Pantanal has an alert scenario with floods below average – 01/14/2024 – Environment

After facing a scenario of devastation with historic rates of fires in 2020 and 2023, the Pantanal is still expected to go through difficult times throughout this year. With below-average rainfall, the biome is not flooded and the situation is considered alert.

The Pantanal receives rainwater from the plateau regions, from the Upper Paraguay Basin. In the natural calendar, the cycle begins in October, with peaks in December and January, lasting until March at the latest. During floods, water overflows river channels, connects lakes and forms large, continuous flooded areas.

However, in November 2023, what was seen in the region was fire. The Pantanal recorded 4,134 hot spots, the highest index ever measured by Inpe (National Institute for Space Research) for the period, since 1998. Compared to November 2020, there were 778 hot spots. That entire year, the biome lost 3.9 million hectares in fires that caused worldwide commotion.

In addition to fire, the Pantanal also suffers from climate change. The change in the water cycle can be verified using the century-old ruler of Ladário (MS), installed in the upper part of the Paraguay River Basin, monitored by the 6th Naval District of the Navy, which has records of floods since 1900.

On the 1st of January 2024, the level of the Paraguay River, mainly responsible for flooding in the biome, was 0.31 centimeters. It is rising, but slowly, reaching the current 0.50 centimeters, recorded last Friday (12).

Although it is still too early to estimate the scenario during the dry period, experts are concerned. Embrapa researcher, Carlos Roberto Padovani highlights that the average value of the Paraguay River in Ladário, for the date of January 8th, is 1.59 meters, according to historical data.

“Of the six months of rainy season, looking from October to December, it rained almost nothing. If it rained, it was punctual,” said Padovani. “It’s raining, but not enough to fill the river level,” he said. For overflow, when the river throws water outside the gutter, the minimum to be reached is 4 meters.

According to Padovani, the historical flood average is 5.5 meters. In 2024, the maximum estimate is that the level of the Paraguay River will be 4.5 meters by mid-March, when the flooding calendar in the Pantanal ends. The calculation is slightly better than the result from 2023, when the maximum reached in the year was 4.24 meters.

Late rain

The moderate outlook for 2024 is based on historical indices that show a reduction in precipitation from October to December, when the rainy season regularly begins in the Pantanal.

In 2023, compared to the other years in the data series, since 1981, the drop in October was 28.85%; in November, 29.79% and, in December, 50.65%. The indices were estimated for the plateau sub-basins, in the northern region of the Upper Paraguay Basin. Padovani, however, is cautious.

“The wetland is not flooded, but it is not in crisis, it is not deserted.” The researcher claims that it is still premature to estimate what could happen in the dry season, which begins in May and peaks in September, a time that also increases the risk of forest fires.

The researcher recalls extreme moments in the biome, which went through severe drought from 1962 to 1973 and then the flood of the 1980s, when the level of the Paraguay River reached 6.64 meters in 1988. “When the flood arrived, the drought was considered normal. Now, the process has reversed.”

Padovani believes that the rains from January to March could still have some effect this year and bring floods close to the level of 2023. “But it has to rain in the Upper Paraguay basins, in the north.”

The expectation is based on the inconsistency of the Pantanal: last year, for example, the Paraguay River exceeded 4 meters from June to August, when the rain regime occurred atypically, from January to May, outside the usual water cycle calendar. .

Researcher member of MapBiomas, Eduardo Reis Rosa, has a more critical view and does not believe in significant changes in the scenario. “What was supposed to be filled is gone, a worrying period is coming.”

According to him, the 2023 flood was good, but it was not enough to renew the wetland. “Let’s hope that 2024 still has at least sporadic rain.”

The two researchers also take into account the effects of El Niño, associated with rising temperatures and which is expected to last until April this year, according to a bulletin from the WMO (World Meteorological Organization), published in November 2023. “We must suffer the effects of change climate, but no one knows exactly which ones, whether drier or fuller”, said Padovani.

Rosa warns of the risk of increased deforestation during the dry season and hopes for the application of the Pantanal Law, sanctioned by the government of Mato Grosso do Sul last year and which imposes rules and sanctions for the deforestation of areas in the biome and prohibits construction of dikes or dams, for example.

Fire impact

In 2020, the Pantanal lost 3.9 million hectares to fires, equivalent to 26% of the biome, according to data from Lasa (Environmental Satellite Applications Laboratory) at UFRJ.

This year, in addition to the November fires, another image struck the region. In December, the IHP (Instituto Homem Pantaneiro) caught a cloud of dust that “swallowed” the Serra do Amolar, in the Acurizal region, a phenomenon that lasted around 1 hour and arose from the combination of strong winds and high temperatures, according to meteorological service.

The president of IHP, Ângelo Rabelo, who recorded the phenomenon, stated that this was the second occurrence of the storm in 2023.

“It had already happened, to a lesser extent, but nothing like it. The winds from the northern region of Mato Grosso brought ash from forest fires in the neighboring state, along with the sandstorm. It’s something that scares riverside dwellers and those who live in the region “.

The IHP also adopts caution for the future. The institute’s biologist Wener Hugo Moreno said that it is still too early to make a diagnosis for the flood in the Pantanal, although he has already identified a reduction in the river level index in the Cáceres (MT) ruler, in the comparison between 2023 and 2024.

The report contacted the government of Mato Grosso do Sul to update preventive measures to combat forest fires, but received no response.

Last year, in November, the Mato Grosso do Sul Environmental Institute used satellite images, three aircraft with a capacity of up to 3,000 liters of water and specific trucks for transporting water to put an end to fires.

The fight against the flames also had the support of firefighters living in the surrounding areas, teams from PrevFogo and IHP and with the rain that fell at the end of that month.