Climate change and biodiversity in Brazil: What we know, what we don’t, and Paris Agreement’s risk reduction potential

Over recent decades, Brazil has amassed a wealth of knowledge regarding the potential effects of climate change on its biodiversity. Studies have predicted mostly negative impacts and some positive ones, and it is time to synthesize this information. We did a systematic review of the literature and quantitative analysis, gathering 20,582 risk projections from 131 papers. We then estimated the effect size of the projected risks. We found that climate change impacts on biodiversity vary spatially. The Pantanal wetlands are predicted to experience the most significant negative impacts, followed by the Amazon and the Atlantic Forest, while the Pampa grasslands are expected to see lower impacts. Our analysis also reveals biases and knowledge gaps. For example, the shortage of studies on marine environments precluded their inclusion in the analysis, and there was a strong bias towards the Amazon and the Atlantic Forest, with a shortage of studies on the Pantanal and the Pampa. Moreover, there was a taxonomic bias towards plants and terrestrial vertebrates, which comprised >90% of the data. Finally, while adherence to the Paris Agreement is unlikely to eliminate climate change impacts on biodiversity, our analysis predicts that it could reduce these impacts by 20% and halve the number of species at risk of extinction from climate change in Brazil.