New type of hand-held corer for meiofaunal sampling and vertical profile investigation: a comparative study

A new hand-held corer for meiofaunal sampling and vertical profile investigation was developed. Its design and use prevents problems connected with core compression caused by the use of a plunger for core extrusion as generally applied in common coring techniques. This represents an advantage when meiofauna vertical profiles are investigated. A comparison between vertical profiles obtained from the newly developed corer and from commonly used corers shows that non-extrusive techniques significantly reduce sediment core compression.

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Vertical profiles of trace elements in a sediment core from the Lambro River (Northern Italy): historical trends and pollutant transport to the Adriatic Sea

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.146766 ◽

2021 ◽

pp. 146766

Author(s):

Laura Marziali ◽

Lucia Valsecchi ◽

Alfredo Schiavon ◽

Domenico Mastroianni ◽

Luigi Viganò

Keyword(s):

Trace Elements ◽

Sediment Core ◽

Adriatic Sea ◽

Pollutant Transport ◽

Northern Italy ◽

Vertical Profiles ◽

Historical Trends

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Comparative study on the hydrodynamics and mixing characteristics of a new-type particle mixer

Powder Technology ◽

10.1016/j.powtec.2018.03.057 ◽

2018 ◽

Vol 332 ◽

pp. 90-105 ◽

Cited By ~ 3

Author(s):

Zhenliang Meng ◽

Mengxi Liu ◽

Junming Xie ◽

Wei Wang ◽

Chunxi Lu

Keyword(s):

Comparative Study ◽

Mixing Characteristics ◽

New Type ◽

Type Particle

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Vertical Characteristics of Reflectivity in Intense Convective Clouds using TRMM PR Data

Environment and Natural Resources Research ◽

10.5539/enrr.v7n2p58 ◽

2017 ◽

Vol 7 (2) ◽

pp. 58 ◽

Cited By ~ 7

Author(s):

Shailendra Kumar

Keyword(s):

Vertical Profile ◽

Regional Differences ◽

Vertical Structure ◽

Convective Cloud ◽

Convective Precipitation ◽

Vertical Profiles ◽

Gangetic Plain ◽

Convective Clouds ◽

Trmm Pr ◽

Precipitation Area

Tropical Rainfall Measuring Mission Precipitation Radar (TRMM-PR) based vertical structure in intense convective precipitation is presented here for Indian and Austral summer monsoon seasons. TRMM 2A23 data is used to identify the convective echoes in PR data. Two types of cloud cells are constructed here, namely intense convective cloud (ICC) and most intense convective cloud (MICC). ICC consists of PR radar beams having Ze>=40 dBZ above 1.5 km in convective precipitation area, whereas MICC, consists of maximum reflectivity at each altitude in convective precipitation area, with at least one radar pixel must be higher than 40 dBZ or more above 1.5 km within the selected areas. We have selected 20 locations across the tropics to see the regional differences in the vertical structure of convective clouds. One of the important findings of the present study is identical behavior in the average vertical profiles in intense convective precipitation in lower troposphere across the different areas. MICCs show the higher regional differences compared to ICCs between 5-12 km altitude. Land dominated areas show higher regional differences and Southeast south America (SESA) has the strongest vertical profile (higher Ze at higher altitude) followed by Indo-Gangetic plain (IGP), Africa, north Latin America whereas weakest vertical profile occurs over Australia. Overall SESA (41%) and IGP (36%) consist higher fraction of deep convective clouds (>10 km), whereas, among the tropical oceanic areas, Western (Eastern) equatorial Indian ocean consists higher fraction of low (high) level of convective clouds. Nearly identical average vertical profiles over the tropical oceanic areas, indicate the similarity in the development of intense convective clouds and useful while considering them in model studies.

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Vertical Profiles of Dioxin-like and Estrogenic Activities Associated with a Sediment Core from Tokyo Bay, Japan

Environmental Science & Technology ◽

10.1021/es001044a ◽

2000 ◽

Vol 34 (17) ◽

pp. 3568-3573 ◽

Cited By ~ 28

Author(s):

Kurunthachalam Kannan ◽

Daniel L. Villeneuve ◽

Nobuyoshi Yamashita ◽

Takashi Imagawa ◽

Shinya Hashimoto ◽

...

Keyword(s):

Sediment Core ◽

Tokyo Bay ◽

Vertical Profiles

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The Design and Application of a New Type of Instrument for Testing the Worn Surface of Casing Wear

STLE/ASME 2008 International Joint Tribology Conference ◽

10.1115/ijtc2008-71258 ◽

2008 ◽

Cited By ~ 1

Author(s):

Jianchun Fan ◽

Qiang Chen ◽

Laibin Zhang ◽

Dong Wen

Keyword(s):

Comparative Study ◽

Surface Reconstruction ◽

Wear Mechanism ◽

3D Surface Reconstruction ◽

3D Surface ◽

Testing Data ◽

New Type ◽

Casing Wear ◽

The Comparative Study ◽

Worn Surface

In this paper, a new kind of instrument used specially for testing the worn surface of casing was introduced, its structure and testing principle was further elaborated. Meanwhile, the testing data were also used for the 3D surface reconstruction of the worn area of casing. The comparative study with SEM pictures could tell that the instrument performed very well and is quite helpful in the observation of worn rejoin of casing; the conclusions drawn from the study could be applied in the research of wear mechanism.

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Comparison of Oceanic Δ14C Data with Those of GEOSECS: Vertical Profiles in 1973 (GEOSECS) and in 1980 at (30° N, 170° E) in the Northwestern Pacific Ocean

Radiocarbon ◽

10.1017/s0033822200043551 ◽

1987 ◽

Vol 29 (1) ◽

pp. 53-56 ◽

Cited By ~ 8

Author(s):

Toshitaka Gamo ◽

Yoshio Horibe ◽

Hiromi Kobayashi

Keyword(s):

Proportional Counter ◽

Vertical Profile ◽

Sea Water ◽

The Other ◽

Northwestern Pacific ◽

Vertical Profiles ◽

Northwestern Pacific Ocean ◽

Systematic Deviation ◽

Gas Proportional Counter ◽

Good Agreement

The vertical profile of radiocarbon at (30° N, 170° E) measured in 1980 was compared with the GEOSECS data measured in 1973. 14C was extracted from 200L of sea water, converted to C2H2, and analyzed with a gas proportional counter. Our profile and that of GEOSECS were in good agreement below 700m depth without systematic deviation of Δ14C values between both measurements. On the other hand, a Δ14C increase was observed above 700m depth, reflecting the transient addition, in 6.6 years, of bomb 14C to the intermediate layer from the atmosphere.

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Dust vertical profile impact on global radiative forcing estimation using a coupled chemical-transport–radiative-transfer model

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-7097-2013 ◽

2013 ◽

Vol 13 (14) ◽

pp. 7097-7114 ◽

Cited By ~ 35

Author(s):

L. Zhang ◽

Q. B. Li ◽

Y. Gu ◽

K. N. Liou ◽

B. Meland

Keyword(s):

Heating Rate ◽

Vertical Profile ◽

Radiative Forcing ◽

Asian Dust ◽

Dust Particles ◽

Radiative Transfer Model ◽

Transfer Model ◽

Vertical Profiles ◽

Dust Source ◽

Source Regions

Abstract. Atmospheric mineral dust particles exert significant direct radiative forcings and are important drivers of climate and climate change. We used the GEOS-Chem global three-dimensional chemical transport model (CTM) coupled with the Fu-Liou-Gu (FLG) radiative transfer model (RTM) to investigate the dust radiative forcing and heating rate based on different vertical profiles for April 2006. We attempt to actually quantify the sensitivities of radiative forcing to dust vertical profiles, especially the discrepancies between using realistic and climatological vertical profiles. In these calculations, dust emissions were constrained by observations of aerosol optical depth (AOD). The coupled calculations utilizing a more realistic dust vertical profile simulated by GEOS-Chem minimize the physical inconsistencies between 3-D CTM aerosol fields and the RTM. The use of GEOS-Chem simulated vertical profile of dust extinction, as opposed to the FLG prescribed vertical profile, leads to greater and more spatially heterogeneous changes in the estimated radiative forcing and heating rate produced by dust. Both changes can be attributed to a different vertical structure between dust and non-dust source regions. Values of the dust vertically resolved AOD per grid level (VRAOD) are much larger in the middle troposphere, though smaller at the surface when the GEOS-Chem simulated vertical profile is used, which leads to a much stronger heating rate in the middle troposphere. Compared to the FLG vertical profile, the use of GEOS-Chem vertical profile reduces the solar radiative forcing at the top of atmosphere (TOA) by approximately 0.2–0.25 W m−2 over the African and Asian dust source regions. While the Infrared (IR) radiative forcing decreases 0.2 W m−2 over African dust belt, it increases 0.06 W m−2 over the Asian dust belt when the GEOS-Chem vertical profile is used. Differences in the solar radiative forcing at the surface between the use of the GEOS-Chem and FLG vertical profiles are most significant over the Gobi desert with a value of about 1.1 W m−2. The radiative forcing effect of dust particles is more pronounced at the surface over the Sahara and Gobi deserts by using FLG vertical profile, while it is less significant over the downwind area of Eastern Asia.

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Interaction of the Vertical Profile of Dust Aerosols with Land/sea Breezes over the Eastern Coast of the Red Sea from LIDAR and High-resolution WRF-Chem Simulations

10.5194/egusphere-egu2020-2077 ◽

2020 ◽

Author(s):

Sagar Parajuli ◽

Georgiy Stenchikov ◽

Alexander Ukhov ◽

Illia Shevchenko

Keyword(s):

High Resolution ◽

Red Sea ◽

Vertical Profile ◽

Lidar Data ◽

Aerosol Extinction ◽

Vertical Profiles ◽

Sea Breezes ◽

Dust Emissions ◽

Dust Aerosols ◽

Land Breezes

With the advances in modeling approaches, and the application of satellite and ground-based data in dust-related research, our understanding of the dust cycle is significantly improved in recent decades. However, two aspects of the dust cycle, the vertical profiles and diurnal cycles of dust aerosols have not been understood adequately, mainly due to the sparsity of observations. A micro-pulse LIDAR has been operating at the King Abdullah University of Science and Technology (KAUST) campus located on the east coast of the Red Sea (22.3N, 39.1E), measuring the backscattering from atmospheric aerosols at a high temporal resolution for several years since 2015. It is the only operating LIDAR system over the Arabian Peninsula. We use this LIDAR data together with other collocated observations and high-resolution WRF-Chem model simulations to study the 3-d structure of aerosols, with a focus on dust over the Red Sea Arabian coastal plains.&#160;Firstly, we investigate the vertical profiles of aerosol extinction and concentration in terms of their seasonal and diurnal variability. Secondly, using the hourly model output and observations, we study the diurnal cycle of aerosols over the site. Thirdly, we explore the interactions between dust aerosols and land/sea breezes, which are the critical components of the local diurnal circulation in the region.&#160;We found a substantial variation in the vertical profile of aerosols in different seasons. There is also a marked difference in the daytime and nighttime vertical distribution of aerosols in the study site, as shown by LIDAR data. A prominent dust layer is observed at ~5-7km at night in the LIDAR data, corresponding to the long-range transported dust of non-local origin. The vertical profiles of aerosol extinction are consistently reproduced in LIDAR, MERRA-2 reanalysis, and CALIOP data, as well as in WRF-Chem simulations in all seasons. Our results show that the sea breezes are much deeper (~1km) than the land breezes (~200m), and both of them prominently affect the distribution of dust aerosols over the study site. Sea breezes mainly trap the dust aerosols near the coast, brought by the northeasterly trade winds from inland deserts, causing elevated dust maxima at the height of ~1.5km. Also, sea and land breezes intensify dust emissions from the coastal region in daytime and nighttime, respectively. Such dust emissions caused by sea breezes and land breezes are most active in spring and winter. Finally, WRF-Chem successfully captures the onset, demise, and the height of some large-scale dust events as compared to LIDAR data qualitatively.&#160;

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