Study of Seasonal Surface Refractivity over North-Central Nigeria

Tropospheric radio wave signals experience loss due to multipath effect, scattering and other forms of attenuation through the atmospheric medium, primarily due to variations in weather conditions with time. The knowledge of surface refractivity profile is important for optimal planning of Very High Frequency/Ultra High Frequency (VHF/UHF) terrestrial radio links in a region. The study of surface refractivity (Ns) over the North-Central Nigeria was carried out using meteorological data from seven locations in North-Central zone of Nigeria. The seasonal variations of Ns were also derived using the monthly summaries of surface data obtained from Nigerian Meteorological Agency (NIMET) over seven stations of Abuja, Lafia, Lokoja, Makurdi, Jos, Minna and Ilorin between 2005 and 2010.The results indicated that the monthly averages of radio refractivity during the rainy season months (April to October) are greater than the Ns values during the dry season months (November to March) for all the locations throughout the years of the study. The computed of mean monthly Ns over all the seven stations in the first 1 km above the ground level is 348 N-units, which gives mean refractivity gradient (dN/dh) of -49 N/k, these shows that the region is characterised by low scale super-refraction. The mean k-factor over the entire region in the first 1 km above the ground level is 1.4; the mean Field Strength Variability (FSV) in first 1 km of height in the region was calculated to be 14 dB. The mean Radio Horizon distance within 1 km height for a transmitter height of 100 m over the stations is 42 km. The results provide useful information needed by radio engineers to set up new terrestrial radio propagation links or to improve on the existing ones especially at VHF, UHF in the North-Central region of Nigeria, as recommended by International Telecommunication Union Recommendations (ITU-R P.453, 2013), which observed the need for local reference data on refractivity and refractivity gradients all over the world.

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ECOLOGICAL CHANGE AND HEALTH SECURITY IN NORTH CENTRAL REGION OF NIGERIA

10.51739/1925375666.v1i1.671871547 ◽

2020 ◽

pp. 15-21

Keyword(s):

Central Zone ◽

Ecological Change ◽

Security Issue ◽

Health Security ◽

North Central ◽

Social Challenges ◽

Security Issues ◽

The North ◽

The People ◽

Health Related

The change in our ecosystem today has creates a lot social challenges. Climate change which is one of the major causes of ecological change is attributed to both the nature and human causes. The issue has resulted in many soft security issues such as health related security issue, food security issue and socio-economic issue. This study examines how ecological change has affected health security of the people in the study area. The study use a sample of three states in the North central zone of Nigeria. The study uses an observation of 385 and the data collected were analyses using Kendell tau test of concordance. The study has found that ecological changes have significant effect on health security in the study area. The study notes that ecological change increase vulnerability to diseases such as malaria, typhoid and zoonosis. These happening thus creates health related issues in the affected areas. On the basis of the finding, it is recommended people in the affect areas should need to be health cautious by treating their drinking water and using anti-mosquitos nets and to equally avoid contact with unfamiliar animals. Keywords: Ecological change, health security and test of concordance

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Statistical Modelling Of HIV/Aids Epidemic In The North Central Zone Of Nigeria

The Internet Journal of Infectious Diseases ◽

10.5580/6a6 ◽

2008 ◽

Vol 6 (2) ◽

Keyword(s):

Central Zone ◽

Statistical Modelling ◽

North Central ◽

Aids Epidemic ◽

The North ◽

Hiv Aids

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The University of South Alabama Mesonet and Coastal Observing System: A Technical and Statistical Overview

Journal of Atmospheric and Oceanic Technology ◽

10.1175/2010jtecha1376.1 ◽

2010 ◽

Vol 27 (9) ◽

pp. 1417-1439 ◽

Cited By ~ 8

Author(s):

Sytske K. Kimball ◽

Madhuri S. Mulekar ◽

Shailer Cummings ◽

Jack Stamates

Keyword(s):

Weather Forecasting ◽

Meteorological Data ◽

Future Research ◽

Sensor Failure ◽

North Central ◽

The North ◽

System A ◽

The University ◽

Mexico Coast ◽

Good Agreement

Abstract The University of South Alabama Mesonet consists of 26 sites across the north-central Gulf of Mexico coast. Although the original purpose of the mesonet was monitoring landfalling tropical systems, meteorological data are collected and disseminated every 5 min year-round to serve a multitude of purposes, including weather forecasting, education, and research. In this paper a statistical analysis and like-sensor comparison demonstrates that variables, measured by different sensor types or by sensors at different heights, correlate well. The benefits of sensor redundancy are twofold, offering 1) backup sensors in the case of sensor failure during severe weather and 2) the ability to perform a large number of internal consistency checks for quality control purposes. An oceanographic compliment to the University of South Alabama Mesonet system, which was deployed by NOAA’s Atlantic Oceanographic and Meteorological Laboratory (AOML) to measure surface waves and ocean currents in an area south of Mobile, Alabama, is described. A preliminary comparison of mesonet wind data and ocean wave data show good agreement, offering promising opportunities for future research.

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Molecular Analysis of Mycobacterium tuberculosis Isolated in the North Central Zone of Nigeria

Journal of Epidemiology and Global Health ◽

10.2991/jegh.k.191015.001 ◽

2019 ◽

Vol 9 (4) ◽

pp. 259 ◽

Cited By ~ 1

Author(s):

Benjamin David Thumamo Pokam ◽

Dorothy Yeboah-Manu ◽

Lovett Lawson ◽

Prisca Wabo Guemdjom ◽

Ruth Okonu ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Molecular Analysis ◽

Central Zone ◽

North Central ◽

The North

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Spatial and temporal variations of rainy days and mean daily rainfall intensity in northern Nigeria.

MAUSAM ◽

10.54302/mausam.v44i1.3791 ◽

2021 ◽

Vol 44 (1) ◽

pp. 85-92

Author(s):

E. O. OLADIPO ◽

S. SALAHU

Keyword(s):

Rainfall Intensity ◽

Daily Rainfall ◽

Temporal Variations ◽

Spatial And Temporal Variations ◽

Northern Nigeria ◽

Rainfall Trend ◽

North Central ◽

The North ◽

The Mean ◽

Rainy Days

The spatial and temporal variations of rainy Gays arid daily rainfall intensity for northern Nigeria for using 54 years data are analysed, The extent and nature of non-random changes, such as trend and fluctuations are Investigated. In general, both, the rainy day frequency and mean daily rainfall intensity decreases northwards except for localized orographic effect in the north central Part of the region. There is statistical evidence or decreasing trend in the, number of rainy days over the period of study, but the trend analysis showed no significance or the mean daily rainfall intensity. This suggests that the recent decreasing rainfall trend In the region particularly In the Sahellan zone, In the result of decrease In the frequency of rainy days and not due to any significant change In the rainfall intensity.

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An outbreak of Aspergillus species in response to environmental conditions in Serbia

Pesticidi i fitomedicina ◽

10.2298/pif1303167l ◽

2013 ◽

Vol 28 (3) ◽

pp. 167-179 ◽

Cited By ~ 24

Author(s):

Jelena Levic ◽

Snezana Gosic-Dondo ◽

Dragica Ivanovic ◽

Slavica Stankovic ◽

Vesna Krnjaja ◽

...

Keyword(s):

Ostrinia Nubilalis ◽

High Frequency ◽

European Corn Borer ◽

Weather Conditions ◽

Very High Frequency ◽

Crop Species ◽

Corn Borer ◽

The Past ◽

Maize Grain ◽

Very High

The frequency and incidence of A. flavus and A. niger on barley, maize, soybean, sunflower and wheat grain, the abundance of European corn borer (Ostrinia nubilalis) moths and their interaction depending on weather conditions in the 2008-2012 period were studied. Under the agroecological conditions of Serbia, the species A. niger is more frequent than A. flavus, and concerning the crop species, its frequency is highest in kernels of sunflower, than soybean, maize, barley and wheat. A. flavus was extremely dominant on all plant species in 2012 regarding its frequency: 100% on soybean, 95.3% on maize, 65.2% on barley, 57.1% on sunflower and 45.8% on wheat. Furthermore, the incidence of A. flavus was higher in 2012 than in previous years. The uncommonly high frequency and incidence of A. flavus infestation of maize grain in 2012 were caused by extremely stressful agrometeorological conditions, high temperatures and drought over the period from flowering to waxy maturity of maize. The precipitation factor (Pf = precipitation sum / average monthly temperature) showed that 2012 was extremely arid in June (Pf = 0.57), July (Pf = 1.45), August (Pf = 0.15) and September (Pf = 1.42). European corn borer (ECB) was a second factor causing intensive occurrence of A. flavus on maize grain in 2012. The maximum flight of ECB moths was recorded as early as in July (5,149) and, as a result of this, high damage and numerous injuries were detected at harvest. Those injuries were covered by visible olive-green powdery colonies typical of A. flavus. In the chronology of A. flavus occurrence, these are the first data on its very high frequency and incidence under the agroecological conditions of Serbia. As intensive infections with A. flavus were rare in the past 50 years, the level of aflatoxins in maize grain was low.

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SUMMER TEMPERATURES OF CRYOSOLIC SOILS IN THE NORTH-CENTRAL KEEWATIN, N.W.T.

Canadian Journal of Soil Science ◽

10.4141/cjss80-034 ◽

1980 ◽

Vol 60 (2) ◽

pp. 311-327 ◽

Cited By ~ 8

Author(s):

CHARLES TARNOCAI

Keyword(s):

Soil Temperature ◽

Slope Position ◽

North Central ◽

Soil Material ◽

The North ◽

Soil Temperatures ◽

Summer Temperatures ◽

The Mean

Soil temperatures were measured at six depths within 1 m of the surface on 10 Cryosolic soils in the north-central Keewatin area during the summer of 1976. The mean soil temperatures during the study period varied between 1.7 °C and 8.2 °C at a depth of 20 cm and −0.2 °C and 6.0 °C at a depth of 50 cm. The maximum and minimum soil temperatures at a depth of 20 cm ranged from 4.4 °C to 13.9 °C and from −0.6°C to 3.9 °C, respectively, while those at a depth of 50 cm ranged from −0.2 °C to 6.7 °C and from −1.1 °C to 2.2 °C, respectively. During the study period a freeze-back of 30 cm or more occurred from the permafrost on several sites. Soil temperatures were markedly higher where the soil material and vegetation were disturbed. The effects of drainage, soil materials, aspect, slope position, vegetation and peat cover on the soil temperature are discussed.

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Pattern of oral cancers in the North Central zone of Nigeria

African Journal of Oral Health ◽

10.4314/ajoh.v1i1.31305 ◽

2004 ◽

Vol 1 (1) ◽

Cited By ~ 1

Author(s):

EC Otoh ◽

NW Johnson ◽

BM Mandong ◽

IS Danfillo

Keyword(s):

Central Zone ◽

North Central ◽

Oral Cancers ◽

The North

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Assessing the climatic potential for epizootics of the gypsy moth fungal pathogen Entomophaga maimaiga in the North Central United States

Canadian Journal of Forest Research ◽

10.1139/x09-117 ◽

2009 ◽

Vol 39 (10) ◽

pp. 1958-1970 ◽

Cited By ~ 10

Author(s):

Nathan W. Siegert ◽

Deborah G. McCullough ◽

Robert C. Venette ◽

Ann E. Hajek ◽

Jeffrey A. Andresen

Keyword(s):

United States ◽

Gypsy Moth ◽

Fungal Pathogen ◽

Weather Conditions ◽

Eastern United States ◽

Spring Temperature ◽

North Central ◽

The North ◽

Temperature And Precipitation ◽

Entomophaga Maimaiga

The fungal pathogen Entomophaga maimaiga Humber, Shimazu et Soper has become an important biocontrol for gypsy moth ( Lymantria dispar (L.)) in the northeastern United States and is commonly introduced into new areas with established gypsy moth populations. Germination of the fungus is dependent on spring temperature and moisture, but specific conditions associated with epizootics have not been determined. Whether E. maimaiga will be as effective in other regions that experience different weather conditions is not yet known. We examined similarity of weather conditions associated with 16 documented E. maimaiga epizootics with conditions at 1351 North American locations using the climate-matching software CLIMEX. Based on CLIMEX’s overall index of climatic similarity, long-term annual climatic patterns across much of the eastern United States were 60%–80% similar to the conditions associated with epizootics. Monthly weather records from 1971 to 2000 in nine North Central states were examined to compare precipitation and temperature with conditions observed during epizootics. Based on climatic averages identified with the documented epizootics, temperature and precipitation conditions in Illinois, Indiana, Iowa, Kentucky, Missouri, and Ohio were more conducive for epizootics than conditions in Minnesota, Wisconsin, and Michigan, which were likely to support E. maimaiga epizootics in fewer than 6 of the 30 years considered.

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