“The IPCC (Intergovernmental Panel on Climate Change) models project future climate up to 2100 considering various socioeconomic trajectories, which reflect levels of warming…”
José Antonio Marengo Orsini is the general coordinator of Research and Development at the National Center for Monitoring and Early Warning of Natural Disasters – Cemaden.
Marengo has a degree in physics and meteorology from the La Molina National Agrarian University in Peru, and a Ph.D. from the University of Wisconsin.
José Marengo, general R&D coordinator at Cemaden
AgriBrasilis – How far can the climate crisis go?
José Marengo – If global warming continues to intensify, we will experience more intense and frequent extremes: droughts, heavy rains that can cause disasters, heat waves, and more intense hurricanes. All of this can affect human life and the ecosystems and services they provide.
The main people affected would be the most vulnerable populations around the world, which are the ones that contribute the least to greenhouse gas emissions.
AgriBrasilis – What do the IPCC’s models and other panels’ models show for the near future?
José Marengo – The IPCC (Intergovernmental Panel on Climate Change) models project future climate up to 2100 considering various socioeconomic trajectories, which reflect levels of warming. All estimates project an increase in temperatures around the world and regional changes in rainfall patterns.
In South America, more abundant and intense rainfall is projected in the southeast of South America and in the eastern Amazon and Northeast. In Central America, rainfall reductions are estimated up to 2100.
The changes will be more intense if global warming reaches 4º Celsius, a scenario in which adaptation will be difficult. If global warming does not exceed 1.5º Celsius, the changes will be less intense and adaptation could be feasible.
“The cause of the fires is human, intentional or unintentional, as is the case in Brazil in general, where more than 95% of fires are human-caused”
AgriBrasilis – Climate extremes are becoming increasingly frequent. How will this affect agriculture?
José Marengo – Yes, and this process is already happening in the present, as a consequence of global warming.
Extreme droughts and heavy rains are occurring more frequently. There is an increased risk of droughts and water deficits for agriculture, droughts and heat waves, which generate water shortages that affect crops. Another factor is extreme rains, which cause flooding, as happened in the State of Rio Grande do Sul, affecting rice crops.
Deforestation in the Amazon and climate change can affect the rain cycle and thus generate drought problems in the agribusiness region, in the States of Mato Grosso do Sul and Mato Grosso, for example.
AgriBrasilis – Could the floods in the South region happen again?
José Marengo – Yes, and not only in the South, but in other regions of Brazil, and could affect urban and rural areas.
The event that happened in May of 2024 has already shown that agriculture and the population of the State of Rio Grande do Sul are not resilient to the current climate extremes, much less to a climate with more extremes, which is what is estimated for the future.
AgriBrasilis – Are the fires in the sugarcane fields in São Paulo the result of climate change?
José Marengo – The cause of the fires is human, intentional or unintentional, as is the case in Brazil in general, where more than 95% of fires are human-caused.
What favors the presence of fires is the presence of a drier and hotter climate, as is the case now, where the west of the State of São Paulo is under the influence of droughts and heat waves.
Although the causes of droughts and heat waves are the result of meteorological events, there are already attribution studies that show that these phenomena may be more frequent due to climate changes of human origin.
AgriBrasilis – Which areas in Brazil are the most vulnerable and why?
José Marengo – It depends. In the case of social vulnerability, we can mention the semiarid region and indigenous peoples and traditional communities. In terms of biodiversity: the Amazon, Pantanal and Cerrado biomes. Regarding water security: we would have to say the Center-West and Southeast.
In the South, there are vulnerabilities related to extreme events and disasters, such as landslides, floods and inundations. Ultimately, Brazil as a whole is vulnerable to climate extremes and suffers from climate change.
AgriBrasilis – Is Brazil really treating climate change as a priority agenda?
José Marengo – In the current government, I would say yes. The issue of climate change is dealt with at the interministerial level, but the actions are concentrated in the Ministry of the Environment and Climate Change – MMA and the Ministry of Science, Technology and Innovation – MCTI, which together are developing the CLIMA Adaptation and Mitigation Plans.
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