Aerosol measurements with a shipborne Sun–sky–lunar photometer and collocated multiwavelength Raman polarization lidar over the Atlantic Ocean

Abstract

Abstract. A shipborne Sun–sky–lunar photometer of type CE318-T was tested during two trans-Atlantic cruises aboard the German research vessel Polarstern from 54∘ N to 54∘ S in May/June and December 2018. The continuous observations of the motion-stabilized shipborne CE318-T enabled the first-time observation of a full diurnal cycle of aerosol optical depth (AOD) and column-mean Ångström coefficient of a mixed dust–smoke episode. The latitudinal distribution of the AOD from the shipborne CE318-T, Raman lidar and MICROTOPS II shows the same trend with highest values in the dust belt from 0 to 20∘ N and overall low values in the Southern Hemisphere. The linear-regression coefficients of determination between MICROTOPS II and the CE318-T were 0.988, 0.987, 0.994 and 0.994 for AODs at 380, 440, 500 and 870 nm and 0.896 for the Ångström exponent at 440–870 nm. The root-mean-squared differences of AOD at 380, 440, 500 and 870 nm were 0.015, 0.013, 0.010 and 0.009, respectively.

Automated time-height-resolved airmass source attribution for profiling remote sensing applications

“…At heights between 2 and 4 km, barren areas from Africa are the main source, but a considerable fraction is also attributed to African grass/cropland and Savanna. This finding is supporting the observations presented by Yin et al (2019) who already discuss that there was likely a small non-dust fraction in the upper layer, as the particle depolarization ratio profile was not constant at all heights. A potential reason for the observed discrepancy of the observations from pure-dust conditions could be the presence of wildfire smoke stemming from the crop/grassland and savanna.…”

“…Arenas (Chile) to Bremerhaven (Germany). A detailed description of the event and optical properties of the observed aerosol were already reported by Yin et al (2019). in detail the time and height period of the observation which is marked by a horizontal orange bar in Fig.…”

Application of the shipborne remote sensing supersite OCEANET for profiling of Arctic aerosols and clouds during <i>Polarstern</i> cruise PS106

“…The OCEANET-Atmosphere observatory was already frequently operated aboard Polarstern (Kanitz et al, 2013b;Bohlmann et al, 2018;Yin et al, 2019) -yet, so far only for the transects from the Northern Hemisphere to the Southern Hemisphere (or vice versa) but never in the Polar regions. Its container is by default equipped with the multiwavelength polarization Raman lidar Polly XT _OCEANET (hereafter referred to as Polly XT ), in order to provide continuous profiles of cloud and aerosol properties (Engelmann et al, 2016).…”

“…In contrast to Nomokonova et al (2019), which provided a statistical analysis of the cloud occurrence over Ny Ålesund, Svalbard, for the period between June 2016 and July 2017, we found a higher frequency of single-layer mixedphase clouds at the expense of cloud-free and single-layer liquid clouds when comparing the period of PS106. This may be due to a difference in turbulence as well as a change in the cloud microphysics at locations surrounded by sea ice or open ocean (Young et al, 2016).…”

Evaluation of satellite-based aerosol datasets and the CAMS reanalysis over the ocean utilizing shipborne reference observations

“…Therefore, knowledge about the spectrally resolved optical properties of different aerosol types is essential. Over the ocean, sea spray (Bellouin et al, 2005;Loeb and Manalo-Smith, 2005;Yu et al, 2006;Myhre et al, 2007) and desert dust (e.g. Tegen, 2003;Christopher and Jones, 2007;Nabat et al, 2015) are the major contributors to the direct radiative effect of aerosol.…”