Transport of black carbon-rich smoke from Africa to the Amazon

When forests burn those fires produce a lot of smoke. And that smoke usually contains soot, also called “black carbon”. Black carbon particles are aerosols that absorb radiation and as such can warm the Earth’s atmosphere and climate. But we still have much to learn about aerosols, their properties, and distribution in the atmosphere. One of those things is the question of how black carbon emitted from biomass burning in Africa (i.e. forests, grasslands, savannas etc.) is transported across the Atlantic and into the Amazon basin, and what role it plays there. Bruna Holanda and her co-authors tackled this by combining data from the northeastern Amazon collected with the HALO research aircraft during the ACRIDICON-CHUVA campaign in September 2014, with long-term data from ATTO.

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When do fungi release their spores?

Fungal spore emissions are an important contributor to biogenic aerosols, but we have yet to understand under what conditions fungi release their spores. Nina Löbs and co-authors developed a new technique to measure emissions from single organisms and tested this out at ATTO and with controlled lab experiments. They published their results in the Open Access Journal Atmospheric Measurement Techniques.

large tropical fungi
Fungi of the species Rigidoporus microporus, on which they studied fungal spore emissions. © Sebastian Brill / MPI-C

Aerosols play an important role in various atmospheric processes, and in particular in cloud formation. Therefore it is important to know how they are produced.

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Atmospheric conditions during convective storms over the tropical rainforest

Convective storms often occur the tropics and have the potential to disturb the lower part of the atmosphere. They might even improve the venting of trace gases out of the forest canopy into the atmosphere above. To better understand these processes, Maurício Oliveira and co-authors used the infrastructure at ATTO to study storm outflows during nighttime. They published the results in a new paper in the Open Access Journal Atmospheric Chemistry and Physics.

Why does it rain so frequently in the tropics? The reason is a mixture of many factors, but most importantly it’s very warm and very humid most of the time.

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New publication: Droughts affect leaf flushing in the Amazon

Winter is coming. In the northern hemisphere that is. In these regions, trees are shedding their leaves this time of year, preceded by those beautiful fall colors. Tropical forests like the Amazon do not have such pronounced seasons and are evergreen. Yet they still shed leaves and flush new ones fairly regularly about once a year. What drives the seasonality of leaf flushing we still do not fully understand. But we do now know that this is a really important process because it influences the photosynthetic capacity of the forest. Simply speaking, young leaves are more effective than old ones in performing photosynthesis and sequestering carbon.

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Highly Oxygenated Molecules in the Amazon, Beijing and elsewhere

Air pollution is created by enhanced concentrations of particles in the air. Some of these particles are so large that you can easily see them, such as dust or sand. However many are much smaller so that they can’t be seen with the naked eye. This fine particulate matter (PM2.5) is often more dangerous because smaller particles can penetrate deeper into the lung. In addition, these particles play an important role in our climate system. In the atmosphere, for example, they absorb and reflect light, and act as condensation nuclei for clouds. Thus PM2.5 plays a key role for public health and for climate change.

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