Ubiquity of biological ice nucleators in snowfall
Aerosols play an integral role in climate by directly scattering or absorbing solar radiation, and indirectly these particles serve as condensation and ice nuclei in clouds. Ice formation in tropospheric clouds is required for snow and most rainfall. At temperatures> –40°C, ice formation is not s...
| Main Authors: | , , , , |
|---|---|
| Other Authors: | |
| Format: | Text |
| Language: | English |
| Subjects: | |
| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.395.4918 http://rifters.com/real/articles/Science_Christner_et_al_2008.pdf |
| Summary: | Aerosols play an integral role in climate by directly scattering or absorbing solar radiation, and indirectly these particles serve as condensation and ice nuclei in clouds. Ice formation in tropospheric clouds is required for snow and most rainfall. At temperatures> –40°C, ice formation is not spontaneous, and diverse substrates can act as catalysts of ice nucleation (1). Biological ice nucleators (IN) are the most active IN in nature, and some bacterial plant pathogens can catalyze ice formation at temperatures near –2°C. Although biological particles are important components of aerosols (2), existing technologies are unable to detect IN active at temperatures> –10°C (3), and the impact of biological IN on atmospheric processes remains ambiguous (4). We examined the concentration and nature of IN active at temperatures> –10°C in 19 fresh snowfalls collected at mid- and high-latitude locations from October2005toJune2006(5) and found the lowest cumulative concentration of IN at –9°C in Antarctic snowfall (four IN per liter of snow melt) and highest |
|---|