Rainfall Height Research Articles

INFLUENCE OF CLIMATIC ACCIDENTS ON THE FREQUENCY OF CROP REGROWTH IN THE KABOUA DISTRICT (SAVE COMMUNE), BENIN

The Kaboua arrondissement is facing increasing challenges related to climate incidents, such as droughts, floods, and temperature variations. These events disrupt not only traditional cropping cycles but also affect the frequency of crop regrowth, which is essential for food security and the income of local farmers. The general objective of this research is to analyze the influence of climate incidents on crop regrowth in the study area. The data used include rainfall heights from 1928 to 2018, as well as maximum and minimum temperatures from 1961 to 2018, all sourced from the Savè meteorological station. This data was collected from Meteo-Benin. Additionally, a survey was conducted among the population of the Kaboua arrondissement to correlate meteorological data with local field observations. The results of this research showed that climate change alters the rainy seasons and growing periods, leading to crop losses and difficulties in maintaining sustainable crop regrowth. It is essential to emphasize that regrowth plays a key role in helping producers cope with food insecurity during the lean season. Furthermore, according to 95% of the surveyed producers, it also helps meet their financial needs. Regrowth is also crucial in the soil fertility cycle, serving as a vital link in the conservation and regeneration of nutrients necessary for crop growth. Its impact on soil health and quality is fundamental to maintaining long-term agricultural productivity.

Climate change effects on rainfall extreme value distribution: the role of skewness

Quantifying the potential effects of Climate Change (CC) on hydrological scales is a topic with a more and more increasing interest for the scientific community, given the CC impact on agriculture, industry, economy, human health, ecosystems, among the others. In this context, the paper focuses on the sub-daily Annual Maxima (AM) of rainfall height time series, and specifically on the crucial role played by initial skewness, i.e. the skewness of the observed rainfall series used to evaluate potential parametric trends. Here a quick and user-friendly methodology is proposed, that is aimed at quantifying plausible future changes in terms of probability distributions assumed at rain gauge scale, from projections of any climatic model. In detail, the Generalized Extreme Value (GEV) and the Two-Component Extreme Value (TCEV) distributions are adopted as probability functions suitable for modelling observed rainfall AM series, which could increase their frequency and magnitude into future horizons under CC. EURO-CORDEX projections for Europe are considered, under the hypothesis that the values of the change factor, i.e. the ratio between the values of a specific quantile at two specific time horizons, are invariant when moving from an areally-averaged scale (typical for any climate model) to a point rain gauge scale, which induces that future changes are provided (in terms of frequency and magnitude of extreme events) without the need of any spatial downscaling from the assumed projections. The proposed methodology can contribute to hazard quantification associated to potential climate changes, and thus it can play a crucial role in the assessment of hydraulic structures resilience; the obtained results, specific for the study area of Italy, but easily extendable on a global scale, showed that larger increases in frequency of future heavy events are expected for time series with “EV1 alike” values of initial skewness.

Probabilistic corrosion hazard maps for reinforced concrete infrastructure in coastal regions

The development of probabilistic corrosion hazard maps for reinforced concrete infrastructure exposed to airborne chlorides in coastal regions is addressed in the present work, with special attention to bridges. The methodology developed in this study consists of three steps. Initially, spatial distribution, construction year, and main features of the existing infrastructure are examined together with the general characteristics of the study area. The second step deals with the elaboration of relevant environmental data, including the direction and height of sea waves, sea salinity, temperature, relative humidity, rainfall, speed and direction of wind, and chloride deposition rates. Corrosion hazard maps are obtained next, wherein the corrosion current density is selected as an intensity measure. Particularly, they are elaborated for an assigned probability of exceedance given the exposure time window and concrete mixture. The presented methodology is applied to develop probabilistic corrosion hazard maps for reinforced concrete bridges exposed to the marine atmosphere at Oahu Island (Hawaii, United States). For this case-study, it is also discussed the correlation between the actual condition rating of the existing concrete bridges and the estimated corrosion hazard levels.

Response of soil aggregate disintegration to antecedent moisture during splash erosion

Soil aggregate breakdown is the initial stage of splash erosion. Preventing aggregate disintegration can effectively control the material source for sediment transport. The impact factors of aggregate disintegration have been partially studied, but the effect of soil moisture content on slaking and physico-chemical dispersion remains unclear. In this study, simulation tests of splash erosion were carried out on three sandy clay loam soils with different years of vegetation restoration (S1, S2 and S3 were 55, 80 and 100 years of reforestation and land restoration, respectively). Three rainfall heights (1.5 m, 2 m and 2.5 m) were used to simulate aggregate disintegration caused by different rainfall kinetic energies. Soil aggregates with five antecedent moisture contents (air drying, 5 %, 10 %, 15 %, and 20 %) were subjected to three different pretreatments: fast wetting (FW), slow wetting (SW) and shaking after prewetting (WS). It was found that the mean weight diameter in the fast wetting (MWDFW) treatment increased and then decreased with increasing moisture content. Aggregate sensitivity to slaking decreased with increasing moisture content. After rainfall, the macroaggregates content (>0.25 mm) increased and then decreased with increasing moisture content. In the S1 sample, the contribution of physico-chemical dispersion to splash erosion was dominant for increasing splash erosion rate at the moisture content of 15–20 %. The slaking contributed more to decreasing splash erosion rate with increasing moisture content in the S2 and S3 samples. This study clarifies the response of slaking and physico-chemical dispersion to moisture content, which is helpful for thoroughly understanding the disintegration mechanisms of soil aggregates.

Assessing short- and long-term modifications of steady-state water infiltration rate in an extensive Mediterranean green roof

Green roof detention capacity is related to the steady-state infiltration rate, is, of the growing medium. With the aim to investigate short- and long-term modifications of the detention capacity of an extensive Mediterranean green roof, three mini-disk infiltrometer (MDI) measurement campaigns were conducted at construction, after one season and after five years of operation. A laboratory experiment was designed to separately measure is in the upper and the lower part of the substrate profile. During the first operating season, field is increased by a factor of 2.4 and 1.9 for near-saturated (applied pressure head, h0 = −30 mm) and quasi-saturated conditions (h0 = −5 mm), respectively. Similar rainfall height did not induce significant modifications in the upper layer of the laboratory columns, even if contribution of small pores to water infiltration tended to increase. Differently, is significantly decreased by a factor of 3.4–5.3 in the lower layer. After the simulated rainfall, the upper layer was less packed (mean bulk density, ρb = 1.083 kg m−3) and the lower layer was more packed (ρb = 1.218 kg m−3) as compared with the initial density (ρb = 1.131 kg m−3) and the lower part enriched in small particles. Short-term modifications in the experimental plot were thus attributed to fine particles washing-off and bulk density decrease in the upper layer, yielding an overall more conductive porous medium. After five years of green roof operation, field is did not further increase thus showing that the washing/clogging mechanism was complete after one season or it was masked by counteracting processes, like root development and hydrophobicity.

Analysis of Flood Hydrograph Metro Sub Watershed with Synthetic Unit Hydrograph Snyder and SCS (Soil Conservation Service) Methods

Metro Sub-watershed is in Malang City. Based on data from BPBD Malang City, flood disasters have continued to increase from 2016 - 2022. The purpose of this research is to analyse the synthetic unit hydrograph (SUH) which will be used as the basis for planning water resources management. The rainfall data used in 2012-2021 with an average maximum rainfall height of 108 mm... Metro sub-watershed with an area of 31.371 km2 and a river length of 42 km and land use data with 59% of the residential. All data will be analysed for SUH in return periods Q2 = 2th, Q5 = 5th, Q10 = 10th, Q25 = 25th, Q50 = 50th, and Q100 = 100th. SUH analysis using HEC-HMS auxiliary program with Snyder and SCS (Soil Conservation Service) methods. The peak discharge results of the SUH in the Snyder method are Q2 = 47.8 m3/s, Q5 = 48.6 m3/s, Q10 = 50.7 m3/s, Q25 = 52.8 m3/s, Q50 = 54.1 m3/s, Q100 = 55.2 m3/s, and in the SCS method are Q2 = 37.5 m3/s, Q5 = 37.9 m3/s, Q10 = 39.8 m3/s, Q25 = 41.8 m3/s, Q50 = 43 m3/s, Q100 = 44 m3/s.

Influence of Infiltrations on the Recharge of the Nkoabang Aquifer Located in the Center Region, Cameroon

Due to the limited reach of the drinking-water delivery network, Yaoundé’s surrounding communities (such as Nkoabang) rely on well water, boreholes, and springs. This study conducted a Thornthwaite water-balance analysis in the watershed in order to understand its hydrology capability and investigated the influence of the flows and infiltrations on the recharge of the aquifer of Nkoabang (Centre Region, Cameroon). The methodology of this work consisted of updating the rainfall and temperature data of the Mvan meteorological station in Yaoundé to carry out the hydrological and water balances of the Nkoabang aquifer and performing the piezometric monitoring of seven wells and one spring in the dry season and the rainy season. The average rainfall height for the period between 1951–2017 was 1577 ± 222 mm, while the monthly temperatures ranged from 22.8 (July) to 25.4 °C (February) for an average of 24.1 °C ± 0.8 °C. The average interannual infiltration was 137 mm, corresponding to an infiltration coefficient of 8.68%. The value of the piezometric levering varies between 706 and 718 m for an average of 711.76 m during the dry season. It fluctuates between 706 and 719 m during the rainy season for an average of 712.95 ± 4.09 m. Irrespective of the season, the highest and lowest values are those of P6 and P3, respectively. Piezometric level values vary little from one season to another but are higher in the rainy season than in the dry season. Wells in the study area generally show small variations in piezometric level amplitude, ranging from 0.4 to 3.3 m with an average of 1.19 ± 1 m. The analysis of the piezometric map of the Nkoabang aquifer shows a flow in the NE-SW direction; storage areas south of the study areas and the water supply area in the peaks and NE of Nkoabang. The daily indicative flow rates of the spring (S) are 0.15 m3 (dry season), which can supply in the dry and rainy seasons 36 to 46 people, respectively, based on a ratio of 0.1 m3 per day per habitant.

Effects of raindrop temperature on the contributions of slaking and mechanical striking to aggregate disintegration during splash erosion

The influence of raindrop temperature on the soil erosion process has been reported. However, the role of raindrop temperature in aggregate disintegration is unclear. The aims of this study are to investigate the effects of raindrop temperatures on soil aggregate disintegration and to evaluate their effects on the contribution of slaking and mechanical striking to splash erosion. Deionized water and ethanol (95%) were employed as raindrop materials to quantify the effects of raindrop temperature on the contributions of slaking and mechanical striking to splash erosion. Raindrop temperatures were set to 2 °C, 10 °C and 20 °C, and the rainfall heights were set to 0.5 m, 1.0 m and 1.5 m. The results showed that the splash erosion rate decreased with increasing temperature in the Loam1 and Loamy sandy. The breakdown rate decreased with increasing temperature in ethanol tests. The influence of temperature on slaking was greater than that on mechanical striking. The contribution rates of mechanical striking and slaking decreased and increased with increasing temperature, respectively. Slaking contributed more to aggregate disintegration at 10 °C and 20 °C, while mechanical striking was the primary contributor at 2 °C in the Loam2 and Loamy sandy. The results provided a deeper understanding of the mechanism of splash erosion and contributed to improving soil erosion prediction models.

Impact of rainfall trends on flood in Agnéby watershed

The aim of this study is to analyse the spatio-temporal evolution of hydro-rainfall variables in the Agnéby watershed in a disturbed climatic context. Rainfall data from the stations of Arrah, Bongouanou, M’Batto, Akoupé, Céchi, Agboville, Adzopé, Sikensi, Abidjan Airport and Dabou as well as hydrometric data from the stations of Agboville, Offoliguié, M’Bessé and Guessiguié were used. The methodological approach is based on the application of independence and trend tests and spatio-temporal analysis of daily rainfall maxima, duration of consecutive rainfall events, number of rainfall events above a threshold and daily flow maxima. The hypothesis of independence justified the relevance of the choice of variables. The trend test showed the dynamic upward evolution of extreme rainfall and the decrease in the duration of consecutive rainy episodes, in the number of rainy episodes and in the flows feeding the main watercourse. Moreover, spatial analysis of daily maximum rainfall amounts above 120 mm, consecutive maximum rainfall amounts above 160 mm and Gumbel rainfall amounts above 190 mm indicated heavy rainfall in the southern part of the watershed. However, a decrease in rainfall is recorded in the areas covered by the stations of Arrah, Bongouanou, M’Batto, Ce chi and Akoupé. An increase in the flood flow calculated from the Generalized Extreme Value (GEV) between 76.60 m3∙s–1 and 225.70 m3∙s–1 is presented in the main river. The spatio-temporal variation in annual rainfall heights showed a high rainfall in the southern part of the watershed with a decrease in rainfall over the decades (1976–1985 and 1996–2005) followed by an increase over the decades (1986–1995 and 2006–2015). Despite the general decrease in rainfall, extreme rainfall has become frequent, causing flooding in the watershed.

Estimation of Intensity-Duration-Frequency (IDF) Curves from Large Scale Atmospheric Dataset by Statistical Downscaling

The study proposes a new approach that combined statistical downscaling, bias correction, and disaggregation of rainfall techniques in order to derive the IDF curve from large scale atmospheric reanalysis data. The applied methodology details the NCEP/NCAR reanalysis dataset being downscaled by an ANN-based approach to estimate the daily rainfall of Izmir. The annual maximum rainfall series of the study area were sampled from the daily downscaled rainfall series. The sampled daily maximum rainfalls were then bias-corrected by the quantile mapping method and disaggregated into the annual maximum standard-duration rainfall heights regarding the rainfalls' scale-invariant properties. Finally, the IDF curves of the study area were determined by using the disaggregated rainfall heights. The results confirmed that the IDF curves dependent on short-duration extreme rainfall heights could be reasonably estimated from the large-scale atmospheric variables using the statistical downscaling approach.

Retraction Note: Neural network–based urban rainfall trend estimation and adolescent anxiety management

The artificial neural network prediction model is a modern prediction method with computational intelligence as the core. Now, the artificial neural network has been applied to various fields. It can play its own role in each field, but the neural network is used in the prediction of rainfall water quality. It is still in its infancy. This article studies the artificial neural network and artificial neural network for water quality prediction. The education system is a very complex mechanism. There are also large differences. The height and space of urban rainfall are prone to variability. This will cause floods and flood disasters. It is very dangerous for the city, and it will also seriously affect the development of the city. Therefore, the artificial neural network is very important for the prediction of rainfall water quality. If we can use the artificial neural network to recognize the temporal and spatial variability of urban rainfall, then flood disasters can be prevented in advance. This paper uses a variety of algorithms and conducts many experiments to discover the small-scale temporal and spatial variation of rainfall in a certain city. The declining mental health status of Chinese adolescents is not optimistic. It is mainly manifested in anxiety, emotional instability, negativity, and psychological disorders. After a long period of observation, it has been found that the psychological problems of adolescents are mainly caused by disharmony in interpersonal relationships. Study pressure is high and emotions cannot be relieved. Therefore, we have conducted special research in these areas, hoping to have a further understanding of the development of anxiety and obtain corresponding solutions to effectively alleviate the psychological problems of adolescents.

Rainfall Investigation by Means of Marine In Situ Gamma-ray Spectrometry in Ligurian Sea, Mediterranean Sea, Italy

Marine in situ gamma-ray spectrometry was utilized for a rainfall study at the W1M3A observing system in Ligurian Sea, Mediterranean Sea, Italy. From 7 June to 10 October 2016, underwater total gamma-ray counting rate (TCR) and the activity concentration of radon daughters 214Pb, 214Bi and potassium 40K were continuously monitored along with ambient noise and meteorological parameters. TCR was proven as a good rainfall indicator as radon daughters’ fallout resulted in increased levels of marine radioactivity during and 2–3 h after the rainfall events. Cloud origin significantly affects TCR and radon progenies variations, as aerial mass trajectories, which extend upon terrestrial areas, result in higher increments. TCR and radon progenies concentrations revealed an increasing non-linear trend with rainfall height and intensity. 40K was proven to be an additional radio-tracer as its dilution was associated with rainfall height. 40K variations combined with 214Bi measurements can be used to investigate the mixing of rain- and seawater. In comparison with measurements in the atmosphere, the application of marine in situ gamma-ray spectrometry for precipitation investigation provided important advantages: allows quantitative measurement of the radionuclides; 40K can be used, along with radon daughters, as a radio-tracer; the mixing of rain- and seawater can be associated with meteorological parameters.

Design of edges in contour and half moons from edaphoclimatic parameters, for the endorrheic basin of lagunas de tajzara - ramsar site 1030

The collection of water is proposed from the design of contour borders and half moons, green infrastructure measures, to reduce surface runoff and increase the availability of water for vegetation. The contour and crescent ridges have land ridges with a trapezoidal section, which follow the contour lines, to compartmentalize the slope into smaller hydrological units, the ends of which are located on contour lines. With the data of maximum rainfall every 24 hours and parameters of Gumbel's Law modified, the equations of maximum daily rainfall height (hdT), rainfall height for a duration ´´t´´ (htT), and the Intensity Duration Frequency curve (ItT), for a duration of t <2h. Then considering the values of basic infiltration, vegetation cover, soil type and hydrological condition, the curve numbers were determined for different soil moisture conditions, later the separation length (L) between the Half Moons, and the borders was calculated. in contour, which were designed by means of 10 configurations between diameter and height, for the two infrastructures, being in Copacabana Valle, the greatest separation distance.

PLUVIOMETRIC VARIABILITY AND EXTREME PRECIPITATION AND DROUGHTS EVENTS IN THE CENTRAL NORTH MESOREGION OF PARANÁ

Extreme precipitation events cause severe damage in both urban and rural areas. The purpose of this work was to analyze rainfall variability and detect the extremes of precipitation and droughts occurrences and relate them to ENSO phenomena in the Central North Mesoregion of Paraná (MRNCP). We used data from 44 weather stations distributed in the area of the study, from 1976 to 2018. Based on the results, it was identified the precipitation has regional discrepancies, concentrating the highest rainfall in the southern portion. The highest annual precipitation was highly correlated with the periods identified as El Niño, and then in neutrality. There were large occurrences of drought by decent, with emphasis on the winter months, especially in August. High rainfall heights recorded within 24 hours in all regions analyzed, especially in the summer and spring months.

Prototype of Rainfall Intensity Measurement Using CCD TSL1401CL Linear Sensor Array

A prototype measurement of rainfall intensity was developed using a CCD TSL1401CL linear sensor array. The prototype consists of a He-Ne laser that functions as a light source, which later is focused by the beam expander and conditioned by a convex lens. Each pixel will receive the same voltage depending on the light intensity so that it produces a decimal value of ADC. This ADC decimal value determines rainfall intensity based on the diameter and velocity of the raindrops. The diameter variations used ranges from 1 mm to 10 mm, while for variations in the height of rainfall are 50 cm, 100 cm, and 150 cm. The test results proved that the greater the decimal value of the ADC is, the smaller the diameter of the raindrops detected will be, and vice versa. The values of the diameter and velocity of were used to obtain the value of rainfall intensity. The percentage value of error measuring rainfall intensity is 3.11% when compared to the rain gauge module is still considered rather accurate. However, direct testing is still needed when rain falls with various types and intensities. Â

Response of soil aggregate disintegration to the different content of organic carbon and its fractions during splash erosion

AbstractAggregate disintegration is a critical process in soil splash erosion. However, the effect of soil organic carbon (SOC) and its fractions on soil aggregates disintegration is still not clear. In this study, five soils with similar clay contents and different contents of SOC have been used. The effects of slaking and mechanical striking on splash erosion were distinguished by using deionized water and 95% ethanol as raindrops. The simulated rainfall experiments were carried out in four heights (0.5, 1.0, 1.5 and 2.0 m). The result indicated that the soil aggregate stability increased with the increases of SOC and light fraction organic carbon (LFOC). The relative slaking and the mechanical striking index increased with the decreases of SOC and LFOC. The reduction of macroaggregates in eroded soil gradually decreased with the increase of SOC and LFOC, especially in alcohol test. The amount of macroaggregates (>0.25 mm) in deionized water tests were significantly less than that in alcohol tests under the same rainfall heights. The contribution of slaking to splash erosion increased with the decrease of heavy fractions organic carbon. The contribution of mechanical striking was dominant when the rainfall kinetic energy increased to a range of threshold between 9 J m−2 mm−1 and 12 m−2 mm−1. This study could provide the scientific basis for deeply understanding the mechanism of soil aggregates disintegration and splash erosion.

人工降雨对湿地植物叶表面颗粒物滞留的影响

现阶段植物滞尘作为治理大气颗粒物污染的有效方法已被广泛接受与应用。已有研究表明，降雨等方式对植物叶表面颗粒物的滞留有着显著的影响，可有效地将颗粒物从叶表面去除，使植物再次具有滞留颗粒物的能力。由于自然降雨难以量化，现有研究大多采用模拟降雨的方式，将降雨特性量化为降雨强度、降雨历时等可控变量，但较少将降雨高度这一变量纳入研究。且大多以森林生态系统或者城市生态系统中常见的乔、灌、草等植物为主要研究对象，而忽略了处于水陆过渡带的湿地生态系统中植物的特殊性。湿地生态系统不仅可通过植物叶片等结构滞留颗粒物，还可依靠增强空气相对湿度促进颗粒物的吸收和积累，导致湿地植物滞尘规律的特殊性。因此，选择北京地区湿地生态系统内的4种常见植物（香蒲、菖蒲、芦苇和黄花鸢尾）作为研究对象，通过人工模拟降雨的方式，将降雨特性量化为降雨高度与降雨强度两个变量，共设置1 m （11 m）、2 m （10 m）两个不同降雨高度，30 mm/h、45 mm/h、60 mm/h三种不同降雨强度，并将颗粒物划分粗颗粒物（10—100 μm）、细颗粒物（3—10 μm）、超细颗粒物（0.4—3 μm）三种粒径范围。通过滤膜法获得单位叶面积颗粒物去除量，探讨人工降雨对湿地植物叶表面颗粒物滞留的影响。主要研究结果如下：（1）颗粒物去除量在粗颗粒物（10—100 μm）粒径范围内最高；（2）所试4种湿地植物中，菖蒲的颗粒物去除量位居前列；（3）只有在一定的范围内，植物叶表面颗粒物去除量才随降雨强度的增加而增加；（4）不同降雨高度下所试湿地植物叶表面颗粒物去除量无明显规律，降雨高度之间无显著差异（P>0.05）。;At the present stage, plant dust retention is widely used as an effective method to control atmospheric particulate pollution. Studies showed that rainfall, with a significant effect on the retention of particulate matter on the leaf surface of plants, could effectively remove particulate matter from the leaf surface and give the leaf surface with the ability to retain particulate matter again. As natural rainfall is difficult to quantify, most existing studies used the simulated rainfall to quantify rainfall characteristics using controllable variables such as rainfall intensity and rainfall duration, but the variable of rainfall height was less commonly included in studies. Most studies focus on plants such as trees, shrubs, and grasses, which are common in forest ecosystems or urban ecosystems, and ignore the special characteristics of plants in wetland ecosystems. Wetland ecosystems not only retain particulate matter through structures such as plant leaves, but also rely on enhancing relative air humidity to promote the uptake and accumulation of particulate matter, leading to the specificity of the dust retention patterns of wetland plants. Thus, this study selected common plants (Typha orientalis., Acorus calamus, Phragmites australis, Iris wilsonii) of the wetland ecosystem in Beijing area as the research object. Through artificial simulation of rainfall, the rainfall characteristics are quantified to two variables, rainfall height and rainfall intensity. Two different rainfall heights were 1 m (11 m) and 2 m (10 m). Three different rainfall intensities included 30 mm/h, 45 mm/h, and 60 mm/h. The particulate matter was divided into three particle size ranges, namely coarse particulate matter(10-100 μm), fine particulate matter(3-10 μm), ultrafine particulate matter(0.4-3 μm). The removed particulate matter per unit leaf area was obtained through the filter membrane method, and the effect of artificial rainfall on the retention of particulate matter on the leaf surface of wetland plants was discussed. The results are as follows:(1) The mass of particulate matter removal was the highest in the range of 10-100 μm, that is, in the coarse particle scale; (2) Among the four wetland plants tested in this study, Acorus calamus ranked the highest in particulate matter removal; (3) The mass of particulate matter removed from plant leaf surfaces increases with increasing rainfall intensity only within a certain range; (4) There was no significant pattern in the removal of particulate matter from the leaf surface of the tested wetland plants with rainfall height, and there was no significant difference between rainfall heights (P>0.05).

Impact of Climate Variability on Water Resources: The Case of Marc Delorme-Cnra Station, Southeast of Ivory Coast

This study aims to characterize the climatic variability in the South-East of Ivory Coast and to show its impact on the supply of water resources. To do this, statistical and hydrological methods were applied to climatic data collected at the Marc DELORME Research Station of the CNRA. The statistical trend tests on this data revealed a significant decrease in precipitation and an increase in temperature, insolation and evaporation. Statistical break methods indicate a rainfall break in 1982 which marks a modification of the rainfall regime thus translating a drop in rainfall of 15%, a recession in the frequency of rainy days in general and in particular in rainfall heights between 10 and 30 mm and greater than 50 mm. This break is accompanied by a shortening of the rainy seasons, with average rainfall durations ranging from 54 days (short rainy season) to 104 days (great rainy season). Despite the disturbances in the different seasons of the year, the monthly rainfall regimes in the area have not changed. The assessment of the effects of drought on water resources using the Standardized Precipitation and Evapotranspiration Index (SPEI) for three-time scales (1 month, 3 months and 12 months) indicates a severe drought ranging from 3% to 7% over the period 1961 to 2018. However, despite the presence of this severe drought, the intensity of the drought was found to be moderate on all time scales. The Thorrnthwaite method was used to highlight the impacts of this climatic variability on the region’s water resources. The average annual recharge estimated at 402 mm, has been reduced to 153 mm during a deficit period, a decrease of about 62%. The average annual runoff, which was 294 mm, fells to 257 mm, a decrease of about 13%. This recorded decrease in the water infiltrated after the rainfall break (1983-2018), explains the heterogeneous decrease in the depth of the water table.

Impact of COVID-19 Event on the Air Quality in Iran

The first novel coronavirus case was confirmed in Iran in mid-February 2020. This followed by the enforcement of lockdown to tackle this contagious disease. This study aims to examine the potential effects of the COVID-19 lockdown on air quality in Iran. From 21st March to 21st April in 2019 and 2020, The Data were gathered from 12 air quality stations to analyse six criteria pollutants, namely O3, NO2, SO2, CO, PM10, and PM2.5. Due to the lack of ground-level measurements, using satellite data equipped us to assess changes in air quality during the study on Iranian megacities, especially in Tehran, i.e., the capital of Iran. In this city, concentrations of primary pollutants (SO2 5–28%, NO2 1–33%, CO 5–41%, PM10 1.4–30%) decreased with spatial variations. Although, still SO2, NO2, and PM10 exceeded the WHO daily limit levels for 31 days, 31 days, and four days, respectively. Conversely, O3 and PM2.5 increased by 0.5–103% and 2–50%. In terms of the national air quality, SO2 and NO2 levels decreased while AOD increased during the lockdown. Unfavourable meteorological conditions hindered pollutant dispersion. Moreover, reductions in the height of planetary boundary layer and rainfall were observed during the lockdown period. Despite the adverse weather conditions, a decrease in primary pollutant levels, confirms the possible improvements on the air quality in Iran.

SISTEM PERINGATAN DINI BANJIR BERDASARKAN KETINGGIAN AIR, DEBIT AIR DAN CURAH HUJAN DILENGKAPI DENGAN SISTEM MONITORING DATA SENSOR

<p><em>The river often overflows during the rainy season and floods very detrimental. For the community. Therefore designed a monitoring tool and water discharge and rainfall intensity. This tool is constructed using a combination of water level sensors, ultrasonic sensors (SRF-05) and water flow to produce a monitoring system that provides participation early banji, make a program that can display the results surface monitoring and air discharge. See flood early and learn about the performance of surface monitoring systems and flood air discharge with faster rainfall and understand the microcontroller in measuring and controlling system. Tests carried out with aquarium prototypes and carried out. Measurement for one day on a continuous basis. Test results show that this tool can be updated reminded of flood early efficiently. With Thus, the tool designed is able to monitor the height of water activity, discharge and rainfall in rivers, programs are made capable run the designed tool and the results of monitoring can be accessed through LCD that is able to visualize water activities and this early permit system able to work to measure the height and air discharger rain and be able to implement data input from sensors too displays data on the state of the river so that it can be monitored through a computer. As well as a microcontroller capable of measuring and controlling the system accurately and input data from sensors in height and air discharge measurements as well. Rainfall intensity can be monitored via computer.</em></p><p> </p><p><strong><em>Keywords: </em></strong><em>Rainfall, </em><em>Water Discharge, Water level, Monitoring</em></p>