Abstract: Air pollution is a serious environmental threat on a global scale and can cause harm to human health, morbidity and premature mortality. Reliable monitoring and control systems are therefore necessary to develop coping skills against the hazards associated with this phenomenon. However, existing environmental monitoring means often do not provide a sufficient response due to practical and technical limitations. Commercial microwave links that form the infrastructure for transmitting data between cell phone towers can be harnessed to map rain at high tempo-spatial resolution. Rainfall causes a decrease in the signal strength received by these wireless communication links allowing it to be used as a built-in sensor network to map the phenomenon. In this study, we point to the potential that lies in this system to indirectly monitor areas where air pollution is reduced. The relationship between pollutant wash-off and rainfall provides an opportunity to acquire important spatial information about air quality using existing cell-phone tower signals. Since the density of microwave communication networks is high relative to any dedicated sensor arrays, it could be possible to rely on this available observation tool for studying precipitation scavenging on air pollutants, for model needs and more.
Abstract: The climatic condition over Indian region is highly dependent on monsoon. India receives maximum amount of rainfall during southwest monsoon. Indian economy is highly dependent on agriculture. The presence of flood and drought years influenced the total cultivation system as well as the economy of the country as Indian agricultural systems is still highly dependent on the monsoon rainfall. The present study has been planned to investigate the flood and drought years for the north-west Himalayan region from 1951 to 2014 by using area average Indian Meteorological Department (IMD) rainfall data. For this investigation the Normalized index (NI) has been utilized to find out whether the particular year is drought or flood. The data have been extracted for the north-west Himalayan (NWH) region states namely Uttarakhand (UK), Himachal Pradesh (HP) and Jammu and Kashmir (J&K) to find out the rainy season average rainfall for each year, climatological mean and the standard deviation. After calculation it has been plotted by the diagrams (or graphs) to show the results- some of the years associated with drought years, some are flood years and rest are neutral. The flood and drought years can also relate with the large-scale phenomena El-Nino and La-Lina.
Abstract: High resolution rain data are very important to fulfill the input of hydrological models. Among models of high-resolution rainfall data generation, the temporal disaggregation was chosen for this study. The paper attempts to generate three different rainfall resolutions (4-hourly, hourly and 10-minutes) from daily for around 20-year record period. The process was done by DiMoN tool which is based on random cascade model and method of fragment. Differences between observed and simulated rain dataset are evaluated with variety of statistical and empirical methods: Kolmogorov-Smirnov test (K-S), usual statistics, and Exceedance probability. The tool worked well at preserving the daily rainfall values in wet days, however, the generated data are cumulated in a shorter time period and made stronger storms. It is demonstrated that the difference between generated and observed cumulative distribution function curve of 4-hourly datasets is passed the K-S test criteria while in hourly and 10-minutes datasets the P-value should be employed to prove that their differences were reasonable. The results are encouraging considering the overestimation of generated high-resolution rainfall data.
Abstract: The present study investigates the space-time impact of climate change on the rice crop calendar in tropical Gujranwala, Pakistan. The climate change impact was quantified through the climatic variables, whereas the existing calendar of the rice crop was compared with the phonological stages of the crop, depicted through the time series of the Normalized Difference Vegetation Index (NDVI) derived from Landsat data for the decade 2005-2015. Local maxima were applied on the time series of NDVI to compute the rice phonological stages. Panel models with fixed and cross-section fixed effects were used to establish the relation between the climatic parameters and the time-series of NDVI across villages and across rice growing periods. Results show that the climatic parameters have significant impact on the rice crop calendar. Moreover, the fixed effect model is a significant improvement over cross-sectional fixed effect models (R-squared equal to 0.673 vs. 0.0338). We conclude that high inter-annual variability of climatic variables cause high variability of NDVI, and thus, a shift in the rice crop calendar. Moreover, inter-annual (temporal) variability of the rice crop calendar is high compared to the inter-village (spatial) variability. We suggest the local rice farmers to adapt this change in the rice crop calendar.
Abstract: Climate change has become a major concern across the world as the intensity along with quantity of the rainfall, mean surface temperature and other climatic parameters have been changed not only in Bangladesh but also in the entire globe. Bangladesh has already experienced many natural hazards. Among them changing of rainfall pattern, erratic and heavy rainfalls are very common. But changes of rainfall pattern and its amount is still in question to some extent. This study aimed to unfold how the historical rainfalls varied over time and how would be their future trends. In this context, historical rainfall data (1975-2014) were collected from Bangladesh Metrological Department (BMD) and then a time series model was developed using Box-Jenkins algorithm in IBM SPSS to forecast the future rainfall. From the historical data analysis, this study revealed that the amount of rainfall decreased over the time and shifted to the post monsoons. Forecasted rainfall shows that the pre-monsoon and early monsoon will get drier in future whereas late monsoon and post monsoon will show huge fluctuations in rainfall magnitudes with temporal variations which means Bangladesh will get comparatively drier seasons in future which may be a serious problem for the country as it depends on agriculture.
Abstract: This study quantifies a decrement in freeway capacity during rainfall. Traffic and rainfall data were gathered from Highway Agencies and Wunderground weather service. Three inter-urban freeway sections and its nearest weather stations were selected as experimental sites. Capacity analysis found reductions of maximum and mean pre-breakdown flow rates due to rainfall. The Kruskal-Wallis test also provided some evidence to suggest that the variance in the pre-breakdown flow rate is statistically insignificant. Potential application of this study lies in the operation of real time traffic management schemes such as Variable Speed Limits (VSL), Hard Shoulder Running (HSR), and Ramp Metering System (RMS), where speed or flow limits could be set based on a number of factors, including rainfall events and their intensities.
Abstract: After Yogyakarta earthquake in 2006, the main problem that occurred in the first yard of Prambanan Temple is ponding area that occurred after rainfall. Soil characterization needs to be determined by conducting several processes, especially permeability coefficient (k) in both saturated and unsaturated conditions to solve this problem. More accurate and efficient field testing procedure is required to obtain permeability data that present the field condition. One of the field permeability test equipment is Constant Discharge procedure to determine the permeability coefficient. Necessary adjustments of the Constant Discharge procedure are needed to be determined especially the value of geometric factor (F) to improve the corresponding value of permeability coefficient. The value of k will be correlated with the value of volumetric water content (θ) of an unsaturated condition until saturated condition. The principle procedure of Constant Discharge model provides a constant flow in permeameter tube that flows into the ground until the water level in the tube becomes constant. Constant water level in the tube is highly dependent on the tube dimension. Every tube dimension has a shape factor called the geometric factor that affects the result of the test. Geometric factor value is defined as the characteristic of shape and radius of the tube. This research has modified the geometric factor parameters by using empty material tube method so that the geometric factor will change. Saturation level is monitored by using soil moisture sensor. The field test results were compared with the results of laboratory tests to validate the results of the test. Field and laboratory test results of empty tube material method have an average difference of 3.33 x 10-4 cm/sec. The test results showed that modified geometric factor provides more accurate data. The improved methods of constant discharge procedure provide more relevant results.
Abstract: Flash flood is occurred in short time rainfall interval:
from 1 hour to 12 hours in small and medium basins. Flash floods
typically have two characteristics: large water flow and big flow
velocity. Flash flood is occurred at hill valley site (strip of lowland of
terrain) in a catchment with large enough distribution area, steep
basin slope, and heavy rainfall. The risk of flash floods is determined
through Gridded Basin Flash Flood Potential Index (GBFFPI). Flash
Flood Potential Index (FFPI) is determined through terrain slope
flash flood index, soil erosion flash flood index, land cover flash
floods index, land use flash flood index, rainfall flash flood index.
Determining GBFFPI, each cell in a map can be considered as outlet
of a water accumulation basin. GBFFPI of the cell is determined as
basin average value of FFPI of the corresponding water accumulation
basin. Based on GIS, a tool is developed to compute GBFFPI using
ArcObjects SDK for .NET. The maps of GBFFPI are built in two
types: GBFFPI including rainfall flash flood index (real time flash
flood warning) or GBFFPI excluding rainfall flash flood index.
GBFFPI Tool can be used to determine a high flash flood potential
site in a large region as quick as possible. The GBFFPI is improved
from conventional FFPI. The advantage of GBFFPI is that GBFFPI is
taking into account the basin response (interaction of cells) and
determines more true flash flood site (strip of lowland of terrain)
while conventional FFPI is taking into account single cell and does
not consider the interaction between cells. The GBFFPI Map of
QuangNam, QuangNgai, DaNang, Hue is built and exported to
Google Earth. The obtained map proves scientific basis of GBFFPI.
Abstract: Laura Island, which is located about 50 km away from
downtown, is a source of water supply in Majuro atoll, which is the
capital of the Republic of the Marshall Islands. Low and flat Majuro
atoll has neither river nor lake. It is very important for Majuro atoll to
ensure the conservation of its water resources. However, upconing,
which is the process of partial rising of the freshwater-saltwater
boundary near the water-supply well, was caused by the excess
pumping from it during the severe drought in 1998. Upconing will
make the water usage of the freshwater lens difficult. Thus,
appropriate water usage is required to prevent up coning in the
freshwater lens because there is no other water source during drought. Numerical simulation of water usage applying SEAWAT model
was conducted at the central part of Laura Island, including the water
supply well, which was affected by upconing. The freshwater lens was
created as a result of infiltration of consistent average rainfall. The lens
shape was almost the same as the one in 1985. 0 of monthly rainfall
and variable daily pump discharge were used to calculate the
sustainable pump discharge from the water supply well. Consequently,
the total amount of pump discharge was increased as the daily pump
discharge was increased, indicating that it needs more time to recover
from upconing. Thus, a pump standard to reduce the pump intensity is
being proposed, which is based on numerical simulation concerning
the occurrence of the up-coning phenomenon in Laura Island during
the drought.
Abstract: This study aims at improving the urban hydrological
cycle of the Orléans agglomeration (France) and understanding the
relationship between physical and chemical parameters of urban
surface runoff and the hydrological conditions. In particular water
quality parameters such as pH, conductivity, total dissolved solids,
major dissolved cations and anions, and chemical and biological
oxygen demands were monitored for three types of urban water
discharges (wastewater treatment plant output (WWTP), storm
overflow and stormwater outfall) under two hydrologic scenarios (dry
and wet weather). The first results were obtained over a period of five
months. Each investigated (Ormes, l’Egoutier and La Corne) outfall
represents an urban runoff source that receives water from runoff
roads, gutters, the irrigation of gardens and other sources of flow over
the Earth’s surface that drains in its catchments and carries it to the
Loire River. In wet weather conditions there is rain water runoff and
an additional input from the roof gutters that have entered the
stormwater system during rainfall. For the comparison the results La
Chilesse is a storm overflow that was selected in our study as a
potential source of waste water which is located before the (WWTP). The comparison of the physical-chemical parameters (total
dissolved solids, turbidity, pH, conductivity, dissolved organic
carbon (DOC), concentration of major cations and anions) together
with the chemical oxygen demand (COD) and biological oxygen
demand (BOD) helped to characterize sources of runoff waters in the
different watersheds. It also helped to highlight the infiltration of
wastewater in some stormwater systems that reject directly in the
Loire River. The values of the conductivity measured in the outflow
of Ormes were always higher than those measured in the other two
outlets. The results showed a temporal variation for the Ormes outfall
of conductivity from 1465 μS cm-1 in the dry weather flow to 650 μS
cm-1 in the wet weather flow and also a spatial variation in the wet
weather flow from 650 μS cm-1 in the Ormes outfall to 281 μS cm-1
in L’Egouttier outfall. The ultimate BOD (BOD28) showed a
significant decrease in La Corne outfall from 181 mg L-1 in the wet
weather flow to 95 mg L-1 in the dry weather flow because of the
nutrient load that was transported by the runoff.
Abstract: This study presents the moisture variations of
unbound layers from April 2012 to January 2014 in the Interstate 40
(I-40) pavement section in New Mexico. Three moisture probes were
installed at different layers inside the pavement which measure the
continuous moisture variations of the unbound layers. Data show that
the moisture contents of unbound layers are typically constant
throughout the day and month unless there is rainfall. Moisture
contents of all unbound layers change with rainfall. Change in ground
water table may affect the moisture content of unbound layers which
has not been investigated in this study. In addition, the Level 3
predictions of moisture contents using the Pavement Mechanistic-
Empirical (ME) Design software were compared and found quite
reasonable. However, results presented in the current study may not
be applicable for pavement in other regions.
Abstract: In this paper, we study the rainfall using a time series
for weather stations in Nakhon Ratchasima province in Thailand by
various statistical methods to enable us to analyse the behaviour of
rainfall in the study areas. Time-series analysis is an important tool in
modelling and forecasting rainfall. The ARIMA and Holt-Winter
models were built on the basis of exponential smoothing. All the
models proved to be adequate. Therefore it is possible to give
information that can help decision makers establish strategies for the
proper planning of agriculture, drainage systems and other water
resource applications in Nakhon Ratchasima province. We obtained
the best performance from forecasting with the ARIMA
Model(1,0,1)(1,0,1)12.
Abstract: Climate change will affect the hydrological cycle in
many different ways such as increase in evaporation and rainfalls.
There have been growing interests among researchers to identify the
nature of trends in historical rainfall data in many different parts of
the world. This paper examines the trends in annual maximum
rainfall data from 30 stations in New South Wales, Australia by using
two non-parametric tests, Mann-Kendall (MK) and Spearman’s Rho
(SR). Rainfall data were analyzed for fifteen different durations
ranging from 6 min to 3 days. It is found that the sub-hourly
durations (6, 12, 18, 24, 30 and 48 minutes) show statistically
significant positive (upward) trends whereas longer duration (subdaily
and daily) events generally show a statistically significant
negative (downward) trend. It is also found that the MK test and SR
test provide notably different results for some rainfall event durations
considered in this study. Since shorter duration sub-hourly rainfall
events show positive trends at many stations, the design rainfall data
based on stationary frequency analysis for these durations need to be
adjusted to account for the impact of climate change. These shorter
durations are more relevant to many urban development projects
based on smaller catchments having a much shorter response time.
Abstract: Climate change will affect various aspects of
hydrological cycle such as rainfall. A change in rainfall will affect
flood magnitude and frequency in future which will affect the design
and operation of hydraulic structures. In this paper, trends in subhourly,
sub-daily, and daily extreme rainfall events from 18 rainfall
stations located in Tasmania, Australia are examined. Two nonparametric
tests (Mann-Kendall and Spearman’s Rho) are applied to
detect trends at 10%, 5%, and 1% significance levels. Sub-hourly (6,
12, 18, and 30 minutes) annual maximum rainfall events have been
found to experience statistically significant upward trends at 10%
level of significance. However, sub-daily durations (1 hour, 3 and 12
hours) exhibit decreasing trends and no trends exists for longer
duration rainfall events (e.g. 24 and 72 hours). Some of the durations
(e.g. 6 minutes and 6 hours) show similar results (with upward
trends) for both the tests. For 12, 18, 60 minutes and 3 hours
durations both the tests show similar downward trends. This finding
has important implication for Tasmania in the design of urban
infrastructure where shorter duration rainfall events are more relevant
for smaller urban catchments such as parking lots, roof catchments
and smaller sub-divisions.
Abstract: There is an increasing demand for broadband services
in Indonesia. Therefore, the answer is the use of Ka-Band which has
some advantages such as wider bandwidth, the higher transmission
speeds, and smaller size of antenna in the ground. However, rain
attenuation is the primary factor in the degradation of signal at the
Kaband. In this paper, the author will determine whether the Ka-band
frequency can be implemented in Indonesia which has high intensity
of rainfall.
Abstract: A variety of routing techniques are available to develop surface runoff hydrographs from rainfall. The selection of runoff routing method is very vital as it is directly related to the type of watershed and the required degree of accuracy. There are different modelling softwares available to explore the rainfall-runoff process in urban areas. XPSTORM, a link-node based, integrated stormwater modelling software, has been used in this study for developing surface runoff hydrograph for a Golf course area located in Rockhampton in Central Queensland in Australia. Four commonly used methods, namely SWMM runoff, Kinematic wave, Laurenson, and Time-Area are employed to generate runoff hydrograph for design storm of this study area. In runoff mode of XPSTORM, the rainfall, infiltration, evaporation and depression storage for subcatchments were simulated and the runoff from the subcatchment to collection node was calculated. The simulation results are presented, discussed and compared. The total surface runoff generated by SWMM runoff, Kinematic wave and Time-Area methods are found to be reasonably close, which indicates any of these methods can be used for developing runoff hydrograph of the study area. Laurenson method produces a comparatively less amount of surface runoff, however, it creates highest peak of surface runoff among all which may be suitable for hilly region. Although the Laurenson hydrograph technique is widely acceptable surface runoff routing technique in Queensland (Australia), extensive investigation is recommended with detailed topographic and hydrologic data in order to assess its suitability for use in the case study area.
Abstract: The objectives of the present study were to estimate the microbial-N flow to the small intestine and to predict the digestible organic matter intake (DOMI) in grazing Karayaka sheep based on urinary excretion of purine derivatives (xanthine, hypoxanthine, uric acid, and allantoin) by the use of spot urine sampling under field conditions. In the trial, 10 Karayaka sheep from 2 to 3 years of age were used. The animals were grazed in a pasture for ten months and fed with concentrate and vetch plus oat hay for the other two months (January and February) indoors. Highly significant linear and cubic relationships (P
Abstract: In this paper, a study of slope failures along the Alishan Highway is carried out. An innovative empirical model is developed based on 15-year records of rainfall-induced slope failures. The statistical models are intended for assessing the volume of landslide for slope failure along the Alishan Highway in the future. The rainfall data considered in the proposed models include the effective cumulative rainfall and the critical rainfall intensity. The effective cumulative rainfall is defined at the point when the curve of cumulative rainfall goes from steep to flat. Then, the rainfall thresholds of landslide are established for assessing the volume of landslide and issuing warning and/or closure for the Alishan Highway during a future extreme rainfall. Slope failures during Typhoon Saola in 2012 demonstrate that the new empirical model is effective and applicable to other cases with similar rainfall conditions.
Abstract: Grasslands of Iran are encountered with a vast
desertification and destruction. Some legumes are plants of forage
importance with high palatability. Studied legumes in this project are
Onobrychis, Medicago sativa (alfalfa) and Trifolium repens. Seeds
were cultivated in research field of Kaboutarabad (33 km East of
Isfahan, Iran) with an average 80 mm. annual rainfall. Plants were
cultivated in a split plot design with 3 replicate and two water
treatments (weekly irrigation, and under stress with same amount per
15 days interval). Water entrance to each plots were measured by
Partial flow. This project lasted 20 weeks. Destructive samplings
(1m2 each time) were done weekly. At each sampling plants were
gathered and weighed separately for each vegetative parts. An Area
Meter (Vista) was used to measure root surface and leaf area. Total
shoot and root fresh and dry weight, leaf area index and soil coverage
were evaluated too. Dry weight was achieved in 750c oven after 24
hours. Statgraphic and Harvard Graphic software were used to
formulate and demonstrate the parameters curves due to time. Our
results show that Trifolium repens has affected 60 % and Medicago
sativa 18% by water stress. Onobrychis total fresh weight was
reduced 45%. Dry weight or Biomass in alfalfa is not so affected by
water shortage. This means that in alfalfa fields we can decrease the
irrigation amount and have some how same amount of Biomass.
Onobrychis show a drastic decrease in Biomass. The increases in
total dry matter due to time in studied plants are formulated. For
Trifolium repens if removal or cattle entrance to meadows do not
occurred at perfect time, it will decrease the palatability and water
content of the shoots. Water stress in a short period could develop the
root system in Trifolium repens, but if it last more than this other
ecological and soil factors will affect the growth of this plant. Low
level of soil water is not so important for studied legume forges. But
water shortage affect palatability and water content of aerial parts.
Leaf area due to time in studied legumes is formulated. In fact leaf
area is decreased by shortage in available water. Higher leaf area
means higher forage and biomass production. Medicago and
Onobrychis reach to the maximum leaf area sooner than Trifolium
and are able to produce an optimum soil cover and inhibit the
transpiration of soil water of meadows. Correlation of root surface to
Total biomass in studied plants is formulated. Medicago under water
stress show a 40% decrease in crown cover while at optimum
condition this amount reach to 100%. In order to produce forage in
areas without soil erosion Medicago is the best choice even with a
shortage in water resources. It is tried to represent the growth
simulation of three famous Forage Legumes. By growth simulation
farmers and range managers could better decide to choose best plant
adapted to water availability without designing different time and
labor consuming field experiments.
Abstract: One of the essential sectors of Myanmar economy is
agriculture which is sensitive to climate variation. The most
important climatic element which impacts on agriculture sector is
rainfall. Thus rainfall prediction becomes an important issue in
agriculture country. Multi variables polynomial regression (MPR)
provides an effective way to describe complex nonlinear input output
relationships so that an outcome variable can be predicted from the
other or others. In this paper, the modeling of monthly rainfall
prediction over Myanmar is described in detail by applying the
polynomial regression equation. The proposed model results are
compared to the results produced by multiple linear regression model
(MLR). Experiments indicate that the prediction model based on
MPR has higher accuracy than using MLR.