Multiyear Observations of Deposition-Mode Ice Nucleating Particles at Two High-Altitude Stations in India

Ice nucleating particle(INP) measurements were made at two high-altitude stations in India. Aerosols collected on filter paper at Girawali Observatory, Inter University Center for Astronomy Astrophysics(IGO), and at the Radio Astronomy Center, Ooty(RAC), were activated in deposition mode using a thermal gradient diffusion chamber to determine the INP concentrations. The measurement campaigns at IGO were conducted during 2011, 2013 and 2014, and at RAC during 2013 and 2014. When the aerosol samples were exposed to an ice supersaturation of between 5% and 23% in the temperature range~(-1)7.6?C to-22?C, the maximum INP number concentration at IGO and RAC was 1.0 L~(-1) and 1.6 L~(-1), respectively.A maximum correlation coefficient of 0.76 was observed between the INP number concentration and ice supersaturation. The airmass trajectories analyzed for the measurement campaigns showed that the Arabian Desert and arid regions were the main INP contributors. Elemental analysis of particles showed the presence of Na, Cl, Si, Al, Fe, Cu, Co, Cd, S, Mn and K, as well as some rare-Earth elements like Mo, Ru, La, Ce, V and Zr. When aerosols in the size range 0.5–20 μm were considered, the fraction that acted as INPs was 1 : 10~4 to 1 : 10~6 at IGO, and 1 : 10~3 to 1 : 10~4 at RAC. The higher ratio of INPs to aerosols at RAC than IGO may be attributable to the presence of rare-Earth elements observed in the aerosol samples at RAC, which were absent at IGO.     

Prediction and error growth in the daily forecast of precipitation from the NCEP CFSv2 over the subdivisions of Indian subcontinent

This study investigates the forecast skill and predictability of various indices of south Asian monsoon as well as the subdivisions of the Indian subcontinent during JJAS season for the time domain of 2001–2013 using NCEP CFSv2 output. It has been observed that the daily mean climatology of precipitation over the land points of India is underestimated in the model forecast as compared to observation. The monthly model bias of precipitation shows the dry bias over the land points of India and also over the Bay of Bengal, whereas the Himalayan and Arabian Sea regions show the wet bias. We have divided the Indian landmass into five subdivisions namely central India, southern India, Western Ghat, northeast and southern Bay of Bengal regions based on the spatial variation of observed mean precipitation in JJAS season. The underestimation over the land points of India during mature phase was originated from the central India, southern Bay of Bengal, southern India and Western Ghat regions. The error growth in June forecast is slower as compared to July forecast in all the regions. The predictability error also grows slowly in June forecast as compared to July forecast in most of the regions. The doubling time of predictability error was estimated to be in the range of 3–5 days for all the regions. Southern India and Western Ghats are more predictable in the July forecast as compared to June forecast, whereas IMR, northeast, central India and southern Bay of Bengal regions have the opposite nature.     

Interpolation study on ambient gamma levels in parts of Khasi Hills,Meghalaya (India): Preliminary findings for U exploration

This paper discusses an experimental approach to examine uranium exploration avenue over the geologically extended parts of Mahadek basin in Meghalaya, amid some of the environmental constraints. Study comprises periodic measurements of prevailing ambient gamma levels across 320 georeference points, in relation to the major litho units of Mahadek basin, covering 673 line km of Khasi Hills. Acquired sample data points were then analysed in geostatistical software (Surfer^TM) to develop analytical model of sample variogram having bearing on the uranium exploration in the area. Study findings have given encouraging surface indicators with mostly elevated gamma levels over the parts of West Khasi Hills. Delineated gamma anomalous zones are lithologically well correlated including to that of existing uranium occurrences in the basin. Identified anomalous zones over the parts of West Khasi Hills by this study work, are mainly associated with the Mahadek sandstone (Upper and Lower Mahadek) and Precambrian basement granites. Lower Mahadek sandstone is host rock for uranium mineralisation in the basin. Initial findings suggest with the closer spatial resolution (～1 km) of sample data points, the approach adopted by the study work holds promising application in locating potential uranium exploration targets especially to the extended and inaccessible parts of the basin.     

Phylogenetic analysis and biological characteristic tests of marine bacteria isolated from Southern Ocean (Indian sector) water

Fifty-seven bacteria were isolated from Southern Ocean(Indian sector) water samples which were collected from different latitude and longitude of the ocean. All the isolates were able to grow at 4°C, 20°C, 37°C and tolerable Na Cl concentration up to 13.5%(w/v). 29 out of 57 isolates were identified using 16 S rDNA amplification and the sequences were submitted to National Center for Biotechnology Information(NCBI). All the isolates were classified by using Ribosomal Database Project(RDP) and found that isolates belongs to Proteobacteria and Bacteriodes. The average G+C content was 56.4%. The isolates were screened for the presence of extracellular enzymes, viz. amylase, catalase, urease, esterase, lipase and protease. The disc diffusion method is used to screen antibiotic production by the isolates against four pathogenic bacteria, viz. Salmonella typhimurium(NCIM 2501),Staphylococcus aureus(NCIM 2122), Bacillus subtilis(NCIM 2193), and Pseudomonas aeruginosa(NCIM 2036).Nine out of 29 were found to be antibiotic producer.     

The future of mountain agriculture amidst continual farm-exit,livelihood diversification and outmigration in the Central Himalayan villages

Agrarian patterns in mountain ecosystems have seen a considerable change in the past decades with a vast proportion of the population abandoning traditional agriculture and diversifying their livelihood options, primarily through out-migration. This trend is especially common amongst the subsistence based family-farming communities in developing countries. This study aims at assessing methods of livelihood diversification and factors influencing farm-exit in Central Himalayan villages of Uttarakhand, India, while trying to understand local perspectives on challenges in pursuing agriculture as a viable livelihood option. We collected qualitative and quantitative data from 951 households across 60 villages evenly distributed across six hill districts of Uttarakhand, using key-person interviews and household surveys. The results of the study highlight that farm-exit is significantly influenced by livelihood diversification, number of migrants, number of female family members, and availability of irrigation facilities. In general, perception of the respondents towards agriculture as a viable livelihood option is rather unenthusiastic, with 87% of the respondents citing human wildlife conflict as the main challenge in pursuing farming, amongst several other challenges. Diversification is an integral component of present rural economy with 80.13% of the total population dependent on more than one source of income, to maintain their livelihoods. However, there is no statistically significant influence of livelihood diversification on annual income of the household. If agro-based entrepreneurial ventures are to be promoted in the region there is an urgent need for timely introduction of radical policy, institutional, and land-reforms. Economic uplifting of the local population through such efforts can also be a possible solution to the growing trends of out-migration in the state.     

RESISTIVITY TYPE CURVES OVER OUTCROPPING VERTICAL DYKE—I *

The theoretical horizontal resistivity profiles over an outcropping vertical dyke for various parameters-electrode spacing, vein-width and resistivity contrast—with inline alpha, beta and gamma-Wenner electrode systems are described. The resistivity profiles present a most bewildering variety of shapes as compared to those in resistivity soundings. The analysis of type curves suggests suitable electrode configuration for detection of wide, moderately wide, and thin veins. The negative apparent resistivity values on the gamma anomalies for resistive vein over certain vein-widths of higher positive values of resistivity reflection factor contradict the concept of apparent resistivity hitherto held.