bluuebunny/crossref_metadata_2025 huggingface dataset:
Separabilidad espectral de cultivos agrícolas con Imágenes Landsat TM
Authors: Majarrez-Domínguez Carlos , Pinedo Álvarez Dr. Carmelo , Vélez-Sánchez Verín Dra. Cristina Elizabeth , Pinedo Álvarez Dr. Alfredo
Published: February 2022

Los sensores remotos de diversas plataformas satelitales representan una herramienta para apoyar la toma de decisiones; la necesidad de contar con información ordenada y confiable sobre fenómenos de producción, establecimiento y manejo de áreas agrícolas motivó la ejecución de esta investigación que tuvo como objetivo analizar la separabilidad espectral de cultivos agrícolas del módulo 9 en el municipio de Meoqui, Chihuahua. Se utilizó el plano digital vectorizado del Distrito de Riego 005 y se georreferenció a través de puntos de control terrestre localizados mediante sistemas de posicionamiento global. Los puntos de control terrestre fueron ubicados en las imágenes compuestas de Landsat TM y en las cartas topográficas escala 1:50,000. En las parcelas bajo muestreo se realizó el análisis de separabilidad espectral de los cultivos de chile, nogal, cebolla, sandía y alfalfa, utilizando ventanas de 3x3 pixeles para colectar valores de reflectancia para cada banda de Landsat TM. Estadísticas descriptivas apoyaron la discriminación espectral. Se obtuvo un plano cartográfico digital del Módulo 9 del Distrito de Riego 005, orientado y georreferenciado con buen nivel de precisión. El análisis espectral de los cinco cultivos evaluados concentra la mayor parte de la información en un rango de 45 ND’s (números digitales), con valores mínimos de 80 ND’s y máximos de 125 ND’s en las bandas visibles del espectro. La banda 3 mostró mayor capacidad para separar las firmas espectrales en comparación al resto de las bandas. Para el análisis simultáneo de los cinco cultivos y la generación de mapas a partir de clasificaciones exitosas, se sugiere utilizar las bandas 1, 2, 3 y 7, debido a que ofrecen mayor información, ya que ubican en forma precisa y sin confusión las distintas fir-mas espectrales de los cultivos.

DOI: https://doi.org/10.54167/tecnociencia.v1i2.51
Characterization of In Vitro Antioxidant Potential of Xanthosoma Violaceum Schott (Araceae) by Different Assay Methods
Authors: Nishanthini A. , Mohan V.
Published: February 2022

The antioxidant activity of Xanthosoma violaceum Schott corm extract was assayed through in vitro models such as DPPH, Hydroxyl, Superoxide and ABTS radical cation scavenging and reducing power. The total phenolics and flavonoids methanol extract were found to be 0.37g100-1 and 0.48g100-1 respectively. The methanol extract of Xanthosoma violaceum corm showed potent of in vitro antioxidant activities. The maximum inhibitory concentration (IC50) in all models viz Superoxide, ABTS, DPPH and Hydroxyl radical were found to be 73.84, 36.65, 24.56 and 21.04 µg/ml., respectively at 1mg/ml concentration. The finding of the present study confirmed the presence of total phenolics, flavonoids and possess in vitro antioxidant activity.
Genomic evaluation of binary traits in dairy cattle by considering genotype × environment interactions
Authors: Eteqadi Bahareh , Rafat Seyed A. , Alijani Sadegh , König Sven , Bohlouli Mehdi
Published: February 2022

Aim of study: To assess genotype by environment (G×E) interaction via single- and multi-trait animal models for binary traits in dairy cattle. 
Area of study: University of Tabriz, Tabriz, Iran.
Material and methods: Phenotypic and genomic data were simulated considering a binary trait in four environments as different correlated traits. Heritabilities of 0.05, 0.10, 0.15, and 0.20 were considered to mimic the genetic variation of the binary trait in different environments. Eight scenarios resulted from combining the number of QTLs (60 or 300), LD level (high or low), and incidence of the binary trait (10% or 30%) were simulated to compare the accuracy of predictions. For all scenarios, 1667 markers per chromosome (depicting a 50K SNP chip) were randomly spaced over 30 chromosomes. Multi-trait animal models were applied to take account of G×E interaction and to predict the genomic breeding value in different environments. Prediction accuracies obtained from the single- and multi-trait animal models were compared.
Main results: In the models with G×E interaction, the largest accuracy of 0.401 was obtained in high LD scenario with 60 QTLs, and incidence of 30% for the fourth environment. The lowest accuracy of 0.190 was achieved in low LD scenario with 300 QTLs and incidence of 10% for the first environment.
Research highlights: Genomic selection with high prediction accuracy can be possible by considering the G×E interaction during the genetic improvement programs in dairy cattle.
Movement of premonsoon squall lines over Gangetic West Bengal as observed bh radar at Dum Dum Airport
Authors: DE A. C.
Published: February 2022

Movement of 44 squall lines over the Gangetic West Bengal during the premonsoon season (March - May) if 1959-1961 as observed by a powerfull 3-cm Japanese Radar at Dum Dum Airport (Calcutta) has been studied. It has been found that the movement of the squall lines cannot be explained by the upper wind alone. The direction of movement is generally within 90 degree to the right of the wind. It has been suggessted that the well-known Regenerative Drift Process is responsible for such high speed of movement of the squall lines.
Solar control of the annual variation of the quiet-day horizontal component of geomagnetic force
Authors: YACOB A.
Published: February 2022

The predominant component of the mean annual variation of Hq for Alibag for the period 1904 to 1958 is the 12 monthly component. For Huancayo, for the period 1923-1946, it is the 6 monthly component which is found to be predominant. This difference is accounted for by considering the annual variation of Hq as a consequence of the superposition of Sq on Hq. Huancayo being much closer to the geomagnetic as well as geographic equators than Alibag, the variation in the feature for Huancayo, while for Alibag this variation will largely be annual feature.

While the amplitudes of the 12 monthly components of individual years show very little correspondence with sunspot numbers, the amplitudes of the 6 monthly components show appreciable corrospondence with sunspot numbers. To explain this feature the variation in the heliographic latitude of the earth, in the course of the year, coupled with emanation of shortwave radiation of high ionization potential from solar active regions, which are known to form two average belts 10-15 deg. N and S of the solar equator, is suggested in the preference to the incidence of disturbance on Hq, since the dates of maxima of the 6 monthly component for years of high sunspot numbers are found to be closer to the equinoxial months.
A study of Cyclonicity in relation to rainfall over Indian region
Authors: TRIPATHI N.
Published: February 2022

Based on examination of daily synoptic charts for the ten year period, 1944-1953, a study has been made of days on which centre of a cyclonic system lay in each five degree square in the region covering India and neighbourhood. Monthly charts have been prepared, showing frequency of occurrence of cyclonicity over each such zone and also its progressive behaviour in regard to its persistence or future movement. A rainy day, defined as one having rainfall of 10cents or more, is found to be related significantly to cyclonicity over a given area except durung hot weather period, March to May.
Downward transport of ice forming Aerosols from the stratosphere
Authors: SATYAMURTY P. , MURTY BH. V. RAMANA
Published: February 2022

The possibility of association of the observed increases at the ground in the concentration of the ice-forming aerosols with the phenomenon of the stratospheric mass transport downwards has been investigated. The study, which is qualitative in nature, has indicated that transport downwards from the stratosphere of ice-forming aerosols is a strong possibility. It also suggested, by implication, that the stratosphere could be rich in ice nuclei.
A note on the movement of storms and depressions in the Bay of Bengal during October and November
Authors: RAMANATHAN A. S.
Published: February 2022

The October-November storms and depressions of the period 1950-1968 in the Bay of Bengal have been classified in to three district classes based on their tracks. Certain district synoptic features associated with each of these classes as observed at the time of formation of the depression or storm in the Bay, in extended charts covering the Indian region and West Pacific Ocean west of 150' E have been listed and their validity in individual cases examined.
Annular cloud formations over the Indian land area
Authors: PISHAROTY P. R.
Published: February 2022

From films of dally digital cloud cover mosaics from ESSA satellites obtained from the US Weather Bureau, enlarged "photographic prints were made for a study of cloud systems and their structure over the Indian Ocean and adjoining areas.
Satellite-determined cloudiness in the tropics in relation to large scale flow patterns Pt. II. Case-studies of developments outside the Indian southwest monsoon region
Authors: RAMASWAMY C.
Published: February 2022

The paper contains the results of 4 case studies of satellite observations of clouds especially over se-areas in the tropics, in relation to monthly mean large-scale flow-patterns during the period June to September 1965.  Three of the case-studies relate to the southern hemisphere in the region of westerlies and one to the northern hemisphere in the region of easterlies.  These studies have shown that there are close associations between satellite-determined cloudiness and certain specifie types of flow patterns at the 700, 500 and 300-mb levels. The observed quasi-empirical relationships would be useful to the forecaster in his day-to-day predictions, especially for sea areas wherefrom he may not have any cloud or rainfall observations at the time of forecasting.
Some aspects of upper tropospheric outflow from severe cyclonic storms in the Bay of Bengal and Arabian Sea as revealed in satellite pictures
Authors: RAMANATHAN A. S.
Published: February 2022

In this paper a study has been made of the essential features of the cirrus canopy .of twenty cases of severe cyclonic storms in the Bay of Bengal and Arabian Sea as revealed in satellite pictures received at Bombay during the period 1966.1969. Making use of a simple model proposed by Merrit and Wexler, the nature of the distribution of the radial and tangential components of outflow in the different quadrants is examined in each case and its relation to the direction of motion of the storm is discussed.
Monsoon depression as seen in satellite pictures
Authors: SRINIVASAN V. , RAMAN S. , RAMAKRISHNAN A. R.
Published: February 2022

Satellite cloud pictures for the periods of monsoon depressions, from formative stage to dissipative stage, during July to September, 1967-69 were examined. Five broad types of cloud patterns could be identified in these pictures and they have been empirically correlated with the observed synoptic and upper air features. The pattern of clouding readily gives an indication of the intensity of the monsoon disturbance as well as its centre. The salient features of the five cloud patterns and the associated synoptic and upper air features are briefly discussed. The principal area of heavy rains is identified from the cloud patterns.
Centres of monsoon depressions as seen in satellite pictures
Authors: SHARMA M. C. , SRINIVASAN V.
Published: February 2022

In satellite pictures of monsoon depressions, the centre of the depression is generally inferred by the curvature of the cumuliform bands in the northern half of the depression field. The positions of the depression centres determined from satellite pictures are found in a majority of cases located southwest of the centre on the sea level isobaric chart. The shear winds between 850 and 500-mb levels do not define any closed circulation whose centre could correspond to the depression centre derived from satellite pictures. The satellite determined centre appears to be close to the centre of the depression at 700 or 500mb level.. The results are tentative as they are based on very limited observations.
A stacked Yagi antenna for APT reception
Authors: GUPTA J. DAS
Published: February 2022

The paper describes design and construction of an antenna system with two Yagi arrays stacked to have high gain and directivity. The antenna can be rotated both in azimuth and elevation and used to track a weather satellite by remote control using torque drive motors.
Cloud systems associated with western disturbances : A preliminary study
Authors: RAO N. S. BHASKARA , MORAY P. E.
Published: February 2022

During the winter season cloud and precipitation belts are seen to move from west to east over northern India. The cause of these cloud and precipitation systems came to be referred to as 'western disturbances'. In this study the cloud systems have been classified into five broad categories. Typical examples of these cloud patterns and synoptic conditions most commonly associated with each category of cloud systems are presented in this paper.
On the estimation of upper winds from satellite cloud pictures
Authors: RAO N.S. BHASKARA , MAZUMDAR S.
Published: February 2022

The direction of upper tropospheric flow was estimated from the cirrus plumes associated with Cb clouds seen on satellite television pictures. The estimated directions were compared with actual wind directions at the 300 and 200 mb, and also with the directions of the shear between winds at ( a) 700 and 200 mb and { b) 500 and 200 m b. The results of the comparison are presented in this paper.
Vertical temperature distribution of the atmosphere from the Indian (Tropical) radiosonde stations from Nimbus III satellite infra-red spectrometer (SIRS) measurements
Authors: SIVARAMAKRISHNAN M. V. , Rao K. N.
Published: February 2022

Satellite Infrared Spectrometer (SIRS) measurements obtained from Nimbus III offer for the - first time an opportunity to estimate the vertical temperature distribution over the Indian (Tropical) region. The vertical temperature distribution at three Indian R. S. stations (New Delhi, Bombay and Visakhapatnam) on 14 and 15 May 1969 have been calculated from the radiation data taken by SIRS spectrometer in the 15 micron carbon dioxide band, close to these three stations. The calculated values show good agreement upto 100mb.
A study of active monsoon over India using satellite radiation data
Authors: SRINIVASAN V.
Published: February 2022

Tiros VH radiation data in the 8-12 micron channel for the period 5-8 July 1963 has been analysed. This was a period of good monsoon activity in the Peninsula and central India, The I.R. analysis is compared with surface synoptic and upper air charts. The results indicate that the general height of tops of monsoon clouds is about 7.8 km and these clouds presumably do not extend much into the upper tropospheric easterlies. However, in the areas of localised heavy monsoon activity. the clouds extend at least as high as 12 km. The average size of such thick cloud clusters is of the order of 3 to 5 degrees of Lat/Long, across and !n some cases even more.
Radiation climate of New Delhi Part II : Longwave radiation and energy budget
Authors: LETTAU KATHARINA
Published: February 2022

Monthly budgets of long wave short wave, and net radiation, separate for air-space and air-soil interfaces, and also for the atmospheric column, are presented for the years 1964 and 1965 at New Delhi. A combination of direct radiation measurements at Lodi Rd. Observatory, New Delhi evaluations of satellite based scannings of the region, and climatonomical theories (as developed by H. Lettau), yields the monthly budgets of latent and sensible heat. Radiative shortwave heating and longwave cooling rates for the local atmospheric column are summarised for the seasons, resulting in a mean annual net cooling rate of 0. 4°C in both years.

In this climate where the seasonal maximum of precipitation coincides closely with that of. insolation, the moisture budget at the air-soil Interface shows that about 80 per cent of the annual evaporation occurs from July to September In both years. Surface runoff appears to be restricted to the monsoon season and amounts to less than evapotranspiration even in the wettest month. Calculated values of exchangeable soil moisture were about twice as high in 1964 than in 1965 due to the intensive monsoon. The carry-over into the following dry season was considerable. Net moisture import (horizontal advection) into the atmospheric column over New Delhi was more than five times higher during the summer of 1964 than of 1965. The change over from moisture import to moisture export occurs abruptly with the greatest drop during October in both years.

The calculation of a complete energy budget for the soil-air interface shows that due to the great demand of energy for evapotranspiration, monthly means of sensible heatflux, normally directed from the ground into the air during summer, can be reversed resulting in 'psychrometric cooling' of the ground. In 1964, such reversal occurred from July to September, but in 1965 it was weak and restricted to the month of September. Accordingly, the monthly mean surface temperature dropped from June to July by 10°Cin 1964, but only by 60Cin 1965. Flux of sensible heat from and into the soil reaches extremes in December and April, respectively, but turned out to be small in comparison with other constituents of the monthly heat budget.

With the aid of the 'climatonomical' analysis method it is possible to establish quantitatively the constituent terms of the energy budget. For the atmospheric column, however, the energy supplied by advection cannot be separated from the contribution by subsidence. Considering the importance attributed to subsidence for maintaining arid conditions over northwestern India, a supplementary synoptic-aerological analysis of the atmospheric circulation over the region appears to be desirable in order to separate the effects of the two processes in the course of the year.
Heights of cumulonimbus cloud tops over the Brahmaputra valley (Assam): A radar study
Authors: RAY T. K.
Published: February 2022

Recent information, though not very adequate, about cumulonimbus cloud heights are available in India, from post flight reports of civil jet airliners and meteorological reconnaissance flights organised by Air Force. In the present paper, results of radar study of the heights of Ob cloud tops in the Brahmaputra valley, based on hourly radarscope observations, for pre-monsoon and monsoon months of 1967. 1968, 1969 and 1970 have been reported.
On the activity of the Arabian Sea monsoon
Authors: RAMAMURTHI K. M.
Published: February 2022

In connection with the activity of the Arabian Sea monsoon, Ramage's postulate regarding the relationship between the intensity of the heat low over West Pakistan and the monsoon rains was examined and it was found that the heat low does not contribute to the strengthening. If the low level monsoon flow. The effects of monsoon perturbations are found to extend from sea level and are therefore considered directly responsible for strengthening the low level monsoon flow. A method of Identifying the effects of perturbations of active as well as weak Arabian Sea monsoon is postulated. This brought out that active Arabian Sea monsoon is associated with two cyclonic vertices which in the mean are lacated over the Gulf of Cambay (Gujarat low) and the northern parts of east coast 'eastern low' respectively and extend from sea level upwards affecting the wind flow practically throughout the entire troposphere. The reason for the cyclonic circulation associated with the Gujarat low not being obvious in lower tropospheric levels is discussed. The importance .of contribution to northerly meridional flow along the west coast at upper tropospheric levels by the perturbations of strong monsoon is highlighted. The strength of upper level east wind maximum over south Peninsular India is found to be less during strong than in weak monsoon. This goes against the hypothesis regarding the role of release of latent heat in causing the summer time easterly jet. The effects of perturbations of weak Arabian Sea monsoon are found to be just the reverse of those of strong monsoon. Certain aspects of the transformation of airmass over the east Arabian Sea are also discussed.
Forecasting the movement of tropical storms/ depressions in the Indian region by a computer oriented technique using , climatology and persistence
Authors: SIKKA D. R. , SURYANARAYANA R.
Published: February 2022

A computer-oriented technique for forecasting the movement of tropical storms/depressions in the Indian seas, based on half persistence and half climatology has been tested. The climatological components of the forecast is computed by a computer programmer, by scanning the climatological tracks within a predetermined scan, distance from the centre of the storm to be predicted. The method had been tested on independent data for pre-monsoon and post monsoon storms/depressions during 1961-67, and performance of forecasts categorised. The accuracy-of the forecast by the method compares favourably with other operational objective methods in use elsewhere. Probability ellipses of the errors have been constructed. Results of the forecasts based on experimental real time basis during 1968-70 are also discussed.
An objective method of forecasting pre-monsoon thunderstorm dust storm activity over Delhi and neighbourhood
Authors: KUMAR SURENDRA
Published: February 2022

An attempt was made to provide an objective aid for forecasting of thunderstorm/dust storm in pre-monsoon season over Delhi and neighbourhood. Relationships of a number of meteorological parameters to subsequent convective activity were determined and the five parameters which showed the strongest relation ships were combined by graphical correlation techniques to form an objective forecast aid.

The method was tested on independent data and the results were found to be consistent with those obtained on the developmental data.
Independence of rainfall over Indian subcontinent over time scale of less than a month during monsoon season
Authors: MOOLEY D. A. , RAO G. APPA
Published: February 2022

Independence of rainfall during monsoon season at representative Indian stations over time scales of 5, 10, 15, 20 and 25 days has been investigated. Chi-square tests have been applied to test the null hypothesis of independence against the alternative hypothesis of non-Independence or association. The study reveals that, (i) rainfall over time scales of 5 and 10 days is not pair wise independent for consecutive periods but is pair wise independent for (iii) rainfall over all the title scales considered In this study is not tripletwise Independent. The significance of these features for the combination of frequency distributions is discussed.
Extreme wind speeds over India
Authors: HARIHARAAYYAR P. S. , GOYAL S. C.
Published: February 2022

A study of extreme wind speeds in gusts over different parts of India have been made using autographic wind data for 25 stations equipped with Dines pressure tube anemographs. Maps of India have been prepared for return periods of 2,5, 10, 25,  and 100 years, based on these date. These are expected to provide engineers with wind data of different probabilities which will be helpful in designing structures in different parts of the country.
A combined sonde for the measurement of electrical conductivity and potential gradient in the atmosphere
Authors: HUDDAR B. B. , RAO K. R.
Published: February 2022

The paper describes a combined sonde for the simultaneous measurement of the vertical distribution of electrical conductivity and potential gradient in the upper atmosphere during a balloon flight. The data obtained helps in evaluating the third parameter, i.e., air earth conduction current at all levels. Thus all the three main parameters of the atmosphericelectrioity can be measured with a single sonde. A typical sounding taken with the above instrument is also presented.
The severe drought over Tamil Nadu during the retreating monsoon period of 1968 and its associations with anomalies in the upper level flow patterns over the northern hemisphere
Authors: RAMABWAMY C.
Published: February 2022

The mean contours and isotherms over the Indian sub-continent at the 850.mband 300-mb levels and the moisture- content of the air over Tamil Nadu in November 1968 (a month of severe drought in that State) and in November 1966 (a month of fairly good retreating monsoon rainfall over the same area) have been discussed. The daily 700 and 500-mb charts for the Indian sub-continent, the 300 and 200-mb charts for Asia and Europe and the monthly mean 700-mb charts for the northern hemisphere during the same two months have also been studied. It has been shown that, during the drought month, the Subtropical Jet Stream System (STJS) was not only in unusually low latitudes over India but it was also markedly stronger than usual. This abnormality in the STJS was directly or indirectly associated with large-scale anomalies in the upper level flow patterns in the atmosphere over the middle and higher latitudes in the northern hemisphere. The genesis of these anomalies has been traced back step by step as far west as the United States of America.

The anomalous fluctuations of the STJS were indirectly responsible for the cyclonic storms in the Bay of Bengal being 'steered away' from Tamil Nadu and were thus also partly responsible for the drought conditions over Tamil Nadu.

The observed progressive trend of equatorward movement of the STJS along with the polar front jet and a deep cyclonic vortex in the subpolar latitudes in November 1968 has been discussed in relation to the progressive increase in the rainfall deficiency over Tamil Nadu during the Same period. It has been suggested that the parameters utilised in the present study could be tried out in medium range forecasting of rainfall over Tamil Nadu during the retreating monsoon period.
Relationship between evaporation and other , meteorological factors
Authors: RAO K. N. , RAMAN C. R. V. , JAYANTHI S.
Published: February 2022

Using correlation techniques, an assessment is made of the influence exerted by basic meteorological factors in controlling .the evoporative power of air. Linear regression equations are developed for twenty five stations linking pan evaporation with saturation vapour pressure deficit, maximum temperature and mean daily wind speed. Evaporation computed with formulation thus developed compares favourably with actual data.
Objective method of forecasting thunderstorms In winter season over Delhi State
Authors: KUMAR SURENDRA
Published: February 2022

The purpose of this study was to develop an objective aid for forecast1ng of thunderstorms in winter season over Delhi State. Relationship of a number of meteorological parameters to subsequent thunderstorm activity was investigated. The five parameters showing strongest relationship were finally selected and analysis applied to form objective forecast aid. The method was tested on independent data and the results were consistent with those obtained on developmental data.
Trends and quasi-biennial oscillation in the series of cyclonic disturbances over the Indian region
Authors: BHALME H. N.
Published: February 2022

Seasonal and annual freq1leoncies of cyclonic disturbances that occurred over the area extending from Lat, 5 N to 35 N and Long, 50 E to 100 E for the period of 80 years from 1891 to 1970 have been examined by fitting orthogonal polynomials and by power spectrum analysis.

The analyses reveal a significant falling trend in the number of cyclonic disturbances in the SW monsoon season. This fall seems to have began at the start of the present century, Annual cyclonic disturbances show a falling trend after 1940 upto1965 and rise afterwards. The long period oscillation of about 40 years is seen in the SW monsoon and annual number of cyclonic disturbances. There IS also an evidence of q1lasi-biennial oscillation in the number of cyclonic disturbances during SW monsoon season.
Clear air turbulence (CAT) in India and neighbourhood
Authors: GUPTA G. R. , NAYASTHANI M. M. , VERMA R. K.
Published: February 2022

The present study of CAT over India and neighbourhood has been based on the inflight and -post flight reports received and on the debrief reports given by national and international operators during the period January 1966 to December 1969. CAT has been studied in its spatial and vertical distribution on the basis of, 32 available data. The effects of various upper air flow patterns, such as westerly and easterly jets and wind discontinuity etc. Contributing to the occurrence of CAT, have also been studied, An attempt has also been made in this paper towards the detection of favourable conditions for occurrence of CAT. The role of temperature distribution and pools of cold and warm air in the upper air have been discussed, Some typical examples of the phenomenon , have been illustrated.
Sunshine and cloudiness over India
Authors: GANESAN H. R.
Published: February 2022

The relationship between sunshine and cloudiness has been studied, by utilising sunshine and cloudiness data for period 1953-1965 in respect of 20 stations covering the Indian latitudes. Regression analysis has been carried out and regression constants have been derived. The total of 2995 samples from all the stations for the 12 months of the year has yielded as high a correlation factor as 0.87.

The estimated values of bright hours of sunshine agree very favourably with those actually observed. The cloud observations can thus be reliably utilized to supplement the instrumental measurements of sunshine to provide sufficient data for the study of climatology of duration of bright sunshine over India.
A scheme for deriving grid point values from observatory reports for numerical weather prediction
Authors: RAO Y. P. , RAMAMURTI K. S. , SINHA M. C.
Published: February 2022

A mathematical method is developed to calcalate the value of any parameter at a grid-point from its average values over three squares symmetric around the point. The weighting functions are derived from the dimensions of the scanning squares. This procedure takes into account all differentials below the sixth order in a Taylor expansion. Truncation error due to neglect of higher order differentials is assessed. Certain refinements to the weighting functions due to using finite number of observations in scanning squares are introduced. Modification and suppression of small waves are discussed in relation to scan-length, average distance between  observatories and their random distribution. The method was tried on long and short waves by a numerical experiment.
Oceanography of the Arabian Sea during the southwest monsoon season-Part III : Salinity
Authors: SASTRY J. S. , D'SOUZA R. S.
Published: February 2022

The distribution of salinity in the Arabian Sea during the southwest monsoon season is presented through several vertical sections and spatial distribution charts. The vertical salinity structure has been found to be quite complex and shows several maxima and minima upto depths of about 1000 m. An analysis of the water mass characteristics shows that the Arabian Sea high salinity water forms in the northeastern Arabian Sea as a result of excessive evaporation over precipitation and is located between 300 and 500 el/t steric levels. The Persian Gulf and Red Sea Waters have been identified by their salinity maxima occurring above and below the 100 cl/t surface respectively. In addition, it has been found that, in the depth range of 0-1000 m, the Antarctic intermediate water, subtropical subsurface water and the south equatorial water penetrate into the Arabian Sea at different levels and intermingling of these with the Red Sea, Persian Gulf and Arabian Sea high salinity waters give rise to the observed complexities in the vertical salinity structure. A comparison of the curves of potential temperature versus depth, salinity and oxyty in the Somali and Arabian basins with those in the circumpolar regions has shown that the deep and bottom water mass in these basins at depth exceeding 2500 m is of circumpolar origin.
Certain aspects for intensification of tropical storms over Indian Ocean area
Authors: BANSAL R. K. , DATTA R. K.
Published: February 2022

Palmen (1956) gave three climatological and geographical conditions as pre-requisites for the  formation of tropical storms. One of these being that the region of formation of storm should be over sufficiently large sea or ocean area with temperature of the sea surface so high that airmass shifted from the lowest layers of the atmosphere and expanded adiabatically with condensation remains considerably warmer than the surrounding undisturbed atmosphere at least between 500 and 200 mb. The temperature differences for island stations of Port Blair and Minicoy and the coastal stations were studied to test the above hypothesis for Indian area. In general it is found that Palmen's hypothesis holds good over the Bay of Bengal as well as the Arabian Sea.
Nature of the frequency distribution of Indian rainfall : Monsoon and annual
Authors: RAO K. N. , GEORGE C. J. , ABHYANKAR V. P.
Published: February 2022

The frequency distribution of southwest monsoon season and annual rainfall of about 500 rain-recording stations (1901-l960) forming a close and representative network in India was examined by statistical methods. It is seen that Indian rainfall does not differ significantly from normal except in a few small areas. Most of the country, excluding the Western arid and semi-arid areas, has values of coefficient of variation (annual) between 20 to 30 per cent irrespective of the amount of rainfall.
Incidence of droughts in Andhra Pradesh, Tamil Nadu and Mysore
Authors: GEORGE C. J. , RAMASASTRI K. S. , RENTALA G. S.
Published: February 2022

Drought spells in Andhra Pradesh, Tamil Nadu and Mysore during the last 60-65 years are studied by computing the monthly Palmer index values. For computing the index, a detailed hydrologic accounting of the area is carried out for a large number of years using data of rainfall, potential evapotranspiration and water-holding capacity of the soil. Several parrameters are obtained from this accounting and the be are used to compute the 'CAFEC' (Climatically Appropriate For Existing Condition) precipitation of each month of the period. Anomaly of actual rainfall with respect to this 'CAFEC' precipitation is obtained for each month and this is used to compute Palmer index of the month.

Several drought spells occurred in these areas during the period studied. The longest drought spell experienced in each area was: (i) Interior My010re North-70 months (August 1922 to May 1928), (ii) Coastal Andhra Pradesh-57 months (July 1904 to March 1909), (iii) Tamil Nadu-41 months (November 1949 to March 1953), (iv) Rayalaseema 36 months (March 1941 to February 1944), (v) Telangana-35 months (May 1911 to March 1914 and July 1918 to May 1921) and (vi) Interior Mysore South-27 months (December 1948 to February 1951).
Estimates of vertical velocity by numerical and analytical methods -A comparison
Authors: RAO K. V. , RAJAMANI S.
Published: February 2022

Numerical computations with the complete w-equation for quasi-geostrophic adiabatic motion have been made for comparison with earlier computations with a simplified form of w-equation. Also an attempt has been made to check the magnitudes of vertical velocity computed by the simplified w-equation, with the values obtained from Kuo's analytical expression for w. The extent to which there is agreement has been discussed.
Long dry spells of short return periods during southwest monsoon along the Konkan coast
Authors: SINGH GURBACHAN
Published: February 2022

The southwest monsoon strikes the Konkan coast in the first week of the June and withdraws by the first week of October. The period June to September, being not the period of continuous rain, the pulsatory character of the monsoon is a very important feature. Since temporary monsoon breaks cause great anxiety in the country, an attempt has been made to examine how prolonged, on the average, are the monsoon breaks for various return periods, for certain stations along the west coast of India. As Lawrence (1957) after calculating the frequencies of runs of dry days of different lengths for some stations in southern and eastern England using Jenkinson probalility' method found that it does not provide reasonsable estimates of frequencies, the author has analysed the data by the techniques of extreme values statistical analysis. The values of length of runs of dry days during the southwest monsoon for 2, 5, 10 and 25 years return period for Karwar, Marmagoa, Ratnagiri, Bombay (Colaba) and Surat have been found.
Trends of the concentrations of some gaseous pollutants in Bombay
Authors: ZUTSHI P. K. , MAHADEVAN T. N. , BANERJEE TAPOTI
Published: February 2022

The monthly average concentrations of sulphur dioxide, nitrogen oxides, total oxidants and ammonia over the years 1968-1971, at the BARC site, Bombay are presented. The figures indicate an overall tendency of increasing concentrations year after year.

The sulphur dioxide concentrations as measured by the lead peroxide method at several sites in Greater Bombay over the part few months as monthly averages are also presented. These figures indicate widespread sulphur dioxide pollution with a few pockets with relatively higher concentrations.
Prognosis by four-layer quasi-geostrophic model
Authors: MUKERJI T. K. , DATTA R. K.
Published: February 2022

Results of experiments in forecasting the heights of 850, 700, 500 and 300-mb levels 24 hours in advance, using a four-layer quasi-geostrophic model are presented here. As a first step, the vertical velocities of surface and 200-mb level have been assumed to be zero. The static stability parameter is computed from known values of temperatures and pressures. The area covered for the study has been made large, so as to avoid the effect of constant values at the boundaries on the forecast for Indian areas.
Conditions for normal summer monsoon rainfall and causes of droughts over western India
Authors: RAO Y. P. , DESAI B. N.
Published: February 2022

Model for the Arabian Sea summer monsoon proposed by Ramage ( 1969) and his conclusions about drought of 1899 in western India have been discussed. The heat-low over Pakistan and the air from across the equator drawn north and northeastwards which helps development of the trough over the Gangetic valley under the influence of the topographical features of the subcontinent, are considered the primary causes responsible for the setting up of monsoon circulation upto about 600 mb and the latent heat of condensation would not appear to play any significant role in the same.
An empirical method for estimation of evaporation from free surface of water
Authors: REDDY S. JEEV ANANDA , RAO K. RAMA
Published: February 2022

A new empirical method has been developed for computing the pan evaporation (E) using solar radiation intensities as obtained from the formulae of Reddy (1971) for total and net radiation intensities, The  results obtained are in good agreement with observed value, which are presented. The formulae of Reddy (1971) for total (Rt) and nf,t (En) radiation intensities are extended to hill stations and are discussed. Curves suitable for direct reading of Rt. Rn and E values to the required accuracy are also presented.
Climatic factors influencing agriculture in the low rainfall tract of Bellary in Mysore State
Authors: RAMANATH B. , RAO D. HAYAVADANA , RAO S. B. PRABHANJAN , VERMA BALVIR
Published: February 2022

The general climatic features of Bellary based mainly on the data recorded at the Soil Conservation Research Farm for the period 1956.69 are presented. The short period rai11fall data of the farm is compared with 100-year rainfall record of the Bellary Observatory regarding amounts, distribution and monthly probabilities of occurrence of rain of specific amount.
Heights of cumulonimbus cloud tops over the Deccan Plateau and adjoining plains of Andhra Pradesh and east Maharashtra : A preliminary radar study
Authors: THOMAS S. I. T.
Published: February 2022

A radar study of heights of tops of cumulonimbus clouds over the Deccan Plateau and adjoining plains of Andhra Pradesh and east Maharashtra is presented in this paper. The study is based on all routine and non - routine weather radar observations taken and recorded by the Meteorological Office, Begumpet Airport, Hyderabad during a two-year period from June 1969 to May 1971 .The weather radar at Hyderabad has a maximum range of 400 kill.
On the use of wind direction fieid for the estimation of wind speed field
Authors: SHAIKH Z. E. , DATTA R. K.
Published: February 2022

This paper describes an objective scheme to estimate wind speed from the available isogonal field in the interior region and wind speed and direction for the boundary region. As a first step, the mean monthly wind field is taken as a guess field for the interior region. The divergence field is then computed, which along with the wind direction for the interior region is used to improve the guess field in successive scans, so as to match it with a the wind field along the boundary.

This method has been tested over central India, a region of good conventional network. The results of the scheme which has potential advantages for augmenting data in otherwise sparse data region, is discussed.
Ozone concentration studies near the ground at Poona- Part I: Diurnal, seasonal and other time variations and ozone flux measurements
Authors: TIWARI V. S. , SREEDHARAN C. R.
Published: February 2022

Using a Brewer bubbler ozone sensor, designed and developed in the Instruments Research Laboratories of the India Met. Dep. continuous measurements of ozone concentration near the ground were made at Poona (18°N, 73°E) for one year 1969,70. There is a marked diurnal variation in surface ozone concentration which clearly follows the diurnal variation of temperature and is again a maximum during the pre-monsoon hot season months and a minimum during the monsoon. The surface ozone concentration also shows a pronounced seasonal variation, with a minimum during the monsoon months and a maximum during the pre-monsoon hot weather months. A secondary maximum in ozone concentration occurs in the forenoon during the winter months, associated with the breakdown of temperature inversion that occurs near the ground.

From continuous measurements of surface ozone made with three electrochemical sensors exposed at three levels, 0,15 and 35 m above the ground, the ozone flux was calculated using the rate of decay method used by Kroening and Ney, and Regener's profile method. The profile method gives values of 1. 71 to 7. 04X 1011 mol/cm2/sec and the rate of decay method gives 4.2 to5.6 x 10l1mol/cm2/sec which are in good agreement with the flux values reported by other investigators.
Analytical methods for calculating precipitating relativistic electron effects in the D region
Authors: CITRYNELL HAROLD
Published: February 2022

Equations for calculating the penetration and loss of energy by precipitating relativistic electrons in the D region of the atmosphere, as well as the amount of ionization caused by these electrons are derived and discussed beginning with basic physical principles related to high energy electrons.
Crustal structure of the Bay of Bengal and adjacent seas
Authors: VARMA G. S.
Published: February 2022

The time-distance curves, plotted from the first onsets of P-waves, recorded by the coastal seismograph stations for the earthquakes originating from the Bay of Bengal and Andaman and Nicobar Islands, indicate a single layered crust in this region. The depth to the Moho has been determined as 25.4 km. The velocities at the upper layer and at the top of the mantle have been determined as 6.28 ± 0. 04 and 7.97 ± 0.01 km/sec respectively. The granitic layer was found totally absent.
Crustal studies in the Himalayan region: Part-I Dalhousie- Mandi section
Authors: KAMBLE V. P. , VERMA R. K. , CHAUDHURY H. M.
Published: February 2022

The parameters of 30 shocks in the Beas Project area in the foothills of Himalayas have been determined and from them the velocities of different phases within the crust have been calculated. All the 30 events were found to be of shallow focal depth, their foci lying within the granitic layer. The mean thickness of granitic and basaltic layers in this area was calculated as 24 and 21 km respectively and the depth of Moho as 45 km. The results have been verified for different focal depths.
A study of maximum values of within-storm rainfall
Authors: AYYAR P. S. HARIHARA , TRIPATHI N.
Published: February 2022

Design engineers often require adjustment factors for converting the among-storm rainfall to within-storm rainfall. For this purpose depth-transformation curves for 2-year return period for the Indian region have been compiled and presented. For return periods of 25 years and above the adjustment factor was found to be nearly 1.0.
Interpretation of the U.S.A. Oceanographer sounding and Radon data over the Arabian Sea during June 1967
Authors: RAO Y. P. , DESAI B. N.
Published: February 2022

U.S.A Oceanographer sounding and radon data during June 1967 have been discussed with reference to the synoptic charts. During the period 14 to 21 June there was above the surface layer of maritime air, less moist air with nearly saturation adiabatic lapse from the south Arabian Sea side instead of the dry continental air from northeast Africa and Arabia. The Oceanographer soundings compare well with those at Bombay, if one keeps in mind the effect of the Ghats for the later location. The radon data show that there was presence of the maritime air from across the equator, which had got mixed to some extent with continental air from northeast Africa and Arabia; the high radon values off Saurashtra-Konkan were not due to vertical mixing of the lower maritime air with the upper continental air.
Ozone distribution over India
Authors: TIWARI V. S.
Published: February 2022

Using Dobson ozone spectrophotometer data from a network of six stations in India, the spatial and temporal distribution of total ozone over the country and its vertical distribution in the atmosphere during 1964-1969 have been studied. The study confirms earlier observations and shows that over stations north of 25°N the seasonal increase in total ozone is caused by * fractional increase in all layers from the ground to 28 km, the main contribution coming from the layers between 10 and 24 km. Above 28 km the concentration changes roughly in accordance with photochemical production. In lower latitudes south of 25°N an increase in total ozone amount during the annual cycle is caused by a gradual increase in all the layers from the ground to 36 km, above which the variation is negligible.
An electronic counter for the radiation integrator
Authors: IYER N. V.
Published: February 2022

The paper describes a four-figure electric counter meant for use with the radiation integrator. The counter consists of decade counters made up of four flip-flops in cascade with gated feed back to eliminate the additional six states, and decoders made up of transistors. The display in on numicator tubes. The counter accepts a wide range of sharp pulses of amplitude 1 to 6v upto a frequency of 5 KHz.
Result of operational cloud seeding experiment over Rihand catchment in northeast India
Authors: KAPOOR R. K. , KRISHNA K. , DE U. S. , NAIR K. G. S. , TALWAR I. C. , SHARMA S. K. , MURTY BH. V. RAMANA
Published: February 2022

A cloud seeding experiment, on operational basis, was undertaken during August-September, 1973 over the catchment area of the Rihand reservoir In the state of Uttar Pradesh, While the intended seeding operation was done on many days, the same could not be accomplished, for unavoidable reasons, on a number of days during the above period. Considering the latter category of days as control days and the areas adjoining the cases involving the catchment as control areas, the result of the experiment was evaluated. The analysis suggested rainfall increase in the catchment area, due to seeding, by over 17 per cent. The increase, however, is statistically not significant.