Drought in the Amazon: Rio Negro Reaches its Lowest Level and Makes Ancient Cave Paintings Reappear

This time, the strong drought that has been affecting the Amazon region has caused the reappearance of ancient rock engravings on the rock walls of an archaeological site in Manaus, due to the low level of the Rio Negro.

Image on the left: Rio Negro full (Credit: Amazon Network) and image on the right: Rio Negro during this year's drought (Credit: Michel Castro/Amazon Network).

There are several impacts that the strong drought has been causing in the Northern Region of Brazil, as we have already reported here. On Monday (16), Manaus, the capital of Amazonas, recorded its worst drought in 121 years, with the Rio Negro marking 13.59 meters. According to data from the Port of Manaus, this is the lowest record since 1902, when the measurements began to be carried out.

The last time the level of the Rio Negro, in Manaus, reached such a low level was on October 24, 2010, when the recorded ebb was 13.63 meters.

The drought in the Amazon has everything to be the largest ever recorded in the state. The vast majority of municipalities have already been affected, more than 112,000 fishermen suffer losses and about 500,000 people should be without access to drinking water and food. The Santo Antônio hydroelectric plant interrupted its operations after registering a flow rate 50% below the historical average of the Madeira River.

Millennial engravings on display

Due to its low level, the Rio Negro, in Manaus, has shown several ancient rock engravings, which are reappearing as the water decreases. Experts estimate that petroglyphs, as these engravings are also called, are between 1,000 and 2,000 years old.

The engravings are shapes of human faces that are on the rocky walls of the archaeological site of Lajes, on the banks of the Negro River. The last time they were visible was in the 2010 drought. Another rocky block of these engravings is still underwater, but it should appear in the next few days, if the Negro River continues to go down.

Rock engravings on rocks on the edge of the pedral, at the same level as the Rio Negro, appeared last week. Credit: Valter Calheiros.

In addition to these engravings, images of animals and representations of the waters are also seen at the top of the stone, as well as cuts in the rocks possibly as a result of lytic workshops - meaning that the tools for the engravings were made right there.

The engravings are located on extensive walls and under water, which makes their studies complex. According to experts, it cannot be said how the engravings were made, and whether it was at a time of great drought or whether the river, more than a thousand years ago, had a lower level than the current one.

One of the inscriptions on the stones that reappeared with the drought at the archaeological site of Lajes. Credit: Alberto César Araújo/Royal Amazon.

The archaeological site of Lajes covers an area that includes black earth slopes, ceramic fragments and funerary urns, in addition to engravings. However, much of this has disappeared due to human actions and works without supervision.

"These things (the engravings) only appear from time to time. There are two chances. Either they were made in a time of great drought or there were some episodes of drought in the past. But the current droughts happen in a context of climate change, accompanied by the impacts of human actions," says archaeologist Eduardo Goes Neves.

Image on the left: Rio Negro full in the Tumbira community (Credit: Lucas Bonny / Tadeu Rocha) and image on the right: Rio Negro in the same community but during this year's drought (Credit: Disclosure/FAS).

Also according to Neves, the archaeological site of Lajes is a "super important" heritage, but little studied. To make matters worse, the place is impacted and threatened by enterprises, such as the Porto da Lajes project, in addition to graffiti, since people have free access to fishing and resort, and end up scratching the rocks with their names and leaving remains of food on the ground.

"We found these engravings again, but this time with a lot of air pollution, with this smoke that bothers Manaus so much. Around the farm, we see this large amount of garbage. This place needs to be better taken care of, to have the support of Iphan, the institutions. We could have a large field of research to better understand the history of Manaus," says environmental activist and educator Valter Calheiros.