Horizontal and vertical distributions of planktic foraminifera in the subarctic Pacific

2017 ◽  
Vol 130 ◽  
pp. 1-14 ◽  
Author(s):  
Shinya Iwasaki ◽  
Katsunori Kimoto ◽  
Azumi Kuroyanagi ◽  
Hodaka Kawahata
2008 ◽  
Vol 8 (13) ◽  
pp. 3603-3622 ◽  
Author(s):  
F. Lasserre ◽  
G. Cautenet ◽  
C. Bouet ◽  
X. Dong ◽  
Y. J. Kim ◽  
...  

Abstract. In order to assess the complex mixing of atmospheric anthropogenic and natural pollutants over the East Asian region, we present a modelling tool which takes into account the main aerosols which are to be found simultaneously over China, Korea and Japan during springtime. Using the mesoscale RAMS (Regional Atmospheric Modeling System) tool, we present a simulation of natural (desert) dust events along with some of the most critical anthropogenic pollutants over East Asia, sulphur elements (SO2 and SO2-4) and Black Carbon (BC). As regards a one-week case study of dust events which occurred during late April 2005 over an area extending from the Gobi deserts to the Japan surroundings, we satisfactorily model the behaviours of the different aerosol plumes. We focus on possible dust mixing with the anthropogenic pollutants from megacities. For both natural and anthropogenic pollution, the model results are in fairly good agreement with the horizontal and vertical distributions of concentrations as measured by in situ LIDAR, and as observed in remote data, PM10 data and literature. In particular, we show that a simplified chemistry approach of this complex issue is sufficient to model this event, with a real-time step of 3 h. The model reproduces the main patterns and orders of magnitude for Aerosol Optical Thickness (AOT) and species contributions (via the Angström Exponent) when compared with the AErosol RObotic NETwork (AERONET) data.


2017 ◽  
Vol 584-585 ◽  
pp. 154-163 ◽  
Author(s):  
Intae Kim ◽  
Doshik Hahm ◽  
Keyhong Park ◽  
Youngju Lee ◽  
Jung-Ok Choi ◽  
...  

Chemosphere ◽  
2017 ◽  
Vol 184 ◽  
pp. 244-252 ◽  
Author(s):  
Takashi Tomiyasu ◽  
Hitoshi Kodamatani ◽  
Ryusuke Imura ◽  
Akito Matsuyama ◽  
Junko Miyamoto ◽  
...  

1977 ◽  
Vol 7 (4) ◽  
pp. 680-699 ◽  
Author(s):  
Lawrence H. Pike ◽  
Robert A. Rydell ◽  
William C. Denison

Methods have been developed to yield total tree estimates of biomass for various components of a tree (trunk, axes, twigs, and needles) and its community of epiphytes (microorganisms, lichens, and bryophytes). Trees were sampled with the help of climbing techniques modified from mountain climbing. Two stages of sampling were involved. First, all units of the population were described so that their weights could be predicted. Second, several units were chosen with probability of selection dependent upon predicted weight and sampled in detail. Biomass estimates from the sampled units were expanded to tree totals with information gathered during the first sampling stage. Internal structure of the crown (tree components and epiphytes) is illustrated by maps of trunk and branch systems and by diagrams of horizontal and vertical distributions. This internal structure was also derived from the first sampling stage.These methods have been applied to nine old-growth Douglas fir trees (Pseudotsugamenziesii (Mirb.) Franco). Data from a single 400-year-old tree (1.46 m dbh, 77 m in height) in the H. J. Andrews Experimental Forest in the western Cascade Mountains of Oregon are presented. Biomass and surface area estimates are as follows: trunk, 26 870 kg, 223 m2; axes (>4 cm), 1530 kg, 81 m2; living twigs (<4 cm), 480 kg, 373 m2; dead twigs, 78 kg, 104 m2; needles, 198 kg, 2860 m2; lichens, 13.1 kg; and bryophytes, 4.7 kg. Total cell volume of microepiphytes on twigs was estimated to have been 300 cm3 and total cover by microepiphytes on needles was estimated to have been 191 m2.


2004 ◽  
Vol 84 (6-7) ◽  
pp. 441-456 ◽  
Author(s):  
Massimo Del Bubba ◽  
Alessandra Cincinelli ◽  
Leonardo Checchini ◽  
Luciano Lepri ◽  
Piergiorgio Desideri

2017 ◽  
Vol 50 (2) ◽  
pp. 1052
Author(s):  
A. Tsikerdekis ◽  
P. Zanis ◽  
L.A. Steiner ◽  
V. Amiridis ◽  
E. Marinou ◽  
...  

In the present study we are simulating the trans-Atlantic transport of dust from Sahara to the South-Central America, using the regional climate model RegCM4 and its online dust scheme, for the year 2007. The simulated horizontal and vertical distributions of the mineral dust optical properties were evaluated against the LIVAS CALIPSO satellite dust product. The Trans-Atlantic dust transport is simulated adequately with RegCM4, but there are some spatial discrepancies. Dust optical thickness is overestimated in the eastern Sahara throughout the year by 0.1-0.2, while near the gulf of Guinea is underestimated during winter and spring. Although RegCM4 dust plume is located southern on winter and spring, it doesn't spatially match the dust optical thickness of LIVAS. In summer and autumn the vertical distribution of dust between 3-4km during the Trans-Atlantic transport is simulated by the model adequately up to 30ºW 40ºW longitude. However, during winter-spring RegCM4 misplaces dust loading into higher altitude. Finally, we discuss some possible reasons and mechanisms that might be responsible for the differences between the model and the observations. 


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