Before we leave to the field station and you won't read anything new on this site for a few days , I briefly want to explain the motivation for such a project:
It is all about climate change and understanding climate, as well as understanding cloud formation and precipitation, and the connection between these.
A lot of research has been done in other places of the world, especially in the
What are aerosol particles: Aerosol particles are tiny droplets or solid particles in the atmosphere, with diameters in the size range between roughly 10 nanometers (0.00000001 m) and 10 µm (0.00001 m). Why are they so important? Besides their health effect (in polluted areas) and their radiative effect (the so-called "direct aerosol effect" on climate), they are a prerequisite for cloud formation. Without aerosol particles, no cloud would form, because water vapor needs a very high supersaturation to condense in pure air. The condensation on a pre-existing aerosol particle is highly preferred. These aerosol particles are then called cloud condensation nuclei (CCN). A special subset are the ice-forming aerosol particles, the ice nuclei (IN). Ice in the Amazonian rain forest? Yes, if you go up in the atmosphere, temperature decreases, and in an altitude of about 4 km you reach 0°C, and higher above, the temperature can reach values of down -70°C in the tropics, at altitudes of about 16 km. Convective cumulus clouds can transport the air and the aerosol particles from ground level to high altitudes in a few hours, thereby causing the heavy thunderstorms associated with heavy rainfall.
The ability of an aerosol particle to act as a CCN or as IN depends on parameters like size and chemical composition. Our goal is to measure these properties here in the pristine rain forest, in order to understand the mechanisms of cloud formation over the rain forest, and possibly this allows other scientists to extrapolate these findings to higher temperatures that are expected when climate change continues (and it will).
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