Publications by authors named "Peter van Velthoven"
Article Synopsis
- The study compares aerosol samples collected from the IAGOS-CARIBIC aircraft with aerosol backscattering data from the CALIOP lidar on the CALIPSO satellite to understand aerosol composition in the lowermost stratosphere.
- Concentrations of key stratospheric aerosol components, mainly sulphur and carbon, were analyzed post-flight, complementing existing black carbon data to assess overall aerosol backscattering.
- The findings reveal discrepancies between the two measurement methods, highlighting that the best agreement occurs during volcanic activity or when aerosol levels are elevated, particularly in winter and spring above the tropopause.
The chlorine radical is a potent atmospheric oxidant, capable of perturbing tropospheric oxidative cycles normally controlled by the hydroxyl radical. Significantly faster reaction rates allow chlorine radicals to expedite oxidation of hydrocarbons, including methane, and in polluted environments, to enhance ozone production. Here we present evidence, from the CARIBIC airborne dataset, for extensive chlorine radical chemistry associated with Asian pollution outflow, from airborne observations made over the Malaysian Peninsula in winter.
View Article and Find Full Text PDFDespite their potential to slow global warming, until recently, the radiative forcing associated with volcanic aerosols in the lowermost stratosphere (LMS) had not been considered. Here we study volcanic aerosol changes in the stratosphere using lidar measurements from the NASA CALIPSO satellite and aircraft measurements from the IAGOS-CARIBIC observatory. Between 2008 and 2012 volcanism frequently affected the Northern Hemisphere stratosphere aerosol loadings, whereas the Southern Hemisphere generally had loadings close to background conditions.
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