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Narendra Singh ¹, Raman Solanki ¹, N. Ojha ², M. Naja ¹, U. C. Dumka ¹, D. V. Phanikumar ¹, Ram Sagar ¹, S. K. Satheesh ³, K. Krishna Moorthy ⁴, V. R. Kotamarthi ⁵, S. K. Dhaka ⁶

Affiliations
1 Aryabhatta Research Institute of Observational Sciences, Nainital 263 002, IN
2 Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, DE
3 Center for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bengaluru 560 012, IN
4 ISRO Head Quarters, Bengaluru 560 231, IN
5 Environmental Science Division, Argonne National Laboratory, Illinois, US
6 Radio and Atmospheric Physics Lab., Rajdhani College, University of Delhi, Delhi 110 015, IN

Abstract

We present the measurements of cloud-base height variations over Aryabhatta Research Institute of Observational Science, Nainital (79.45°E, 29.37°N, 1958 m amsl) obtained from Vaisala Ceilometer, during the nearly year-long Ganges Valley Aerosol Experiment (GVAX). The cloud-base measurements are analysed in conjunction with collocated measurements of rainfall, to study the possible contributions from different cloud types to the observed monsoonal rainfall during June to September 2011. The summer monsoon of 2011 was a normal monsoon year with total accumulated rainfall of 1035.8 mm during June-September with a maximum during July (367.0 mm) and minimum during September (222.3 mm). The annual mean monsoon rainfall over Nainital is 1440 ± 430 mm. The total rainfall measured during other months (October 2011-March 2012) was only 9% of that observed during the summer monsoon. The first cloud-base height varied from about 31 m above ground level (AGL) to a maximum of 7.6 km AGL during the summer monsoon period of 2011. It is found that about 70% of the total rain is observed only when the first cloud-base height varies between surface and 2 km AGL, indicating that most of the rainfall at high altitude stations such as Nainital is associated with stratiform low-level clouds. However, about 25% of the total rainfall is being contributed by clouds between 2 and 6 km. The occurrences of high-altitude cumulus clouds are observed to be only 2-4%. This study is an attempt to fill a major gap of measurements over the topographically complex and observationally sparse northern Indian region providing the evaluation data for atmospheric models and therefore, have implications towards the better predictions of monsoon rainfall and the weather components over this region.

Keywords

Ceilometer, Central Himalaya, Cloud-Base, GVAX, Monsoon.

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S. K. Dhaka ¹, R. A. Kaushik ², Laxman Jat ³

Affiliations
1 National Research Centre on Seed Spices, Tabiji, Ajmer (Rajasthan), IN
2 Maharana Pratap University of Agriculture and Technology, Udaipur (Rajasthan), IN
3 Department of Horticulture, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur (Rajasthan), IN

Abstract

Numerous common eggplant varieties have been developed in India, which when grown under variable environments, the magnitude of the growth and flowering is influenced by them. In order to determine the reasons for such variations the effect of the growing conditions on growth and flowering from the eggplant cultivars with the region specific in production were investigated. The cultivars were investigated during four successive environments at two different locations in Rajasthan with contrasting environmental components such as soil and climate. The phenotypic response of the genotypes was followed with a focus on the size of the growth and the direction of flowering within the group of genotypes as a result of each factor: season, location of growing, genotype and their complex interactions. The collected data were analyzed and provided sufficient information on the genotype×environment interaction. Significant differences were found among the investigated genotypes by growth and earliness traits regardless of their specific response to the year conditions and the location. The genotype×environment interaction was significantly high and non-linear. This means that under changeable environments the different cultivars react differently and can, therefore, be grouped according to the growth and earliness stability. This is very clear from the environmental mean scores, environments E₁ was more stable with a lowest mean value for earliness traits and highest mean value had the highest genotypic response for growth traits. Seven genotypes were found to be stable across the environments for days to anthesis of first flower, eight genotypes were found stable for days to 50 per cent flowering and ten genotypes were also found stable for days to first fruit picking. Among the stable genotypes for earliness the Pusa Upkar and Punjab Sadabahar×Pusa Upkar were found to be stable for all the earliness traits. They earliness below the average mean days of all the genotypes under test, with a slope of unity and the mean square due to deviation from regression equal to zero. The five genotypes were identified for leaf area, four genotypes for plant height, three genotypes for plant spread and two genotypes for number of branches per plant as most widely adapted genotypes for growth parameters based on stability analysis. Thus, these stable genotypes can be recommended for commercial cultivation over wide range of environments or can be used in further breeding programmes.

Keywords

Eggplant, Environment, Genotype, Interaction.

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V. Kumar ¹, S. K. Dhaka ¹, V. Panwar ¹, Narendra Singh ², A. S. Rao ³, Shristy Malik ³, S. Yoden ⁴

Affiliations
1 Radio and Atmospheric Physics Lab, Rajdhani College, University of Delhi, Delhi 110 015, IN
2 Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital 263 002, IN
3 Department of Applied Physics, Delhi Technical University, Delhi 110 042, IN
4 Department of Geophysics, Kyoto University, Kyoto 606850, IN

Abstract

Influence of the solar cycle on temperature structure is examined using radio occultation measurements by COSMIC/FORMASAT-3 satellite. Observations from January 2007 to December 2015 comprising 3,764,728 occultations, which are uniformly spread over land and sea, have been used to study temperature changes mainly in the troposphere along with the solar cycle over 60°N–60°S geographic latitudes. It was a challenging task to identify the height at which the solar cycle signal could be observed in temperature perturbations as different atmospheric processes contribute towards temperature variability. Using a high spatial resolution dataset from COSMIC we are able to detect solar cycle signal in the zonal mean temperature profiles near surface at 2 km and upward. A consistent rise in the interannual variation of temperature was observed along with the solar cycle. The change in the temperature structure showed a latitudinal variation from southern to northern hemisphere over the period 2007–2015 with a significant positive influence of sunspot numbers in the solar cycle. It can be concluded that the solar cycle induces changes in temperature by as much as 1.5°C. However, solar cycle signal in the stratospheric region could not be identified as the region is dominated by large-scale dynamical motions like quasi-biennial oscillation which suppress the influence of solar signal on temperature perturbations due to its quasi-periodic nature.

Keywords

Radio Occultation, Solar Cycle, Sunspot Number, Tropospheric Temperature.

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