scholarly journals Spatial Distribution and Temporal Change of PPCPs and Microbial Fecal Indicators as Sewage Markers after Rainfall Events in the Coastal Area of Tokyo

2018 ◽  
Vol 16 (3) ◽  
pp. 149-160 ◽  
Author(s):  
Chomphunut Poopipattana ◽  
Misaki Nakajima ◽  
Ikuro Kasuga ◽  
Futoshi Kurisu ◽  
Hiroyuki Katayama ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Coastal Area ◽  
Temporal Change ◽  
Fecal Indicators ◽  
Rainfall Events

scholarly journals Study on the effect of rainfall spatial variability on runoff modelling

2018 ◽  
Vol 20 (3) ◽  
pp. 577-587 ◽  
Author(s):  
Jun Zhang ◽  
Dawei Han ◽  
Yang Song ◽  
Qiang Dai
Keyword(s):  
Spatial Distribution ◽  
Spatial Variability ◽  
Spatial Information ◽  
Model Performance ◽  
Moran’S I ◽  
Image Size ◽  
Moran's I ◽  
Rainfall Events ◽  
Lumped Model ◽  
Distributed Models

Abstract Rainfall spatial variability was assessed to explore its influence on runoff modelling. Image size, coefficient of variation (Cv) and Moran's I were chosen to assess for rainfall spatial variability. The smaller the image size after compression, the less complex is the rainfall spatial variability. The results showed that due to the drawing procedure and varied compression methods, a large uncertainty exists for using image size to describe rainfall spatial variability. Cv quantifies the variability between different rainfall values without considering rainfall spatial distribution and Moran's I describes the spatial autocorrelation between gauges rather than the values. As both rainfall values and spatial distribution have an influence on runoff modelling, the combination of Cv and Moran's I was further explored. The results showed that the combination of Cv and Moran's I is reliable to describe rainfall spatial variability. Furthermore, with the increase of rainfall spatial variability, the hydrological model performance decreases. Moreover, it is difficult for a lumped model to cope with rainfall events assigned with complex rainfall spatial variability since spatial information is not taken into consideration (i.e. the VIC model used in this study). Therefore, it is recommended to apply distributed models that can deal with more spatial input information.

scholarly journals Sub-hourly rainfall patterns by hyetograph type under distinct climate conditions in Northeast of Brazil: a comparative inference of their key properties

RBRH ◽  
2018 ◽  
Vol 23 (0) ◽  
Author(s):  
Luís Romero Barbosa ◽  
Cristiano das Neves Almeida ◽  
Victor Hugo Rabelo Coelho ◽  
Emerson da Silva Freitas ◽  
Carlos de Oliveira Galvão ◽  
...  
Keyword(s):  
Coastal Area ◽  
Cloud Formation ◽  
Rainfall Events ◽  
Climate Conditions ◽  
Event Time ◽  
Hourly Rainfall ◽  
Rainfall Depth ◽  
Formation Type ◽  
Classification Procedures ◽  
Semi Arid

ABSTRACT The lack of process-based classification procedures may lead to unrealistic hyetograph design due to complex oscillation of rainfall depths when assimilated at high temporal resolutions. Four consecutive years of sub-hourly rainfall data were assimilated in three study areas (Guaraíra, GEB, São João do Cariri, CEB, and Aiuaba, AEB) under distinct climates (very hot semi-arid and tropical wet). This study aimed to define rainfall events (for Minimum Inter-event Time, MIT, and Minimum Rainfall Depth, MRD, equal to 30 min and 1.016 mm, respectively), classify their hyetograph types (rectangular, R, unimodal with left-skewed, UL, right-skewed, UR, and centred peaks, UC, bimodal, B, and shapeless, SL), and compare their key rainfall properties (frequency, duration, depth, rate and peak). A rain pulse aggregation process allowed for reshaping SL-events for six different time spans varying from 2 to 30 min. The results revealed that the coastal area held predominantly R-events (64% events and 49% rainfall depth), in western semi-arid prevailed UL-events (57% events and 63% rainfall depth), whereas in eastern semi-arid mostly were R-events (61% events and 30% rainfall depth) similar to coastal area. It is concluded that each cloud formation type had important effects on hyetograph properties, differentiating them even within the same climate.

Les series du Toarcien-Aalenien du SW du Moyen-Atlas (Maroc); precisions stratigraphiques et signification paleogeographique

2001 ◽  
Vol 172 (6) ◽  
pp. 723-736 ◽  
Author(s):  
Hassan El Arabi ◽  
Benali Ouahhabi ◽  
Andre Charriere
Keyword(s):  
Spatial Distribution ◽  
Coastal Area ◽  
Structural Features ◽  
The Other ◽  
Southwestern Part ◽  
Marine Deposits ◽  
South West ◽  
Middle Atlas ◽  
Lateral Variations ◽  
Recent Synthesis

Abstract Toarcian and Aalenian deposits from south west of the Middle Atlas named "Couches du Seloum", were classically considered as a "border facies" of the Middle Atlas trough, which was extensively developed in the northern part of the folded Middle Atlas. Both studies realized on the border of the Bekrit-Timahdite syncline and the Iguer Awragh-Afennourir syncline, allow to specify the stratigraphy, the spatial distribution of deposits and to reconsider the paleogeographic organization of this "border" in the integral context of the northern Middle Atlas trough during the Toarcian and the lower Bajocian interval. A lithostratigraphic succession of the "Couches du Selloum" raised in the western part of Bekrit-Timahdite syncline shows the superposition of three units. Unit 1 is made of clay, reddish and gray marl, locally gypseous, assigned to the lower Toarcian. Unit 2 is essentially composed of a subnodular calcareous series, which consists of discontinuous, wavy and upward-thickening beds. The upper offshore is the most frequent environment. It is mainly made of crinoidal calcarenites, yielding some ammonites and brachiopods rich levels. The Middle Toarcian (Bifrons zone and Gradata zone) was identified in the lower part of this unit. Most of the upper Toarcian zones were distinguished (Speciosum zone, Meneghinii zone and Aalensis zone), they are represented in the upper part by brachiopods (Stroudithyris) and ammonites (Hammatoceras, Dumortieria and Catulloceras) rich set. On several lateral sections, the uppermost part of these pseudo nodular limestones is dated from Opalinum zone (levels with Leioceras and Tmetoceras). Unit 3 shows several facies: bioclastic calcarenites arranged in decimetrics beds, showing cross stratifications; microsparitic limestones in thick beds with silexites. The macrofauna is scarce, often represented by some crinoidal and mollusks fragments; some Zoophycos appear in the top bed of the set. The following deposits illustrate the evolution from the shoreface to the upper offshore. This unit is overlain by a sedimentary discontinuity, materialized by a boring surface, some pockets of accumulations with belemnites and a cover of ferruginous nodules. Ammonites drowned on the discontinuity surface or in the basis of the first interbedded marls which overlies this surface sign the Aalenian-Bajocian transition (top of the Concavum zone and the basis of Discites zone). Immediately above we found some index fauna of the Laeviuscula zone. The series overlaying the "Couches du Selloum" comprises thinning up alternations of limestone/marl, passing progressively to the "Marnes de Boulmane" Formation. Lateral variations and interpretations; SW to NE variations: The thickness and facies variations observed in the Bekrit-Timahdite syncline (C1 to C9), denote the existence of marine intervals generally more dilated, with some marly deposits developed towards the SW; on the contrary towards the NE, series are exclusively calcareous, reduced in thickness, and often condensed in their upper part. The same evolution is observed between the deposits of the Iguer Awragh syncline to the SW and those of Afennourir in the NE [Benshili et al., 1999]. SE to NW variations: Some observations realized in a Toarcian-Aalenian outcrop recently discovered in the sector of Outghalline (C11), shows that an uplifted area separates the marly basin of Bekrit from the Iguer Awragh one. Such variations denote a partition of the Toarcian Selloum basin, located in south west of the Middle Atlas trough, into several entities which are regrouped under the denomination of "Blocks of Selloum"; two NE-SW trending notably subsiding gutters are recognized, the Iguer Awragh-Afennourir and the Bekrit-Timahdite, separated by a shoal (ridge of Ijadrane). Paleogeographic framework of the SW border of the Middle Atlas trough: A synthesis of the geometry of the "Blocks of Selloum" and some paleogeographic and structural features of the NW border of the Middle Atlas trough, as they appear in a recent synthesis [Benshili, 1989; Elmi et al., 1989; Benshili et Elmi, 1994; Charriere, 1990; Fedan, 1993; Laadila, 1996; Sabaoui, 1998; El Arabi et al., 1999], is shown in 3 episodes from Toarcian to Aalenian. The southwestern part of the Middle Atlas studied here, does not appear in any case as a coastal area surrounding the Middle Atlas trough, but like a gulf occupied by marine deposits which is isolated from the Middle Atlas trough by the shoal areas called the "Haut-fond de Boulmane". In the Middle Atlas trough, the sequences prograde in a NE direction and show blocks tilting generally towards the same direction. On the other hand, in the "Blocks of Selloum" the tilting acts toward the SW, against the direction of the global Tethyan polarity.

Statistics of Heavy Rainfall Occurrences in Taiwan

2007 ◽  
Vol 22 (5) ◽  
pp. 981-1002 ◽  
Author(s):  
Ching-Sen Chen ◽  
Yi-Leng Chen ◽  
Che-Ling Liu ◽  
Pay-Liam Lin ◽  
Wan-Chin Chen
Keyword(s):  
Spatial Distribution ◽  
Seasonal Variations ◽  
Heavy Rainfall ◽  
Late Summer ◽  
Rainfall Events ◽  
Orographic Effects ◽  
Hourly Rainfall ◽  
Monsoon Flow ◽  
Rainfall Occurrences ◽  
Heavy Rainfall Events

Abstract The seasonal variations of heavy rainfall days over Taiwan are analyzed using 6-yr (1997–2002) hourly rainfall data from about 360 rainfall stations, including high-spatial-resolution Automatic Rainfall and Meteorological Telemetry System stations and 25 conventional stations. The seasonal variations and spatial variations of nontyphoon and typhoon heavy rainfall occurrences (i.e., the number of rainfall stations with rainfall rate >15 mm h−1 and daily accumulation >50 mm) are also analyzed. From mid-May to early October, with abundant moisture, potential instability, and the presence of mountainous terrain, nontyphoon heavy rainfall days are frequent (>60%), but only a few stations recorded extremely heavy rainfall (>130 mm day−1) during the passage of synoptic disturbances or the drifting of mesoscale convective systems inland. During the mei-yu season, especially in early June, these events are more widespread than in other seasons. The orographic effects are important in determining the spatial distribution of heavy rainfall occurrences with a pronounced afternoon maximum, especially during the summer months under the southwesterly monsoon flow. After the summer–autumn transition, heavy rainfall days are most frequent over northeastern Taiwan under the northeasterly monsoon flow. Extremely heavy rainfall events (>130 mm day−1) are infrequent during the winter months because of stable atmospheric stratification with a low moisture content. Typhoon heavy rainfall events start in early May and become more frequent in late summer and early autumn. During the analysis period, heavy rainfall occurrences are widespread and dominated by extremely heavy rainfall events (>130 mm day−1) on the windward slopes of the storm circulations. The spatial distribution of typhoon heavy rainfall occurrences depends on the typhoon track with very little diurnal variation.

scholarly journals High Resolution Numerical Model for Salinity Transport in Rivers During a Tsunami Attack

2018 ◽  
Vol 13 (4) ◽  
pp. 767-779
Author(s):  
Hiroshi Nagashima ◽  
Nozomu Yoneyama ◽  
◽  
Keyword(s):  
Spatial Distribution ◽  
Temporal Change ◽  
Saline Water ◽  
Three Dimensional ◽  
Specific Area ◽  
Two Dimensional ◽  
Tsunami Propagation ◽  
Salinity Transport ◽  
Propagation Analysis ◽  
Potential Damage

In the event of a tsunami, saltwater flows into rivers and water purification plants must stop taking water from rivers to prevent entry of saline water into the plant owing to potential damage to machinery and contamination of the system. This leads to interruption of water supply during disaster. In this study, a salinity transport simulation model that can carry out a three-dimensional salinity behavior analysis in a specific area and a horizontal two-dimensional tsunami propagation analysis simultaneously was developed to predict saltwater behavior in rivers during a tsunami. These models are structured so that the influence of the boundary of the 3D domain can be excluded without significantly increasing the calculation load. The model was used to simulate saltwater behavior in the Yodo River in Japan during a tsunami. The spatial distribution and temporal change of saltwater under various river flows were quantitatively predicted, and the effectiveness of possible countermeasures in diminishing the duration of water-intake shutdown and the presence of brackish water in upstream areas was assessed.

scholarly journals SPATIAL DISTRIBUTION OF SOME CHEMICAL CHARACTERISTICS OF AN ACID SULFATE SOIL-AFFECTED BRACKISHWATER PONDS IN THE COASTAL AREA OF LUWU REGENCY SOUTH SULAWESI PROVINCE

2014 ◽  
Vol 9 (1) ◽  
pp. 73
Author(s):  
Erna Ratnawati ◽  
Akhmad Mustafa
Keyword(s):  
Spatial Distribution ◽  
Coastal Area ◽  
Soil Nutrient ◽  
Simple Random Sampling ◽  
Soil Characteristics ◽  
Chemical Characteristics ◽  
Acid Sulfate Soil ◽  
Acid Sulfate ◽  
South Sulawesi ◽  
Brackishwater Pond

Spatial distribution of brackishwater pond soil has important role in the system of bioenvironment including brackishwater pond environment. This research was aimed to determine the spatial distribution of some chemical characteristics of an acid sulfate soil-affected brackishwater pond in coastal area of Luwu Regency South Sulawesi Province, Indonesia. ALOS AVNIR-2 images (acquisition 16 May 2008, 16 October 2008, 17 September 2009) were integrated with Indonesian Topographic maps to obtain base map. Sampling soil points were determined by simple random sampling in 104 points for two different soil depths i.e. 0-0.2 m and 0.5-0.7 m. A total of 18 soil chemical characteristics was measured in the field and analyzed in the laboratory. Geostatistic using kriging method in the ArcGIS 9.3 software was used to interpolate the data. The results of this study indicated that in general pond soil chemical characteristics in Luwu Regency could be categorized with high variability or relatively heterogenic wi th the value of var iation coefficient more than 36%. The soil characteristics that explain acidity had shown similar pattern in spatial distribution as well as other soil characteristics with soil nutrient. The high value of pH and low value of PO4 were generally found in the northern part of Luwu Regency, including East Lamasi, East Walenrang, Bua, and Ponrang Subdistricts. It is recommended that soil management in brackishwater ponds of Luwu Regency could be based on soil chemical characteristics so its could improve the production through minimizing the input, increasing carrying capacity, and avoiding environmental degradation.

scholarly journals Specific composition, numbers and biotopical distribution of snakes (Serpentes) on the southern slope of the Navagir mountain ridge (Abrau Peninsula) and some problems of its preservation

2021 ◽  
Vol 21 (3/4) ◽  
pp. 144-150
Author(s):  
A. Yu. Tsellarius ◽  
Keyword(s):  
Spatial Distribution ◽  
Species Composition ◽  
Coastal Area ◽  
Middle Part ◽  
Mediterranean Vegetation ◽  
Southern Slope ◽  
Mountain Ridge ◽  
Specific Composition ◽  
Biotopical Distribution

Seven species of snakes were revealed in 1997–1998, six of which (Natrix tessellata, N. natrix, Zamenis longissimus, Hierophis caspius, Platyceps najadum, and Elaphe sauromatus) were in the lower part of the slope, in the area of mediterranean vegetation. In 2001– 2003, the first three species were revealed only, and their numbers significantly decreased, reaching a maximum in the middle part of the slope, in the zone of transition from mediterranean vegetation to broad-leaved forests. In 1999–2000, the recreational load on the coastal area sharply rose, which probably was the cause for the species composition reduction and changes of the spatial distribution in snakes.

Assessment of »True« Variability of Small Rainfall Events in a Small Mountainous Watershed in the Summer

1982 ◽  
Vol 13 (4) ◽  
pp. 205-212 ◽  
Author(s):  
Lawrence C. Nkemdirim ◽  
Brian D. Meller
Keyword(s):  
Spatial Distribution ◽  
Standard Error ◽  
Rain Gauge ◽  
Rainfall Amount ◽  
Rainfall Events ◽  
Mountainous Watershed ◽  
Rainfall Volume ◽  
Areal Rainfall ◽  
The Relationship ◽  
Rain Gauge Network

The standard error of mean areal rainfall was calculated for various densities of rain gauge network in a small mountainous watershed in the summer of 1978. It is shown that a) the optimum gauge density required to assess mean rainfall is about 3 gauges/km2; b) the »true« variability in the spatial distribution of rainfall decreases with increasing rainfall amount; and c) the relationship between »true« variability and rainfall volume is linear in that watershed.

Spatial Distribution and Temporal Change of Extreme Precipitation Events on the Koshi Basin of Nepal

2018 ◽  
Vol 17 (1) ◽  
pp. 38-46
Author(s):  
Sanjeevan Shrestha ◽  
Tina Baidar
Keyword(s):  
Adverse Effect ◽  
Spatial Distribution ◽  
Extreme Events ◽  
Extreme Precipitation ◽  
Temporal Change ◽  
Extreme Weather Events ◽  
Extreme Precipitation Events ◽  
Increasing Trend ◽  
Koshi Basin ◽  
Precipitation Events

Climate change, particularly at South Asia region is having a huge impact on precipitation patterns, its intensity and extremeness. Mountainous area is much sensitive to these extreme events, hence having adverse effect on environment as well as people in term of fluctuation in water supply as well as frequent extreme weather events such as flood, landslide etc. So, prediction of extreme precipitation is imperative for proper management. The objective of this study was to assess the spatial distribution and temporal change of extreme precipitation events on Koshi basin of Nepal during 1980-2010. Five indicators (R1day, R5 day, R > 25.4 mm, SDII and CDD) were chosen for 41 meteorological stations to test the extreme events. Inverse distance weighting and kriging interpolation technique was used to interpolate the spatial patterns. Result showed that most extreme precipitation events increased up to mountain regions from low river valley; and then it decreased subsequently up to Himalayan regions (south to north direction). However, there is high value of indices for lowland Terai valley also. Most of the indices have hotspot with higher value at north western and southern part of the study area. For temporal change, most of the extreme precipitation indices showed increasing trend within 30 years’ period. The spatial distribution of temporal change in indices suggests that there is increasing trend in lowland area and decreasing trend in mountainous and Himalayan area. So, adaptive measure should be adopted through proper land use planning, especially at those hotspot areas and their tributaries; to reduce adverse effect of extreme precipitation events.

Bi-temporal change analysis of satellite imagery to detect landslides triggered by intense rainfall events

2016 ◽  
Vol 39 ◽  
pp. 51-54
Author(s):  
Leonardo Disperati ◽  
Filippo Gregori ◽  
Massimo Perna ◽  
Francesco Manetti ◽  
Guido Lavorini ◽  
...  
Keyword(s):  
Satellite Imagery ◽  
Temporal Change ◽  
Intense Rainfall ◽  
Change Analysis ◽  
Rainfall Events ◽  
Temporal Change Analysis
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