Publications by authors named "Einar Karu"

Article Synopsis
  • Wildfires release a significant amount of black carbon (BC) particles into the atmosphere, which can reach the lowermost stratosphere (LMS) and contribute to climate change through strong radiative forcing.
  • During a 14-month study on a passenger flight between Europe and North America, researchers detected frequent biomass burning (BB) plumes that affected 16 out of 160 flight hours in the LMS, with BC mass concentrations remarkably higher than normal background levels.
  • The study also noted that BC particles in these plumes were larger and had thicker coatings compared to background particles, indicating that wildfires can cause substantial local heating in the LMS and impact regional climate radiative forcing.
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Ambient desorption/ionization mass spectrometry (MS) has gained growing interest during the last decade due to its high analytical performance and yet simplicity. Here, one of the recently developed ambient desorption/ionization MS sources, the flowing atmospheric-pressure afterglow (FAPA) source, was investigated in detail regarding background ions and typical ionization patterns in the positive as well as the negative ion mode for a variety of compound classes, comprising alkanes, alcohols, aldehydes, ketones, carboxylic acids, organic peroxides and alkaloids. A broad range of signals for adducts and losses was found, besides the usually emphasized detection of quasimolecular ions, i.

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Organic compounds contribute to a major fraction of atmospheric aerosols and have significant impacts on climate and human health. However, because of their chemical complexity, their measurement remains a major challenge for analytical instrumentation. Here we present the development and characterization of a new soft ionization technique that allows mass spectrometric real-time detection of organic compounds in aerosols.

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