Hemispheric contrasts in ice formation in stratiform mixed-phase clouds: Disentangling the role of aerosol and dynamics with ground-based remote sensing

Radenz, Martin; Bühl, Johannes; Seifert, Patric; Baars, Holger; Engelmann, Ronny; Barja, Boris; Mamouri, Rodanthi; Zamorano, Félix; Ansmann, Albert

doi:10.5194/acp-2021-360

Cited by 13 publications

(17 citation statements)

References 80 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Generally, indeed, a well-mixed boundary layer also was seen during most of the observation periods, as the particle backscatter coefficients were often constant for altitudes between 250 m and 1.2 km (as also indicated in Fig. 3 of Radenz et al, 2021).…”

Section: Relationship Between In-situ Measured N >500nm and Lidar Datasupporting

confidence: 53%

“…With exception of sample 11, no extended periods of boundary layer top heights below 800 m were observed. Also, mineral dust in the free troposphere was not observed during the sampling period (Radenz et al, 2021). This and the above discussed origin of the backward trajectories makes it unlikely that observed high concentrations of INP originated from mineral dust particles.…”

mentioning

confidence: 79%

“…The spatiotemporal distribution of aerosol particles (Yu et al, 2010;Mehta et al, 2016) and clouds (Wylie et al, 2005) varies greatly across the Northern and Southern Hemisphere and current conceptual models of cloud and precipitation formation fail to accurately reproduce the conditions in the mid and higher latitudes of the Southern Hemisphere. Previous studies found larger ice number concentrations in mid-level stratiform mixed-phase clouds over the Northern Hemisphere than over the Southern Hemisphere (Kanitz et al, 2011;Zhang et al, 2018;Alexander and Protat, 2018;Radenz et al, 2021). Therefore, it is crucial to examine the population and sources of ice-nucleating particles in the Southern Hemisphere.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Significant continental source of ice-nucleating particles at the tip of Chile’s southernmost Patagonia region

Gong

Radenz

Wex

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Abstract. The sources and abundance of ice-nucleating particles (INPs) that initiate cloud ice formation remain understudied, especially in the Southern Hemisphere. In this study, we present INP measurement taken close to Punta Arenas, Chile, at the southernmost tip of South America from May 2019 to March 2020, during the Dynamics, Aerosol, Clouds, and Precipitation in the Pristine Environment of the Southern Ocean (DACAPO-PESO) campaign. The highest ice nucleation temperature was observed at -3 °C, and from this temperature down to ~ -10 °C, a sharp increase of INP number concentration (NINP) was observed. Roughly 90 % and 80 % of INPs are proteinaceous-based biogenic particles at > -10 and -15 °C, respectively. NINP at Punta Arenas is much higher than that in the Southern Ocean, but comparable with agricultural area in Argentina and forestry environment in the US. Ice active surface site density (ns) is much higher than that for marine aerosol in the Southern Ocean, but comparable to English fertile soil dust. Parameterization based on particle number concentration in the size range larger than 500 nm (N>500nm) from the global average (DeMott et al., 2010) overestimate the measured INP, but the parameterization representing biological particles from a forestry environment (Tobo et al., 2013) yields NINP comparable to this study. No clear seasonal variation of NINP was observed. High precipitation is one of the most important meteorological parameters to enhance the NINP both in cold and warm seasons. A comparison of data from in-situ and lidar measurements showed good agreement for concentrations of large aerosol particles (> 500 nm) when assuming continental conditions for retrieval of the lidar data, suggesting that these particles were well mixed within the planetary boundary layer. This corroborates a continental origin of these particles, consistent with the results from our INP source analysis. Overall, we suggest that high NINP of biogenic INPs originated from terrestrial sources and were added to the marine air masses during the overflow of a maximum of roughly 150 km of land before arriving at the measurement station.

show abstract

Section: Relationship Between In-situ Measured N >500nm and Lidar Datasupporting

confidence: 53%

mentioning

confidence: 79%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Significant continental source of ice-nucleating particles at the tip of Chile’s southernmost Patagonia region

Gong

Radenz

Wex

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…The lidar observations at Punta Arenas (53.14 • S, 70.89 • W; 9 m above sea level), Chile, were conducted in the framework of the long-term campaign Dynamics, Aerosol, Cloud And Precipitation Observations in the Pristine Environment of the Southern Ocean(DACAPO-PESO; https://dacapo.tropos.de, last access: 5 October 2021). The main goal of DACAPO-PESO is the investigation of aerosol-cloud interaction processes in rather pristine, unpolluted marine conditions (Radenz et al, 2021). The Polly instrument (POrtabLle Lidar sYstem; Engelmann et al, 2016) was operated at the University of Magallanes (UMAG) at Punta Arenas from November 2018 until October 2021.…”

Section: Ground-based Lidar Remote Sensingmentioning

confidence: 99%

Important role of stratospheric injection height for the distribution and radiative forcing of smoke aerosol from the 2019–2020 Australian wildfires

et al. 2022

Self Cite

View full text Add to dashboard Cite

Abstract. More than 1 Tg smoke aerosol was emitted into the atmosphere by the exceptional 2019–2020 southeastern Australian wildfires. Triggered by the extreme fire heat, several deep pyroconvective events carried the smoke directly into the stratosphere. Once there, smoke aerosol remained airborne considerably longer than in lower atmospheric layers. The thick plumes traveled eastward, thereby being distributed across the high and mid-latitudes in the Southern Hemisphere, enhancing the atmospheric opacity. Due to the increased atmospheric lifetime of the smoke plume, its radiative effect increased compared to smoke that remains in lower altitudes. Global models describing aerosol-climate impacts lack adequate descriptions of the emission height of aerosols from intense wildfires. Here, we demonstrate, by a combination of aerosol-climate modeling and lidar observations, the importance of the representation of those high-altitude fire smoke layers for estimating the atmospheric energy budget. Through observation-based input into the simulations, the Australian wildfire emissions by pyroconvection are explicitly prescribed to the lower stratosphere in different scenarios. Based on our simulations, the 2019–2020 Australian fires caused a significant top-of-atmosphere (TOA) hemispheric instantaneous direct radiative forcing signal that reached a magnitude comparable to the radiative forcing induced by anthropogenic absorbing aerosol. Up to +0.50 W m−2 instantaneous direct radiative forcing was modeled at TOA, averaged for the Southern Hemisphere (+0.25 W m−2 globally) from January to March 2020 under all-sky conditions. At the surface, on the other hand, an instantaneous solar radiative forcing of up to −0.81 W m−2 was found for clear-sky conditions, with the respective estimates depending on the model configuration and subject to the model uncertainties in the smoke optical properties. Since extreme wildfires are expected to occur more frequently in the rapidly changing climate, our findings suggest that high-altitude wildfire plumes must be adequately considered in climate projections in order to obtain reasonable estimates of atmospheric energy budget changes.

show abstract

“…They, therefore, mark a natural laboratory for studies of heterogeneous glaciation in environments where efficient INPs are present. Polarization lidar measurements can be used to investigate the effect of mineral dust (Ansmann et al, 2005(Ansmann et al, , 2008(Ansmann et al, , 2009(Ansmann et al, , 2019, volcanic ash (Seifert et al, 2011), or other aerosol particle types (Kanitz et al, 2011;Seifert et al, 2015;Cheng and Yi, 2020;Radenz et al, 2021;Yi et al, 2021) acting as INPs in the heterogeneous glaciation of altocumulus clouds.…”

Section: Introductionmentioning

confidence: 99%

Locations for the best lidar view of mid-level and high clouds

Tesche

Noël

2022

Atmos. Meas. Tech.

View full text Add to dashboard Cite

Abstract. Mid-level altocumulus clouds (Ac) and high cirrus clouds (Ci) can be considered natural laboratories for studying cloud glaciation in the atmosphere. While their altitude makes them difficult to access with in situ instruments, they can be conveniently observed from the ground with active remote-sensing instruments such as lidar and radar. However, active remote sensing of Ac and Ci at visible wavelengths with lidar requires a clear line of sight between the instrument and the target cloud. It is therefore advisable to carefully assess potential locations for deploying ground-based lidar instruments in field experiments or for long-term observations that are focused on mid- or high-level clouds. Here, observations of clouds with two spaceborne lidars are used to assess where ground-based lidar measurements of mid- and high-level clouds are least affected by the light-attenuating effect of low-level clouds. It is found that cirrus can be best observed in the tropics, the Tibetan Plateau, the western part of North America, the Atacama region, the southern tip of South America, Greenland, Antarctica, and parts of western Europe. For the observation of altocumulus, a ground-based lidar is best placed at Greenland, Antarctica, the western flank of the Andes and Rocky Mountains, the Amazon, central Asia, Siberia, western Australia, or the southern half of Africa.

show abstract

Hemispheric contrasts in ice formation in stratiform mixed-phase clouds: Disentangling the role of aerosol and dynamics with ground-based remote sensing

Cited by 13 publications

References 80 publications

Significant continental source of ice-nucleating particles at the tip of Chile’s southernmost Patagonia region

Significant continental source of ice-nucleating particles at the tip of Chile’s southernmost Patagonia region

Important role of stratospheric injection height for the distribution and radiative forcing of smoke aerosol from the 2019–2020 Australian wildfires

Locations for the best lidar view of mid-level and high clouds

Contact Info

Product

Resources

About