Global Warming Effects Around the World

Recife, Brazil

Top Impact

Oceans (Sea level)

Other Impacts

People (Costs)

Temperature (Ocean)

Highly developed shoreline in Recife, Brazil

Recife's long, beautiful beach and highly developed shoreline are typical of many modern cities in Brazil. However, the narrow beach provides little protection from the sea—and little leeway for sea-level rise.1

Key Facts

Some 3.7 million people,2 live in the Metropolitan Region of Recife, on Brazil's northeast Atlantic coast, and many of them have homes near the coast.3 Scientists estimate that a global sea–level rise of around 2.6 feet (80 centimeters) is likely by 2100—and that as much as 6.6 feet (2 meters) is possible.4 Sea–level rise puts this region and its tourist industry at risk, unless people make well–planned adaptations to higher water levels. Efforts around the world to slow sea–level rise by cutting global warming emissions are also important.

  • Sea level has been rising at an accelerating pace, according to a tidal gauge on the region's coast.5
  • The region's most developed area is built on a coastal plain with an average elevation of only 13 feet (4 meters) above sea level.3 Many homes in poor neighborhoods are almost at sea level, and flooding at high tide is already a problem.6 If a storm surge of 2 feet (61 centimeters) were to arrive when sea level is nearly 3 feet (91 centimeters) higher than today, the extra 5 feet (150 centimeters) of water could ruin homes in these neighborhoods.
  • Storm waves can pluck sand just offshore and deposit it inland. That is the way natural beaches migrate, if no roads or buildings stand in the way. However, the extensive line of high–rise buildings close to the beach leaves no room for natural beach migration from storm waves pounding the coastline near Recife.

Details

The Metropolitan Region of Recife sits along Brazil's northeast Atlantic coast. It encompasses 14 cities, including Recife,2 the capital city of the state of Pernambuco. As of 2010, the population totals some 3.7 million, and is highly concentrated near the coast.3

Tidal gauges on the Brazilian coast often do not provide consistent records. That can reflect the many influences on local or relative sea–level rise, versus global average sea–level rise. These influences include land subsidence or uplift from geological processes; the influence of ocean currents on water temperatures and the resulting height of the sea just offshore; climate-induced warming, which expands ocean water; and the direct addition of water from shrinking land ice.

The Cananéia tidal gauge station on Brazil's southeast coast has provided continuous measurements. At that gauge, mean sea level rose at a rate of 0.17 inches (04.2 millimeters) per year from 1954 to 2006—or a total of nearly 9 inches (more than 22 centimeters).7 That rate of sea–level rise is faster than the historic global rate, which averaged 0.07 inches (1.8 millimeters) per year during the twentieth century—and increased to around 0.12 inches (3.1 millimeters) per year from 1993 to 2003.8,9 And mean sea level at a tidal gauge near Recife rose at a slightly faster rate than at the one in Cananéia from the 1940s to the 1980s, and started to accelerate in the early 1970s.5

A number of factors make this region vulnerable to sea–level rise. Much of the urban area is on a coastal plain, at the juncture of two rivers. This plain has an average elevation of only 13 feet (4 meters) above sea level.3 The area has many homes, businesses, hospitals, and schools. If the region does not invest in adaptation options, flooding is likely to become much more common—and costly.

Recife is known for its warm, sandy beaches. The Boa Viagem beach stretches more than 4 miles (7 kilometers). However, it is a narrow beach, lined with tall high rises. Beaches provide the first line of defense against the power of seawater. But buildings and development close to the beach leave no room for natural beach processes that respond to sea–level rise.

For natural beaches without roads or buildings, storms are the engines that allow barrier islands to migrate upslope and inland. On low–sloping shorelines, a strong storm can create a surge of water and waves—sometimes high enough to destroy dunes and redeposit sand further inland. Wind can then reshape the sand into a new dune. So even as the original beach erodes away, this episodic process redraws the shoreline and allows the beach to eventually reform at a higher elevation.

With high–value property in the way, coastal communities often chose to scoop up the sand tossed over roads and around buildings and deposit it back on the beach. If the dune is forced to stay in the original location, it will eventually be washed away by storms riding high on rising seas. One can think of urban buildings as a cliff face that will lose all the sand in front until the waves start attacking the cliff directly. Given Recife's high level of coastal development, this phenomenon puts homes, hotels, and other businesses at risk, unless people try to protect the coast—or take action to curb the causes of sea-level rise.

In many cities in Brazil, poor families build homes on marginal land that is at higher risk from severe weather and other effects of climate change. In São Paulo and Rio de Janeiro, for example, many people have built homes on steep hillsides subject to severe mudslides in heavy rains.10 In Recife, marginal land is along riverbanks and in wetlands.

Many of the homes in Recife's poor neighborhoods are almost at sea level. People have even built some homes on stilts over the water.11 Flooding at high tide is already a problem, particularly during the rainy season. In May 2011, during a particularly high tide and after heavy rains, water from the river poured through a neighborhood and into a shopping mall.6 This flooding trained a spotlight on the problem.

Recife is home to two large ports, through which businesses in the Northeast Region export some 10 million tons of goods each year.12 Protection and adaptation measures will be needed to preserve these ports as sea level rises.

Part of a Larger Pattern

The fifth–largest country in the world, Brazil has a population of more than 200 million (as of 2011).13 The Brazilian coastline is roughly 5,000 miles (8,000 kilometers) long.14 Population density along the Brazilian coast is intensifying, as industrial development continues to grow, people are drawn to urban areas to work, and the tourist industry expands.15

Other areas along the Brazilian coast (from north to south) that are at risk from sea–level rise include:

  • Belém, Macapá, and São Luís, three capital cities on the northern coast near the Amazon River delta.14
  • Atafona, a town just northeast of Rio de Janeiro that has already lost hundreds of homes to beach erosion. 16
  • Famous beaches in Rio, such as Copacabana, Impanema, and the Barra da Tijuca, with miles and miles of condominiums and hotels.17 (The Barra da Tijuca will be home of the Olympic Village for the 2016 Summer Olympic Games.18)
  • The Santos region of São Paulo, which has a high concentration of oil and gas fields, refinery complexes, and chemical and manufacturing plants.14

What the Future Holds

Sea level has been rising globally since the end of the last ice age, but the rate of that rise has accelerated significantly. From 1993 to 2009, the rate of sea–level rise rose to around 0.13 inches (3.4 millimeters) per year—nearly twice the average for the twentieth century.8,19

Scientists attribute this recent acceleration to human–caused climate change. Oceans expand as they warm, and the Greenland and Antarctic ice sheets and glaciers add water to the oceans as they shrink.4

After looking closely at the volume of water that could come from glacial and ice sheet melt by 2100, scientists calculate that a rise of 2.6 feet (80 centimeters) is a reasonable estimate—and that as much as 6.6 feet (2 meters) is possible, depending on the pace at which emissions of heat–trapping gases are released.4

Some countries are already paying the price of climate change, as they repair beaches lost to erosion that stems partly from the accelerated global rise in average sea level. In 2009, Mexico launched a project to restore beaches near Cancun, at a cost of about $10 million per mile ($6.2 million per kilometer).20 Given that much of the development along the coast of Recife depends on the beach for protection—and on enticing tourists—maintaining the beach will be important to the region's economy. As sea level rises, that could get expensive.

The height of high tides in Recife ranges from 5 to 8 feet (1.5 to 2.4 meters). 21 If mean sea level rose another 2 to 6 feet (0.8 to 2 meters), which scientists say is possible,4 high tides would be that much higher, and neighborhoods could be flooded regularly. Homes along tidal rivers will be the first to be affected. Leaders of Recife have already been considering building new apartments on safer ground, so people could move out of harm's way.16

Sea–level rise puts this region—as well as many others along the coast of Brazil—at risk unless they make well–planned adaptations to higher water levels. The steep cost of these measures could drop if people around the world make significant efforts to curb their heat-trapping emissions. If we reduce the activities that overload the atmosphere with carbon—the root cause of accelerated global sea–level rise—we can slow the pace of change and give coastal communities more time to prepare for the changes ahead.

Credits

Endnotes

  1. Photograph by Márcio Cabral de Moura: Online at http://www.flickr.com/photos/mcdemoura/3081529586/in/gallery-60971062@N03-72157626672252799/. Accessed February 9th, 2012.
  2. Instituto Brasileiro de Geografia e Estatística. 2010. Censo demográfico, tabela 2.1. Online at http://www.censo2010.ibge.gov.br/sinopse/index.php?uf=26&dados=1. Accessed February 9th, 2012.
  3. Costa, M.B.S.F., et al. 2010. Vulnerability and impacts related to the rising sea level in the Metropolitan Center of Recife, Northeast Brazil. Pan-American Journal of Aquatic Sciences 5(2):341–349. Online at http://www.panamjas.org/pdf_artigos/PANAMJAS_5(2)_341-349.pdf. Accessed February 9th, 2012.
  4. Pfeffer, W.T., et al. 2008. Kinematic constraints on glacier contributions to 21st–century sea–level rise. Science 321 (1340). doi:10.1126/science.1159099.
  5. Harari, J., and R. de Camargo. 1994. Tides and mean sea level in Recife (PE): 8o 3.3'S, 34o 51.9'W, 1946 to 1988. Boletim do Instituto Oceanográfico. Universidade de São Paulo.
  6. Baltar, S. 2011. 2011. Eyewitness report with photographs. Online at http://www.flickr.com/photos/ithappens/5708549882/in/set-72157626568670727/. Accessed February 9th, 2012.
  7. National Oceanic and Atmospheric Administration, Center for Operational Oceanographic Products and Services. Tides and currents: Cananeia, Brazil Station, 874–051. Online at http://tidesandcurrents.noaa.gov/sltrends/sltrends_global_station.shtml?stnid=874-051. Accessed February 9th, 2012.
  8. Bindoff, N., J. Willebrand, V. Artale, A. Cazenave, J. Gregory, S. Gulev, K. Hanawa, C. LeQuéré, S. Levitus, Y. Nojiri, C.K. Shum, L.D. Talley, and A. Unnikrishnan. 2007. Observations: Oceanic climate change and sea level. In: Climate change 2007: The physical science basis: Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, edited by S. Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H. L. Miller. Cambridge, UK, and New York, NY: Cambridge University Press, pp. 385–432.
  9. Douglas, B.C. 1997. Global sea rise: A redetermination. Surveys in Geophysics 18:279–292. doi:10.1023/A:1006544227856.
  10. BBC News. 2011. Brazil flood and mudslide deaths rise as rescue goes on. Online at http://www.bbc.co.uk/news/world-latin-america-12180079. Accessed February 9th, 2012.
  11. Google Earth. Example of a favela in Recife, Brazil. Coordinates: -8.069167°; -34.887439°.
  12. Marengo, J. A., et al. 2009. Climate change and extreme events in Brazil. Fundação Brasileira para o Desenvolvimento Sustentável and Lloyds Brazil. Online at http://www.lloyds.com/~/media/2ce4a37d36fd4fceab4c3fc876f412f7.ashx. Accessed February 9th, 2012.
  13. CIA World Factbook. Washington, DC. Online at https://www.cia.gov/library/publications/the-world-factbook/rankorder/2119rank.html. Accessed February 9th, 2012.
  14. Nicolodi, J.L., and R.M. Petermann 2010. Potential vulnerability of the Brazilian coastal zone in its environmental, social, and technological aspects. Pan–American Journal of Aquatic Sciences 5(2):184–204.
  15. Zamboni, A., and J.L. Nicolodi, eds. 2008. Macrodiagnóstico da zona costeira e marinha do Brasil. Brasília: Ministério do Meio Ambiente. As cited in: Urbanization, vulnerability, and adaptive capacity to climate variability and change on the northern coast of the state of São Paulo, Brazil, R. D'Almeida Martins, et al., 2011. Paper presented at the Colorado Conference on Earth System Governance, Fort Collins, CO, USA.
  16. Reuters. 2010. Brazilian town is being swallowed by the ocean. November 24. Online at http://www.theweathernetwork.com/news/storm_watch_stories3&stormfile=brazilian_town_is_being_swal_241110. Accessed February 9th, 2012.
  17. Rio.com. No date. Tourist and travelers guide to Rio de Janeiro. Online at http://www.rio.com/practical-rio. Accessed February 9th, 2012.
  18. Rio 2016 Summer Olympics. No date. Online at http://www.rio2016.org.br/en/home#. Accessed February 9th, 2012.
  19. Nerem, R.S., D. P. Chambers, C. Choe, and G.T. Mitchum. 2010. Estimating mean sea level change from the TOPEX and Jason altimeter missions. Marine Geodesy 33 (1). Online at http://www.informaworld.com/10.1080/01490419.2010.491031. Accessed February 9th, 2012.
  20. Stevenson, M. 2010. Man, climate combine to erode Cancun's beaches. Associated Press. December 1. Online at http://www.physorg.com/news/2010-11-climate-combine-erode-cancun-beaches.html. Accessed February 9th, 2012.
  21. Mobile Geographics. 2011. Tide table: Recife, Brazil. Online at http://www.mobilegeographics.com:81/calendar/year/5254.html. Accessed February 9th, 2012.
Climate Hot Spots
 
Africa
 
Asia
 
Australia & New Zealand
 
Europe
 
Latin America
 
North America
 
Polar Regions
 
Small Islands
 
Key to top impacts color code