Brazil is preparing to host The thirtieth United Nations Conference on Climate Change (COP30)It is expected that it will be held in November 2025, in the city of Bilim, Para. One of the topics that are covered during the event will be The effect of increased sea level on the planet.
With progress Climate Over the years, the oceans have become one of the main topics for discussion between organizations that seek to understand the future of the climate.
Even this topic includes the ecosystem of the entire climate change that affects the planet. For example, and Increase temperatures The world contributes to heating the oceans, which causes thus Sea level rise.
In an interview with CNNEduardo Siegel, Deputy Director of the Ocean Institute (IO) Sao Paulo University (USP)He explains that there Two main reasons for increasing sea level: thermal expansion of water and ice rivers. It indicates that the current notes indicate that the sea level has risen more than 20 cm in the last century.
“From the early expectations, the monitoring sea level or even overcoming the worst projection scenarios has reached. That is, the worst expectations have been confirmed so far. For 2050, compared to 2000, sea level must rise between 15 and 35 cm worldwide. In specific areas, where there are landing operations, these values can reach a 30 % increase. ”
Increased sea level affects coastal cities?
any Coastal area The low height, in Brazil or in other parts of the world, will affect the increase in sea level.
As a result, Professor Solge says that many of these areas will face Employment operations Because of the water and the disappearance of coastal environments, such as beaches.
Currently, Brazilian cities like Recif are already facing floods resulting from Mary. However, experts warn of these Coastal floods tend to become more frequent by increasing sea level.
In addition, salt water invasion in coastal areas can give up fresh water reserves in the water level and change the soil properties.
César parbedo Rocha, a professor at the USP Oceanic Institute at the Equipment Institute, says roads, ports, drainage systems and all coastal infrastructure are designed at the past decades level. any, Corrosion caused by high water may affect this infrastructure.
“It is important to highlight that the ocean has absorbed about 90 % of the additional heat resulting from global warming in recent decades. This has helped reduce the increase in the surface temperature, but also increases the sea level and changes the patterns of the peripheral cycle.” CNN.
The main reasons for increasing sea level
- Thermal expansion of water: In the first case, the deputy director of the USP (IO) explains that the increase in temperature causes water to expand, occupy more space in the oceans and raise its level;
- Continentity: The second reason is related Dissolution The floor, which adds more water in the oceans.
How does science measure the level of the sea?
Science monitors changes at sea level through various complementary techniques. According to Siegel, Marégraphs is one of the most common ways. Interested in coastal areas, this equipment records tidal behavior, allowing you to define local differences in sea level over time.
Since the early 1990s, Satellite Also monitor sea level on a global scale High accuracy to provide consistent data on the height of the ocean. There are also GPS stations, which can provide information to correct differences.
Rocha adds that ocean heating is monitored through vessels installed on ships and independent treatments. With a mixture of this data, it can be noticed The average world sea level has increased by about 10 centimeters in the past thirty years The trend that must continue to grow.
The sea rises in Risivi and Santa Katarina
In an analysis issued by the US Space Agency (NASA), scientists have set an increase of 0.59 cm at sea level by 2024. Previous models expected an increase of 0.43 cm, confirming that this height occurs faster than expected.
According to Osvaldo Girão, a professor of graduate degree in geography at Pernambuco Federal University (UFPE), Recife is in geographical position conducive to floods. For this reason, It is one of the Brazilian regions most vulnerable to climate change, especially the increase in sea level.
“When considering the rise in sea level, the city of Recife will be vulnerable to the height that will initially threaten the coastal areas of the center and the Brazilian neighborhoods of Brazilian, Bina and Boa, which threatens the increase and repetition of the river, coastal and coastal,” he said.
Giraau also states that the southern density regions, such as the Florianopiolis Center, have already faced these effects often and intensity.
The latest examples of the flood recorded in Porto Alegre, in Rio Grande de SolIn May 2024, caused by the large size of the rain and the exacerbation of the meteorological tidal and coastal winds.
Professor Cesar Rocha notes that in southern Brazil, especially in Santa Catarina, extremist natural events increase exacerbation of floods and floods.
For example, hurricanes and outside orbital waste cause strong winds, higher waves and a decrease in atmospheric pressure. Factors that contribute to the height of the sea and more coastal floods.
How to adapt to the increase in sea level
Dealing with the climatic consequences of the planet is not simple, so there is no easy answer to solving sea level increase. But experts say there are techniques to reduce extremist scenarios.
Some methods are:
- Transfer of infrastructure and residents: Removing construction and risk population can improve coastal areas protection;
- Restore coastal ecosystems: Restore the mangroves, dunes and population disperses the energy of the waves and capture carbon;
- Rebuilding sand dunes and comfortable plants: Rebuilding these areas restores sediment stocks, enhances the beach and reduces corrosion;
- Rigid work in adhering to dates: Coastal protection work is recommended only when it is indispensable to protect critical infrastructure.
In any case, the accumulated effects of climate change are sufficient to maintain the high sea level for the next centuries.
Our current actions can accelerate or slow down this height. All this depends on how to face climate change. There is still time, and A significant decrease in greenhouse gas emissions is necessary to contain this progress.
Summary in the oceans can be seen from space with satellites