scholarly journals A numerical study of the transport and diffusion of coastal pollutants during the breeze cycle in the Island of Mallorca

1996 ◽  
Vol 14 (3) ◽  
pp. 351-363 ◽  
Author(s):  
R. Romero ◽  
C. Ramis
Keyword(s):  
Numerical Study ◽  
Ground Level ◽  
North Coast ◽  
Land Breeze ◽  
Local Circulation ◽  
Physical Mechanisms ◽  
The North ◽  
Ground Level Concentration ◽  
Transport And Diffusion ◽  
Reactive Pollutant

Abstract. An Eulerian study of the distribution over the Island of Mallorca of a non-reactive pollutant (SO2) emitted from an electric power plant operating at present on the north coast is performed using a meso-β numerical model, paying particular attention to the diffusive physical mechanisms. The study is applied to the conditions of sea-land breeze development. This is a local circulation that dominates the flow during the summer and favours transporting pollutants from the coast toward the centre of the island. Results indicate that values of the ground-level concentration higher than 5 μ g/m3 are restricted over a limited and mountainous region during the whole diurnal cycle. However, when the simulation is carried out with the inclusion of a twin electric plant which may be built on the south coast, the affected area becomes larger, especially early in the morning, when air over the island is sinking as a consequence of the land breeze development. The inclusion of dry deposition in the simulations does not produce important changes in the spatial and temporal evolution of the ground-level concentration.

scholarly journals A Numerical Study of Mountain-Plain Breeze Circulation in Eastern Chengdu, China

2019 ◽  
Vol 11 (10) ◽  
pp. 2821 ◽  
Author(s):  
Yue Tian ◽  
Junfeng Miao
Keyword(s):  
Cross Sections ◽  
Numerical Study ◽  
Turbulent Transport ◽  
Temperature Inversion ◽  
Turbulent Heat ◽  
Breeze Circulation ◽  
Local Circulation ◽  
Mountain Areas ◽  
Mountain Area ◽  
The North

The spatiotemporal structure and evolution of the thermally-induced mountain-plain breeze circulation in the Longquan Mountain, eastern Chengdu, are studied by the WRF-ARW model based on a two-day case. Turbulence characteristics are also examined to better understand the local circulation of the area. Simulation results show that the 2 m temperature distribution of the plain and mountain areas is peculiar due to the occurrence of the temperature inversion. The plain and mountain breezes can be predicted explicitly by the model, and the consequent circulations are coupled with other factors such as turbulent movement and vertically propagating mountain waves. Owing to this unique terrain feature, the north portion of the mountain demonstrates more evident mountain and plain breezes compared to the south and middle portions. Stronger turbulences are formed over the mountain area compared to the plain area. Vertical cross-sections of turbulent heat, moisture and momentum fluxes show that turbulent transport plays an important role in the development and elimination of mountain-plain breeze circulation.

scholarly journals Numerical study of sediment transport in Thu-Bon estuary and coastal areas of Hoi-An City

2022 ◽  
Vol 964 (1) ◽  
pp. 012001
Author(s):  
Nguyen Thong ◽  
Ho Tuan Duc ◽  
Phan Quang Hung ◽  
Tran Hai Yen
Keyword(s):  
Sediment Transport ◽  
Numerical Study ◽  
Monsoon Season ◽  
Sand Dunes ◽  
Coastal Areas ◽  
Main Trend ◽  
North Coast ◽  
Northeast Monsoon ◽  
The North ◽  
Depth Study

Abstract The area of Cua-Dai estuary and the coastal areas of Hoi-An City have experienced complicated erosion and sedimentation in recent years. Along the coast of Hoi-An, erosion often occurs, whereas in the area of Cua-Dai River, there is an accretion phenomenon that obstructs the waterway navigation from Cua-Dai to Cu-Lao-Cham. Occurrence of sand dunes in the offshore location of Cua-Dai has been recorded at a number of times in recent years. Studying the process of bed morphological change due to the sediment transport in the Thu-Bon river and the influence of monsoons in the area allows to explain the above phenomenon thus an in-depth study to propose appropriate solutions. This study used the numerical model Telemac which combines the hydro-morphodynamic and wave modules. The simulation results show that the main trend of coastal currents caused by tides and waves tends to go southward, leading to coastal erosion especially in the northeast monsoon season as well as sedimentation in the estuarine area. In addition, the model also shows the crucial role of waves in shoreline erosion, with the degree of erosion in the north coast near Cua-Dai being more severe than the southern coast, through the formation of local eddy flow on the north coast.

scholarly journals Critical degradation of Peruvian Plantcutter Phytotoma raimondii habitat in Lobitos, Talara

2020 ◽  
Vol 27 (3) ◽  
pp. 329-337
Author(s):  
Jeremy N. M. Flanagan
Keyword(s):  
Habitat Degradation ◽  
Habitat Type ◽  
Ground Level ◽  
North Coast ◽  
Specialist Herbivore ◽  
Important Species ◽  
Main Site ◽  
The North ◽  
Floral Diversity ◽  
Key Species

The threatened Peruvian Plantcutter Phytotoma raimondii is a restricted-range species, endemic to the north coast of Peru. As a specialist herbivore, it is only found at sites with an adequate diversity of xerophytic flora. Although it is recognized that the species is under threat from habitat degradation and loss, little or no attempt has been made to measure these changes. This study catalogues the floral diversity and degradation of sites near Lobitos town, north of Talara, to determine the loss of this species´ habitat. Fieldwork was conducted between November 2019 and January 2020. All larger plants (with a diameter ≥ 5 cm near ground level) and all deforested Prosopis pallida (Algarrobo) stumps were georeferenced over a 10 ha plot at the main site of Cerro Blanco, c. 2 km south of Lobitos. The height, width and general health of each bush were noted, and the diameter of P. pallida stumps measured. Additionally, two smaller comparative plots, (0.3 and 0.75 ha) were surveyed c. 2.5 km to the north of Lobitos. Results point to an alarming and accelerated rate of degradation of this habitat type due to the deforestation and dieback of P. pallida: a key species in this habitat and important food source for the Plantcutter. Removal of P. pallida appears to affect the stability of sites, with other important species, e.g. Lycium boerhaviifolium (Palo Negro) dying off after logging. Without urgent remedial action, the Peruvian Plantcutter´s habitat will continue to become ever scarcer and more fragmented.

scholarly journals The Secondary Low and Heavy Rainfall Associated with Typhoon Mindulle (2004)

2008 ◽  
Vol 136 (4) ◽  
pp. 1260-1283 ◽  
Author(s):  
Cheng-Shang Lee ◽  
Yi-Chin Liu ◽  
Fang-Ching Chien
Keyword(s):  
Heavy Rainfall ◽  
Numerical Study ◽  
North Coast ◽  
Mountain Range ◽  
Mountain Area ◽  
The North ◽  
Main Circulation ◽  
Upper Level ◽  
The Taiwan Strait ◽  
Strong Vorticity

Abstract This paper presents an observational and numerical study of Typhoon Mindulle (2004) as it affected Taiwan. Mindulle made landfall on the east coast of Taiwan at 1500 UTC 1 July 2004, and after 13 h, it exited Taiwan from the north coast. Severe rainfall (with a maximum amount of 787 mm) occurred over central-southwestern Taiwan on 2 July 2004. During the landfall of Mindulle’s main circulation, a secondary low formed over the Taiwan Strait. However, the secondary low, after it developed significantly (vorticity exceeded 5 × 10−4 s−1 over a 30-km radius), did not replace the original center as was observed in many other storms. Instead, it moved inland and dissipated after the original center redeveloped near the north coast of Taiwan. In this study, the evolution of the secondary low, the redevelopment of the primary center, and the processes leading to the severe rainfall were examined. Results showed that the processes leading to the formation and the development of the secondary low were similar to those described in previous studies. These processes include the leeside subsidence warming, the horizontal transport of vorticity around the northern tip of the Central Mountain Range (CMR), and the overmountain upper-level vorticity remnant. However, because of the northward track, Mindulle preserved some strong vorticity on the eastern slope of the CMR. This strong vorticity remnant was steered northward over the ocean offshore from the north coast where the redevelopment of the primary center occurred. This “quasi-continuous track” of Mindulle has not been documented in previous studies. The vortex interaction between the redeveloped primary center and the secondary low resulted in the northeastward movement of the secondary low, which then dissipated after making landfall. Analyses also showed that even though heavy rainfall would occur over the mountain area when only the southwesterly flow prevailed, as on 3 July 2004, Typhoon Mindulle and the secondary low provided extra convergence that resulted in the west–east-oriented convective bands. These convective bands and the orographic lifting of the circulation associated with the secondary low resulted in the heavy rainfall over the central-western plains area.

MBAH HENDRO KUSUMO BIN SYECH AHMAD MUTAMAKKIN: JEJAK SYIAR ISLAM DI WILAYAH PATI

EMPIRISMA ◽  
2008 ◽  
Vol 27 (2) ◽  
Author(s):  
Fathimatuz Zahra Dan Abdul Azis
Keyword(s):  
Central Region ◽  
Marital Relationship ◽  
Southern Region ◽  
North Coast ◽  
The North ◽  
Trace Back ◽  
Northern Regions ◽  
The One

Pati is a region on the north coast, according to the hypothesis of the researcher, the region is divided into three categories. The northern regions are more religious, the central is more plural, while the southern region is in the middle. In the central region there are many relics of tombs believed to be the those of the Muslim proselytizers in the area of Pati. The one that attracts the researcher is a tomb in the Gambiran area, where there are five local Muslim saints buried, one of them belons to mbah Hendro Kusumo, the son of Syech Ahmad Mutamakkin. This article attempts to trace back the spreading of Islam in Pati based on the existence of thetomb of Mbah Hendro Kusumo. It wants to answer question of whethere the existence of his tomb is due to his studying there or marital relationship, and how it relates to the spreading of Islam.Keywords: Mbah Hendro Kusumo, Traces of Islamic Dakwah, Islam

4 The Tyara Site

1968 ◽  
Vol 22 ◽  
pp. 44-79 ◽  
Author(s):  
William E. Taylor
Keyword(s):  
Sandy Beach ◽  
North Coast ◽  
National Museum ◽  
The West ◽  
Rock Outcrops ◽  
Small Boat ◽  
The North

The Tyara site, KkFb-7 in the National Museum catalogue and site file, faces the north coast of the Ungava mainland and rests on the west shore of Sugluk Island (Fig. 1). That island stands about five hundred yards from the mainland and from Sugluk Inlet, one of the few good harbors on that coast. This handsome little island, about one and one-half miles long and as wide, consists of rounded, rugged, hardrock hills that shelter well-vegetated, generally flat-floored valleys. The valleys often contain marshy patches. The shore, of variable incline, is quite jagged, a result of abrupt rock outcrops projecting seaward from brief stretches of sandy beach. The shore facing the mainland is, therefore, quite convenient for small boat use. Dark grey gneisses seem to predominate, although they are often cut by dykes and veins of lighter material, notably quartz. The dense, green valley and hillside vegetation includes willows, mosses, grasses, lichens, and a pleasant profusion of arctic wild flowers (Polunin 1948, Pt. III). I was told at Sugluk that at the head of the inlet, willows, growing in protected situations, reach the thickness of a man's wrist.

Seed production and seedling emergence of Giant Parramatta grass on the north coast of New South Wales

1996 ◽  
Vol 36 (3) ◽  
pp. 299 ◽  
Author(s):  
TS Andrews ◽  
RDB Whalley ◽  
CE Jones
Keyword(s):  
Seed Production ◽  
Seed Bank ◽  
New South ◽  
New South Wales ◽  
Seed Banks ◽  
North Coast ◽  
The North ◽  
South Wales ◽  
Seed Fall ◽  
The Impact

Inputs and losses from Giant Parramatta grass [GPG, Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens] soil seed banks were quantified on the North Coast of New South Wales. Monthly potential seed production and actual seed fall was estimated at Valla during 1991-92. Total potential production was >668 000 seeds/m2 for the season, while seed fall was >146000 seeds/m2. Seed fall >10000 seeds/m2.month was recorded from January until May, with further seed falls recorded in June and July. The impact of seed production on seed banks was assessed by estimating seed banks in the seed production quadrats before and after seed fall. Seed banks in 4 of the 6 sites decreased in year 2, although seed numbers at 1 damp site increased markedly. Defoliation from mid-December until February, April or June prevented seed production, reducing seed banks by 34% over 7 months. Seed banks in undefoliated plots increased by 3300 seeds/m2, although seed fall was estimated at >114 000 seeds/m2. Emergence of GPG seedlings from artificially established and naturally occurring, persistent seed banks was recorded for 3 years from bare and vegetated treatment plots. Sown seeds showed high levels of innate dormancy and only 4% of seeds emerged when sown immediately after collection. Longer storage of seeds after collection resulted in more seedlings emerging. Estimates of persistent seed banks ranged from 1650 to about 21260 seeds/m2. Most seedlings emerged in spring or autumn and this was correlated with rainfall but not with ambient temperatures. Rates of seed bank decline in both bare and vegetated treatment plots was estimated by fitting exponential decay curves to seed bank estimates. Assuming no further seed inputs, it was estimated that it would take about 3 and 5 years, respectively, for seed banks to decline to 150 seeds/m2 in bare and vegetated treatments.

scholarly journals The Potential of GRASP/GARRLiC Retrievals for Dust Aerosol Model Evaluation: Case Study during the PreTECT Campaign

2021 ◽  
Vol 13 (5) ◽  
pp. 873
Author(s):  
Dimitra Konsta ◽  
Alexandra Tsekeri ◽  
Stavros Solomos ◽  
Nikolaos Siomos ◽  
Anna Gialitaki ◽  
...  
Keyword(s):  
Model Evaluation ◽  
Dust Concentration ◽  
Saharan Dust ◽  
North Coast ◽  
Concentration Profiles ◽  
Future Studies ◽  
Aerosol Model ◽  
The North ◽  
Sun Photometer

We use the Generalized Retrieval of Aerosol Surface Properties algorithm (GRASP) to compare with dust concentration profiles derived from the NMME-DREAM model for a specific dust episode. The GRASP algorithm provides the possibility of deriving columnar and vertically-resolved aerosol properties from a combination of lidar and sun-photometer observations. Herein, we apply GRASP for analysis of a Saharan dust outburst observed during the “PREparatory: does dust TriboElectrification affect our ClimaTe” campaign (PreTECT) that took place at the North coast of Crete, at the Finokalia ACTRIS station. GRASP provides column-averaged and vertically resolved microphysical and optical properties of the particles. The retrieved dust concentration profiles are compared with modeled concentration profiles derived from the NMME-DREAM dust model. To strengthen the results, we use dust concentration profiles from the POlarization-LIdar PHOtometer Networking method (POLIPHON). A strong underestimation of the maximum dust concentration is observed from the NMME-DREAM model. The reported differences between the retrievals and the model indicate a high potential of the GRASP algorithm for future studies of dust model evaluation.

scholarly journals Thinner Sea Ice Contribution to the Remarkable Polynya Formation North of Greenland in August 2018

2021 ◽  
Author(s):  
Xiaoyi Shen ◽  
Chang-Qing Ke ◽  
Bin Cheng ◽  
Wentao Xia ◽  
Mengmeng Li ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ice Cover ◽  
Reanalysis Data ◽  
Mean Value ◽  
Ocean Model ◽  
North Coast ◽  
Average Value ◽  
The North ◽  
Wind Sea ◽  
The One

AbstractIn August 2018, a remarkable polynya was observed off the north coast of Greenland, a perennial ice zone where thick sea ice cover persists. In order to investigate the formation process of this polynya, satellite observations, a coupled ice-ocean model, ocean profiling data, and atmosphere reanalysis data were applied. We found that the thinnest sea ice cover in August since 1978 (mean value of 1.1 m, compared to the average value of 2.8 m during 1978–2017) and the modest southerly wind caused by a positive North Atlantic Oscillation (mean value of 0.82, compared to the climatological value of −0.02) were responsible for the formation and maintenance of this polynya. The opening mechanism of this polynya differs from the one formed in February 2018 in the same area caused by persistent anomalously high wind. Sea ice drift patterns have become more responsive to the atmospheric forcing due to thinning of sea ice cover in this region.

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