Diurnal variation of the effective height of the aerosol layer according to results of inversion of spectral extinction of light in the near-surface layer and in the atmospheric column in Tomsk

ABSTRACTThe diffusion of Sb and B markers has been studied in vacancy supersaturations produced by MeV Si implantation in float zone (FZ) silicon and bonded etch-back silicon-on-insulator (BESOI) substrates. MeV Si implantation produces a vacancy supersaturated near-surface region and an interstitial-rich region at the projected ion range. Transient enhanced diffusion (TED) of Sb in the near surface layer was observed as a result of a 2 MeV Si+, 1×1016/cm2, implant. A 4× larger TED of Sb was observed in BESOI than in FZ silicon, demonstrating that the vacancy supersaturation persists longer in BESOI than in FZ. B markers in samples with MeV Si implant showed a factor of 10× smaller diffusion relative to markers without the MeV Si+ implant. This data demonstrates that a 2 MeV Si+ implant injects vacancies into the near surface region.

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Observations of a thin near surface layer in an estuarine environment: An exceptional bloom of the dinoflagellate Akashiwo sanguinea in the Lee estuary (Lough Mahon), Co. Cork, in September 2010

Deep Sea Research Part II Topical Studies in Oceanography ◽

10.1016/j.dsr2.2012.12.008 ◽

2014 ◽

Vol 101 ◽

pp. 244-248 ◽

Cited By ~ 12

Author(s):

Shane O'Boyle ◽

Georgina McDermott

Keyword(s):

Surface Layer ◽

Estuarine Environment ◽

Near Surface ◽

Akashiwo Sanguinea

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Physical properties and spatial distribution of the sea ice surface layer (SSL/snow) during the autumn phase of the MOSAiC expedition

10.5194/egusphere-egu21-1467 ◽

2021 ◽

Author(s):

Ruzica Dadic ◽

Martin Schneebeli ◽

Henna-Reeta Hannula ◽

Amy Macfarlane ◽

Roberta Pirazzini

Keyword(s):

Surface Layer ◽

Spatial Distribution ◽

Sea Ice ◽

Physical Properties ◽

Surface Scattering ◽

Climate Feedback ◽

Energy Fluxes ◽

Scattering Layer ◽

Near Surface ◽

Ice Surface

<p>Snow cover dominates the thermal and optical properties of sea ice and the energy fluxes between the ocean and the atmosphere, yet data on the physical properties of snow and its effects on sea ice are limited. This lack of data leads to two significant problems: 1) significant biases in model representations of the sea ice cover and the processes that drive it, and 2) large uncertainties in how sea ice influences the global energy budget and the coupling of climate feedback. The &#160;MOSAiC research initiative enabled the most extensive data collection of snow and surface scattering layer (SSL) properties over sea ice to date. During leg 5 of the MOSAiC expedition, we collected multi-scale (microscale to 100-m scale) measurements of the surface layer (snow/SSL) over first year ice (FYI) and MYI on a daily basis. The ultimate goal of our measurements is to determine the spatial distribution of physical properties of the surface layer. During leg 5 of the MOSAiC expedition, that surface layer changed from the &#160;surface scattering layer (SSL), &#160; characteristic for the melt season, to an early autumn snow pack. Here, &#160;we will present data showing both a) the physical properties and the spatial distribution of the SSL during the late melt season and b) the transition of the sea ice surface from the SSL to the fresh autumn snowpack. The structural properties of this transition period are poorly documented, and this season is critical &#160;for the initialization of sea ice and snow models. Furthermore, these data are crucial to interpret simultaneous observations of surface energy fluxes, surface optical and remote sensing data (microwave signals in particular), near-surface biochemical activity, and to understand the sea ice &#160;processes that occur as the sea ice transitions from melting to freezing.</p>

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Deepening of domains at e-beam writing on the -Z surface of lithium niobate

Journal of Physics D Applied Physics ◽

10.1088/1361-6463/ac44c1 ◽

2021 ◽

Author(s):

Lyudmila Kokhanchik ◽

Evgenii Emelin ◽

Vadim Vladimirovch Sirotkin ◽

Alexander Svintsov

Keyword(s):

Surface Layer ◽

Electron Beam ◽

Lithium Niobate ◽

Electric Field ◽

Domain Walls ◽

Normal Component ◽

Beam Current ◽

Near Surface ◽

Domain Structures ◽

Sign Inversion

Abstract The focus of the study was to investigate the peculiarities of the domains created by electron beam (e-beam) in a surface layer of congruent lithium niobate, which comparable to a depth of electron beam charge penetration. Direct e-beam writing (DEBW) of different domain structures with a scanning electron microscope was performed on the polar -Z cut. Accelerating voltage 15 kV and e-beam current 100 pA were applied. Different patterns of local irradiated squares were used to create domain structures and single domains. No domain contrast was observed by the PFM technique. Based on chemical etching, it was found that the vertices of the domains created do not reach the surface level. The average deepening of the domain vertices was several hundred nanometers and varied depending on the irradiation dose and the location of the irradiated areas (squares) relative to each other. Computer simulation was applied to analyze the spatial distribution of the electric field in the various irradiated patterns. The deepening was explained by the fact that in the near-surface layer there is a sign inversion of the normal component of the electric field strength vector, which controls the domain formation during DEBW. Thus, with the help of e-beam, domains were created completely located in the bulk, in contrast to the domains that are nucleated on the surface of the -Z cut during the polarization inversion with AFM tip. The detected deepening of e-beam domains suggests the possibility of creating the “head-to-head” domain walls in the near-surface layer lithium niobate by DEBW.

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Transport Characteristics of the Near-Surface Layer of the Nucleus of Comet 67P/Churyumov–Gerasimenko

Solar System Research ◽

10.1134/s0038094621020040 ◽

2021 ◽

Vol 55 (2) ◽

pp. 106-123

Author(s):

V. Reshetnyk ◽

Yu. Skorov ◽

M. Vasyuta ◽

M. Bentley ◽

L. Rezac ◽

...

Keyword(s):

Surface Layer ◽

Near Surface ◽

Comet 67P

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Dome effect of black carbon and its key influencing factors: A one-dimensional modelling study

10.5194/acp-2017-967 ◽

2017 ◽

Author(s):

Zilin Wang ◽

Xin Huang ◽

Aijun Ding

Keyword(s):

Boundary Layer ◽

Air Pollution ◽

Black Carbon ◽

Rural Areas ◽

Land Surface ◽

Critical Role ◽

Aerosol Layer ◽

Near Surface ◽

Haze Pollution ◽

The Impact

Abstract. Black carbon (BC) has been identified to play a critical role in aerosol-planet boundary layer (PBL) interaction and further deterioration of near-surface air pollution in megacities, which has been named as its dome effect. However, the impacts of key factors that influence this effect, such as the vertical distribution and aging processes of BC, and also the underlying land surface, have not been quantitatively explored yet. Here, based on available in-situ measurements of meteorology and atmospheric aerosols together with the meteorology-chemistry online coupled model, WRF-Chem, we conduct a set of parallel simulations to quantify the roles of these factors in influencing the BC's dome effect and surface haze pollution, and discuss the main implications of the results to air pollution mitigation in China. We found that the impact of BC on PBL is very sensitive to the altitude of aerosol layer. The upper level BC, especially those near the capping inversion, is more essential in suppressing the PBL height and weakening the turbulence mixing. The dome effect of BC tends to be significantly intensified as BC aerosol mixed with scattering aerosols during winter haze events, resulting in a decrease of PBL height by more than 25 %. In addition, the dome effect is more substantial (up to 15 %) in rural areas than that in the urban areas with the same BC loading, indicating an unexpected regional impact of such kind of effect to air quality in countryside. This study suggests that China's regional air pollution would greatly benefit from BC emission reductions, especially those from the elevated sources from the chimneys and also the domestic combustions in rural areas, through weakening the aerosol-boundary layer interactions that triggered by BC.

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