016869   Tyagi A;Mazumdar A B;Khole M;Gaonkar S B; Sunitha Devi;Ramanathan R A N (NO, India Meteorological Dep, New Delhi, Email: ajit.tyagi@gmail.com) : Re-determination of normal dates of onset of southwest monsoon over India. Mausam 2011, 62(3), 321-8.

The onset of southwest monsoon over various parts of the country can be early, timely or late as compared to a set of normal dates. Advance of monsoon could be either rapid or slow or sometimes there could be prolonged stagnation in the advance of monsoon. The timing of the monsoon onset is of vital importance to the agricultural sector and water replenishment. The climatological normal dates of onset which are being used at present are based on a much older data set (1901-1940) obtained from 149 stations. In this study, the climatology of the summer monsoon onset over different parts of India is derived using the mean pentad precipitation data of 569 stations spread all over the country, from 1971-2000. It has been observed that the revised dates of onset of monsoon over the Andaman Sea is 20 May, over Kerala is 1 June, over the northeastern parts is 5 June and the date of monsoon covering the entire country is 15 July (same as the existing dates). Considerable differences between the existing and the re-determined dates of onset are noticed over parts of south peninsula and western parts of central and adjoining northwest India where the re-determined dates are advanced by 1 to 3 days and delayed by 10 to 15 days respectively with respect to the existing normal dates of arrival of monsoon. The Standard Deviation of the re-determined normal dates ranges between 7 to 14 days with larger values over the northwest and west central parts and interior peninsular India.

5 illus, 1 table, 11 ref

016868   Thamban M;Naik S S;Laluraj C M;Ravindra R (National Centre for Antarctic and Ocean Research, Headland Sada, Goa-403 004, Email: meloth@ncaor.org) : High resolution climater reconstructions of recent warming using instrumental and ice core records from Coastal Antarctica. Mausam 2011, 62(4), 665-72.

In-situ observational record of Antarctic surface temperatures is rather sparse. Proxy based ice core studies are thus critical for reconstructing the past climate change on centennial and decadal time scales. The present study review the available instrumental and proxy records from the Dronning Maud Land region of East Antarctica as well as report recent evidences of Antarctic climate change and its global linkages. The monthly mean air temperature records of the Novolazarevskaya (Novo) station, which is the longest (since 1961) and continuous meteorological record in this region, revealed a significant warming trend at a rate of 0.25 °C / decade. To understand the spatial and temporal consistency of this warming, well-dated ice cores from the coastal Dronning Maud Land region were assessed. All proxy records consistently suggest an enhanced warming up to +0.12 °C / decade. This is further supported by a recent assessment of stable oxygen and hydrogen isotope proxy records from two high resolution ice cores (IND-25/B5 and IND-22/B4) from this region. Among these records, the IND-25/B5 provided ultra-high-resolution data for the past 100 years (1905-2005) and the IND-22/B4 core represented the past <126>470 years (1530-2002) of Antarctic change. These ice records provided insights on the influence of solar forcing on Antarctic climate system as well as its linkages with the tropical and mid-latitude climatic modes like the Southern Annular Mode (SAM) and El Nino Southern Oscillation (ENSO). The calculated surface air temperatures using these records showed a warming by 0.06-0.1 °C / decade, with greatly enhanced warming during the past several decades (<126>0.4 °C / decade). It is confirmed that the coastal areas of Dronning Maud Land are indeed warming and the trend is apparently enhancing in the recent decades.

4 illus, 30 ref

016867   Talukdar M;Singh S (Geography Dep, North-Eastern Hill Univ, Shillong-793 022) : Land use changes in Tinsukia district, Assam. Ann Natn Ass Geogr 2011, 31(1), 81-92.

Present paper examines the changes in general land use of Tinsukia district located in the upper most part of the Brahmaputra Valley. Collecting statistics of land use and other related attributes from different offices of Government of Assam, Guwahati for the last 13 years (from 1992-93 to 2004-05), the recent changes in the land use were studied. It is found that there is a significant change in land use pattern and conversion of land from the categories of forest, barren and waste land to the agriculture land. There is decrease in the forest land at an average annual rate of 0.435 percent which is fairly higher than that of the state average (0.03 percent). On the other hand, there is a noticeable increase in the Net Sown Area at an average annual rate of 0.122 percent which is also far higher than the state average. Such fast changes in land use of the district show that expansion and intensification processes of agricultural land use have been accelerated by intensifying the technological inputs. The effects of market forces and expansion of road network in the district also facilitates intisification of agriculture practices.

4 illus, 4 tables, 17 ref

016866   Srivastava A;Das I M L;Oza S R;Mitra A;Dash M K;Vyas N K (K. Banerjee Centre of Atmospheric & Ocean Studies, Allahabad Univ, Allahabad-211 002) : Assessment of sea ice melting rates in the Antarctic from SSM/I observations. Mausam 2011, 62(4), 601-8.

Sea ice governs the fluxes of heat, moisture and momentum across the ocean-atmosphere interface. Because it is thin, sea ice is vulnerable to small perturbations within the ocean and the atmosphere, which considerably change the extent and thickness of the polar ice cover. Thus, sea ice is a climate change indicator. The DMSP SSM/I monthly ice concentration data over the Antarctic region have used to calculate the monthly sea ice extents (August to February) for each year during 1988-2006. Melting rates based on seasonal cycle of solar irradiance as well as the SSM/I data have been calculated. Compared to the melting rates based on seasonal cycle of solar irradiance, the SSM/I estimated melting rate, is less in the beginning of September and increases to its peak value by the end of December. The observed melting rate behaviour indicates that apart from the seasonal cycle of solar irradiance, it is controlled by other mechanisms also. The present study estimates the feedback impact factor, response time, accelerating and decelerating melting rate duration for the period 1988-2006.

8 illus, 1 table, 9 ref

016865   Sonbawne S M;Devara P C S;Reddy R C;Safai P D;Salvekar P S (Indian Institute of Tropical Meteorology, Dr. Homi Bhabha Road, Pune-411 008, Email: devara7@gmail.com) : Polar aerosol characterization, sources and impacts. Mausam 2011, 62(4), 585-94.

Aerosols are known to cause important effects on weather and climate of Polar Regions! and their radiation balance of the polar surface-atmosphere system, especially in the regions characterized by high surface-reflectance conditions, which also prevails the heterogeneous chemistry of aerosols. Therefore, the knowledge of the aerosol physical and optical properties needs to be improved on both spatial and temporal scales. To characterize these physico-chemical and optical properties, studies have been carried out over both the polar regions [Antarctica ('Maitri' (70.76°S, 11.74°E) and Arctic "Himadri" (79°N, 11°E) during the summer period of 24th (2004-05), 26th (2006-07) Indian Antarctica Expedition, and during 14th Indian Arctic Expedition in 2010. Total column aerosol optical depth (AOD), ozone (TCO), precipitable water content (PWC), and direct radiative forcing using a multi-channel solar-radiometer (Microtops II); and short-wave global radiative flux using a wide-band pyranometer for their characteristics. In the Arctic, an Andersen Sampler, Black Carbon Aethalometer was also operated to determine the chemical properties of aerosols. The aerosol optical, physical and radiative properties, and their interface with simultaneously measured gases and their chemical composition have been investigated. The results showed that the daily mean AOD at a characteristic wavelength of 500 nm was found to be 0.042 with an average Angstrom coefficient of 0.24, revealing abundance of coarse-mode particles in Antarctica, and Arctic average AOD was observed 0.11 with an average Angstrom coefficient of 2.84, suggesting fine-mode particles. The TCO measured by the surface-based ozone monitor matched reasonably within 5% with that of the Total Ozone Mapping Spectrometer (TOMS) satellite sensor. Variability in ozone on daily scale, during the study period, was less than 4% over the Antarctica region and more or less same for Arctic. The January 2005 fluxes were found to be less by about 20% as compared to those in February 2005. The average short-wave direct radiative forcing due to aerosols showed cooling at the surface with an average value of -0.47 W/m² during the study period. In this paper, we briefly describe the equipment deployed, data archival, their analysis techniqes and salient results obtained over the Indian polar stations, 'Maitri' and 'Himadri'.

8 illus, 18 ref

016864   Singh R B;Gurjar A K (Geography Dep, Delhi School of Economics, Delhi Univ, Delhi-110 007) : Climate change vulnerability of agriculture in arid region of Rajasthan, India. Ann Natn Ass Geogr 2011, 31(1), 21-38.

Climate change is emerging as threat to the world population, bigger than any war or natural calamity. Arid regions are also influenced by the vulnerability to climate change which differs with income and technology. The accessibility to natural resources determines the capability to cope with climate change. Mitigation measures are important to be implemented along with measures to enhance the adaptive capacity. But prior to this, vulnerability assessment for climate change should be done in order to know vulnerable sectors and people, so that priorities can be defined. In India about 61 per cent of total area falls in arid category. Arid regions are characterized by scarcity of water resources, which makes them more vulnerable to climate change. The vulnerability of arid regions of India is also increased by its demography, as it has highest density of population compared to other arid regions on the same latitude. The average temperature of the region has increased by 0.45° C in last 30 years along with a high variability in rainfall. Traditional water harvesting and tillage techniques are best-suited solutions to fight against climate change.

9 illus, 1 table, 24 ref

016863   Singh O P;Singh U P;Lal R P (NO, India Meteorological Dep, New Delhi-110 003, Email: singh.op@imd.gov.in) : Recent trends and variations in surface meteorological parameters over Indian Antarctic station maitri. Mausam 2011, 62(4), 547-56.

Utilizing surface meteorological data of temperature, pressure and wind of recent two decades, 1991-2010 over Indian Antarctic research station Maitri the trends and variabilities in surface meteorological parameters have been discussed. The trend in mean air temperature at Maitri has been -0.4/decade during past two decades showing no impact of global warming on Maitri surface temperature. There is no trend in surface pressure at Maitri during last two decades. Mean surface wind speed has shown slight increasing trend during the decade 1991-2000 whereas it has shown slight decreasing trend during the decade 2001-2010. However, there are large interannual variations in surface parameters and the linear trends seem to be the result of such variations. During Jan-March of two contrasting monsoon years 2009 and 2010 interesting anomalies in surface pressure at Maitri have been observed. Surface pressure was anomalously lower at Matri in Jan-March of drought year 2009 whereas positive pressure anomalies prevailed during the same period of excess monsoon year 2010. Negative temperature anomalies during January-March over Maitri preceded drought monsoon 2009 and positive anomalies prevailed during the same period before good monsoon 2010.

7 illus, 21 ref

016862   Singh O P;Singh H (NO, India Meteoroligical Dep, New Delhi, Email: singh.op@imd.gov.in) : Variability of scatterometer based surface vorticity over arabian sea and its use in monsoon onset forecasting. Mausam 2011, 62(3), 361-74.

Presents the results of the study undertaken to investigate the changes in the surface wind and vorticity fields over south Arabian Sea and adjoining north Indian Ocean and their association with monsoon onset over Kerala. For this purpose QuikSCAT daily gridded data of recent 10 years (2000-2009) have been utilized. The results show that there is a rising trend in the surface wind speed and vorticity over south Arabian Sea about 4-7 days before the monsoon onset over Kerala. Thus, the rising trends in the surface wind speed and vorticity over south Arabian Sea seem to be a good precursor of monsoon onset over Kerala. Continuous monitoring of Oceansat-2 scatterometer surface wind and vorticity fields over south Arabian Sea and adjoining north Indian Ocean during 15th May to 15th June could provide predictive indications of monsoon onset over Kerala on medium range scale.

7 illus, 13 ref

016861   Singh H;Datta R K;Suresh Chand;Mishra D P; Kannan B A M (NO, India Meteoroligcal Dep, New Delhi, Email: hsng55@yahoo.com) : Hailstorm of 19th April 2010 over Delhi using doppler weather radar observations. Mausam 2011, 62(3), 433-40.

Hailstorm of 19th April 2010 over Delhi has been studied using observations from Doppler Weather Radar (DWR) installed at Palam. The data was analysed at Central Server located at India Meteorological Department HQ using IRIS software (of M/s SIGMET-VAISALA, Finland) installed in the server. Reflectivity of 45 dBZ level was found to be 6.3 km above freezing level at the time of hailstorm which corresponds to 100% (obtained from probability function diagram of Witt et al. (1998)) probability of hail. Reflectivity was more than 55 dBZ upto 10 km and 7 km at 1110 UTC and 1120 UTC respectively which exceeds the hail threshold limit adopted in NEXRAD (USA). Maximum of 62 dBZ was observed at about 3 km at 1110 UTC and 64 dBZ at 3.5 km at 1120 UTC in Radar Data. Very high values of Vertical Integrated Liquid (VIL) ranging from 58.7 kg/m² to 64.1 kg/m² were observed between 1040 UTC and 1120 UTC which is higher than 43 kg/m², the threshold value for occurrence of hail. Severe Hail Index (SHI), Probability of Severe Hail (POSH) and Maximum Expected Hail Size (MEHS) were computed to verify the applicability of enhanced Hail Detection Algorithm (HDA) outlined by Witt et al. (1998) to Indian conditions. The Maximum Expected Hail Size (MEHS) computed using Doppler Weather Radar observations were 2.5 cm, 2.6 cm and 2.0 cm respectively at 1050 UTC, 1100 UTC and 1110 UTC which are in close agreement with the reported hail size. The study confirms that HDA and other thresholds of reflectivity and VIL used for hail detection and warnings in NEXRAD (USA) can be used in Indian conditions also.

2 illus, 2 tables, 22 ref

016860   Singh D S;Ravindra R (Centre of Advanced Study in Geology, Lucknow Univ, Lucknow-22600, Email: dhruvsensingh@rediffmail.com) : Control of glacial and fluvial environments in the Ny-alesund region, Arctic. Mausam 2011, 62(4), 641-6.

Ny-Alesund, located in Svalbard, Arctic exhibits complex topography and geomorphic features evolved by various sedimentary environments under direct control of climate and tectonics. The controls of glacial and fluvial environments were analyzed on the basis of field documentation of geomorphic features evolved by small valley glaciers (Vestre brogger and Midre loven) and streams originating from it. These terrestrial valley glaciers are characterized by convex wrinkled surface, crevasses, bergchrunds, supraglacial streams, longitudinal debris strips, lateral moraines, recessional moraines, hummocky moraines, thrust moraines, convex longitudinal profile with breaks in slope, fractures and joints. The glacial deposits are made up of very poorly sorted clast to matrix supported boulders with varying sizes of clast, matrix and gravels. The matrix supported facies underlain by clast supported facies indicate the increasing energy of the glacier and so the cold climate. The bi-modal palaeocurrent pattern of moraines suggests two prominent directions for the movement of glaciers in the past under direct control of tectonic activity. The granulometric analysis of the streams indicate moderately sorted medium to coarse sand. The mean grain size decreases from origin to the middle reaches of the river and increases towards its mouth. The percentage of the finer sediments decreases and coarser fragments increases in the downstream direction. The results of the granulometric parameters which are contrary to the normal fluvial system are due to the control of tectonic activity. The present study provides the basic characteristics and activity of the glacial and fluvial environments the interpretation of, which explains the control of tectonic activity in this region.

7 illus, 2 tables, 9 ref

016859   Singh B (Meteorological Office, Civil Aviation Training College, Bamrauli, Allahabad, Email: bikram.jagat@gmail.com) : Semi-quantitative precipitation forecast model for Subarnarekha catchment by synoptic analogue technique. Mausam 2011, 62(3), 457-62.

1 illus, 1 table, 2 ref

016858   Singh A D;Verma K (Centre of Advanced Study in Geology, Banaras Hindu Univ, Varanasi-221 005, Email: arundeosingh@yahoo.com) : Impact of climate induced hypoxia on calcifying biota in the Arabian sea:an evaluation from the micropaleontological records of the Indian margin. Mausam 2011, 62(4), 647-52.

High biological productivity combined with the poor ventilation produces severe oxygen depletion (hypoxia) in upper intermediate waters of the Arabian Sea. The naturally developed Arabian Sea oxygen minimum zone (OMZ) is one of the most pronounced low oxygen ocean environments known today. The OMZ impinges the Indian margin where oxygen concentration reaches values less than 0.05 ml/1 leading denitrification. In recent studies, it has been observed that the OMZ strength has varied considerably in the past, in tune with the global climate change. But the effect of changes in natural mid-water hypoxic environment on the marine biota particularly of the eastern Arabian Sea is unknown. Here, we analyzed 30,000 yr record of temporal changes in two major groups of marine calcifying microfauna pteropods secreting aragonitic shells and foraminifera secreting calcitic shells in terms of abundance and diversity variations. This study will provide an insight into our understanding of potential impact of rising atmospheric CO₂ on marine ecosystem.

2 illus, 8 ref

016857   Sikka D R;BishoyiRatna S (NO, , 40, Mausam, Vihar, Delhi-110 051, Email: drsikka@yahoo.com) : On improving the ability of a high resolution atmospheric general circulation model for dynamical seasonal prediction of the extreme seasons of the Indian summer monsoon. Mausam 2011, 62(3), 339-60.

The paper is devoted to examine the ability of a high-resolution National Center for Environmental Prediction (NCEP) TT70/L42 Atmospheric General Circulation Model (AGCM), for exploring its utility for long-range dynamical prediction of seasonal Indian summer monsoon rainfall (ISMR) based on 5-members ensemble for the hindcast mode 20-year (1985-2004) period with observed global sea surface temperatures (SSTs) as boundary condition and 6-year (2005-2010) period in the forecast-mode with NCEP Coupled Forecast System (CFS) SSTs as boundary condition. ISMR simulations are examined on five day (pentad) rainfall average basis. It is shown that the model simulated ISMR, based on 5-members ensemble average basis had limited skill in simulating extreme ISMR seasons (drought/excess ISMR). However, if the ensemble averaging is restricted to similar ensemble members either in the overall run of pentad-wise below (B) and above (A) normal rainfall events, as determined by the departure for the threshold value given by coefficient of variability (CV) for the respective pentads based on IMD observed climatology, or during the season as a whole on the basis of percentage anomaly of ISMR from the seasonal climatology, the foreshadowing of drought/excess monsoon seasons improved considerably. Our strategy of improving dynamical seasonal prediction of ISMR was based on the premise that the intra-seasonal variability (ISV) and intra-annual variability (IAV) are intimately connected and characterized by large scale perturbations westward moving (10-20 day) and northward moving (30-60 day) modes of monsoon ISV during the summer monsoon season. As such the cumulative excess of B events in the simulated season would correspond to drought season and vice-versa. The paper also examines El Nino-Monsoon connections of the simulated ISMR series and they appear to have improved considerably in the proposed methodology. This strategy was particularly found to improve for foreshadowing of droughts. Based on results of the study a strategy is proposed for using the matched signal for simulated ISMR based on excess B over A events and vice-versa for drought or excess ISMR category. The probability distribution for the forecast seasonal ISMR on category-basis is also proposed to be based on the relative ratio of similar ensemble members and total ensembles on percentage basis. The paper also discusses that extreme monsoon season are produced by the El Nino-Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) modes in a combined manner and hence stresses to improve prediction of IOD mode in ocean-atmosphere coupled model just as it has happened for the prediction ENSO mode six to nine months in advance.

6 illus, 6 tables, 59 ref

016856   Shukla S K;Sudhakar M (Marine Sciences Dep, Goa Univ, Taleigao Plateau, Goa-403 206) : Comparison of modern and fossil diatom assemblages and their implication on sea-ice conditions in coastal Antarctic region. Mausam 2011, 62(4), 659-64.

Antarctic Coastal regions are thought to be characterized by high productivity usually dominated by diatoms. Considering their prime importance in global carbon biological pump, diatom distribution and abundance studies are sparse especially in coastal regions of Antarctica. Biogenic silica is considered to be severely affected by dissolution in the undersaturated ocean water, therefore, combined study of diatom assemblages from water column and those found in the sediments is important. Therefore, we conducted a combined study of sediment diatoms along with surface water diatoms collected from Coastal Antarctica. When the modern assemblages are compared to the fossil record, it is clear the most of the important diatoms from the summer assemblages are not preserved in the underlying sediments. The studies reveal that only F. kerguelensis is common abundant species in both water and sediment which suggests that coastal Antarctic region could be having more open ocean influence. In contrast, the presence of sea ice related diatom species from surface sediment indicate for expansion of sea ice or ice edge adjacent to the water column, however such species were not found in the overlying water samples which could be due to less sea-ice extent.

2 illus, 1 table, 42 ref

016855   Shivasharanappa;Yalakpalli A (Civil Engineering Dep, P.D.A. College of Engineering, Gulbarga, Karnataka, Email: shiva_patil11@rediffmail.com) : Physico-chemical and biological characteristics of Bhima river in Gulbarga district, Karnataka state, India. Int J chem envir pharm Res 2012, 3(1), 96-108.

Present work is aimed at assessing the water quality of the surface water of Bhima River near Hipperga village of Taluka Gulbarga, District Gulbarga, Karnataka State, India. Surface water samples collected at three sampling points, S₁ upstream of village Hipparga, S₂ near village Hipparga and S₃ downstream of village Hipparga. The samples are subjected for comprehensive physical, chemical and biological analysis using standard procedural methods and analysed for temperature, pH, total dissolved solids, total hardness, calcium hardness, magnesium hardness, chloride, sulphate, nitrate, fluoride, dissolved oxygen, biochemical oxygen demand, alkalinity, sodium, potassium and biological examination. The study revealed that the Bhima river water in the area is well within the permissible limit except total hardness, calcium hardness, magnesium hardness BOD and bacterial count (MPN-Index). All the parameters are correlated with one another and the statistical analysis of the data is presented. The analysis reveals that the surface water of the area needs some degree of treatment before consumption and it also needs to be protected from the perils of contamination.

17 illus, 4 tables, 10 ref

016854   Sharma N;Dash M K;Vyas N K;Bhandari S M; Pandey P C;Khare N (NO, National Mineral Development Corporation, Hyderabad-500 028, Email: nilaysharma76@yahoo.co.in) : Signature of ice melt over the greenland derived from MSMR (OCEANSAT-1) data. Mausam 2011, 62(4), 627-32.

In order to monitor the impact of global warming phenomena over the Polar Regions, it is necessary to monitor snow/ice melt on the Greenland and the Antarctic ice sheets. Using MSMR data, it is possible to differentiate sea ice at different concentration levels. On the basis of microwave emissivities of continental ice and sea ice, useful information on the formation and melting of the ice can be derived. Discusses different strategies to derive a melt signal from the MSMR observations for the continental ice sheets in Greenland. The Polarization Difference (PD) for 21 GHz, available from MSMR data, is studied and an appropriate threshold is selected to detect the presence of melt signal. The results of the present study have bearing on climate changes.

3 illus, 11 ref

016853   Sharma A K (NO, India Meteorological Dep, New Delhi-110 003, Email: aksimd@gmail.com) : Applications of satellite imageries for prediction of severe weather events along Maitri, Antarctica. Mausam 2011, 62(4), 617-26.

An attempt to educate the weather forecaster at Indian Scientific research Station, Maitri, Antarctica in forecasting severe weather (blizzards) using satellite images of various satellites operating in the world. The Polar stationary satellite "Trianna' has been discussed. The availability of the various types of images has also been spelt. The characteristics of satellite images has been described along with overlaying of Automatic Weather station (AWS) data explaining the occurrence of Katabatic winds which also causes blizzards. Blizzard conditions often develop on the northwest side of an intense storm system the difference between the lower pressure in the storm and the higher pressure to the west creates a tight pressure gradient, which in turn results in very strong winds or blizzards. The paper also discusses about the development that took place in Antarctic satellite meteorology since beginning.

7 illus, 4 ref

016852   Samui R P;John G;Ransure S P;Pachankar M A (NO, India Meteoroligal Dep, Pune, Email: rsamui@yahoo.com) : Factors affecting the trends in evaporation during different crop growing seasons over India. Mausam 2011, 62(3), 391-402.

Evaporation, rainfall and meteorological data for the period 1971-2004 for 58 well distributed stations over India were selected for the study. Trends of evaporation and rainfall in five regions, viz., Northwest, North, Northeast, Central and Peninsular regions of India during different crop growing seasons, viz., kharif, rabi and summer and the meteorological factors contributing towards the trend were analyzed. Annual evaporation shows decreasing trend in all the regions of the country. Trends in seasonal evaporation during kharif, rabi and summer seasons also showed decreasing trends in Northwest, North, Central and Peninsular regions of the country while few locations in Northeast India, viz., Guwahati, Dibrugarh and Tocklai showed significant increasing trend in evaporation during kharif and rabi seasons. No significant trend in annual and seasonal rainfall was observed in Indian region except a few stations in peninsular India where increasing trend was observed. Normalized anomalies of maximum temperature, relative humidity and Vapour pressure showed increasing trend in Northwest and Northern regions during all the three crop growing seasons while decreasing trend or no trend in wind velocity was observed in all the regions except in central region where increasing trend was observed during summer season. As evaporation relates to the meteorological elements, viz., temperature, sunshine duration, wind velocity and relative humidity, the likely causative meteorological factors for such changes are studied. Increasing trends in maximum temperature was observed in central and peninsular inland regions of the country during rabi and summer seasons while slight decreasing trends were observed in the Northeast region during kharif season. High positive correlation found between maximum temperature and wind velocity indicates that the trend in evaporation is mostly influenced by these two factors, increase in humidity and decrease in bright sunshine hours were both important and found correlated with the decrease in evaporation.

4 illus, 3 tables, 11 ref

016851   Salve P R;Gobre T;Krupadam R J;Shastry S; Bansiwal A;Wate S R (NO, National Environmental Engineering Research Institute (NEERI), Nagpur, Email: pr_salve@neeri.res.in) : Chemical characterization of rainwater at Akkalkuwa, India. Mausam 2011, 62(3), 425-32.

The chemical composition of rainwater changes from place to place and region to region under the influence of several major factors, viz., topography, its distance from sea and overall rainfall pattern. The present study investigated the chemical composition of precipitation at Akkalkuwa, district Nandurbar, in the State Maharashtra during southwest monsoon. The rainwater samples were collected on event basis during June-September 2008 and were analyzed for pH, major anions (F, Cl, NO₃, SO₄) and cations (Ca, Mg, Na, K, NH₄). The pH varied from 6.0 and 6.8 with an average of 6.29 ± 0.23 indicating alkaline nature and dominance of Ca in precipitation. The relative magnitude of major ions in precipitation follows the pattern as Ca<62>Cl<62>Na<62>SO₄< 62>NO₃<62>HCO3<62>NH₄< 62>Mg<62>K<62>F>H. The Neutralization factor (NF) was found to be NF_ca =0.95, NF_NH4 = 0.31, NF_mg = 0.27 and NF_k = 0.08 indicating below cloud process in which crustal components are responsible for neutralization of anions. Significant correlation of NH₄ with SO₄ and NO₃ was observed with correlation coefficient of r = 0.79 and 0.75, respectively.

1 illus, 6 tables, 21 ref

016850   Roy Bhowmik S K;Anupam Kumar;Das A K (NO, India Meteorological Dep, New Delhi-110 003) : Real-time mesoscale modeling for short range prediction of weather over maitri region in Antarctica. Mausam 2011, 62(4), 535-46.

The main objective of this paper is to implement Polar WRF model for the Maitri (Lat. 70° 45' S, Long. 11° 44' E) region at the horizontal resolution of 15 km using initial and boundary conditions of the Global Forecast System T-382 operational at the India Meteorological Department (IMD). The study evaluates the performance of the model using the conventional approach of case studies. The results of the case studies illustrated in this paper reveal that the model is capable of capturing synoptic and meso-scale weather systems. Forecast fields are consistent with the corresponding analysis fields. Synoptic charts of mean sea level pressure prepared by the Weather Service of South Africa at Pretoria are used for the model validation. The model derived meteograms of mean sea level pressure are compared against the corresponding observations. The study demonstrates the usefulness of the forecast products for short range forecasting of weather over the Maitri region. The forecast outputs are made available in the real-time mode in the national web site of IMD www.imd.gov.in. The study is expected to benefit weather forecasters at Maitri.

16 illus, 7 ref

016849   Ramesh S (NO, Anna Univ, Chennai, Tamil Nadu) : Land use in suburbia perungalathur village of Chennai metropolitan area. Ann Natn Ass Geogr 2011, 31(1), 93-9.

The term 'suburbia' gets significance because of its differing nature of development, community setup, societal organisation and human behaviour when compared to adjoining areas. Land use at the fringes of metropolitan cities, especially in developing countries, are forced to undergo a process of transformation, seamlessly, due to various politico-socio, economic and technological developments taking place. The paper aims at land use analysis of Perungalathur village of Chennai Metropolitan area.

11 ref

016848   Rajesh Prakash;Singh R K;Shukla A K;Singh D; Rana B S;Jaryal J S (NO, Indian Meteorological Department, New Delhi) : Intensity and isoseismal map of 25th November 2007 Delhi earthquake. Mausam 2011, 62(3), 417-24.

An earthquake of magnitude M_L: 4.3 occurred on 25th November 2007 (2312 UTC) in Delhi with hypocenter at 28.56°N / 77.08° E and focal depth 33.1 km. The epicenter was at about 21 km SW of Delhi University. It was widely felt in and around Delhi and created panic among the local populace. A macroseismic survey was conducted in about ten days starting from 27th November, 2007 at 89 locations covering an area of about 1500 sq. km in Delhi and its neighborhood through a questionnaire. The results of the macroseismic survey allowed establishment of spatial distribution of the earthquake effects in the form of isoseismal map generated using geo-statistical analysis tool of ArcGIS 9.1. The isoseismal map shows that most parts of Delhi region experienced an intensity of V on MMI scale, except on northern most region of Delhi where intensity was found IV. The mean isoseismal radii for the zones V, IV, III and II are 29.13, 57.78, 83.63 and 100.75 km, respectively. The orientation of elongated epicentral track of intensity field shows that the stress release was pronounced along Delhi-Sargodha ridge and earthquake was attributed to activities of this ridge.

3 illus, 1 table, 4 ref

016847   Rai R K (Geography Dep, North-Eastern Hill Univ, Shillong) : The Indian disaster scenario and its mitigation. Ann Natn Ass Geogr 2011, 31(1), 1-11.

1 table, 34 ref

016846   Radha T (Home Science Extension Education, Avinashilingam Deemed women Univ, Coimbatore-641 043) : Human impact of tsunami 2004 on the families in Nagapattinam district. Res Highlight 2011, 21(2), 88-94.

2 illus, 7 tables, 3 ref

016845   Prabhu A;Mahajan P N;Khaladkar R M (NO, Indian Institute of Tropical Meteorology, Pune, Email: amitaprabhu@tropmet.res.in) : Trends in the polar sea ice coverage under climate change scenario. Mausam 2011, 62(4), 609-16.

The development in the satellite microwave technology during the past three decades has offered an opportunity to the scientific community to access the sea ice data over the polar regions, which was otherwise inaccessible for continuous monitoring by any other means. The present study focuses on the trends in the Sea Ice Extent (SIE) over different sectors of the Arctic and the Antarctic regions and the interannual variability in their extremes. In general, the data over the period (1979-2007) reveal marked interannual variability in the sea ice cover with an increasing and the decreasing trend over the Antarctic and the Arctic region respectively. Over the southern hemisphere, only the Bellingshausen and Amundsen Seas sector shows an exceptional decreasing trend. However, in the northern hemisphere, all the sectors show a decreasing trend, with the Kara and Barents Seas sector being the most prominent one. Although, the decreasing trend of the SIE over the Arctic could be attributed to the global warming, an intriguing question still remains as to why the other polar region shows a different behaviour.

4 illus, 3 tables, 27 ref

016844   Peshin S K (India Meteorological Dep, Lodhi Road, New Delhi-110 003) : Study of SO₂ and NO₂ behaviour during the ozone-hole event at antarctica by brewer spectrometer. Mausam 2011, 62(4), 595-600.

Vertical column density of sulpjrurdioxide has been measured at Maitri (70.7°S, 11.7°E), the Indian station in the Antarctica from September, 1999 to December, 2006 by a Brewer Spectrophotometer. Simultaneously, nitrogen dioxide, ozone and the maximum value of UV-B have also been measured, we found an increase in SO₂ during Spring. An increase in NO₂ column was also found during this period but not identical with that of SO₂. These variations in SO₂ and NO₂ are not in phase with the increase in UV-B flux at the ground due to the decrease of ozone column in the stratosphere. The variation of SO₂ column is explained by the downward shift of penetration depth of UV-B radiation during the ozone-hole event.

2 illus, 18 ref

016843   Pattanaik D R;Anupam Kumar;Rama Rao Y V; Mukhopadhyay B (India Meteorological Dep, , New, Delhi-110 003, Email: pattanaik_dr@yahoo.co.in) : Simulation of monsoon depression over India using high resolution WRF model-sensitivity to convective parameterization schemes. Mausam 2011, 62(3), 305-20.

The monsoon depression of September 2008, which crossed Orissa, coast near Chandbali on 16th had contributed heavy rainfall over Orissa, Chhattisgarh and northern India along the tracki of the system. The sensitivity of three cumulus parameterization schemes viz., Kam-Fritch (KF) scheme, Grell-Devenyi (GD) scheme and Betts-Miller-Janjic (BMJ) Scheme are tested using high resolution advanced version (3.0) Weather Research Forecasting (WRF) model in forecasting the monsoon depression. The results of the present study shows that the genesis of the system was almost well captured in the model as indicated in 48hr forecast with all three convective parameterization schemes. It is seen that the track of monsoon depression is quite sensitive to the cumulus parameterization schemes used in the model and is found that the track forecast using three different cumulus schemes are improved when the model was started from the initial condition of a depression stage compared to that when it started from the initial condition of low pressure area. It is also seen that when the system was over land all the schemes performed reasonably well with KF and GD schemes closely followed the observed track compared to that of BMJ track. The performance of KF and GD schemes are almost similar till 72 hrs with lowest landfall error in KF scheme compared to other two schemes, whereas the BMJ scheme gives lowest mean forecast error upto 48 hr and largest mean forecast error at 72 hr. The overall rainfall forecast associated with the monsoon depression is also well captured in WRF model with KF scheme compared to that of GD scheme and BMJ scheme with observed heavy rainfall over Orissa, Chhattisgarh and western Himalayas is well captured in the model with KF scheme compared to that with GD scheme and BMJ scheme.

11 illus, 1 table, 18 ref

016842   Oza S R;Singh R K K;Srivastava A;Dash M K;Das I M L;Vyas N K (Space Applications Centre, Indian Space Research Organisation, Ahmedabad-380 015, Email: sandipoza@sac.isro.gov.in) : Inter-annual variations observed in spring and summer Antarctic sea ice extent in recent decade. Mausam 2011, 62(4), 633-40.

The growth and decay of sea ice are complex processes and have important feedback onto the oceanic and atmospheric circulation. In the Antarctic, sea ice variability significantly affects the primary productivity in the Southern Ocean and thereby negatively influences the performance and survival of species in polar ecosystem. In present days, the awareness on the sea ice variability in the Antarctic is not as matured as it is for the Arctic region. The present paper focuses on the inter-annual trends (1999-2009) observed in the monthly fractional sea ice cover in the Antarctic at 1 x 1 degree level, for the November and February months, derived from QuikSCAT scatterometer data. OSCAT scatterometer data from India's Oceansat-2 satellite were used to asses the sea ice extent (SIE) observed in the month of November 2009 and February 2010 and its deviation from climatic maximum (1979-2002) sea ice extent (CMSIE). Large differences were observed between SIE and CMSIE, however, trend results show that it is due to the high inter-annual variability in sea ice cover. Spatial distribution of trends show the existence of positive and negative trends in the parts of Western Pacific Ocean, Ross Sea, Amundsen and Bellingshausen Seas (ABS), Weddell Sea and Indian ocean sector of southern ocean. Sea ice trends are compared with long-term SST trends (1982-2009) observed in the austral summer month of February. Large-scale cooling trend observed around Ross Sea and wanning trend in ABS sector are the distinct outcome of the study.

5 illus, 16 ref

016841   Nagaraju D;Papanna C;Mahadevaswamy C; Lakshmikanth Raju H T;Nagesh P C;Rao K (Studies in Geology Dep, Mysore Univ, Manasagangotri, Mysore-570 006) : Hydrogeochemical evaluation of kuderu microwatershed of Kabini river basin, Karnataka, India. Nat Envir Pollut Technol 2011, 10(1), 95-8.

Microwatershed covering Kuderu, Dasanur and other adjoining villages was selected for a detailed accounting of the groundwater budget. Groundwater is the main source of water for agriculture and livestock. The net annual recharge available for minor irrigation is estimated at 438 ham thereby reaching grey category. Further exploration without recharging the groundwater body needs vigilance. Construction of artificial recharge structures are suggested. The quality of water is generally suited for drinking and irrigation purposes.

1 illus, 1 table, 5 ref

016840   Mohapatra M;Adhikary S (NO, India Meteorological Dep, New Delhi-110 003, Email: mohapatra_imd@yahoo.com) : Modulation of cyclonic disturbances over the North Indian ocean by Madden - Julian oscillation. Mausam 2011, 62(3), 375-90.

The relationship of genesis and intensity of cyclonic disturbances (CDs) over the north Indian Ocean with the Madden - Julian Oscillation (MJO) has been examined using 33 years (1975 - 2007) data of MJO index and best track of (CDs) developed by India Meteorological Department (IMD). The MJO index based on outgoing long wave radiation (OLR) and zonal wind in upper (200 hPa) and lower (850 hPa) troposphere (Wheeler and Hendon, 2004) has been used for this purpose. The MJO strongly modulates the genesis and intensity of CDs over the north Indian Ocean. However there are other factors contributing to cyclogenesis over the north Indian Ocean, as about 60% of cyclogenesis during monsoon and post-monsoon seasons are not significantly related with MJO. While the probability of cyclogenesis during monsoon season is higher with MJO in phase 4 and 5 (Maritime Continent), that during post-monsoon season is higher with MJO in phase 3 and 4 (east Indian Ocean and adjoining Maritime Continent). It indicates that while possibility of genesis during monsoon season is significantly suppressed with active MJO at phase 1, 7 and 8 (Africa, western Hemisphere and adjoining Pacific Ocean), there is no significant relationship between genesis and active MJO at phase 1, 7 and 8 during post-monsoon season. The anomalous cyclonic circulation at lower levels over central and north Bay of Bengal in association with MJO at phase 4 and 5 favours enhanced probability of cyclogenesis over the Bay of Bengal during monsoon season. The anomalous easterlies in association with MJO at phase 1 and development of anomalous ridge over south India in association with MJO at phase 7 and 8 which are weak monsoon features lead to suppressed cyclogenesis over north Indian Ocean during this season. The anomalous north-south trough in easterlies embedded with cyclonic circulation over the south west/west central Bay of Bengal in association with southerly surge over the region during active MJO in phase 3 and 4 most favourably influences the convection and enhances the probability of cyclogenesis over the north Indian Ocean during post-monsoon season. The genesis of CDs is more sensitive to phase than the amplitude while the intensification of CDs is more dependent on the amplitude of MJO. Comparing monsoon and post-monsoon seasons, the modulation of genesis, intensification and duration of CDs by the MJO is more during the monsoon season than the post-monsoon season.

6 illus, 4 tables, 22 ref

016839   Mazumdar A B;Khole M;Sunitha Devi S (NO, Meteorological Office, Pune-411 005) : Post monsoon season (october-december 2010). Mausam 2011, 62(4), 673-706.

2 illus, 10 tables, ref

016838   Mazumdar A B;Khole M;Sunitha Devi S (NO, Meteorological Office, Pune-411 005) : Weather in India monsoon season (June to September 2010). Mausam 2011, 62(3), 463-512.

12 illus, 19 tables, 2 ref

016837   Mazumdar A B;Khole M;Sunitha Devi S (NO, Meteorological Office, Pune-411 005) : Cyclones and depressions over the North Indian ocean during 2010. Mausam 2011, 62(3), 287-304.

9 illus, 3 tables

016836   Kushtagi S;Srinivas P;Patil S G (Civil Engineering Dep, P.D.A. College of Engineering, Gulbarga, Karnataka, Email: srinivaskushtagi@yahoo.co.in) : Regression analysis of ground water of Afzalpur and Jewargi talukas of Gulbarga district, Karnataka (India). Int J chem envir pharm Res 2012, 3(1), 35-41.

Ground water samples from different villages of Afzalpur and Jewargi talukas of GULBARGA District of Karnataka India have been analyzed for various water quality constituents and correlation coefficients among different parameters were determined. An attempt has been made to develop regression equations to predict the concentration of water quality. The usefulness of these equations in predicting the ground water quality is discussed.

4 illus, 6 tables, 11 ref

016835   Khare N (Ministry of Earth Sciences, CGO Complex, New Delhi-110 003) : Influence of solar activity on climate:poles to tropics. Mausam 2011, 62(4), 653-8.

Solar activities are directly or indirectly responsible for climate variability around the globe. Evidences of such correspondences between solar activities and palaeoclimatic proxy data have been reported from polar as well as tropical regions, suggesting solar influence over climate dynamics. However, these findings need to be further strengthened by covering vast geographical region for generating palaeoclimatic data and corresponding variations in solar activities. A better time control on proxy data is essential to arrive at conclusive understanding and plausible causal linkages between solar activity and climate changes from poles to tropics.

3 illus, 19 ref

016834   Khan J H;Shamshad;Hassan T (Geography Dep, Aligarh Muslim Univ, Aligarh-202 002) : Determinants of rural to urban migration of male population in India. Ann Natn Ass Geogr 2011, 31(1), 51-65.

The study aims to analyse the socio-economic causes of rural to urban migration of male population in the age-group of 15 to 39 years and whose duration of residence was one to four years, among the states and union territories of India. According to the migration data of all durations recorded on the basis of place of last residence in the Census of India 2001, the proportion of migrant population in general population was 30.57 per cent while the respective figures for male and female migrants were recorded 17.54 per cent and 44.54 per cent. The share of rural-urban migration to total migrant population was 16.43 per cent, whereas, the percentage of male migrants to total male migrant population was 26.24 per cent and proportion of female migrants to total female migrants population was 12.28 per cent. The ratio of total rural-urban migrants, whose duration of residence was one to four years, was recorded 21.43 per cent to the general migrants of same duration, the corresponding figures for male and female migrants were 31.07 per cent and 16.23 per cent respectively.

3 illus, 1 table, 28 ref

016833   Jain S L (Radio & Atmospheric Sciences Div, National Physical Laboratory, New Delhi-110 012, Email: sljain@nplindia.ernet.in) : Ozone hole over poles: current status. Mausam 2011, 62(4), 577-84.

The ozone in the stratosphere is of great importance for very survival of life on the mother planet the Earth. Ozone acts as an umbrella and protects us from the harmful ultraviolet radiations coming from the Sun. The catalytic destruction of ozone by ClOx & NOx in general and ozone hole phenomenon over Antarctica during spring time in particular has generated unprecedented interest in monitoring of ozone and other trace constituents in the atmosphere. The satellites have proved to be an important tool to monitor the global ozone column on regular basis. The ozone data using various satellite platforms has been analyzed for the ozone hole studies over north and south poles. Also Ozone measurements were carried out at Maitri, Antarctica. The satellite data indicates that some recovery of ozone hole as a result of international efforts in reduction of use of CFCs which are the main culprit for ozone hole. However, it will be too early to conclude about ozone hole recovery. In the present communication current status of ozone hole will be discussed in detail.

6 illus, 22 ref

016832   Hosalikar K S;nair S;Krishnamurthy R (NO, Regional Meteorological Centre, Mumbai) : Short term characterisation of wind and temperature over maitri, East Antarctica. Mausam 2011, 62(4), 567-76.

Polar Science is gaining increased importance in Climate Change studies because of the profound influence Polar Climatology has on the Global Climate. Research shows that Antarctica seems to be warming around the edges and cooling at the center at the same time. East Antarctica is chimatologically colder than west Antarctica because of its higher elevation. A short term characterization of wind and the temperature over Maitii is attempted in this paper. Maximum and Minimum temperatures showed a tendency to decrease with winter contributing the most to the change. The Wind Directions were predominantly South-South-Easterly in summer and autumn and South-Easterly in winter and spring, with katabatic winds showing the maximum frequency in autumn. The wind speeds were found to be most variable in winter. Greater contributions to the wind chill temperatures were found from the winds, with the tendency for change being more prominent in the transition seasons.

7 illus, 1 table, 10 ref

016831   Gusain H S;Mishra V D;Negi A (Snow and Avalanche Study Establishment, Research and Development Centre, DRDO, Chandigarh-160 036, Email: gusain_hs@yahoo.co.in) : Comparative study of the radiative and turbulent energy fluxes during summer and winter at the edge of the Antarctic ice sheet in dronning maud land-east antarctica. Mausam 2011, 62(4), 557-66.

Present study compares the estimated radiative and turbulent energy fluxes at the edge of the Antarctic ice sheet during summer and winter in Dronning Maud land, East Antarctica. Hourly snow meteorological parameters were recorded and analysed during winter months (May, June, July and August) of the year 2007 and summer months (November, December, January and February) of the year 2007-08 using Automatic Weather Station (AWS) on the glacier surface. Snow-meteorological parameters air temperature, relative humidity, wind speed, wind direction, incoming solar radiation, outgoing solar radiation, atmospheric pressure and glacier surface temperature were recorded by the AWS. An energy balance model was used to evaluate the surface energy fluxes from measured meteorological quantities for the summer and winter. Net radiative flux was observed the main heat source during summer with seasonal average of 98Wm^-2 while sensible heat flux was observed main heat source during winter with seasonal average of 30 Win^-2. Latent heat flux was observed the main heat sink during both the season with seasonal average values of -86.7 Wm^-2 for summer and -65.4 Wm^-2 during winter. Sublimation was observed high during summer compare to winter.

9 illus, 17 ref

016830   Ganesh K E;Umesh T K;Narasimhamurthy B (S&H Bengaluru Dep, PES Institute of Technology, India, Email: ganeshke@gmail.com) : Variation of aerosol optical thickness with atmospheric water vapour : a case study over a continental station Mysore, India. Mausam 2011, 62(3), 441-8.

Atmospheric measurements in a continental, low latitude station Mysore (12.3° N) has been carried out, for the period December 2003 to June 2006. Measurements were made using a sunphotometer with five bands in the visible and near-infrared range of the solar spectrum. To bring out the wavelength dependence of Aerosol Optical Thickness (AOT) on atmospheric water vapour, typically two wavelength channels are being used, one at 500 mn and the other at 1020 nm. A linear dependence between AOT and water vapour on meteorologically calm days is the important observation made. Growth rate of AOT is found to be larger at shorter wavelength (500 nm) than that of the longer wavelength (1020 nm). A mass-plot representation is followed on monthly basis, which is nothing but the graphical plot of spectral AOT versus water vapour of the scans for all the clear sky days of a particular month. Further investigations reveal that some months exhibit a single trend of growth of AOT with water vapour whereas double trend is the scenario for other months. These results provide insight into the changes in the atmospheric aerosol characteristics with precipitable water vapour, which is the subject matter of this paper.

10 illus, 3 tables, 15 ref

016829   Gajendra Kumar;Madan R;Saikrishnan K C;Kundu S K;Jain P K (NO, India Meteorological Dep, New Delhi, Email: gkumarimd@yahoo.com) : Technical and operational characteristics of GPS radiosounding system in the upper air network of IMD. Mausam 2011, 62(3), 403-16.

In recent years, the upper air radiosounding system based on Global Positioning System (GPS) is used as an effective method. GPS receiving device in a Radiosonde improves observation accuracy, allowing simplification of ground equipment. To get improved quality of upper air data, ten stations have been upgraded with new upper air systems based on GPS. This paper describes the upper air radiosounding system that adopts the GPS. After the introduction of GPS Radiosonde in the network at 10 places, data quality has improved substantially at these stations, which has been validated by National Centre for Medium Range Weather Forecasting (NCMRWF) and European Centre for Medium-Range Weather Forecasts (ECMWF). In all cases the quality change has been remarkable and as a result black list tag is removed by ECMWF for the Indian GPS stations.

7 illus, 4 tables, 3 ref

016828   Duraisamy M;Roy Bhowmik S K;Bandyopadhya B K (NO, India Meteorological Dep, New Delhi, Email: duraisamy.imd@gmail.com) : Objective method for predicting occurrence of pre-monsoon (March-May) thunderstorm events over Delhi using stability indices. Mausam 2011, 62(3), 329-38.

In this paper an attempt has been made to investigate different stability indices in relation to the occurrence of thunderstorms in order to determine the critical values of these indices for Delhi (28.35° N/77.12° E) using pre monsoon data for the years 1999 - 2004. The study shows that the critical values of Showalter Index (SI). Lifted Index (LI), K Index (KI), Total Totals Index (TTI), and Sweat Index (SWI) are respectively <60> 2 °C, <60> 0 °C, <62> 24 °C, <62> 44.5 °C and <62> 100 for the thunderstorm to occur over Delhi. The corresponding common critical ranges of Lifted Condensation Level (LCL), Level of Free Convection (LFC), Equilibrium Level (EL) and Precipitable Water (PW) are respectively 923 hPa - 695 hPa, 856 hPa - 504 hPa, 545 hPa - 109 hPa and 18 mm - 54 mm. Testing of critical values of indices and the corresponding common critical ranges of LCL, LFC, EL and PW during pre-monsoon seasons of the years 2005 and 2006 shows that they are matching well with the respective critical values/ranges in most of the thunderstorm days.

9 tables, 27 ref

016827   Devappa V M;Khageshan P;Mise S R (NO, , R.E.C. Bhalki, Dist. Bidar, Karnataka, Email: vmdevapa@gmail.com) : Long term assessment of southwest monsoon drought events at taluka levels in Gulbarga district of Karnataka. Mausam 2011, 62(3), 449-56.

9 illus, 1 table, 14 ref

015694   Yadav J K S;Giri R K;Meena L R (NO, India Meteorological Dep, New Delhi-110 003, Email: jksmet@gmail.com) : Error handling in GPS data processing. Mausam 2011, 62(1), 97-102.

Processing of GPS data through GAMIT processing software is not free from errors. Some of them are generated due to different modules involved in processing. The data quality depends so many factors, like quality of met-instrument, which supplies the meteorological data, algorithm of processing which based on the network homogeneity or heterogeneity and location of the site, whether it is free from multi-path etc. The root mean square errors for New Delhi, Mumbai, Kolkata, Guwahati and Chennai GPS stations are spatially correlated and observations are weighted according to the satellite elevation angle. Diurnal variability of Integrated Precipitable Water Vapour (IPWV) has been shown its range from 45 mm to 65 mm for New Delhi during the monsoon season, 2008.

16 illus, 1 table, 8 ref

015693   Verma I J;Das H P;Jadhav V N (NO, Meteorological Office, Pune, Email: ijverma2@yahoo.co.in) : Recent changes in monthly, seasonal and annual evaporation at selected locations in India. Mausam 2011, 62(1), 111-18.

2 illus, 3 tables, 12 ref

015692   Tomar M S (NO, Meteorological Office, Patiala) : Trends of pH and aerosols in the precipitation at Srinagar, Mohanbari, Allahabad, Jodhpur, Nagpur, Minicoy during the period 1981-2001. Mausam 2011, 62(2), 235-8.

Nature of Precipitation - alkaline or acidic depends upon the concentration of major water soluble inorganic gaseous and soil derived particulates dissolved in it. If the concentration of cations is higher than that of anions the precipitations becomes alkaline and vice versa. pH is the mam parameter indicating the nature of precipitation. If pH of rainwater <60>5.65 it is acidic and <62>5.65, it is alkaline, both in the pH scale ranging between 0 and 14. In this paper average ionic concentration (mg/lit) and their trends have been analyzed. Srinagar, Mohanbari, Jodhpur, Allahabad, Nagpur and Mimcoy have been selected for the study of chemical precipitation during the period 1981-2001. Trends of different aerosols have been analyzed at the intervals 1981-87, 1988-94 and 1995-2001. It has been observed that percentage of anions has increased which results in the increase of acidic character of the precipitation. During the interval 1995-2001, Nagpur and Mohanbari had pH values 5.16 and 5.47 respectively which were in acidic range.

1 illus, 3 tables, 6 ref

015691   Tejpal;Sharma M;Jaglan M S (Geology Dep, Kurukshetra University, Kurukshetra-136 119, Email: tpjangid@gmail.com) : Significance of geospatial technology and status of its education and training in India. Int J Geomatics Geosci 2012, 2(3), 730-7.

In the era of information technology with rapid advancement in computing, decision making has become more informed and scientific and in this field Geospatial Technology has emerged strongly with diverse applications. It has been identified as one of the three most important emerging fields along with nanotechnology and biotechnology because of providing unbiased, reliable, repetitive and synoptic nature of data as well as tools for integration of information for analysis, which is very useful in the management and monitoring of natural resources. There is requirement of trained and skilled personnel for the maximum potential exploration of this technology and also need to introduce it in education system for its wider understanding. There is also a need of well thought of plans for broader acceptability and awareness regarding geospatial technology for development of human resource through training and education. Discusses the necessity of formal education in the field of Geospatial Technology in India with respect to existing programmes and facilities provided by various institutions in the country.

2 illus, 3 tables, 16 ref

015690   Surinder Kaur;Das A K (NO, India Meteorological Dep, New Delhi-110 003, Email: surinder57.kaur@imd.gov.in) : Catastrophic floods in Kosi catchment during August 2008. Mausam 2011, 62(1), 21-6.

Breach in embankment of Kosi barrange was reported on 18 August, 2008 which has changed its course and resulted in a fresh channel around 120 km to the east of its previous channel. At the time of failure of the embankment, gushing out of about 2832 m³/s water with great impact breaking into the Mahendra Rajmarg and then taking a southward route into the old 1892-1921 abandoned course of the river, thus leaving the pre-breach C-loop and following a straight route to the Ganga. In the study meteorological aspect are analysed in details in relation to the catastrophic flood in the Kosi river catchment during August 2008. It seems that this catastrophic flood may not be solely due to rainfall in the catchment of Kosi. The breach is due to incorrect strategies of river management, human negligence and poor maintenance of afflux bund of the barrage.

5 illus, 2 tables, 7 ref

015689   Sunitha V;Muralidhara Reddy B;Jagadish Kumar M;Ramakrishna Reddy M (Geology and Geoinformatics Dep, DST, Yogi Vemana University, Vemanapuram, Kadapa-516 003, Email: vangala_sunitha@yahoo.com) : GIS based groundwater quality mapping in southeastern part of Anantapur district, Andhra Pradesh, India. Int J Geomatics Geosci 2012, 2(3), 805-14.

Groundwater is used for domestic, industrial water supply and for irrigation all over the world. Although three-fourth of earth is being surrounded by sea only a little portion of it can be used for drinking purpose. The study area lies in the Southeastern part of Anantapur District, Andhra Pradesh. The area is located in the survey of India toposheets No's 57 F/14, F/15, J/3, J/4 lying between east 77030' - 78015' longitudes and 1400' - 14030' North latitudes. Geologically, it is underlain mainly by Peninsular gneisses of Archean age and comprises pink granites, schists and composite gneisses (equivalents of the Dharwars), intruded by a few pegmatite dykes. Major geomorphic units are denudational hills, dissected pedimonts, pediplain and alluvium. The study area experiences a semiarid climate. The study area faces water scarcity as well as water quality problems. Hence, a Geographic Information System (GIS) based assessment of spatiotemporal behaviour of groundwater quality has been carried out in the region. A surface map was prepared in the Arc GIS 9.3 (spatial analyst module) to assess the quality in terms of spatial variation and it showed that the high and low regions of water quality varied spatially during the study period. All the other parameters analysed are in adherence to desirable limits of WHO and Indian Standards for drinking water. Hence the groundwater in the study area is not suitable for drinking purpose. The spatial analysis of groundwater quality patterns of the study area shows seasonal fluctuations and these spatial patterns of physical and chemical constituents are useful in deciding water use strategies for various purposes.

6 illus, 2 tables, 16 ref

015688   Sudeesh S;Sudhakar Redddy C (NO, Indian Institute of Information Technology and Management - Kerala, Thiruvananthapuram, Email: sudeeshes@gmail.com) : Vegetation and land cover mapping of Nagarjunasagar-Srisailam Tiger Reserve, Andhra Pradesh, India using remote sensing and GIS. Int J Geomatics Geosci 2012, 2(4), 963-73.

Mapping of vegetation and land cover is important for managing natural resources. Remote sensing plays a vital role in mapping of existing land resources information at a particular period. The study area Nagarjunasagar-Srisailam Tiger Reserve (NSTR) is the largest tiger reserve of India, situated in the state of Andhra Pradesh. Multi-season IRS P6 LISS III data of 2010 was used to map the vegetation types and other land cover. Of the digital classification techniques, supervised classification and maximum likelihood algorithm were used in the study. Results indicate the forest cover as 2653.9 km² and which is proportionately 61% of the total geographic area of NSTR. The interpretation of images and GIS analysis indicates that the open dry deciduous forest is the most dominant vegetation type comprising 52.5% (1394.3 km²) of the total forest stock in 2010. The study is helpful in assessing and quantifying the land cover of NSTR and this information can be used for monitoring status of forests.

4 illus, 4 tables, 19 ref