A New 60-year 1940/1999 Monthly-Gridded Rainfall Data Set for Africa

The African continent has a very low density of rain gauge stations, and long time-seriesfor recent years are often limited and poorly available. In the context of global change, it is veryimportant to be able to characterize the spatio-temporal variability of past rainfall, on the basis ofdatasets issued from observations, to correctly validate simulations. The quality of the rainfall datais for instance of very high importance to improve the efficiency of the hydrological modeling,through calibration/validation experiments.The HydroSciences Montpellier Laboratory (HSM) has a long experience in collecting andmanaging hydro-climatological data. Thus, HSM had initiated a program to elaborate a referencedataset, in order to build monthly rainfall grids over the African continent, over a period of 60 years(1940/1999). The large quantity of data collected (about 7,000 measurement points were used in thisproject) allowed for interpolation using only observed data, with no statistical use of a referenceperiod. Compared to other databases that are used to build the grids of the Global HistoricalClimatology Network (GHCN) or the Climatic Research Unit of University of East Anglia, UK (CRU),the number of available observational stations (a was significantly much higher, including the end ofthe century when the number of measurement stations dropped dramatically, everywhere.Inverse distance weighed (IDW) was the chosen method to build the 720 monthly grids and amean annual grid, from rain gauges. The mean annual grid was compared to the CRU grid. The gridswere significantly different in many places, especially in North Africa, Sahel, the horn of Africa, andthe South Western coast of Africa, with HSM_SIEREM data (database HydroSciencesMontpellier_Système d’Information Environnementales pour les Ressources en Eau et leurModélisation) being closer to the observed rain gauge values. The quality of the grids computed waschecked, following two approaches—cross-validation of the two interpolation methods, ordinarykriging and inverse distance weighting, which gave a comparable reliability, with regards to theobserved data, long time-series analysis, and analysis of long-term signals over the continent,compared to previous studies. The statistical tests, computed on the observed and gridded data,detected a rupture in the rainfall regime around 1979/1980, on the scale of the whole continent; thiswas congruent with the results in the literature. At the monthly time-scale, the most widely observedsignal over the period of 1940/1999, was a significant decrease of the austral rainy season betweenMarch and May, which has not earlier been well-documented. Thus, this would lead to a furtherdetailed climatological study from this HSM_SIEREM database.

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Spatial reconstruction of semi-quantitative precipitation fields over Africa during the nineteenth century from documentary evidence and gauge data

Quaternary Research ◽

10.1016/j.yqres.2012.03.012 ◽

2012 ◽

Vol 78 (1) ◽

pp. 13-23 ◽

Cited By ~ 47

Author(s):

Sharon E. Nicholson ◽

Douglas Klotter ◽

Amin K. Dezfuli

Keyword(s):

Nineteenth Century ◽

Rain Gauge ◽

African Continent ◽

Documentary Evidence ◽

Proxy Data ◽

Data Set ◽

Spatial Reconstruction ◽

Geographical Regions ◽

Gauge Data

AbstractThe article presents a newly created precipitation data set for the African continent and describes the methodology used in its creation. It is based on a combination of proxy data and rain gauge records. The data set is semi-quantitative, with a “wetness” index of − 3 to + 3 to describe the quality of the rainy season. It covers the period AD 1801 to 1900 and includes data for 90 geographical regions of the continent. The results underscore a multi-decadal period of aridity early in the nineteenth century.

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Assessing Near Real-Time Satellite Precipitation Products for Flood Simulations at Sub-Daily Scales in a Sparsely Gauged Watershed in Peruvian Andes

Remote Sensing ◽

10.3390/rs13040826 ◽

2021 ◽

Vol 13 (4) ◽

pp. 826 ◽

Cited By ~ 1

Author(s):

Harold Llauca ◽

Waldo Lavado-Casimiro ◽

Karen León ◽

Juan Jimenez ◽

Kevin Traverso ◽

...

Keyword(s):

Real Time ◽

Hydrological Modeling ◽

Early Warning Systems ◽

Rain Gauge ◽

Peruvian Andes ◽

Satellite Precipitation ◽

Daily Precipitation Data ◽

Flood Simulations ◽

Hydrometric Station

This study investigates the applicability of Satellite Precipitation Products (SPPs) in near real-time for the simulation of sub-daily runoff in the Vilcanota River basin, located in the southeastern Andes of Peru. The data from rain gauge stations are used to evaluate the quality of Integrated Multi-satellite Retrievals for GPM–Early (IMERG-E), Global Satellite Mapping of Precipitation–Near Real-Time (GSMaP-NRT), Climate Prediction Center Morphing Method (CMORPH), and HydroEstimator (HE) at the pixel-station level; and these SPPs are used as meteorological inputs for the hourly hydrological modeling. The GR4H model is calibrated with the hydrometric station of the longest record, and model simulations are also verified at one station upstream and two stations downstream of the calibration point. Comparing the sub-daily precipitation data observed, the results show that the IMERG-E product generally presents higher quality, followed by GSMaP-NRT, CMORPH, and HE. Although the SPPs present positive and negative biases, ranging from mild to moderate, they do represent the diurnal and seasonal variability of the hourly precipitation in the study area. In terms of the average of Kling-Gupta metric (KGE), the GR4H_GSMaP-NRT’ yielded the best representation of hourly discharges (0.686), followed by GR4H_IMERG-E’ (0.623), GR4H_Ensemble-Mean (0.617) and GR4H_CMORPH’ (0.606), and GR4H_HE’ (0.516). Finally, the SPPs showed a high potential for monitoring floods in the Vilcanota basin in near real-time at the operational level. The results obtained in this research are very useful for implementing flood early warning systems in the Vilcanota basin and will allow the monitoring and short-term hydrological forecasting of floods by the Peruvian National Weather and Hydrological Service.

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Measuring gravity on ice: An example from Wanapitei Lake, Ontario, Canada

Geophysics ◽

10.1190/1.2189387 ◽

2006 ◽

Vol 71 (3) ◽

pp. J23-J29 ◽

Cited By ~ 3

Author(s):

Hernan A. Ugalde ◽

Elizabeth L’Heureux ◽

Richard Lachapelle ◽

Bernd Milkereit

Keyword(s):

Large Scale ◽

Field Measurements ◽

Noise Sources ◽

Large Lakes ◽

Data Set ◽

Long Time ◽

Calm Wind ◽

Regional Gravity ◽

The Impact

Large lakes have always represented a problem for regional gravity databases; the difficulty of access means gaps or coarse spacing in the sampling. Satellite, airborne, and shipborne gravity techniques are options, but the resolution and/or cost of these systems make them impractical or inaccurate for exploration or environmental studies, where the required resolution is [Formula: see text]. In this study, the feasibility of a ground gravity survey over a frozen lake where ice moves because of windy conditions is assessed. Lake Wanapitei, widely accepted as resulting from the impact of a meteorite 37 million years ago, is one of these cases in which the necessity of expanding coverage over poorly sampled regions arose from a significant gap between surface and airborne geophysical maps. Two gravity surveys were completed on the ice of Lake Wanapitei in the winters of 2003 and 2004. To study the structure, longtime series of gravity field measurements were recorded for 98 stations, allowing for improved control over the noise sources in the data. Final processing and integration with an existing regional data set in the area and the application of terrain corrections reduced the amplitude of the circular anomaly from 15 to [Formula: see text] and its diameter from 11 to [Formula: see text]. The feasibility of gravity surveys on ice was assessed, and we determined that for large-scale studies such as this one, the quality of the data, even under noisy conditions, was acceptable. However, for more detailed mapping, calm wind conditions and long time series are required.

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Chemical composition of rainwater harvested in East Malaysia

Environmental Engineering Research ◽

10.4491/eer.2020.508 ◽

2021 ◽

Vol 27 (2) ◽

pp. 200508-0

Author(s):

Siti Nor Fazillah Abdullah ◽

Azimah Ismail ◽

Hafizan Juahir ◽

R Badlishah Ahmad ◽

Fathurrahman Lananan ◽

...

Keyword(s):

Chemical Composition ◽

Rainwater Harvesting ◽

Water Source ◽

Rain Gauge ◽

Data Set ◽

Rainfall Index ◽

East Malaysia ◽

Secondary Aerosols ◽

Alternative Water

As part of the implementation of a rainwater harvesting system as an alternative water source supply for non-potable use, therefore the characteristic of chemical compounds was significantly explored. The Department of Chemistry, Malaysia, gave the data set for three years (2017-2019). Some chemometric techniques, including PCA, were performed to identify the dimensionality of the rainwater data, hence establishing the rainfall index's purity to determine the quality of rainwater in the study area. Discriminant analysis managed to differentiate each rain gauge station. Cluster analysis was then applied to perform smaller group of rain gauge stations. The result demonstrates that sea salt, secondary aerosols, trace metals, crustal origin, and organic acid dominated the dimensionality of rainwater data with a total variance of 53.38% and indicated that the PRI was significantly diversified into good purity of rainfall index (GPRI), (Labuan and Danum Valley), moderate purity of rainfall index (MPRI), (Kuching and Tawau) and bad purity of rainfall index (BPRI), (Kota Kinabalu and Bintulu). From the study, it can be stipulated that the chemical composition of rainwater in the study area was attributable to the local activities.

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Environmental Potential Identification on the Example of the Nízký Jeseník Highlands

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201462051095 ◽

2014 ◽

Vol 62 (5) ◽

pp. 1095-1102 ◽

Cited By ~ 2

Author(s):

Aleš Ruda

Keyword(s):

Decision Making ◽

Local Communities ◽

Status Quo ◽

Data Set ◽

Precise Information ◽

Adverse Impacts ◽

Long Time ◽

Quality Of Living ◽

Landscape Attributes

Human activities have a variety of impacts on the environment and local communities as well. Many adverse impacts on landscape have appeared for example in context of tourism development which was considered as an environmentally friendly industry for a long time. That is why it is necessary to find out limits to maintain the environment as well as tourism, because as it turns out in status quo it does not work as it should do. Regions with damaged environment lose its value for the quality of living and the landscape is under the uncontrolled load which burdens the environment. On the level of municipality planning it is important to have precise information for decision making. In the scope of this a specific environmental area value (SEAV) was proposed in selected municipalities in the Nízký Jeseník Highlands as an evidence of landscape fragility, were the increasing interest of tourism has risen up. SEAV calculation is based on scoring municipalities within defined criteria reflecting partial landscape attributes. Proposed data set was evaluated according to ranking decision making method.

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Perbadingan Estimasi Curah Hujan MRR dan TRMM 3B42 Sebagai Input Model Hidrologi HBV Studi Kasus DAS Bedadung

Rekayasa Sipil ◽

10.21776/ub.rekayasasipil.2020.014.02.5 ◽

2020 ◽

Vol 14 (2) ◽

pp. 112-119

Author(s):

Muhamad Zulvi Alhamda ◽

◽

Entin Hidayah ◽

Wiwik Yunarni ◽

◽

...

Keyword(s):

Hydrological Modeling ◽

Temporal Distribution ◽

Rain Gauge ◽

Data Input ◽

Mean Error ◽

Input Model ◽

Rain Data ◽

Trmm 3B42 ◽

Better Than

The limitations of spatial and temporal distribution of rain gauge networks causes inaccuracies in prediction of hydrological modeling. The availability of satellite rain data products is a potential to overcome this limitation. This studies objective is to compare the quality of rain data from the recording of the Manual Rainfall Recorder (MRR) with satellite data TRMM B342 which is entered in the HBV hydrological modeling. Calibration results shows that HBV modeling performance with MRR rain data input is better than TRMM. R2 and NSE values from MRR rain data input were 0.7153 and 0.7133 respectively with a mean error of 89 (mm / year). While the R2 and NSE values of the TRMM B342 satellite rain data input were 0.57 and 0.55 with a mean error of 305 (mm / year), respectively.

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A survey for occultation astrometry of main belt: expected astrometric performances

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038190 ◽

2020 ◽

Vol 641 ◽

pp. A81

Author(s):

J. F. Ferreira ◽

P. Tanga ◽

P. Machado ◽

E. Corsaro

Keyword(s):

Limiting Factor ◽

Data Set ◽

Acceptable Range ◽

Wide Range ◽

Long Time ◽

Spin Properties ◽

Under Construction ◽

Source Of Error ◽

Homogeneous Data

Context. Occultations of stars by asteroids are an efficient method to study the properties of minor bodies, and can be exploited as tools to derive very precise asteroid astrometry relative to the target star. With the availability of stellar astrometry thanks to the ESA mission Gaia, the frequency of good predictions and the quality of the astrometry have been strongly enhanced. Aims. Our goal is to evaluate the astrometric performance of a systematic exploitation of stellar occultations, with a homogeneous data set and a given instrument setup. As a reference instrument, we adopt the example of a robotic 50 cm telescope, which is under construction at the Observatoire de la Côte d’Azur. We focus in particular on single-chord occultations. Methods. We created a data set of simulated light curves, that are modelled by a Bayesian approach. To build the final statistics, we considered a list of predicted events over a long time span, and stellar astrometry from Gaia data release 2. Results. We derive an acceptable range of observability of the events, with clear indications of the expected errors in terms of timing uncertainties. By converting the distribution of such errors to astrometric uncertainties, we show that the precision on a single chord can reach levels equivalent to the performance of Gaia (sub-milli-arcseconds). The errors on the asteroid position are dominated by the uncertainty on the position of the occultation chord with respect to the barycentre of the object. Conclusions. The limiting factor in the use of occultation astrometry is not the light curve uncertainty, but our knowledge of the asteroid's shape and size. This conclusion is valid in a wide range of flux drops and magnitudes of the occulted star. The currently increasing knowledge of the shape, spin properties, and size, must be used to mitigate this source of error.

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Tingkat Pemahaman Kompetensi Guru Pada Mahasiswa Pendidikan Geografi Sebagai Calon Guru Geografi

JURNAL SERAMBI ILMU ◽

10.32672/si.v21i1.1880 ◽

2020 ◽

Vol 21 (1) ◽

pp. 102-117

Author(s):

Novia Zalmita ◽

Muhajirah Muhajirah ◽

Abdul Wahab Abdi

Keyword(s):

Prospective Teachers ◽

Prospective Teacher ◽

Quantitative Description ◽

Population Data ◽

Geography Education ◽

Teacher Competence ◽

Education Department ◽

Long Time

One that influences human resource indicators is education. The teacher is a profession as a job of academic specialization in a relatively long time in college. Understanding related to teacher competence is very important to have by a prospective teacher because it can affect the quality of performance as a professional teacher. The teacher's competence is known as pedagogic, professional, social and personality competencies. The issue in this study is how the competency of the teacher of the Department of Geography Education FKIP Unsyiah as a prospective teacher of geography? The purpose of this study was to determine the competence of teachers in the Department of Geography Education FKIP Unsyiah as prospective geography teachers. Quantitative description approach is used in this study to find answers to the issue. The population in this study were students of the Department of Geography Education FKIP Unsyiah class of 2015 and 2016 who had been declared to have passed the Micro Teaching and Magang Kependidikan 3 course totaling 50 people. Because the population is small and can be reached, the determination of the sample using total sampling techniques so that the sample in this study is the whole population. Data collection is done by distributing test questions to respondents. The data was analyzed using the descriptive statistics percentage formula. The results of the study indicate that the level of teacher competence of Geography Education Department students as prospective teachers is in the moderate category, namely as many as 22 respondents (44%). A total of 12 respondents (24%) were in the high category, 15 respondents (30%) were in the low category and 1 respondent (2%) were in the very low category.

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Electrical Damage Due to Low Energy Plasma Processing of GaAs Structures

MRS Proceedings ◽

10.1557/proc-223-209 ◽

1991 ◽

Vol 223 ◽

Author(s):

Hans P. Zappe ◽

Gudrun Kaufel

Keyword(s):

Chemical Processes ◽

Low Energy ◽

Electrical Behavior ◽

Rapid Thermal Anneal ◽

High Temperature Anneal ◽

Significant Damage ◽

Low Energies ◽

Long Time ◽

Physical Plasma

ABSTRACTThe effect of numerous plasma reative ion etch and physical milling processes on the electrical behavior of GaAs bulk substrates has been investigated by means of electric microwave absorption. It was seen that plasma treatments at quite low energies may significantly affect the electrical quality of the etched semiconductor. Predominantly physical plasma etchants (Ar) were seen to create significant damage at very low energies. Chemical processes (involving Cl or F), while somewhat less pernicious, also gave rise to electrical substrate damage, the effect greater for hydrogenic ambients. Whereas rapid thermal anneal treatments tend to worsen the electrical integrity, some substrates respond positively to long-time high temperature anneal steps.

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PEMBENAHAN TERHADAP LEMBAGA PEMASYARAKATAN DAPAT MENIADAKAN OPSI HUKUMAN MATI BAGI NARAPIDANA DI INDONESIA (THE IMPROVEMENT OF QUALITY OF PENITENTIARY CAN ELIMINATE THE DEATH PENALTY OPTIONS OF CONVICTED CRIMINALS IN INDONESIA)

Yuriska : Jurnal Ilmiah Hukum ◽

10.24903/yrs.v10i2.356 ◽

2020 ◽

Vol 10 (2) ◽

pp. 175

Author(s):

Nomensen Freddy Siahaan

Keyword(s):

Death Penalty ◽

Deterrent Effect ◽

Criminal Cases ◽

Psychological Burden ◽

The Real ◽

The Public ◽

Good Citizen ◽

The People ◽

Long Time

After a long time was not heard to the public area, lately death penalty toward the criminal cases that classified as extraordinary crime are appear. The author discovers electronic article about the execution of the death penalty which is the prosecutor prepares to execute death penalty toward the drugs dealer. The president of Republic of Indonesia stated that it is necessary to give a deterrent effect to the convicted criminal and keep the morality of Indonesian teenagers. According to my opinion, the author argues that it will be better and wiser if we discuss about renovating all of the Penitentiary in Indonesia than debating whether death penalty could be done in Indonesia or not, because it will be displeasure many parties, death penalty infringed the human rights of the convicted criminals and cause psychological burden to them, families, the executor of the death penalty, and other parties. Because if we have to improve the quality of the Penitentiary, if the function of Penitentiary for fostering moralily has been optimal or properly enough to the convicted criminals, Indonesia will be no longer need the death penalty option as sanction to the convicted crimanals including for the extraordinary crime (especially for drugs trafficking in our country). Penitentiary is one of the public services which aims for fostering the people that initially have bad habits (commited to the crime), so that they will have the awareness to change their bad attitude into the be better ones, will not harm others, and positively contributed to the society. Already Penitentiary’s conditions should be designed in such a way and as good as possible, so that the inmates feels like at their own home (like having a second home after his own home), and feel humaner to spend their days in the Penitentiary. The author believes that if the Penitentiary has been improved and optimized its function well, then the real purpose of Penitentiary will definitely achieved. As stated in Law Number 12 Year 1995 regarding to Penitentiary Article 2 which states "sanction system are organized in order to fostering the convicted criminals in order to be the real man, aware of their fault, improve themselves, and not to repeat the criminal act so that they can be friendly received by the community, can actively participated in the development of our country, and can socialize themselves as good citizen."Article 3 on this regulation also intensifies the function of Penitentiary "the function of Penitentiary is to prepare convicted criminals to be able to properly integrated to the society, so they can be accepted again as members of the public who are free and responsible ones."

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