Is Climate Change Killing Pantanal, The World’s Largest Tropical Wetlands?
More than 70,000 square kilometres of marsh and forest land have burnt in the Pantanal in the last three years. This equals about 4 million football fields. The Pantanal Wetlands are located in the heart of South America and are the world’s largest tropical wetlands. Home to a wealth of biodiversity, they stretch from Brazil into Paraguay and Bolivia. Unlike the Amazon Rainforest, vegetation in the Pantanal has evolved to coexist with fire — many plant species there require the heat from fires to germinate. Often caused by lightning strikes, those natural fires spring up at the end of the dry season, but the surrounding floodplains prevent them from spreading. What’s different now is the drought, contributing further to the unusually dry conditions and exacerbating the fire risk. More than 580 species of bird, 271 of fish, 174 mammals, 131 reptiles and 57 amphibians thrive in the region’s flooded areas, grasslands, lakes and forests. Unceasing fires have killed many species or left them without homes to migrate to. The number of fires in the region has been drastically increasing with every passing year - In 2020 there were 3506 fires from January 1st to July 22, a 192% increase from 2019. In 2019-20, the region suffered the worst drought in 50 years. The Parana river which runs through Brazil, Paraguay and Argentina is undergoing its worst drought in 80 years right now, which scientists have attributed to climate change. The Pantanal wetlands supply water to the Paraguay river which in turn supplies to the Parana river that impacts an ecosystem comprising 40 million people including fishing communities, farmers and a major export hub in both Brazil and Argentina. The droughts have not only affected biodiversity but also local communities and their freshwater supply. The drought has been caused because of a phenomenon known as ‘atmospheric blocking’. An odd ‘high-pressure area’ prevented the formation of rain clouds resulting in high temperatures and low humidity. Part of the rain that falls on the Pantanal is brought by winds blowing from the North Atlantic to the Amazon. The humidity coming down from the Amazon and cold fronts coming up from the South were prevented by this high-pressure bubble. So, masses of warmer and drier air have contributed to the scarcity of rain during the summer. Burning of vegetation to clear land for cattle ranching also contributed to the spread of wildfires across the region. José Marengo, a researcher at Natural Disaster Surveillance and Early Warning Center (CEMADEN) said that “Fires caused by warmer thick air and lack of rain in the Pantanal and burning of vegetation on the other hand has resulted in an environmental disaster.” The recent drought has been different from the ones in the 1950s and 1960s when the planet was cooler. Right now, these natural droughts are suffering the effects of unstable climate systems, and the effects are worse because the dense population is now more vulnerable to the impact of droughts than ever before.
Source: Down To Earth