waste disposal. “It would make things easier if the population didn't drop litter on the street,” she recommended.

Translated by Mayra Borges