Ice nucleation efficiency of natural dust samples in the immersion mode ...
A total of 12 natural surface dust samples, which were surface-collected on four continents, most of them in dust source regions, were investigated with respect to their ice nucleation activity. Dust collection sites were distributed across Africa, South America, the Middle East, and Antarctica. Min...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
ETH Zurich
2016
|
| Subjects: | |
| Online Access: | https://dx.doi.org/10.3929/ethz-b-000120332 http://hdl.handle.net/20.500.11850/120332 |
| Summary: | A total of 12 natural surface dust samples, which were surface-collected on four continents, most of them in dust source regions, were investigated with respect to their ice nucleation activity. Dust collection sites were distributed across Africa, South America, the Middle East, and Antarctica. Mineralogical composition has been determined by means of X-ray diffraction. All samples proved to be mixtures of minerals, with major contributions from quartz, calcite, clay minerals, K-feldspars, and (Na, Ca)-feldspars. Reference samples of these minerals were investigated with the same methods as the natural dust samples. Furthermore, Arizona test dust (ATD) was re-evaluated as a benchmark. Immersion freezing of emulsion and bulk samples was investigated by differential scanning calorimetry. For emulsion measurements, water droplets with a size distribution peaking at about 2µm, containing different amounts of dust between 0.5 and 50wt% were cooled until all droplets were frozen. These measurements characterize ... : Atmospheric Chemistry and Physics, 16 (17) ... |
|---|