013487   Vashistha R D;Mohan K N;Biju P S (NO, India Meteorological Dep, Pune, Email: ramdhanvashistha@yahoo.co.in) : Indigenous state-of-the-art High Wind Speed Recording (HWSR) system for coastal meteorologial observatories. Mausam 2010, 61(3), 361-8.

The continuous and accurate monitoring of wind speed and direction is of utmost importance to weatherman, particularly during the cyclonic storms. Wind monitoring also helps the meteorologists in tracking the cyclone accurately and estimating their devastating potential. One major disadvantage of all the existing wind monitoring and storing systems is their huge consumption of power, and hence are not suitable during cyclonic storms due to mains power supply failure. So an attempt has been made by the authors to design and develop a low cost, low power, more accurate and maintenance free High Wind Speed Recording (HWSR) System for the coastal meteorological observatories along the East and West Coasts of India. One such system after successful field trials have been installed at Meteorological Office, Puri in the Orissa coast, and 19 more stations are proposed along East and West Coasts of India. The system meets the operational accuracy requirements and vector averaging of wind data as recommended by the World Meteorological Organisation (WMO, 1992). The system design aspects and scope for expansion have been presented in this paper.

8 illus, 1 table, 4 ref

013486   Vashist M;Yadav R;Neelkamal Rathee R;Sharma S (Genetics Dep, M.D. Univ, Rohtak, Haryana) : Dermal patterns of Haryana population. Natn J Life Sci 2010, 7(1), 63-5.

Dermatoglyphics is the analysis of finger prints, palm prints, atd angle, sole and toe prints of a particular individual. The variation in the dermatoglyphics of population can be a tool to analyze the genetic make up and any deviation will be a strong indicative of inherited abnormality or altered genotype. Present study has been undertaken on 500 normal individuals of Haryana state. Prints of fingers, palm, sole and toes were taken with the help of Indian ink method. The dermatoglyphics has been analyzed and compared with the existing literature. Digits of finger prints showed highest frequency of ulnar loop pattern (57.08%), where as whorls and arch patterns were 37.3% and 3.4% respectively. Frequency of radial loop was only 3.7%. Toe configuration showed loop fibular and simple whorl more frequently. Hallucal area of sole revealed 54.5% loop distal pattern. Arch fibular and arch tibial patterns were not seen in any case. Remarkably the atd angle was in the range of 35? - 40? in the maximum number of cases. The present study of dermatoglyphics of normal individual will play a significant role in the clinical diagnosis of various congenital disorder and we can say that any deviation from the normal range will provide a clue of certain genetic disorder. The result can be used for the purpose of identification of populations and in anthropology.

4 illus, 5 tables, 12 ref

013485   Thakur B R;Sharma D D (Geography Dep, Himachal Pradesh Univ, Shimla) : Development of infrastructure in tribal areas of Himachal Pradesh-a geographical analysis. Trans Inst Indian Geogr 2010, 32(1), 93-104.

The Kinnaur and Lahaul-Spiti districts, in their entirety, and Pangi and Bharmaur Sub-Divisions of Chamba district are notified tribal areas in the state and inhabited by different scheduled tribal communities. The present study is based on secondary data. The secondary data relating to indicators of socio-economic infrastructural development at the village level have been gathered from District Census Handbooks, Directorate of Census Operations, Shimla. The development of infrastructure has been studied at the village level for the periods 1971 to 2001. The present study is based on the analysis of 681 inhabited villages of 2001 census. In 1971 the number of inhabited villages was 484. The present study is an attempt to evaluate the trends in the level of development of social and economic infrastructure in the study area. In order to examine the level of infrastructural development six sectoral indicators which include education, health, drinking water, banking, electrification and communication have been computed at the village level. A composite index of these six sectors of infrastructure has been computed by assigning the weightage to different facilities according to their importance in socio-economic development of rural areas. The spatial variations in the level of infrastructural development have been shown with the help of choropleth maps. The study reveals that there has been a considerable expansion in infrastructural facilities across different tribal areas of Himachal Pradesh over the period 1971 to 2001. But the values of composite weighted score, representing all basic facilities has increased for all the inhabited villages in the region and across the areas during next three decades. However, there is a large scope for improvement in the remote and inaccessible villages regarding infrastructural development.

4 illus, 1 table, 4 ref

013484   Taid M;Lyngdoh A C;Ghose A K (Central Seismology Observatory, India Meteorological Dep, Shillong, Email: lyngdoh_ac@rediffmail.com) : Determining earthquake epicentre from a single 3-component seismological station. Mausam 2009, 60(1), 81-8.

An attempt has been made in this study to determine the epicentres by trigonometrical method from a single station using the three components of the ground's motion recorded by the Benioff Short Period Seismograph of the World Wide Standardized Seismograph Network (WWSSN) at Central Seismological Observatory (C.S.O.), Shillong. The trigonometrical method is based on the angle of bearing obtained from the ratio of the amplitudes of waves recorded on the horizontal components of the WWSSN seismograms. A comparison of recorded epicentres from the I.M.D. Seismological Network of Seismo, New Delhi with that of a single station i.e., C.S.O., Shillong has been made to estimate the accuracy of the method. The characteristics of the epicentral variations obtained from the Seismological Network of Seismo, New Delhi with that of C.S.O., Shillong are relatively small for local earthquakes compared to regional earthquakes with C.S.O., Shillong as the reference station. The characteristics of the epicentral variations particularly in the Shillong plateau are observed to be minimum. Strong correlations of epicentres are observed for both local as well as regional earthquake events.

4 illus, 1 table, 10 ref

013483   Suresh R (NO, India Meteorological Dep, Chennai, Email: suresh.imd@gmail.com) : Account of low level wind shear over Chennai airport .II. Turbulence and eddy dissipation. Mausam 2009, 60(3), 325-42.

In-flight reports on Low Level Wind Shear (LLWS) received from aircrafts are used to issue wind shear alerts for all subsequent landing aircrafts as per standing guidelines of International Civil Aviation Organisation (ICAO). In this paper, winds reported by aircrafts at 1000 and 1800 ft. are used to validate the wind estimated from DWR measured radial wind data employing standard algorithms. Turbulence indices and parameters have been computed independently using conventional (RS/RW) upper air data, aircraft measured winds and DWR estimated winds and compared these with wind shear induced turbulence reported by aircrews. Mean power law (wind escalation law) profiles in the boundary layer have been arrived at for unstable and stable atmospheric conditions. Three dimensional shear (3DS) upto 600 m a.g.l. has been worked out from DWR measured radial velocity data and compared with wind shear computed from RS/RW and aircraft measured winds and DWR estimated winds. It is found that 3DS values of more than 16 * 10^-3 s^-1 predict well the occurrence of moderate turbulence. Contrary to the general belief that wind shear is a short lived phenomenon which may last for a few minutes only, it has been observed that incidences of LLWS and induced moderate turbulence lasting more than 10 hrs are not at all uncommon over Chennai aircraft.

7 illus, 4 tables, 36 ref

013482   Srivastava K;Roy Bhowmik S K;Hatwar H R (NO, India Meteorological Dep, New Delhi, Email: kuldeep.nhac@gmail.com) : Evaluation of different convective schemes on simulation of thunderstorm event over Delhi by ARPS model. Mausam 2009, 60(2), 123-36.

Three difference cumulus parameterization schemes namely, Kain-Fritsch, New Kain-Fritsch and the Betts-Miller-Janjic are used to simulated convective rainfall associated with two thunderstorm events over Delhi by Advanced Regional Prediction Model (ARPS). An inter comparison of model simulated precipitation in respect of each convection scheme is made with reference to observed precipitation. The study shows that for the Delhi thunderstorm events, the Kain-Fritsch scheme provides more realistic results. This scheme is able to capture the temporal distribution of rainfall and the timely development of thunderstorm in both the cases. While the other two schemes fail to capture these features. However, the Kain-Fritsch scheme is found to overestimate the rainfall amount.

9 illus, 5 tables, 15 ref

013481   Singh P K;Rathore L S;Singh K K;Baxla A K; Athiyaman B (Min. of Earth Sciences, National Centre for Medium Range Weather Forecasting, Noida, Email: pksingh66@gmail.com) : Incomplete gamma distribution of rainfall for sustainable crop production strategies at Palampur, Himachal Pradesh. Mausam 2009, 60(1), 73-80.

The knowledge of rainfall pattern (amount and probability) helps in planning of crops to be grown in a region. Therefore weekly, monthly, seasonal and annual rainfall data for 33 years (1974-2006) for the station Palampur have been collected and its analysis has been attempted. The annual and monthly rainfall data were analyzed for finding out drought normality and abnormality. The analysis indicated that the rainfall is mainly confined in annual rainfall 2343 mm with 25.7 per cent variability. The standard deviation of annual rainfall is 62.8 mm. Each standard week from 26th to 35th receive a rainfall of more than 100 mm, indicating the crop period. Seed sowing in paddy nursery in the Palampur region generally takes places immediately after initiation of monsoon during 23rd - 25lh standard meteorological weeks and transplanting is carried out around 27th or 28th standard meteorological week. The tillering, 50 percent flowering and dough stage are observed during 32-33rd, 37-38th and 40-41st standard meteorological weeks respectively.

2 illus, 4 tables, 8 ref

013480   Singh P K;Rathore L S;Athiyaman B;Singh K K; Baxla A K;Ashok Kumar;Bhargava A K (NO, India Meteorological Dep, New Delhi-110 003, Email: pksingh@ncmrwf.gov.in) : Frequencies of drought at Ranchi regions, Jharkhand. Mausam 2009, 60(4), 455-60.

Studies of water balance have been carried out for Ranchi taking 35 years (1970-2004) of climate data. Ranchi has annual water need of 1754 mm, rainfall of 1460 mm, actual evapotranspiration (AE) of 860 mm, water surplus (WS) of 600 mm and water deficit (WD) of 894 mm. The aridity index values were analyzed to assess the frequency of drought experienced of this region. The study reveals that during the above period, Ranchi has experienced 11 percent of large drought and severe drought, but only 3 per cent disastrous droughts in 35 years. Moderate drought category is observed to be most common with 23 per cent probability. Analyses of periods will contagious drought indicate that during the five year period 1980-84 and 1995-99, moderate, large and severe droughts were experienced.

3 tables, 10 ref

013479   Singh O P (NO, India Meteorological Dep, New Delhi, Email: opsingh@imdmail.gov.in) : Simulations of frequency, intensity and tracks of cyclonic disturbances in the bay of Bengal and the Arabian sea. Mausam 2009, 60(2), 167-74.

Presents the results of simulation experiments conducted for the assessment of likely changes in the cyclogenesis pattern in the Bay of Bengal (BOB) and the Arabian Sea (AS) resulting from global climate change. Two experiments were performed, namely the 'control' (CTL) experiment in which the greenhouse gas concentration in the atmosphere was fixed as per 1990 levels and the 'greenhouse gas' (GHG) experiment in which an annual compound increase of 1% from 1990 onwards was introduced. CTL and GHG experiments of 20 years length were performed for the period 2041-2060. The model used is the regional climate model Had RM2 of the Hadley Centre of Climate Prediction and Research, U.K. The results have brought out some significant changes in the cyclogenesis pattern in the North Indian Ocean (BOB and AS). The most significant likely change is the increase in the frequency of post-monsoon storms in the Bay of Bengal. The experiments show an increase of about 50% in the post-monsoonal cyclogenesis by 2041-2060 as a result of increased greenhouse gas concentrations in the atmosphere. The frequency of monsoon depressions/storms in the BOB is likely to decrease considerably during June-August. Due to varying impacts in different seasons, the annual frequency of cyclonic disturbances may change marginally in the BOB. In the Arabian Sea, however the model has simulated a significant reduction in the frequency which may be halved by the period 2041-2060.

3 illus, 2 tables, 11 ref

013478   Singh K M;Prasad M C;Prasad G (NO, , Shanti Kunj, Mausam Colony, Patna, Email: krishnamurari@yahoo.com ) : Semi quantitative forescasts for Bghmati/Adhwara group of rivers/kamala balan catchements by synoptic analogue technique. Mausam 2010, 61(3), 337-48.

An attempt has been made to issue semi-quantitative precipitation forecasts for Baghmati/Adhwara Group of rivers/Kamala-Balan catchments based upon 22 years data (1982-2003). The study reveals that it is possible to issue semi-quantitative precipitation forecast with confidence. Local topography and its steep gradient on Indo-Nepal Border are main factors that give birth to severe floods during south west monsoon and pose problems to Darbhanga City.

4 illus, 4 tabls, 8 ref

013477   Sharma N;Dash M K;Pandey P C;Vyas N K (NO, Indian Institute of Technology, Kharagpur-721 302, Email: mihir@coral.iitkgp.ernet.in) : Hemispheric sea ice extent dynamics as observed from MSMR. Mausam 2009, 60(3), 295-308.

The ice covered regions of the polar seas influence the global climate in several ways. Any perturbation in the polar oceanic cryosphere affects the local weather and the global climate through modulation of the radiative forcing, the bottom water formation and the mass & the momentum transfer between Atmosphere-Cryosphere-Ocean System. The cold, harsh and inhospitable conditions in the polar regions prohibit the collection of extensive in situ data with sufficient spatial and temporal variation. However, satellite remote sensing is an ideal technique for studying the areas like the polar regions with synoptic and repetitive coverage. This paper discusses the analysis of the data obtained over the polar oceanic regions during the period June 1999 - September 2001 through the use of Multi-channel-Scanning Microwave Radiometer (MSMR), onboard India's first oceanographic satellite Oceansat-1. The MSMR observation shows that all the sectors in the Antarctic behave differently to the melting and formation of the sea ice. Certain peculiar features like the increase in sea ice extent during the melt season of 1999 - 2000 in the Indian Ocean sector, 15-20% decrease in the sea ice extent in the western Pacific sector during the ice formation period for the year 2000, melting spell within the formation phase of sea ice in B & A sector in the year 2000 were observed. On the other hand the northern polar sea ice extent is seen to be more dominated by the land characteristics. The ice formation in Kara and the Barent Sea sector is dominated by the ocean currents, where as the ice covered in the Japan and the Okhotsk Sea is dominated by the land processes. The sea ice extent in the Arctic Ocean show fluctuations from July to October and remain almost steady over other months. The global sea ice cover shows a formation phase from March to June and melting phase from November to February. In other months, i.e., from July - October the global sea ice cover is dominated by the hemispheric asymmetry of the ice growth and retreat.

6 illus, 3 tables, 16 ref

013476   Sayadi M H;Torabi S (Environmental Science Dep, Pune Univ, Pune-411 007) : Geochemistry of soil and human health : a review. Pollut Res 2009, 28(2), 257-62.

Soil contamination is caused by the presence of man-made chemicals or other alteration in the natural soil environment. The contamination of the top soil is serious from the standpoint of its direct impact on human health. This pollution consists mainly of contamination by toxic metals in connection with emissions from industry and transportation. Metals maybe inhaled as dust and also ingested involuntarily through food and drink as well as would be absorbed through skin. Metals are notable for their wide environmental dispersion from such activity; their tendencies to accumulate in select tissues of the human body, and their overall potential to be toxic even at relatively minor levels of exposure. Some metals do not play any role in human body and some others as in the case lead, cadmium, mercury are toxic even at trace levels and also essential metals could be harmful at very high levels. The toxicity of metals commonly involves the brain and the kidney, but other manifestations occur. This paper focuses on exposure to the heavy metals lead, mercury, arsenic, cadmium, chromium etc. as they are arguably the most important metal toxins from a world as well as some additional remarks are also made regarding a few other metals of concern.

60 ref

013475   Roy Bhowmik S K;Nath S;Mitra A K;Hatwar H R (NO, India Meteorological Dep, New Delhi, Email: skrb.imd@gmail.com) : Application of neural network technique to improve the location specific forecast of temperature over Delhi from MM5 model. Mausam 2009, 60(1), 11-24.

India Meteorological Department (IMD) has been using direct model output (2 meters height temperature) of MM5 model as numerical guidance for forecasting maximum and minimum temperature of Delhi in short range time scale (up to 72 hours). Performance statistics of the direct model outputs of the model for maximum and minimum temperature show that forecast skill of the model is reasonably good, particularly for the minimum temperature. For further improving the model forecast, Neural Network (NN) as well as regression techniques are applied so that the systematic errors of the direct model output of the model for maximum and minimum temperature could be reduced. The study shows that both Neural Network approach and regression technique are capable to improve the forecast skill of maximum and minimum temperature. Daily modified forecasts are found persistently closer to the observations when the method is tested with the independent sample. The methods are found to be promising for operational application.

7 illus, 4 tables, 17 ref

013474   Reghunath R;Bijo Sekhar S;Nithin R;Binoj Kumar R B (Geology Dep, University of Kerala, Kariavattom Campus, Tirivandrum-695 581) : Demarcation of groundwater prospective zones in a degraded region of western ghats: a GIS based approach. Nat Envir Pollut Technol 2009, 8(2), 347-50.

Attappady region in the Palghat district of Kerala is one of the severely degraded areas in the Kerala Western Ghats. Apart from the severe ecological, socioeconomic, political and cultural problems, the region faces an acute water scarcity too. By identifying the severe ecological degradation and the consequent sociological problems, a watershed based massive ecorestoration project has been initiated in Attappady by the State government. The present study carried out in this area deals with the identification of groundwater potential zones. The groundwater potential zones of Attappady area generated from this study identifies five zonesªvery high, high, moderate, low and very low. The groundwater potential map generated in this study by making use of GIS tools will be useful in narrowing down the target areas for ground resistivity surveys in order to pinpoint the prospective well site. The results of this study can be used in the ongoing ecorestoration project at Attappady.

2 illus, 4 ref

013473   Rathore D K (Botany Dep, Governemnt College, Bundi, Rajasthan) : Effects of linear alkyl benzene sulphonate on physiology of Nostoc muscorum ag. ex born et flah. Natn J Life Sci 2010, 7(1), 21-2.

Cyanobacteria are prokaryotic organisms with oxygen evolving photosynthetic as well as dinitrogen fixation property. Algae are known for their ability to degrade and use organic substances (natural or synthetic) as source of nutrients or very rarely for energy. Linear alkyl benzene sulphonate (LABS) is an anionic biodegradable surfactant. The effects of selected concentrations (3, 10 and 15 ppm) of LABS on different growth parameters of Nostoc muscorum have been examined in terms of total carbohydrate, protein, amino acids, pH, total dissolved solids (TDS) and electrical conductivity (EC).

2 tables, 12 ref

013472   Rase D M;Shevale M P;Rizvi S I M (NO, Meteorological Dep, Pune-411 005, Email: dineshmrase@rediffmail.com) : Secular variations and trends in the occurrence of monsoon synoptic systems and its impact on central India rainfall. Mausam 2009, 60(3), 309-16.

Importance of monsoon depressions, Low Pressure Systems (LPS) and the number of LPS days on rainfall and hence indirectly on agriculture and hydrology, is well recognized. In this paper the pattern of annual variability in these systems have been examined using data from 1901-2000. The above mentioned parameters have been subjected to decadal analysis to detect presence of any regular pattern. An attempt has been made to find its tendency with time. Impact of these systems on central India rainfall has been determined and discussed. The study endorses the earlier findings that there is a decreasing trend in the frequency of depressions which has been compensated with increase in LPS days over Indian region in recent years. The rainfall over central India is more significantly related with a number of LPS days over Indian region.

2 illus, 2 tables, 22 ref

013471   Raj Y E A (NO, Regional Meteorological Centre, Chennai, Email: yearaj@gmail.com) : Relation between pressure defect and maximum wind in the field of a tropical cyclone - theoretical derivation of proportionality constant based on an idealised surface pressure model. Mausam 2010, 61(3), 291-316.

The surface pressure defect ΔP and the surface maximum wind speed V_m of a tropical cyclone which are two important measures for the intensity of a tropical cyclone are related by the well known relation V_m = K√ΔP where K is the proportionality constant. Based on composites of observations of V_m and ΔP within the cyclone field, the empirical values of K have been derived in a large number of studies. The value of K thus derived has been found to vary in the range 10.5-16.0 when V_m and ΔP are measured in knots and hPa respectively. In this study the problem of estimating the value of K has been approached and treated from an entirely different angle. A general idealised pressure model derived using the concept of Pearson's Distributions in Statistical Distribution Theory has been initially assumed. Based on a few logical and acceptable assumptions such as - validity of cyclostrophic balance near the centre of the cyclone, existence of radius of maximum pressure gradient, convergence of integral defining cumulative surface pressure drop, relative vorticity to remain positive up to some distance from the centre, absolute vorticity to remain always positive within the cyclone field - the ranges of variables defining the general pressure model, and hence for K, have been derived without in any way relying upon actual observations of V_m or ΔP. After incorporating frictional forces, environmental flow and force due to translation speed of a tropical cyclone, the final value of K has been derived as 11.0. This theoretically estimated K value compared very well with the empirically derived values but was slightly on the lower side. Apparently most of the empirical K values derived in other studies generated overestimated V_m values for given ΔP and this aspect has been discussed.

7 illus, 4 tables, 30 ref

013470   Raha G N;Bhattacharjee K;Joardar A;Mallik R; Dutta M;Chakraborty T K (NO, Flood Meteorological Office, Jalpaiguri, Email: itsraha@gmail.com) : Quantitative precipitation forecast (QPF) for Teesta basin and heavy rainfall warning over teesta basin & adjoining areas in north Bengal & Sikkim using synoptic analog method. Mausam 2009, 60(4), 491-504.

Presents the method to issue Quantitative Precipitation Forecast (QPF) for Teesta catchment. A synoptic analog model has been developed analyzing 10 years (1998-2007) data for Teesta catchment. The outcomes are then validated with the realized Average Areal Precipitation (AAP) for the corresponding synoptic situations during south-west monsoon season 2008 (1st June to 30lh September) over Teesta basin arid results revealed that there exists a good agreement between day-to-day QPF with corresponding realized AAP calculated over this basin next day. In addition, occurrence of heavy rainfall has also been studied in this paper.

2 illus, 7 tables, 9 ref

013469   Rad S M M;Shankara M;Rad S H M;Shahmoradi B (Geology Dep, University of Mysore, Mysore) : Selecting suitable resin for parting yttrium from leaching solution of Saghand uranium mine in Yazd, Iran. Nat Envir Pollut Technol 2009, 8(2), 313-16.

Gives ion exchange and influence of different types of resins for separating existing yttrium in acid leaching solution of Saghand Mine in Yazd, Iran. Firstly, after doing XRF and ICP experiments on the sample, the resultant solution was assigned out of acid leaching of the region in contact with 0.5 mL resin (based on mass percentage) from different types of anion and cation resins. In each experiment 50 mL of the sample containing 500 ppm yttrium in a column was brought into contact with different types of prevalent resins. The resins were then brought into contact for 15 minutes to different types of elusion solutions. After the analysis the resin Dow x 50w x 8 (W) was selected as the optimum resin in exposure to 1 moll L sodium acetate as the elusion solution with retrieving 93% yttrium.

2 illus, 1 table, 9 ref

013468   Prasad N;Mukherjee I (Geography Dep, Burdwan Univ, Burdwan-713 104, Email: nprasad1947@gmail.com) : Hydrological characteristics and fluvial morphology in the Bhagirathi-Jalangi flood plains of the eastcentral West Bengal. Trans Inst Indian Geogr 2010, 32(1), 11-26.

The Bhagirathi-Jalangi Floodplain lies in the moribund deltaic Bengal where post -Pleistocene alluvial deposits in the foredeep and relatively high amount of rainfall have facilitated for the storage of huge ground water resource. The low gradient on the other hand has facilitated the river Bhagirathi and Jalangi to oscillate their courses over centuries and even over decades within their meander belts as a result of which numerous interesting fluviomorphic features, like bits, ox-bow lakes, cut-offs, palaeochannels etc. have been evolved. Temporal change in the number and spatial variation in the morphology of the bils are also very important. In terms of hydrological characteristics, there is a direct positive relationship between monsoon rainfall and depth of ground water table. Over-exploitation of ground water for increasing irrigation facility and cropping intensity in the study area; influence gradual depletion of water reserve. The present work has been to make an effort to discuss and analyse the fluvial dynamics in the Bhagirathi-Jalangi Floodplains of the Eastcentral West Bengal.

5 illus, 4 tables, 12 ref

013467   Patil C S;Puttanna B (NO, Meteorological Centre, Bangalore-560 001, Email: cspatilmet@rediffmail.com ) : Influence of actual evapotranspiration, growing degree days and bright sunshine hours on yield of finger millet. Mausam 2009, 60(3), 34-8.

Based on the result of an experiment conducted for three years from 1997-1999 during Kharif, under rainfed conditions, a model has been generated for relating crop coefficient of ragi with time at Bangalore. The peak value of crop coefficient was found to be 1.02 on 66'h day after sowing. The multiple regression equation was also generated based on the accumulated values of actual evapotranspiration (AET), growing degree days (GDD) and bright hours of Sunshine (BHS) from sowing to physiological maturity, using the field experimental data for the period 1998-2005. This multiple regression equation can be applied to forecast the yield of finger millet under rainfed conditions. This model was validated for the crop grown during Kharif 2005.

2 illus, 2 tables, 12 ref

013466   Niranjan Kumar K;Reddy A G S;Srinivas Varma K (Geology Dep, Kakatiya Univ, Warangal-506 009, Email: niranjankumarkollipara@yahoo.co.in) : Langelier saturation index for the groundwater of Narayanpur, Nalgonda district, Andhra Pradesh, India. Pollut Res 2009, 28(2), 211-4.

During the course of groundwater quality appraisal of Narayanpur, Nalgonda District, Andhra Pradesh. The hydrochemical data of the area has been subjected to Langelier Saturation Index for evaluation of groundwater quality. The present studies are aimed to asses the groundwater quality for industrial purposes in view of the mega industries coming up in the area in near future. The need for groundwater quality assessment is of considerable importance as the area is deficient in surface water resources and dependency on groundwater exclusively is due to aberration of monsoon or its game of truancy to meet various sectoral needs. Groundwater being most dependable and its significant role as integral input in ushering a new economic order. With a view to understand the amount of dissolved ions and to asses the quality of groundwater and the variations in the concentrations of different ions have been calculated to evaluate suitability of the groundwater for industrial purposes.

3 illus, 1 table, 18 ref

013465   Neeraj Kumar;Tripathi P (Agrometeorology Dep, G.B. Pant Agri. & Tech. Univ, Pantnagar, Uttarakhand, Email: neeraj34012@gmail.com) : Simulation modeling of rice genotypes of yield attributes at different nitrogen levels and different dates of transplanting using CERES 3.5 v for eastern Uttar Pradesh. Mausam 2009, 60(4), 521-4.

Investigation was carried out at Agromcteorological Instructional Farm of Narendra Dcva University of Agriculture & Technology, Kumarganj, Faizabad (U.P.) during Kharif season of 2005-06 to investigate the CERES v 3.5 model validations for rice at different dates of transplanting and different genotypes. Treatment consisted of three genotypes, viz., Sarjoo-52, NDR-359 and Pant Dhan-4, two dates of transplanting, viz., July 5, 2005 and July 25, 2005 & three nitrogen levels, viz., 80 kg/ha, 120 kg/ha and 160 kg/ha. The experiment was laid out in Randomized Block Design (RBD). From the response of simulation model il is observed that accuracy of simulated value decrease with late sowing in all the genotypes. Among the varieties the Pant Dhan-4 was found to have maximum closeness to observed value followed by Sarjoo-52 and NDR-359 at all nitrogen level for Biomass (gm/m²). Grain yield predication at 120 kg N level was found closest in Pant Dhan-4 and Sarjoo-52, while in NDR-359 shows the better closeness at 160 kg N in both dates of transplanting. In the weight/grain (gm) 120 kg nitrogen level was found to have highest accuracy of (100%), i.e., no difference between observed and predicted value in both transplanting dates and nitrogen level.

2 tables, 7 ref

013464   Muthuchami A (NO, Meteorological Centre, Bangalore, Email: mcbangalore@imdmail.gov.in) : Variability in dynamic and thermodynamic parameters in cyclogenesis over north Indian ocean. Mausam 2009, 60(1), 61-72.

The two basins Arabian sea (ARS) and Bay of Bengal (BOB) of the North Indian Ocean (NIO) are having different dynamic and thermodynamic character and therefore ARS has subdued cyclone activity than BOB. In order to examine the difference between these basins in respect of various meteorological parameters, using NCEP/NCAR reanalysis data for the period 1971-2005 during the months of September to December the distribution of the dynamic and thermodynamic parameters are discussed. It is seen that sea surface temperature (SST) is not responsible for subdued activity over ARS as the SST over ARS and BOB is mostly above minimum threshold level. In respect of wind shear, during October in ARS north of 10° N is favourable for storm formation unlike September where the whole of Arabian sea except the region north of 20° N is inert to cyclone formation. The humidity factor is more pronounced in ARS for prohibiting storm formation than shear factor. In all the months static instability at 90° E is least and so the atmosphere is neutral throughout the period and consequence of it any small trigger in the lower level will induce the system to grow further. The BOB is more barotropic than ARS. There is a considerable difference exists in precipitation rate as a consequence of more stable atmosphere over Arabian sea than in Bay of Bengal even at the lower level.

5 illus, 2 tables, 17 ref

013463   Mohapatra M;Naresh Kumar;Bandyopadhyay B K (India Meteorological Dep, , New Delhi-110 003, Email: mohapatra_imd@yahoo.com) : Role of mesoscale low and urbanization on exceptionally heavy rainfall event of 26th july 2005 over Mumbai: some observational evidences. Mausam 2009, 60(3), 317-24.

The 26th July 2005 exceptionally heavy rainfall event over Mumbai has been mainly attributed to a mesoscale low/vortex off Konkan coast and urban heat island (UHI) effect as demonstrated by various research groups. However, these studies are limited on observational evidence regarding the existence of the mesoscale vortex and UHI prior to and during this heavy rainfall event. Hence, a study has been undertaken to examine the existence of the mesoscale low off Konkan coast, which might have triggered this exceptionally heavy rainfall over Mumbai and the possible role of UHI effect over Mumbai on this heavy rainfall event. For this purpose the additional synoptic data from Mumbai high region and daily maximum and minimum temperatures over Mumbai region have been analysed. The analysis confirms the existence of a mesoscale low pressure area and isallobaric low to the west of Dahanu during 25th -26th July 2005. The analysis of daily maximum and minimum temperatures over Mumbai region confirms the UHI effect during 25lh-26'" July, 2005.

4 illus, 15 ref

013462   Mohapatra M;Mohanty U C (NO, India Meteorological Dep, New Delhi, Email: mohapatra_imd@yahoo.com) : Excess and deficient summer monsoon rainfall over Orissa in relation to low pressure systems. Mausam 2009, 60(1), 25-38.

A study has been undertaken to find out different characteristics like frequency, intensity, movement, region of occurrence etc. of low pressure systems (LPS) including low, depression and cyclonic storm etc. developing over Orissa and neighbouring sea and land regions during excess and deficient monsoon rainfall months (June - September) over Orissa. The study is based on data of 20 years (1980-1999). The principal objective of this study is to find out the contribution of LPS to extreme monsoon rainfall activity over Orissa. The number of LPS days rather than frequency of formation of LPS over different regions better explain the excess and deficient rainfall over Orissa. The excess rainfall over Orissa during June is not significantly related with the number of LPS days. Significantly less than normal number of LPS days over northwest (NW) Bay of Bengal and Gangetic West Bengal (GWB) and higher number of LPS days over west central (WC) Bay off north coastal Andhra Pradesh (NCAP) cause deficient rainfall over Orissa during June. While significantly higher than normal number of LPS days over NW Bay and Orissa leads to excess rainfall during July, less than normal number of LPS days over WC Bay off NCAP is associated with excess rainfall during August. The less number of LPS days over Orissa due to less frequent movement of LPS across Orissa from the Bay of Bengal leads to deficient rainfall over Orissa during both July and August. Significantly higher/less than normal number of LPS days over NW Bay leads to excess/deficient rainfall over Orissa during September.

9 illus, 7 tables, 25 ref

013461   Mohapatra M;Hatwar H R;Kalsi S R (NO, India Meteorological Dep, New Delhi, Email: mohapatra_imd@yahoo.com) : Verification of heavy rainfall warning over Bihar and Uttar Pradesh. Mausam 2009, 60(2), 175-84.

India Meteorological Department (IMD) issues heavy rainfall warning for a meteorological subdivision when the expected 24 hours rainfall over any rain gauge station in that sub-division is likely to be 64.5 mm or more. Though these warnings have been provided since long and are also now being issued for smaller spatial scales, very few attempts have been made for quantitative evaluation of these warnings. Hence, a study is undertaken to verify the heavy rainfall warning over the representative meteorological sub-divisions of east Uttar Pradesh (UP), west UP and Bihar during main monsoon months of July and August. For this purpose data of the recent 5 years (2001-2005) and also for another epoch of 5 years in the early 1970s has been taken into consideration. In this connection, the day when heavy rainfall is recorded over atleast two stations in a sub-division, has been considered as a heavy rainfall day for that subdivision. This study of verification shows that probability of detection of heavy rainfall is 64% over Bihar, 52% over east UP and 53% over west UP for the recent 5 years. Compared to early 1970s, there has been slight improvement in the forecast skill during 2001-2005 with probability of detection increasing by about 10-20% and with decrease in missing rate and false alarm rate. However, the false alarm rates are still large indicating higher bias towards over-prediction. The synoptic conditions associated with the heavy rainfall events have been collected for the period 2001-05 and analysed. The analysis of the unanticipated heavy rainfall events suggests that though proper interpretation of synoptic charts and NWP outputs could improve the warnings, the forecast system available even today is still not capable to capture every heavy rain event in advance.

2 illus, 6 tables, 14 ref

013460   Mohapatra M;Hatwar H R;Bandyopadhyay B K; Subrahmanyam V (NO, India Meteorological Dep, New Delhi-110 003, Email: mohapatra_imd@yahoo.com) : Evaluation of heavy rainfall warning over India during summer monsoon season. Mausam 2009, 60(4), 475-90.

India Meteorological Department (IMD) issues heavy rainfall warning for a meteorological subdivision when the expected 24 hours rainfall over any rain gauge station in that sub-division is likely to be 64.5 mm or more. Though these warnings have been provided since the inception of IMD, a few attempts have been made for quantitative evaluation of these warnings. Hence, a study is undertaken to verify the heavy rainfall warnings over 36 meteorological sub-divisions of India during monsoon months (June-September) and season as a whole. For this purpose, data of recent 5 years (2002-2006) has been taken into consideration. In this connection, the day when heavy rainfall is recorded over at least one station in a sub-division, has been considered as a heavy rainfall day for that sub-division. There is a large spatial and temporal variability in skill scores of heavy rainfall warnings over India during summer monsoon season. Considering the monsoon season as a whole, the Heidke Skill Score (HSS) is relatively less (<0.20) over the regions with less frequent heavy rainfall like Lakshadweep, southeast peninsula, Vidarbha, Marathwada, Jammu & Kashmir, Arunachal Pradesh and Nagaland, Manipur, Mizoram & Tripura (NMMT). It is higher (<62> 0.50) over Konkan & Goa, Madhya Maharashtra and Gujarat region. There has been improvement in the forecast skill with gradual increase in the critical success index and Heidke skill score over the years mainly due to the Numerical Weather Prediction (NWP) models' guidance available to the forecasters. However, the false alarm rate and missing rate are still very high (<62> 0.50), especially over many sub-divisions of northwest India, southeast peninsula and NMMT.

11 illus, 1 table, 18 ref

013459   Mazumdar A B;Khole M;Sunitha Devi S (NO, Meteorological Office, Pune-411 005) : Cyclones and depressions over the north Indian ocean during 2009. Mausam 2010, 61(3), 271-90.

10 illus, 3 tables, ref

013458   Mazumdar A B;Khole M;Sunitha Devi S (NO, Meteorological Office, Pune-411 005) : Cyclones and depressions over the north Indian ocean during 2008. Mausam 2009, 60(3), 267-88.

9 illus, 3 tables

013457   Mazumdar A B (NO, India Meteorological Dep, Pune, Email: abmazumdar@gmail.com) : Precipitation regionalization of southwest monsoon by hierarchical cluster analysis. Mausam 2009, 60(2), 185-96.

An attempt has been made to identify coherent zones of southwest monsoon rainfall over the Indian region by employing hierarchical cluster analysis. Examination of dendrograms produced by different fusion strategies revealed the presence of 13 nuclei clusters of meteorological subdivisions. Formation of these nuclei clusters could be interpreted by their average principal component (PC) scores and associated synoptic features of PCs. Higher level inter-nuclei joinings have occurred in various fusion strategies to produce different types of clusters of subdivisions. A flexible strategy providing well separated groups of meteorological sub-divisions has been found to be suitable. The method has identified six homogeneous regions of rainfall over India. The meteorological subdivisions have been found to be evenly distributed in these coherent zones. The clustering obtained by this method has been reasonable and largely interpretable.

4 illus, 4 tables, 38 ref

013456   Lal R P;Suresh Ram (India Meteorological Dep, , New Delhi, Email: lalrp@yahoo.com) : Climatology of blizzards over Schirmacher Oasis, east Antarctica. Mausam 2009, 60(1), 39-50.

Weather in Antarctica is subject to frequent and sudden changes. Strong winds and blizzards dominate Antarctic weather. A combination of blowing snow, gale force wind and very low visibility is normally defined as blizzard. Meteorological data recorded at Indian Antarctic Station Maitri, in respect of blizzards recorded during the period 1990-2005 has been studied to find out climatological features of blizzards affecting Schirmacher Oasis. At Maitri the blizzard is mostly associated with extra-tropical storms and is normally preceded by precipitation. On average during the year about 21 blizzards affects the station for 45 days during the year. During the month of April to August 3 to 4 blizzards affects the station. Maximum number of blizzards occurs in the month of August with about 7 blizzard days. Average wind speed recorded during the blizzard is about 52 kt but it exceeded 100 kt on several occasions. The duration may vary from hours to days with average of 25 hours. Longest duration of 168 hours was recorded in June 1997. There are about 12 such occasions when blizzard lasted more than 72 hours. No correlation has been found between maximum wind speed and temperature rise during blizzard and the speed is also not correlated with pressure departure during the period.

10 illus, 3 tables, 19 ref

013455   Khole M (NO, India Meteorological Dep, Pune, Email: medhakhole@hotmail.com) : Meterological conditions associated with very sluggish advance of Indian summer monsoon in 2002. Mausam 2009, 60(1), 51-60.

In the year 2002, the monsoon covered entire India on 15th August, one month later than the normal date. An attempt has been done in this study to analyse the meteorological conditions underlying this abnormally sluggish advance of the monsoon in 2002, using the NCEP-NCAR Reanalysis data sets. It has been observed that, there had been an anomalously high influence of systems in the westrelies during the advance phase of Indian Summer Monsoon in 2002. This has proved to be a factor unfavourable for the advance of the monsoon. Similar cases of hiatuses in the advance of monsoon during other recent years of delayed advance, viz., 2004 and 2006. have also been discussed.

5 illus, 2 tables, 11 ref

013454   Kanth T A;Ul Hassan Z (Geography Dep, Kashmir Univ, Srinagar, Jammu and Kashmir, Email: author@tasawoork@yahoo.com) : Assessment of land use/land cover change in wular catchment using remote sensing and GIS. Trans Inst Indian Geogr 2010, 32(1), 53-62.

An improved understanding of land use and cover change is considered to be a requirement for the global assessment of landscape dynamics. It is essential for the development of management strategies and policies to prevent further decline in the environmental value. A watershed is an ideal unit for management of natural resources and mitigation of impacts. The present study is an attempt to determine the spatio-temporal land use/land cover change in Wular Catchment and to find out the major factors causing the change. The Datasets used for present study consist of SOI toposheets, 1961 of 1:50000 scale and IRS 1C LISS III, Oct 2004 imagery with a resolution of 23.5 meters. On screen digitization and supervised classification approaches were used for the assessment of changes in land use/land cover. The results indicate that Dense Forest has drastically decreased by 16.2% of the total Catchment from 1961 to 2004. Agriculture and Built up area have been extended on 5.2% and 3.0% of the total area, while as 3.0% of the land has been rendered barren. Thus erosion and other degradation process induced by human intervention is an imminent threat to the fertility and stability of the mountainous landscape of the study area.

6 illus, 2 tables, 15 ref

013453   Kale C N (Geography Dep, S.G. M. College, Vidyanagar, Karad-415 124) : Causes of floods in Upper Krishna basin of Maharashtra. Nat Envir Pollut Technol 2009, 8(2), 287-95.

Attempts to analyse probable causes of flood situation in upper Krishna basin of southern Maharashtra. Flood situation has become disastrous during the years 2005 and 2006 in later part of July and early August in upper Krishna basin. It is also important to note that floods are aggravated phenomena by human and natural activities. About 27.72% of the geographical area of the upper Krishna basin of southern Maharashtra is affected by floods of which about 2.12% of total population of Upper Krishna basin has suffered in 2006. Since, the floods of rivers are responses of both natural and anthropogenic factors, the relative effects and causes vary from place to place. To analyse the causes of flood situation in the region under study, the statistical data and concerned information have been collected through personal visits and records available at Tehsil headquarters of Sangli, Kolhapur and Satara districts.

3 illus, 4 tables, 6 ref

013452   Jenamani R K;Vashisth R C;Bhan S C (NO, India Meteorological Dep, New Delhi-110 003, Email: rjenamani@hotmail.com ) : Characteristics of thunderstorms and squalls over Indira Gandhi International (IGI) airport, New Delhi-impact on environment especially on summer's day temperatures and use in forecasting. Mausam 2009, 60(4), 461-74.

In the study, commencement timings and duration of thunderstorms (TS) and squalls at IGI airport, Palam, New Delhi have been analysed critically based on most recent eleven years data of 1995-2005 to find their favourable time of occurrences. Then utility of such data base in the aviation warning has been demonstrated. Environmental changes associated with these squalls have also been further analysed to understand their impact. Being recent May 2007 a very cool month over Delhi, the role of TS on controlling the day's soaring temperature has also been studied from their data. Results show TS are maximum in June followed by July whereas squalls are maximum in May followed by June. It shows more than 80% of TS in each season are of duration less than 3 hours with remaining are mostly 3 to 6 hours. The peak time period of commencement of both TS and squalls in the day differ with the progress of the months. For pre monsoon months, the most favourable timing of TS and squalls are 1200-1500 UTC while for monsoon, it starts earlier. Around 37% of the total TS during the period were associated with squalls. The average maximum wind speed in squall at IGI airport is about 68 kmph with highest maximum wind speed 139 kmph. On an average the environmental temperature falls by 5.6° C, humidity levels rises by 17.8% and mean sea level pressure rises by 1.6 hPa due to the occurrences of squalls. Study also shows daily maximum temperature rise is highly controlled by TS occurrences and May 2007, being a month of highest TS occurrences at the airport since 1995, became one of the coolest month in May over Delhi. The comparison of TS frequencies shows 12% increase in their annual activities since 1950-1980 with very high unusual increase of 51% in June and 26% in May. Since analysis of data from 1995 shows occurrences of TS are reversely but strongly correlated with summer temperatures and longer period temperature data.

8 illus, 3 tables, 6 ref

013451   Jaswal A K;Prakasa Rao G S (NO, India Meteorological Dep, Pune-411 005) : Recent trends in meteorologial parameters over Jammu and Kashmir. Mausam 2010, 61(3), 369-82.

Annual trends of meteorological parameters temperature, rainfall, relative humidity and clouds for ten stations in Jammu and Kashmir during the period 1976-2007 were studied. Trend analysis shows that temperatures are increasing over the state with significant increase in maximum temperature in the Kashmir region (+0.04 to + 0.05° C/year) and minimum temperature in the Jammu region (+0.03 to + 0.08° C/year). The diurnal temperature range (DTR) is increasing over Kashmir region due to higher increasing trends in the maximum temperature while the strong increasing trends in the minimum temperature are contributing more towards the decrease in DTR over the Jammu region. Annual rainfall and rainy days trends are decreasing in both the regions of the state except at Jammu where rainfall trend is significantly increasing (+12.05 mm/year). Day-time relative humidity trends are mixed while total cloud amount trends are decreasing over Kashmir region and increasing over Jammu region. The effects of urbanization in the last two decades are more pronounced in Jammu region and this is strongly expressed in minimum temperature over the region. The warming trends observed over Jammu and Kashmir state during the period of study need further investigation in relation to variability of atmospheric circulation over North India.

9 illus, 3 tables, 30 ref

013450   Jaswal A K (NO, India Meteorological Dep, Pune, Email: akjaswal@imdpune.gov.in) : Sunshine duration climatology and trends in association with other climatic factors over India for 1970-2006. Mausam 2009, 60(4), 437-54.

Changes in sunshine duration in association with total cloud amount, rainy days and good visibility days over India were examined for 1970-2006. Climatologically, annual total sunshine duration over west Rajasthan and adjoining Gujarat is more than 3100 hours which is ideal for harnessing solar energy over these regions. The trend analysis indicates significant decrease in sunshine duration over the country for all months (except June) and the maximum decrease has taken place in January (-0.44 hour/decade) followed by December (-0.39 hour/decade). Seasonally, decline in sunshine hours is highest in winter and post monsoon (4% per decade) and lowest in monsoon (3% per decade). Decadal variations indicate maximum decrease in sunshine over the Indo-Gangetic plains and south peninsula during 1990-1999. Spatially, the decreasing trends in sunshine hours are highest in Indo-Gangetic plains and south peninsula while regions over Rajasthan and Gujarat have lowest decrease. Out of 40 stations under study, the maximum decrease in sunshine has occurred at New Delhi (winter at 13% per decade and post monsoon at 10% per decade) and Varanasi (summer and monsoon at 7% per decade). Correlation analysis of sunshine duration with total cloud amount, rainy days and good visibility days indicates regional and seasonal variations in factors explaining the long term trends in sunshine duration over the country.

10 illus, 3 tables, 39 ref

013449   Geetha B;Raj Y E A (NO, Regional Meteorological Centre, Chennai, Email: geethab67@gmail.com) : Role and impact of Siberian high on the temporal variation of Indian northeast monsoon rainfall. Mausam 2009, 60(4), 505-20.

The relation between the intensity of Siberian High, defined as the mean sea level pressure over the Siberian region bounded by 87.5 & 102.5° E longitudes and 47.5 & 52.5° N latitudes (PSH) and Indian northeast monsoon rainfall has been studied in antecedent and concurrent modes based on monthly/seasonal mean PSH and monthly/seasonal rainfall data of Tamil Nadu (NMR) for the 34 year period, 1971 to 2004. It has been found that a positive relationship exists between the PSH and NMR of October-November (ON) which is significant in the antecedent mode [PSH(AS/Sep)] and modest in concurrent mode. The relationship turns negative for NMR (Dec) with both PSH(Sep) (antecedent) and PSH(Dec) (concurrent). By and large, negative anomaly profile of PSH during September-November (SON) followed by a positive PSH (Dec) anomaly is associated with a deficient NMR, but, a normal to positive PSH anomaly profile in SON becoming negative in December is associated with an excess NMR. The manifestation of PSH on NMR has been shown to be by way of modulating the strength of low level easterlies over the Bay of Bengal off the southeast coast of peninsular India as well as the latitudinal positions of Sub Tropical Ridge at 200 hPa (STR) and Equatorial Trough at 850 hPa (ET) over India. An intense PSH (Sep) is associated with strengthening of easterlies over the Bay of Bengal as well as southward location of STR/ET thereby favouring a good NMR (ON). During December, a weaker than normal PSH (Dec) is associated with northward location of ET from its normal latitudinal position near the equator which becomes conducive for good NMR(Dec). That a weaker than normal PSH in December is associated with good NMR(Dec) is comprehended from an analysis of time series of PSH. It has been found that the PSH itself undergoes a phase change in December on most occasions, i.e., an intense PSH (Nov) is by and large, followed by a weaker than normal PSH (Dec) and vice versa.

7 illus, 9 tables, 25 ref

013448   Dutta S;De U S;Sunitha Devi (NO, Meterorologial Office, Pune-411 005, Email: duttapne@yahoo.co.in) : Diagnostic study on the energetics aspects of hiatus in the advance of southwest monsoon. Mausam 2009, 60(4), 427-36.

Advance of southwest monsoon, after its onset, often gets stalled for a week or more causing concern to the farmers and other community whose activities are weather dependent. The present study on the energetics aspect of hiatus in the advance of southwest monsoon over India aims at understanding the dynamical reasons for this. Nine cases of hiatus of duration more than 10 days during 1982-2006 have been selected. For each hiatus case, different energy terms, their generation and conversion among different terms have been computed during the hiatus period and also during the pre-hiatus pentad over a limited region between 65° E to 90° E, 5° N to 30° N. These computations are based on NCEP 2.5° x 2.5° re-analysed daily composite data during different hiatus period and during corresponding pre-hiatus pentad. From this study it is found that: (1) In most of the cases there is a reduction in the generation of zonal available potential energy [G(A_Z)] during hiatus period compared to pre-hiatus pentad. (2) Drop in the conversion from zonal available potential energy to zonal kinetic energy [C(A_Z, K_Z)] during hiatus period has been observed in most of the cases. (3) In most of the cases there is a reduction in zonal kinetic energy (K_Z) and in eddy kinetic energy (K_E) during hiatus period compared to pre-hiatus pentad.

1 illus, 2 tables, 19 ref

013447   Durai V R;Roy Bhowmik S K;Mukhopadhyay B (India Meteorological Dep, , New Delhi-110 003, Email: durai.imd@gmail.com) : Evaluation of Indian summer monsoon rainfall features using TRMM and KALPANA-1 satellite derived precipitation and rain gauge observation. Mausam 2010, 61(3), 317-36.

The study provides a concise and synthesized documentation of the current level of skill of the satellite (3B42RT, 3B42V-6, KALPANA-1) products over Indian regions based on the data gathered during the summer monsoon seasons of 2006, 2007 and 2008. The inter-comparison of satellite products with the rain gauge observations suggests that the TRMM 3B42V6 product could distinctly capture characteristic features of the summer monsoon, such as north-south oriented belt of heavy rainfall along the Western Ghats with sharp gradient of rainfall between the west coast heavy rain region and the rain shadow region to the east, pockets of heavy rainfall along the location of monsoon trough, over the east central parts of the country, over north-east India, along the foothills of Himalayas and over the north Bay of Bengal. The KALPANA-1 and 3B42RT products reproduce only the broadest features of mean monsoon seasonal rainfall. The near real-time products 3B42RT and KALPANA-1 underestimate the orographic heavy rainfall along the Western Ghats of India. The precipitation estimates from TRMM 3B42V6 product, when accumulated over the whole season, could reproduce the observed pattern. However, the TRMM 3B42RT and KALPANA-1 estimates are comparatively lower than the observed rainfall over most parts of the country during the season. Inter comparison reveals that the TRMM 3B42V6 product showed better skill in estimating the daily and seasonal mean rainfall over all India and also over four homogeneous regions of India.

13 illus, 3 tables, 24 ref

013446   Das G K;Samui R P;Kore P A;Siddique L A; Biswas H R;Barman B (NO, Regional Meteorological Centre, Kolkata-700 027, Email: ganesh_das06@yahoo.com) : Climatological and synoptic aspect of hailstorm and squall over Guwahati airport during pre-monsoon season. Mausam 2010, 61(3), 383-90.

Premonsoon season in north-east India is known for thunderstorm activity with moderate to heavy rain, gusty wind, squall and sometimes with the occurrences of hail fall. In this paper an attempt has been made to find out the climatological and synoptical aspects of hailstorms as well as squall over Guwahati Airport (26.18° N, 91.75° E) during Premonsoon season, 20 years data from 1987 to 2006 have been analyzed. The frequency of hail and squall during premonsoon season is observed to be 1.35 and 3.65 respectively. The most favourable time of occurrence of hail is during afternoon to late evening and that for the occurrence of squall is during evening to early morning over Guwahati Airport. The significant synoptic situations associated with occurrence of hail are Sea level trough from East Uttar Pradesh/Bihar to North-East India and low level cycir over Bihar and neighbourhood.

4 illus, 4 tables, 17 ref

013445   Chaudhuri S;Biswas M (Atmospheric Sciences Dep, Calcutta Univ, Kolkata, Email: chaudhuri_sutapa@yahoo.com) : Pattern of meteorological parameters during severe thunderstorms-a frequencuy domain analysis. Mausam 2009, 60(1), 1-10.

Thunderstorm is a high frequency cumulus or cloud scale weather phenomenon and is generated due to instabilities created in the meso-scale. The surface parameters play a significant role in the genesis whereas the strength of the upper air pull is required to assess the growth of the thunderstorms. The thunderstorms associated with hail, high wind gust or tornadoes lead to catastrophe over the particular location. The accurate prediction of the occurrence of thunderstorms is thus, becomes a necessity. The purpose of the present paper is to assess the predictability of severe thunderstorms by viewing the pattern of the meteorological parameters during severe thunderstorms using time series analysis in frequency domain. Analysis in frequency domain involves representation of the data series in terms of the contributions made at different time scales. Fourier analysis represents the fluctuations or variations in a time series as having been arisefi from the adding together of a series of sine and cosine functions. The overall time series is regarded to have generated from the combined effects of the collection of sine & cosine waves oscillating at different frequencies. In the present study the thunderstorm days of STORM Pilot Experiment - 2006 are analysed over Kolkata (22°32', 88°20') and validated the findings with past six year synoptic observations. The study reveals that on the thunderstorm days, temperature gradually increases with time and reaches the maximum value of 32° C at 1400 hours (local time). The time of occurrence of thunderstorms as reported by the Regional Meteorological office is between 1550 to 1610 hours (local time). Similarly the other parameters like relative humidity, wind speed, wind direction and solar radiation show a distinctly different pattern on thunderstorm days. The patterns of meteorological parameters might lead to assess the predictability of such thunderstorms.

6 illus, 15 ref

013444   Biswas H R;Chakrabarti D;Kore P A;Das G K (NO, Regional Meteorological Centre, Kolkata, Email: 786hrb@gmail.com ) : Severe hailstorm over Guwahati airport and its vicinity on 2nd april 2006: synoptic and thermodynamic perspectives. Mausam 2010, 61(3), 391-400.

Climatologically thunderstorm activity is quite common features over Guwahati Airport and its vicinity during premonsoon season. But a severe hailstorm with large size of hailstones and long duration is a rare event. Such a hailstorm with hailstone size of about 25mm occurred over Guwahati Airport (26.1°N, 91.6°E) on 2^nd April, 2006 during midnight. In this paper an attempt has been made to investigate prerequisite synoptic and thermodynamic conditions of the atmosphere associated with this hailstorm. Under favourable synoptic and instability condition of thunderstorm occurrence, veering of winds over Guwahati between freezing level and 500 hPa level with vertical wind shear of horizontal winds exceeding 6.2 ms^-1 km^-1 more appears to be conductive for the development of a hailstorm. Stability Indices viz., Showalter, K., Total-Total and Severe Weather Threat (SWEAT) index have shown predictability for this event.

3 illus, 4 tables, 22 ref

013443   Bhardwaj R;Ashok Kumar;Maini P (Mathematics Dep, Guru Gobind Singh Indraprashta Univ, Delhi, Email: rb_22@rediffmail.com) : Evaluation of bias free rainfall forecast and kalman filtered temperature forecasts T-80 model over Indian monsoon region. Mausam 2009, 60(2), 147-66.

A forecasting system for obtaining objective medium range location specific forecast of surface weather elements is evolved at National Centre for Medium Range Weather Forecasting (NCMRWF). The basic information used for this is the output from the general circulation models (GCMs) T-80/T-254 operational at NCMRWF. The most essential component of the system is Direct Model Output (DMO) forecast. This is explained in brief. Direct Model Output (DMO) forecast is obtained from the predicted surface weather elements from the GCM. The two important weather parameters considered in detail are rainfall and temperature. Both the weather parameters have biases. While the bias from the rainfall is reduced by adopting bias removal technique based upon threshold values for rainfall and for removing bias from temperature forecast a two parameter Kalman filter is applied. The techniques used for getting bias free forecast are explained in detail. Finally an evaluation of the forecast skill for the Kalman filtered temperature forecast and bias free rainfall forecast during monsoon 2007 is presented.

6 illus, 12 tables, 5 ref

013442   Balachandran S;Geetha B (NO, Regional Meteorological Centre, Chennai, Email: balaimd@gmail.com) : Signatures of northeast monsoon activity and passage of tropical cyclones in the integrated precipitable water vapour estimated through GPS technique. Mausam 2010, 61(3), 349-60.

Water vapour represents a key variable in the atmospheric processes. The importance of assessing water vapour availability in the atmosphere is indicated by the currently prevalent use of vast number of observing systems, both of in-situ and remote sensing types, designed to measure its distribution accurately over wide ranges of space and time scales. One of the widely used techniques world over is use of ground based GPS receivers for measurement of total precipitable water vapour in the atmosphere over the station. One such system is being operated at Chennai since 2007. An analysis of hourly Integrated Precipitable Water Vapour (IWV) data received from this system during Northeast Monsoon (NEM) season of 2008 shows the signatures of NEM activity and the passage of tropical disturbances like cyclonic storms and depressions in the vicinity of the GPS observation site. The GPS based IWV values are found to agree fairly well with radiosonde based IWV values and a good correlation exists between them. The IWV values obtained from GPS based system are found to be consistent with activity of Northeast monsoon with increase (decrease) of IWV during active (weak) phase of NEM 2008. The general expected trend of increase in IWV with approach of tropical systems in the vicinity of GPS station, reaching maximum during closest approach and again its decrease with increase of distance from the station is noticed. The diurnal variation of GPS based IWV estimates during NEM 2008 does not appear to be significant.

8 illus, 1 table, 14 ref

013441   Arun Kumar;Dash S K;Dhaka S K (Centre for Atmospheric Sciences, IIT Delhi, New Delhi, Email: sv19922003@yahoo.co.in ) : Assessment of scale hazards due to pool fire for a fossil fired power plant in India. Mausam 2009, 60(2), 197-210.

Hazards for a fossil fired power plant located at coastal Gujarat in India have been assessed. The trajectory and spread of the plume from tanks of fossil fired power plant were predicted using existing models named Carter, Mills, Briggs and Zonato during winter and summer seasons with low and high wind speeds observed in day and night hours. Results show that wide areas of habitation and human settlement to the northeast of the site may be potentially under hazards due to southwesterly and southerly winds during summer. Plume heights and widths are found high in the morning hours or late night when wind speeds are low. As wind speed increases around noon, low plume heights and widths are obtained. Length scales become low at low wind speeds and vice-versa. Lethal doses of thermal radiation beyond radial distance of 70 m are within the tolerable limit under hazardous condition.

6 illus, 4 tables, 17 ref

013440   Ansari M I;Sai Krishnan K C (NO, India Meteorological Dep, New Delhi-110 003, Email: mdimaran_ansari@yahoo.com) : Designing of a quadrature oscillator. Mausam 2009, 60(3), 349-52.

This paper is an attempt to design and develop an electronic circuit for Quadrature Oscillator, by using locally available components, to be used in servicing of display units for maintenance of a network of 14 Nos. of SAMEER R/Ts in IMD's upper air network of 39 radiosonde radiowind observation system.

2 illus, 1 table, 3 ref

013439   Akter N;Islam M N (Physics Dep, Bangladesh Engineering & Technology Univ, Dhaka-1000, Email: mnislam@phy.buet.ac.bd) : Employment of MM5 in simulating MCSs developed in and around Bangladesh. Mausam 2009, 60(2), 137-46.

The Mesoscale Convective Systems (MCSs) produce numerous weather hazards with their variety of forms. The formation mechanism of MCSs is thus important to know for Bangladesh and its surroundings, because this region is one of the heaviest rainfall areas in the tropical zone. The meteorologists are studying and analyzing the formation mechanism of different types of MCSs using radar and satellite observations data. Observations are limited to real time, but for planning purposes projected parameters over a certain period obtained from a mesoscale model is the requirement. Consequently, the motivation of this paper is to obtain the evolution and life cycle of MCSs developed in and around Bangladesh during pre-monsoon period through the simulation by a mesoscale model named MM5. In this work the calibration of MM5 model for different cumulus parameterization has been performed during the pre-monsoon period of this region. In the present study two domains with mesh resolutions 45 km x 45 km and 15 km x 15 km are prepared. MM5 runs using different cumulus parameterizations are carried out for sensitivity test. The precipitation simulated by the model are compared structurally and numerically with that of Tropical Rainfall Measuring Mission (TRMM) data products, available data from radar scan and observed rain-gauges rainfall in Bangladesh. Important features like lifetime, maintenance mechanism, traversed path, propagation speed and direction of MCSs developed during pre-monsoon period of 2002 in and around Bangladesh have been pointed out.

9 illus, 12 ref

013438   Abdullah-Al-Mokim M;Debsarma S K;Shafee S (Physics Dep, Dhaka Univ, Dhaka-1000, Email: physics@univdhaka.edu) : Simulation of storm surge associated with cyclones land falling Bangladesh coast. Mausam 2009, 60(3), 289-94.

Describes the basic features of storm surge phenomena using Indian Institute of Technology (IIT) model (installed at Bangladesh Meteorological Department) for the Bay of Bengal. To capture the storm surge scenarios, after the entrance of the cyclone into the northern part of the Bay of Bengal, high resolution IIT model has been used. The analysis area is from 18° N to 23° N and 83.5° E to 94.5° E. Bathymetric data required for the model has been taken from Royal Admiralty Table and ETOPO2 dataset. In this paper, various scenarios of storm surges are developed and then investigated for varying input parameter values. This paper also examines the time-series of surges at the fixed landfall point by using the data of three severe cyclonic storms when the cyclone approaches the landfall point.

4 illus, 21 ref