021582   Pattanaik D R (India Meteorological Department, , Pune) : Pre-monsoon signals and prospect of seasonal forecasting of Indian summer monsoon. Proc TROPMET Natl Symp 2001, (NULL), 143-9.

Many studies in the past have reported composite upper tropospheric cold cyclonic (warm anticyclonic) anomalies over northwest India and neighbourhood prior to deficient (excess) monsoon rainfall years over India. The prospect of using these pre-monsoon signals for the seasonal prediction of Indian summer monsoon is investigated in the study by using 41 years of (1958 to 1998) data obtained from National Centre for Environmental Prediction (NCEP) reanalysis. The Pre-Monsoon Index (PMI) used here is the product of temperature and geopotential height averaged over the region 50°E-80°E, 15°N-35°N at 200 hPa level in the month of May. The PMI with subsequent All Indian Summer Monsoon rainfall (AISMR) shows significant correlation (at 99.9% level) with a Correlation Coefficient (CC) of 0.63. The contingency table between PMI and AISMR does not indicate out of phase relationship with excess AISSMR associated with weak PMI or vice versa. 11 year sliding correlation shows significant CC (<62> 0.6) between AISMR and PMI during the recent decades. Prospect of using this index as a predictor for the AISMR is discussed.

5 illus, 7 ref

021581   Patro B C (Department of Earth Sciences, Sambalpur University, ) : Determination of number frequency of sieve residues. Indian J Earth Sci 2000, 27(1-4), 40-7.

The size range of particles in a sieve residue obtained by sieving a clastic sediment geometrical grade Scale with 4/2 interval can be defined in terms of a Practical Sieving Diameter (PSD) analogous to Wadell's Practical Sedimentation Radius (PSR) of settlng particles. The coefficient 1.25 deduced theoretically by Eadell to account for the excess volume of an irregularly shaped particle over that of a sphere having the same composition and terminal settling velocity as the irregular particles, is empirically found to hold good in estimating PSD which for a sieve with aparture edge length d, thus equals 1.25 d. The Practical Sieve Grain Weight (PSGW) for a sieve residue estimated by deeming PSD as the nominal diameter can be employed as the divisor and the weight frequency (W_f) of the sieve residue as the dividend to obtain the corresponding number frequency (N_f). The Chi square, x², criterio shows that the N_f so obtained is statistically not different from number frequency determined by actual counting and vochsafes the versatility of the aforesaid method to convert W_f to N_f in sieve analysis for coarser-grained sediments.

2 tables, 15 ref

021580   Patil M N;Murthy B S;Parasnis S S (NO, Indian Institute of Tropical Meteorology, Pashan, Pune-411 008) : On the characteristics of turbulent eddies over the moist convective region of the monsoon trough. Proc TROPMET Natl Symp 2001, (NULL), 315-22.

During the Monsoon Trough Boundary Layer Experiment (MONTBLEX) in 1990, the measurements of wind components (u, v and w) and temperature (T) were made using fast response sensor, the sonic anemometer (8.33 HZ) for a selected period at Kharagpur, a representative station of the moist convective zone of the monsoon trough. Using these observations, characteristics of turbulent eddies have been studied. The analysis showes that the spectra of vertical wind and temperature obeyed the Monin-Obukhov scaling. The spectral curve showed a slope of -2/3 in high frequency portion which indicated the existence of inertial subrange. The diurnal variation in the eddy sizes were brought out. Temporal evolution of the eddy diffusivities of momentum and heat were also examined.

2 illus, 10 ref

021579   Panneerselvam C;Jeeva K;Nair K U;Selvaraj C; Gurubaran S;Rajaram R;Rajaram G (Equatorial Geophysical Research Laboratory, Indian Institute of Geomagnetism, Krishnapuram, Tirunelveli-627 011) : First results from the measurements of atmospheric Maxwell currents at an Indian Station, Maitri, Antarctica. Proc TROPMET Natl Symp 2001, (NULL), 365-8.

An instrument to measure the atmospheric air-Earth current, the fundamental parameter of the global electric circuit was commissioned at an Indian station, Maitri, Antarctica in December 1999. The horizontal long wire antenna is used as a sensor for picking up charges that constitute various currents collectively called the Maxwell current. The objective is to understand the response of the experimental setup to various atmospheric electrical and meteorological conditions and to explore the possibilities of detecting the global DC component believed to be the result of global thunderstorm activity. During the fairweather conditions the diurnal variation closely follows the trend of the Carnegie curve.

1 illus, 9 ref

021578   Onkari Prasad (India Meteorological Department, , Mausam Bawan, Lodi Road, New Delhi-110 003) : Subdivision-wise long range forecast of Bi-monthly rainfall during southwest monsoon season. Proc TROPMET Natl Symp 2001, (NULL), 252-7.

3 tables, 6 ref

021577   Nair S;Srinivasan G (Regional Meteorological Centre, , Mumbai) : Spatial coherence of daily rainfall over Maharashtra. Proc TROPMET Natl Symp 2001, (NULL), 537-44.

Examines the spatial organization of daily rainfall during the southwest monsoon season (June - September) over Maharashtra (excluding Vidharba) for the period 1996-2000. Data from about 189 raingauge stations, reported under the Daily Rainfall Monitoring Scheme (DRMS), were quality checked and 78 stations chosen based on 85% availability criteria. Totally dry days have been excluded from the analysis. The resultant data set was initially subjected to the S-mode Factor analysis and later rotated to the varimax criterion. Based on the factor loading co-efficients obtained by the rotation, delineation of daily rainfall regions showing spatial coherence has been attempted. From the analysis four distinct regions (or clusters) emerged, with stations in each cluster occurring in geographically contiguous areas without any input of geographical information. The solutions obtained emphasize the dominant role exerted by the topography of the region on the spatial organization of daily rainfall through its interaction with rain bearing airflows. Results also indicate non-conformity of some locations in the existing meteorological subdivisions. An exhaustive analysis based on a longer time-series of data will be undertaken in the future.

5 illus, 1 table, 9 ref

021576   Mukhopadhyay R K;De U S (Meteorological Office, , Pune-411 005) : Middle atmospheric circulation over India during ENSO and Anti-ENSO years. Proc TROPMET Natl Symp 2001, (NULL), 201-5.

A close association between Indian Summer Monsoon (ISM) rainfall and the Southern Oscillation (SO) is well known. The macro processes in the atmosphere are better expressed in the stratosphere and mesophere than in troposphere. The middle atmospheric oscillation pattern associated with ENSO and Anti-ENSO events has been presented. Rocket Sonde data of Thumba (8030'N, 76054'E) from 1970 to 1993 and Balasore (21°31'N, 86°56'E) from 1979 to 1995 have been used for examining the circulation pattern for the contrasting epochs for an equatorial and tropical India. It has been observed that during ENSO years, the whole middle atmosphere is dominated by westerly anomalies, while easterly anomalies are predominant during the Anti-ENSO years.

2 illus, 1 table, 7 ref

021575   Mukhopadhyay P;Sanjay J;Cheng W;Singh S S; Cotton W R (Indian Institute of Tropical Meteorology, , Pune-411 008) : Simulation of mesoscale feature in the large scale environment associated with a may severe cyclonic storm using RAMS over Indian region. Proc TROPMET Natl Symp 2001, (NULL), 263-9.

A latest version (4.29) of Regional Atmospheric Modelling System (RAMS) developed by the scientists of Colorado State University is being used to study the capability of the model to simulate the prevalent mesoscale features of the large scale environment perturbed by a Severe Cyclonic Storm. The six hourly GAME (Gewex Asian Monsoon Experiment) analyses over ten standard pressure levels and the six hourly radiosonde (RS/RW) data over nine available Indian stations are blended to create the initial and six hourly lateral boundary condition for the model. Ten model is seen to simulate the large scale features associated with the Cyclone and a low level cyclonic circulation over land as an embedded system to the large scale ambient flow. The predicted 24 hour accumulated rainfall in association with the embedded circulation and the cylonic Storm are in qualitative agreement with the observation.

4 illus, 4 ref

021574   Mukherjee B K;Sachan H K (NO, Wadia Institute of Himalayan Geology, 33, GMS Road, Dehra Dun-248 001) : Discovery of coesite from Indian Himalaya: a record of ultra-high pressure metamorphism in Indian continental crust. Curr Sci 2001, 81(10), 1358-61.

Coesite inclusions have been identiied from eclogite in the Tso-Morari crystalline complex of Ladakh (India) by petrography and Raman spectroscopy. This is the first location from where coesite has been identified as inclusion in garnet in the Himalayan belt. The occurrence of coesite supports ultra-high pressure metamorphic event in the Indus Suture Zone. Coesite occurs as inclusions in garnet in which radial cracks are developed, whereas quartz pseudomorph after coesite occurs in the close association with garnet and omphacite. The preliminary P-T estimate revealed coesite formed at the minimum pressure of 28 kbars at 700-800°C. The preservation of metastable coesite in eclogite is strongly regulated by P-T-t path during its uplift and retrograde metamorphism. This finding also indicates that the Indian plate subducted at a steeper angle of palaeosubduction plane from Pakistan to the Ladakh region of India.

2 illus, 26 ref

021573   Mujumdar M;Vaidya V;Krishnan R;Satyan V; Sheshgiri A R (Climate and Global Modelling Division and Computer and Data Division, Indian Institute of Tropical Meteorology, Pune-411 008) : Assessment of experimental ensemble seasonal simulation of the Indian summer monsoon (1997-2000) using COLA GCM. Proc TROPMET Natl Symp 2001, (NULL), 275-81.

Examines the COLA T30L18 GCM simulations of the summer monsoon anomalies during 1997-2000 and compated with observations. Two sets of GCM experiments are presented in which the GCM is integrated using the observed SST forcing. In the second set, the global SST anomalies of May are superposed on the monthly June-September climatological SSTs and persisted during the course of the GCM integration. Both the hindcast and May SST persistence experiments are initiated using the observed initial conditions corresponding to the last week of May. The hindcast experiments show reasonable skill in simulating the monsoon rainfall and circulation features during 1997-2000. On the other hand, the May SST persistence experiments indicate that the behavior of the summer monsoon anolalies depend on the manner in which the SST anomalies evolve spatially and temporally during the monsoon season. It is seen that the simulated monsoon rainfall is rather sensitive to small differences between the SST anomalies of May and those during the monsoon months. Based on the results of the study it is suggested that accurate SST information during the summer monsoon season is necessary for improving the seasonal forecasting of the Indian summer monsoon.

3 illus, 2 ref

021572   Mohapatra M;Dastidar S K;Gupta D C (Meteorological Centre, , Bhubaneswar) : Some aspects of recent heat waves over Orissa. Proc TROPMET Natl Symp 2001, (NULL), 189-92.

1 illus, 4 tables, 5 ref

021571   Mohana Rao K;Murthy K S R;Reddy N P C; Subrahmanyam A S;Lakshminarayana S;Rao M M M;Sarma K V L N S; Premkumar M K;Sree A;Bapuji M (NO, National Institute of Oceanography, Regional Centre, 176, Lawsons Bay, Visakhapatnam-530 017) : Submerged beach ridge lineation and associated sedentary fauna in the innershelf of Gopalpur coast, Orissa, Bay of Bengal. Curr Sci 2001, 81(7), 828-33.

Detailed echosounding and side-scan sonar surveys coupled with SCUBA-diving operations in the inne-shelf region of Gopalpur, Orissa coast revealed the existence of a submerged NE-SW trending ridge lineation between the isobaths of 25 and 35 m. Morphology of this ridge indicates parallel to sub-parallel pinnacles with variable relief and widths. Very steep scaps in the leeward side of the seabed at many places are attributed to large-scale seabed scouring. Diving operations recovered extensive live sedentary fauna such as sponges, gorgonians, soft and hard corals along with rock encrustations from the ridge features. X-ray diffraction analysis of the rock samples revealed the mineral composition of quartz, feldspars, and low and high masgnesium calcite, suggesting the morphological features to be of beach sandstone formation. High-resolution shallow seismic records indicate that the features are from the hard subsurface reflector, probably of Late Pleistocene. The composition of sedentary fauna is discussed and its association over the features is attributed to the availability of porous beach sandstone which favours growth in euphotic zone.

5 illus, 20 ref

021570   Marchand M;Bert van der Valk (NO, , ) : Integrated coastal zone management in Andhra Pradesh. Proc TROPMET Natl Symp 2001, (NULL), 545-51.

Within the framework of the Andhra Pradesh Cyclone Hazard Mitigation Project, financed by the Government of AP under a World Bank loan. A study on integrated coastal zone management (ICZM) was performed aiming at long-term mitigation of effects of cyclones. Integrated coastal zone management can be defined as the management of all coastal resources in such a way that net outputs are maximised in the context of certain constraints. WIthin ICZM, hazards are constraints. ICZM defines the objectives for hazard mitigation and provides a framework that determines hazard protection investment levels. Two elements of this framework are described.

1 illus, 3 tables

021569   Mandke S K;Ramesh K V;Soman M K;Satyan V (Indian Institute of Tropical Meteorology, , Dr Homi Bhabha Road, Pune-411 008) : El nino and Indian summer monsoon of 1997: study with AGCMs. Proc TROPMET Natl Symp 2001, (NULL), 282-6.

Impact of 1997 El Nino on Indian Summer Monsoon simulated by 10 Atmospheric General Circulation Models (AGCMs) in 10 ensemble integrations carried out under CLIVAR/Asian-Australian AGCM Intercomparison Project' have been studied. Ensemble mean precipitation anomaly and Southern Oscillation indices for summer 1997 in 10 AGCMS are compared with observations. Observed seasonal mean precipitation over India in summer 1997 was normal (102%) in spite of strong El Nino. Most of the models simulated correct sign of precipitation anomaly over India when compared with observed though magnitude differs. Spatial distribution of precipitation anomaly over 10°S - 40°N, 30°E-120°E region for summer 1997 simulated by 10 AGCMs is compared with observations. Strong negative anomaly over equatorial East Indian Ocean is noticed in observation, which is well simulated by all models except IAP and GFDL. All AGCMs showed skill in simulating Southern Oscillation Index.

2 illus, 1 table, 7 ref

021568   Mallan G V;Krishnakumar G (Regional Meteorological Centre, , Colaba, Mumbai-400 005) : Patterns of Wind shears in Tropical easterly jet (TEJ) and monsoon variability in the recent decade. Proc TROPMET Natl Symp 2001, (NULL), 222-7.

Tropical Easterly Jet (TEJ) is one of the most important components of the Monsoon Circulations. Using the upper air-data of 17 Indian stations and two foreign stations (viz., Kota Baharu and Singapore), for the period of recent decade (1987 to 1996) during the monsoon months (June to September), an attempt is made to analyse the patterns of wind shears, maximum wind and anomalous shears of TEJ and to examine the behaviour and structure of TEJ with intensity, variation and aerial distribution of Indian Southwest Monsoon Sub-divisional rainfall, Frequency and intensity of synoptic systems are also studied. The influence of TEJ on the development and intensification of monsoon depression is discussed.

2 illus, 2 tables, 4 ref

021567   Mallan G V (Regional Meteorological Centre, , Colaba, Mumbai-400 005) : On the weakening of the cyclonic storm over Bay of Bengal on 31st March 2000. Proc TROPMET Natl Symp 2001, (NULL), 53-9.

Formation and dissipation of cyclonic storms over Bay of Bengal in the month of March is a rare atmospheric phenomena. It is more unusual when a storm forms and moves towards North and rapidly weakens. A low pressure area was formed over the South East Bay and adjoining Andaman sea on 27th March 2000 and concentrated into depression on 29th March centered at within half a degree Lat. 120N and Long.87.50E. This system further intensified into deep depression on 29th evening and cyclonic storm on 30th March. It remained practically stationary on 31st and weakened rapidly into a depression and low pressure on the same day. The reasons for the weakening of this fully developed cyclonic storm were investigated. It is inferred that the Ocean water circulation or upwelling affected the intensity of the storm. There is a clear evidence of this system over cold ocean waters which was existing over East Central Bay. Upper level circulation features were also studied during the weakening of the cyclonic storm. The air-sea interactions associated with upper air circulation characteristics for the weakening of the cyclonic storm were discussed.

6 illus, 1 table, 8 ref

021566   Mali R R;Balwalli R R;Basarkar S S;Dikshit S K (India Meteorological Department, , Shivaji Nagar, Pune-411 005) : Time variations of RVR within the approach control area of airport in India. Proc TROPMET Natl Symp 2001, (NULL), 496-504.

With the advent of modern high speed and super sonic aircrafts and the progressively stringent requirement of meteorological parameters, such as visibility, RVR etc. for their landing/takeoff operation, a provision of accurate and continuously updated parameters to the pilot has assumed great importance. Transmissometers [to monitor MOR (visibility) and RVR] are installed for continuously monitoring these parameters at the airports. These instruments support ILS CAT-II type requirements for air navigation at major airport in India. Because of ever increasing aviation activity, there is growing demand for CAT-III type of operational instruments, to be installed at major national and International airports in India. Attempt has been made to provide information on short-term variability of RVR, obtained with the help of instruments installed near touch down point, for two International airports, Viz. New Delhi and Chennai, by analysing the data for the year's 1991-94, at these airports.

8 illus, 2 tables

021565   Mahapatra S;Singh S S (NO, Indian Institute of Tropical Meteorology, Pune-411 008, ) : Simulation of a thunderstorm event by ARPS mesoscale model. Proc TROPMET Natl Symp 2001, (NULL), 289-93.

A high resolution nonhydrostatic mesoscale model `ARPS' was used for simulation of a thunder storm event which occurred at Agartala station in the early morning of 2 May, 1979. The model was integrated for 3 hours using input of Agartala sounding of 0000 hrs UTC on 2 May, 1979 and a selected potential temperature perturbation field. The model domain contained 33 x 33 grids in the horizontal with a model resolution of 2 km and 33 vertical levels at an interval of 0.5 km. Time evolution of maximum vertical velocity (Wmax) group showed Wmax reaching high values, representing strong convention. 3 hours model run produced considerably high rainfall over the station using Kessler warm rain microphysics option.

2 illus, 5 ref

021564   Kushwaha H S;Rai H K;Rathore L S (Department of Soil Science, College of Agriculture, G B Pant University of Agriculture and Technol, Pantnagar) : Verification of medium range weather forecast for Tarai and Bhabar agroclimatic zone of Uttar Pradesh. Proc TROPMET Natl Symp 2001, (NULL), 466-71.

Verification of medium range weather forecast generated at National Centre for Medium Range Weather Forecasting (NCMRWF), Mausam Bhawan Complex, New Delhi using numerical weather prediction (NWP) model, for Tarai and Bhabar agroclimatic zone of Uttar Pradesh was carried out for 8 years from 1992-93 to 1999-2000 with the actual meterorological parameters recorded/experienced at meteorological observatory situated at Pantnagar (U.P.). The forecast parameters included cloud cover, rainfall, wind speed and direction and change in maximum and minimum temperatures. The technique of weather forecast generation involved production of NWP products based on global data assimilation and forecasting, comprising data processing and quality control, data assimilation involving spectral statistical interpolation scheme and an intermittant assimilation cycle based on short range global forecasts, global spectral model with triangular truncation of 80 waves in the horizontal and 18 layer in the verticalm post processing and diagnostics etc. generating forecast for 120 hours based on OOUTC initial conditions. The verification of NWP product for above weather parameters showed that there were improvements in the medium range weather forecast for most of the variables generated at NCMRWF from 1992 to 1998. However, there is a need for further improvement in the rainfall during the months of July, August and September; and in minimum temperature durign January, February, November and December

2 illus, 1 table, 4 ref

021563   Kulkarni M A;Khade V M;Sivaramakrishanan S; Rama G V;Sen P N (Department of Space Sciences, University of Pune, Pune) : Wind profiles in the surface boundary layer over Shar. Proc TROPMET Natl Symp 2001, (NULL), 347-52.

Wind profiles have been constructed using observations recorded at the 7 levels (10m, 20m, 30m, 40m, 60m, 100m) of the 100m tower at SHAR for 1994-1998. An attempt has been made to find theoretical profiles. It has been found that Power Law is better fit than the Logarithmic Law at all hours of the day in all the months.

3 tables, 3 ref

021562   Kulkarni J R;Vinaykumar;Mujumdar M;Satyan V (Indian Institute of Tropical Meteorology, , Dr. Homi Bhabha Road, Pune-411 008) : Simulation of wind stresses by AGCMS for driving an ocean model. Proc TROPMET Natl Symp 2001, (NULL), 270-4.

The monthly surface wind stresses simulated by COLA AGCM over Indian Oceanic region, for the period 1982-1994, are compared with monthly NCEP wind stresses. The wind stresses are decomposed into zonal and meridional components. The distribution of correlation coefficients (CCs) of monthly zonal wind stresses between COLA and NCEP shows regions of high and significant CCs over west Arabian Sea. Bay of Bengal, and southwest Indian Ocean. Low and insignificant CCs are observed over southeast Indian Ocean. Similar distributions of CCs for meridional wind stresses have been observed. The annual cycle of the area-mean wind stresses shows good agreement over Arabian Sea, overestimation over Bay of Bengal, southern Indian Ocean, and understimation over west-equatorial Indian Ocean. The spatial distribution of percentage errors in the wind stress simulations for monsoon season shows that the errors, in general are of the order of 30-40% over most of the region, the maximum reaching to 60% over East Arabian Sea near the Indian coast for meridional components. It is shown that the errors are reduced significantly after removing the systematic bias by subtracting the difference between the monthly means of Cola and NCEP at each of the grid points from the COLA stresses.

2 illus, 3 ref

021561   Kulkarni B D (Indian Institute of Tropical Meteorology, , Pashan Pune-8) : Relationship between centre of the rainstorm and its areal extent - a case study for the Godavari river basin. Proc TROPMET Natl Symp 2001, (NULL), 531-6.

An attempt has been made to find a suitable relationship between central rainfall and the average maximum raindepths over different areas around a rainstorm of severestorm of severemost rainstorms of the plain areas of Godavari river basin using exponential equation of the form: y=100E^-ran

2 illus, 2 tables, 5 ref

021560   Kulkarni A V;Mathur P;Rathore B P;Alex S; Thakur N;Manoj Kumar (Space Applications Centre, Indian Space Research Organization, Ahmedabad-380 015) : Effect of global warming on snow ablation pattern in the Himalaya. Curr Sci 2002, 83(2), 120-3.

^ssc8 illus, 7 ref

021559   Krishna Rao A V R;Valk B V D;Ramana Murty M V;Ramana Murty P V (Delft Hydraulics, , Meridian Plaza, 4th Floor, Ameerpet, 500 016 Hyderabad) : Community response to cyclone warnings. Proc TROPMET Natl Symp 2001, (NULL), 39-44.

4 illus, 4 ref

021558   Krishna Murty L;Loe B R (India Meteorological Department, , Lodi Road, New Delhi) : Effect of El-Nino and Non El-nino events over Indian summer monsoon rainfall. Proc TROPMET Natl Symp 2001, (NULL), 236-43.

The Summer Southwest Monsoon (June-Sept.) is a main rain bringing season for the whole of India. The country as a whole gets about 80% of its annual normal rainfall during this season. In the study, no one-one correspondence has been found between the Indian Summer Monsoon Rainfall (ISMR) and El-nino during the last century (1901-2000). This fact has been further supported by insignificant correlation coefficient (-0.249) between the ISMR and equatorial Sea Surface Temperature (SST) values (of Nino 2 region) averaged from June to September during the period 1951-2000.

2 illus, 2 tables, 6 ref

021557   Kolvankar V G (Bhabha Atomic Research Centre, Seismology Division, A & CMP Group, Trombay, Mumbai-400 085) : Method of commissioning a radio telemetered seismic network at any location. Proc TROPMET Natl Symp 2001, (NULL), 88-97.

Study of seismicity of any earthquake prone area is undertaken to find the cause of the event and also to deduce any possible future hazards. This is normally done by establishing a seismic network and gathering data for the micro-earthquakes taking place. Based on experience of design, development and commissioning of a radio telemetered seismic network (RTSN) at Bhatsa, Thane Distr., Maharashtra state, to monitor reservoir induced seismicity of this region and the up-gradation of this network in recent time, a proposal is being made to commission this type of network at any desired place (barring some rough terrain like in Himalayan region) within the shortest possible time. The usefulness of this network over the conventional network [of operating number of micro-earthquake recorders] is illustrated. This report also highlights the instrumentation of RTSN and provide step by step procedure for commissioning this network. Estimates of cost sturcture and manpower requirements are also provided.

2 illus, 12 ref

021556   Khadge N H (National Institute of Oceanography, , Dona Paula, Goa-403 004) : Geotechnical properties of siliceous sediments from the Central Indian Basin. Curr Sci 2002, 82(3), 338-43.

Indian Deep-Sea Environment Experiment (INDEX) was carried out in a pre-selected area with low nodule abundance and uniform sediment type, for the purpose of environmental impact assessment of future deep-sea mining activities. Geotechnical testing of sediments was part of this multidisciplinary programme and was carried out on siliceous sediments from the Central Indian Basin. Sediments showed change in undrained shear strength and natural water content due to a simulated disturbance experiment conducted in the area. An increase in water content and significant decrease in the shear strength was observed in sediment layer of 0-5 cm from the disturbance area, but no significant changes were noted outside the area of disturbance. High values of porosity and water content were due to presence of 10-20% radiolarian tests and water-absorbing montmorillonite. The prominent loss of undrained shear strength of the sediments exposed to physical disturbance would affect the bearing capacity of the sediment and thus restrict the movement of the nodule collector. Other index properties such as wet bulk density, porosity and specific gravity inside and outside the disturbed zone remained unchanged, mainly due to similar grain size and dominant clay mineralogy.

4 illus, 3 tables, 28 ref

021555   Khade V M;Kulkarni M A;Kulkarni J R; Sivaramakrishnan S;Rama G V;Sen P N (Department of Space Sciences, University of Pune, Pune) : Temporal variability of zonal and meridional winds in the surface boundary layer over Shar. Proc TROPMET Natl Symp 2001, (NULL), 353-6.

The Variability of the Zonal (u) and Meridional (v) components of wind at each of the 7 levels (10m, 20m, 30m, 40m, 60m, 80m, 100m) of the 100m tower at SHAR has been studied. The variance has been found to be large, particularly for the meridional component. The time series analysis of the hourly u and v data exhibits periodicity at the synoptic scale, mesoscale and microscale and microscale. The data were further subjected to Fast Fourier Transform (FFT). The FFT analysis shows oscillations of various frequencies both high and low; among them the Madden-Jullian oscillations, diurnal oscillations and semi-diurnal oscillations are prominent.

6 illus, 3 ref

021554   Kalsi S R;Roy Bhowmik S K;Gupta D C;Nath S M (India Meteorological Department, , New Delhi) : Development of super cyclone of Orissa and it s impacts. Proc TROPMET Natl Symp 2001, (NULL), 60-7.

Orissa was battered by a super Cyclonic Storm on 29 October 1999 that made landfall near Paradip. The estimated maximum wind speed reached-260-270 kmph in the core area which produced a huge storm surge that led to sea-level elevation of more than 20 feet and took away valuable lives of nearly 10,000 people. It was accompanied with exceptionally heavy rains which led to devastating floods and cut off the State from the rest of the country. An attempt is made to described the various features of development and movement of this cyclone throught radar and satellite imageries, conventional data and numerical models. The Quasi-Lagrangian Model (QLM) implemented at India Meteorological Department, (IMD) New Delhi in the recent past has been seen to provide realistic numerical guidance for the movement of this cyclone. Development of storm surge in this super cyclone is seen through different models developed in IMD and IIT Delhi.

4 illus, 11 ref

021553   Joseph P V;Rajan C K;Sooraj K P (Centre for Monsoon Studies, Department of Atmospheric Science, Cochin University of Science and Technology, Fine Arts Avenue, Cochin-62016) : Atmospheric conditions during and prior to monsoon onset over Kerala. Proc TROPMET Natl Symp 2001, (NULL), 174-83.

A study is made of the slow evolution of the atmospheric conditions over South Asia and the Indian Ocean for a period of 40-50 days prior to Monsoon Onset over Kerala. This aim is understand the monsoon onset process better to be able to define Monsoon Onset over Kerala unambiguously. Monsoon Onset over Kerala is accompanied by a strong cross-equatorial lower tropospheric monsoon current with an embedded Low-Jet-steam having maximum winds at 850 hPa and by an east-west cloud band passing through Kerala of intense cumulonimbus convection and associated rainfall. About 6 to 8 pentads prior to the onset a similar cloud band passes through Kerala with associated strong lower tropospheric winds. This has been called the Pre-Monsoon Rain Peak. Particularly in years of late onset, the Pre Monsoon Rain Peak occurs in early May and it has been very difficult to distinguish it from the Monsoon Onset over Kerala. The atmospheric evolution leading to Monsoon Onset over Kerala is studied in the zonal winds of 850 hPa and 500 hPA, meridional wind of 850 hPa, sea-level pressure gradient over South Asia, particularly the Arabian Sea and the Outgoing Longwave Radiation field. 850 hPa meridional wind around the equator close to the East African coast and the sea level pressure gradient over the Arabian Sea between the equator and 20°N latitude are found to be signals uniquely related to the Monsoon Onset over Kerala.

4 illus, 11 ref

021552   Jena G K;Pragya;Chittibabu P;Sinha P C;Dube S K;Rao A D (Centre for Atmospheric Sciences, Indian Institue of Technology, New Delhi-110 016) : Tidal circulation in the gulf of Kachchh: a numerical study. Proc TROPMET Natl Symp 2001, (NULL), 301-7.

A two dimensional numerical model is developed for tidal flow in the guld of Kachchh, west coast of India. The model is fully non-linear and uses a semi-explicit finite difference scheme to solve the basic hydrodynamic equations on a staggered grid. The model neglects horizontal diffusion and wind stress terms in the momentum equations and is applied to the gulf region. The model is barotropic, based on shallow water equations to simulate the sea level and circulation in the region. The flow in the gulf is strong with a tidal range of more than 4m. The tides in gulf is mainly represented in the model by the semi-diurnal M2 constituent. The spatial resolution of the model is 750m x 750m. The steady state is reached after 4th tideal cycle and the results of the 5th tidal cycle are analysed. Numerical experiments are conducted to study the water level and circulation in the gulf. The model predicted results compare well with the observed elevation in the gulf. The model also computes the currents at two locations. While computed value at Sikka is reasonable, the one at Salaya is under estimated.

5 illus, 6 ref

021551   Jayaprasad P;Narender B;Arya A S;Ajai (Forestry, Land Use and Photogrammetry Group, Space Applications Centr, Indian Space Research Organization, SAC P O Ahmedabad-380 015) : Extraction of terrain parameters from IRS-1C PAN stereo data using photogrammetric techniques. Curr Sci 2002, 82(3), 333-7.

Digital Elevation Model (DEM) is used for extraction of terrain parameters such as elevation, slope, aspect, contour, drainage pattern, etc. These parameters are often required in preparation of development and conservation plan for natural resources, infrastructure development, town planning, etc. Indian Remote Sensing Satellites IRS-1C/1D carry on-board push broom Linear CCD PAN camera, providing high resolution (5.8 m) stereo imagery of the earth's surface. DEM has been derived from PAN stereo pair of IRS-1C/1D using suitable mathematical models. It has been used to generate contours and extract drainage patterns. DEM generated from stereo data has been validated using ground control points (GCPs) and also by the surface-to-surface comparison method. Evaluation of drainage pattern is carried out by morphometric analysis.

021550   Jamima P;Venkatesan R;Aswatha Narayana P A (Department of Applied Mechanics, IIT Madras, Chennai) : An examination of the surface energy budget for various soil conditions and comparison with field data. Proc TROPMET Natl Symp 2001, (NULL), 357-64.

Conversion of solar energy into thermo dynamical energy of the atmosphere takes place over the surface of the earth. A study of the effects of various soil types on the surface energy budget is vital to understand their influence on atmospheric dynamics. A one-dimensional planetary boundary layer model is used to study the impacts of different soil types on surface parameters like wind, temperature and fluxes. A standard data set from Global Data Base (GDB), commonly used in climate models is used for comparison of mid latitude conditions and also compared with meteorological field data collected for tropical conditions at Kalpakkam.

8 illus, 1 table, 17 ref

021549   Hosalikar K S (Meteorological Office, C S I Airport, Mumbai-400 099) : A study of post-monsoon convective cloud developments around Mumbai airport. Proc TROPMET Natl Symp 2001, (NULL), 520-5.

As flights through thunderstorms (TS) are concerned, it is clearly advisable to avoid TS whenever meteorological & operational conditions make this possibile, as it can cause hazards to aircraft due to ice accretion, lighting, turbulence and static electricity. Post-monsoon season is a seaons of TS for Mumbai and during late September and October, aviation activity is hampered many times due to frequent developments of TS. These local TS can pose a big threat to aircraft operations. Radar observations indicate that during the early post-monsoon season, TS have a preferred time of occurrence and areas over which they are detected. The development and dissipation of cloud cycle has in general a definite time of interval, from late afternoon to early morning i.e 09 to 00 UTC and some times extending further. With typical TS activity in the late afternoon or evening, the dissipation is associated with rainfall. During this period radar echoes are observed to move from land to sea and get dissipated over land or near coastline. The analysis shows that, maximum TS originate over the lakes in South-East of Mumbai. In the study a comparison is also made between movements of TS radar echoes observed during post-monsoon season, with those observed during monsoon and pre-monsoon season. It is also observed that not all TS reach station.

7 illus, 1 table, 5 ref

021548   Gupta A K;Patil R S;Gupta S K (Centre for Environmental Science and Engineering, Indian Institute of Technology, Mumbari-400 076) : Dispersal capacity of the atmosphere over port and harbor area with respect to air pollution. Proc TROPMET Natl Symp 2001, (NULL), 559-63.

Under the Environmental management plan, a meteorological station was set up at Jawaharlal Nehru Port Area, in Navi Mumbai during 1989. In view to maintain good air quality around Harbor and port area, meteorological data for the period January 1977 to December 1999 have been analysed to determine the mixing heights. The diurnal, seasonal and annual variations in mixing height, ventilation coefficient and air pollution potential index have been also determined. The maximum mixing heights for winter, pre-monsoon, monsoon and post-monsoon seasons were 1906, 2808, 1582 and 2046 m respectively. The maximum ventilation coefficient (10530 m3/s.) was recorded in the month of April, while the lowest value was 4398 m2/s. in the month of July. Lowest value of 3 Air Pollution Potential Index (APPI) has been recorded in the month of December and high value of about 7 APPI during March, April and May. The above study can be used for developing pollution control strategies in the port and harbor region.

2 illus, 2 tables, 6 ref

021547   Grew E S;Rao A T;Raju K K V S;Yates M G (Department of Geological Sciences, University of Maine, 5790 Edward T. Bryand Global Sciences Center, Orono, Maine 04469-5790, USA) : Re-examination of quartz-silimanite-hypersthene-cordierite gneisses from the Vijayanagaram district: does surinamite occur in the Eastern Ghats belt. Curr Sci 2001, 81(10), 1353-8.

Reported a boron- and gallium-bearing variety of the rare beryllosilicate surinamite in quartzofeldspathic gneisses from 7 localities near Vizianagaram, the first report of surinamite in India. These surinamite-bearing gneisses are unusually enriched in beryllium compared to other pelitic gneisses, and few non-pegmatitic silicate minerals simultaneously contain significant amounts of beryllium and boron, so the report of surinamite in the Vizianagaram gneisses is of special geochemical and mineralogical interest. In samples from two of the localites studies by Ramesh Kumar et al. Abundant hypersthene was identified. Petrographic study and electron microprobe analysis of minerals in the original samples show these to contain quartz, K-feldspar, aluminum-rich hypersthene (7.92-10.18 wt% Al₂O₃), garnet (on average Alm_0.58 Prp_0.39 Sps_0.01 Grs_0.01), zinc and chromium-poor hercynite, sillimanite (1.47-1.75 wt% Fe₂O₃), magnetite and ilmenite-hematite intergrowths. Secondary cordierite is poor in alkalis and calcium, whereas biotite is rich in titanium and fluorine. Mineral compositions indicate that these gneisses crystallized under relatively oxidizing and very dry conditions near 1000° and 7 kbar.

2 illus, 5 tables, 23 ref

021546   Ghosh A K (Birbal Sahni Institute of Palaeobotany, , 53, University Road, Lucknow-226 007) : Cenozic coralline algal assemblage from southwestern Kutch and its importance in palaeoenvironment and palaeobathymetry. Curr Sci 2002, 83(2), 153-8.

Little contribution has been made on the study of coralline algae from the cenozoic sediments of south-western Kutch. Some of the limestone units belonging to oligocene and Miocene sediments of southwestern Kutch were known to be potential sources for the recovery of coralline algae. There are some reports on the occurrence of coralline red algae from the early Oligocene, late Oligocene and early Lower Miocene rocks of southwestern Kutch. Taxonomic revision of majority of these taxa needs to be made following the diagnostic characters used in present-day taxonomy. Presently, the extinct coralline algae are being studied based on new anatomical characters applicable to extant coralline algae. The study has been carried out following current methodology of taxonomic consideration on freshly collected samples from the late Oligocene (Chattian) limestone belonging to Bermoti Member of Maniyara For Formation. The assemblage is dominated by the genera Lithophyllum and Mesophyllum. Both these taxa have bveen analysed with the concept of open nomenclature. Attempts have been made to interpret the palacoenvironment and palaeobathymetry based on the analysis of recovered algal assemblage. The distribution pattern of coralline red algae recorded so fat from the Cenozoic sediments of southwestern Kutch has been summarized.

3 illus, 2 tables, 30 ref

021545   Ganesan V V;Mohanan P N;Dikshit S K (Surface Instruments Division, India Meteorological Department, Pune-411 005) : Recent increased seismic activity over Indian peninsular region. Proc TROPMET Natl Symp 2001, (NULL), 100-10.

The Deccan Plateau was usually considered as a stable block, free from earthquakes. But, the moderate earthquake at Latur-Osmanabad in which thousands of people perished and a series of slight earthquakes felt in the Koyna-Nagar region of South Western Maharashtra shattered this belief. Recently, more than 60 to 65 reportable earthquakes were recorded by the seismography at Pune during the period from 5 sept., 2000 alone. An attempt has been made to study the cause of sudden spurt in the activity and a plausible explanation explored.

8 illus, 4 tables, 6 ref

021544   Ganer D W;Deo A A;Salvekar P S (NO, Indian Institute of Tropical Meteorology, Pune-411 008) : The impact of different wind forcings on the mixed layer depth in the tropical Indian ocean. Proc TROPMET Natl Symp 2001, (NULL), 329-35.

An attempt is made to study the spatial and temporal variability in the mixed layer depth (MLD) on seasonal and inter-annual time scale over north Indian Ocean (north of 30S), using a 2 1/2 layer, thermodynamic ocean model. Three different surface wind forcings, viz. NCEP, SSM/I and FSU are used a input, with the NCEP heat flux as a thermal forcing common to all wind forcings, in three different experiments. In all the three cases the model is integrated from 1st January 1992 to 31 st December 1996, from it's steady state. Five years averaged monthly mean climatology of mixed layer depth shows the deep mixed layer in (i) the southern hemisphere during monsoon months (Jan-Sept.). (ii) the Arabian Sea and Bay of Bengal during winter months (Dec-Mar). Further, the time series of area averaged mixed layer thickness over (i) southern hemisphere region shows annual oscillation, with maxima in July, (ii) Arabian Sea shows semi-annual oscillation, with primary maxima in January and secondary in July and (iii) Bay of Bengal shows enhanced variability on shorter time scale, with maximum depth in January.

5 illus, 1 table, 5 ref

021543   Dutta S;Prakash Rao G S (India Meteorological Department, , Shivaji Nagar, Pune) : Diurnal and spatial variation of stability parameters at coastal stations along the East coast, during BOMBEX- 1999. Proc TROPMET Natl Symp 2001, (NULL), 336-46.

An attempt has been made to examine the diurnal variation of some thermodynamic parameters at the coastal stations and spatial variations between them, along East Coast during BOBMEX 1999 period. The study uses the RS data of Calcutta and Visakhapatnam during BOBMEX 1999 period. Level of free Convection (LFC), Level of neutral buoyancy (LNB) Convective available potential energy (CAPE), COnvective inhibition energy (CINE), Moist static energy (MSE) have been computed at all the four synoptic hours for Calcutta and Visakhapatnam during BOMMEX-1999 period. The analysis of the computed parameters provides useful insight into the atmospheric structure in the coastal belt of the Bay of Bengal. The study shows that, there is diurnal variation in all the thermodynamic parameters, viz, LFC, LNB, CAPE, CINE, MSE at both the stations Calcutta and VIsakhapatnam. For both the stations the value of MSE was found to be highest at 0600z. The highest positive value of CAPE was found to be in the afternoon for Calcutta. The study also shows that the negative value of the CINE is very much sensitive to the location of LFC, whereas, the positive value of CAPE is very much sensitive to the upper level buoyancy force and the location of LNB (if available).

3 illus, 2 tables, 6 ref

021542   Dugam S S;Kakade S B (Indian Institute of Tropical Meteorology, , Pune-410 008) : Cyclonic storms in association with ENSO and NAO. Proc TROPMET Natl Symp 2001, (NULL), 50-2.

Analaysis of the decadal scale variability of cyclonic storms and its relationship with the North Atlantic oscillation (NAO) and Southern Oscillation (SO) is carried out. The analysis has been carried out for 108 years (1891-1990) data. From the analysis it has been noticed that decadal frequency of cyclonic storms over Indian Ocean shows a statistically significant negative relationship with winter (December-January-February) NAO. The correlation coefficient between NAO and frequency of cyclonic storms is significant at 1% level. The analysis of the frequency of cyclonic storms on decadal scale with witner SO reveals a positive relationship and it is significant at 1% level.

2 illus, 9 ref

021541   Desai D S;Kulkarni B (Meteorological Office, , Pune-5) : Hiatus in northern limit of monsoon and its impact on monsoon. Proc TROPMET Natl Symp 2001, (NULL), 111-32.

After the onset of monsoon over Kerala, the further advance of the monsoon over India depends upon many synoptic features. The synoptic features change every year and the further advance of the monsoon also changes every year. Therefore, the charts showing the Northern Limit of Monsoon (NLM) are prepared every year. In some years. Northern Limit of Monsoon moves fast and in other years it remains stationary over a place for many days. The period and place where Northern Limit of Monsoon remains stationary is defined as Hiatus in Northern Limit of Monsoon (HNLM). HNLM is a most important feature of monsoon flow and monsoon rainfall. Study of HNLM and its impact on different aspects of monsoon during the last four decades (1960-2000) are presented.

5 illus, 4 tables, 1 ref

021540   Deb G (Geological Studies Unit, Indian Statical Institute, Calcutta-700 035) : Fold-geometry in the Chanda limstone of the proterozoic penganga group of the Pranhita-Godavari valley, and its origin. Indian J Earth Sci 2000, 27(1-4), 11-14.

The Proterozoic Penganga Group of rocks occurring in the Pranhita-Godavari Valley is generally considered undeformed. Recent studies reveal that the Chanda Limestone of the Penganga Group preserves secondary structures including shear fractures and fault-related folds. The geometry of the structures is consistant with their origin by horizontal lateral compression. Shearfractures, commonly occurring in conjugate sets, were produced at the initial stage of layer-parallel shortening. relations among small-scale shear fractures and folds suggest that continued compression led to bucking of the limestone beds. Two sets of folds with the NW-Se and ENE-WSW axial trends are developed, and locally thier interference has resulted in dome-basin pattern. The orientation pattern indicates that through the development of the NW-SE trending fold sets was initiated slightly earlier than the other set, the growth of the two fold sets was broadly simultaneous, and under predominantly NE-SW directed compressio. The structures in the Chanda Limestone could possibly be the manifestation of tectonic inversio of the Pranhita-Godavari Valley.

5 illus, 5 ref

021539   Das M R;Sarkar J;Jaswal A K (India Meteorological Department, , Pune-5) : Seasonal distribution of Cloudy days over India North of Latitude 20°N. Proc TROPMET Natl Symp 2001, (NULL), 196-9.

From the isopleth analysis of normals of number of cloudy days plotted on the charts, the following salient features are revealed. In January, northwest parts of India have 8 or more cloudy days. As one moves from Sub-Himalayan West Bengal eastwards, these days increase, maximum being over Brahmaputra valley. Region of maximum and iminum cloudiness appear alternately in the latitudinal belt of 22-25°C N. In April, east of longitude 87° E number of cloudy days increases along the sub-montane regions from west to east. Number of cloudy days is maximum (≥20) over extreme northeast India; another maximum (<62> 12) lies over Jammu & Kashmir and adjoining Himachal Pradesh. Number of cloudy days extends from Bangladesh to Gangetic West Bengal and north coastal Orissa in the form of a tongue. It is minimum (<60>6) over Manipur and adjoining areas of Nagaland and Mizoram. In July, the isoline 24 cloudy days or more covers the region north of latitude 25°N and east of 85°E and also south of latitude 24°N, west of east coast and east of longitude 74°E. Between these two regions lie two belts of minimum cloudiness. These belts lie more or less along the normal position of southwest-monsoon trough line. Along the foothills of Himalayas and south of the above belts lie the pockets of maximum and minimum cloudiness in an alternate fashion.

4 illus, 10 ref

021538   Das I;Mohan M;Krishna Moorthy K (Atmospheric Sciences Division, MOG, Space Applications Centre, Ahmedabad) : Characterisation of marine aerosols using IRS P4-OCM Data. Proc TROPMET Natl Symp 2001, (NULL), 415-18.

Using the bands 7 and 8 (765nm and 865 nm respectively) radiance data of IRS P4 - OCM, optical depth (AOD) of aerosols over the oceans are derived over the coastal regions of India. The retrieval algorithm computers the aerosol parameters by treating the ocean surface as a dark background and after removing the contribution from the atmospheric Reyleigh scattering in the sensor detected radiances. The satellite detected AOD shows agreement with the ground based sun photometer measurements carried out at Trivandrum. Comparisons of the OCM derived AOD over the Arabian sea with the NOAA aerosol operational products shows a correlation <126> 0.85. An algorithm for the study of long term variations of marine aerosols using OCM data is being developed. With this, the monthly climatology of aerosol parameters will be produced for a set of selected areas over the coastal regions of India.

3 illus

021537   Das D K;Sindhu J (Division of Agricultural Physics, Indian Agricultural Research Institute, New Delhi-110 012) : Importance of weather forecasting in Agriculture. Fertil News 2001, 46(12), 89-90, 95-9, 10.

Weather is a major uncontrolled driving force of agricultural production. It affects every production management practices from seedbed preparation to harvest. Accurate weather forescast plays vital role not only in planning and timely agricultural operations, but also helps in adopting alternate strategies for efficient use of inputs and in minimizing crop losses due to aberrant weather. Presents the different types of weather forecasts and their application, the past and presents status weather forecasts in India and status of forecasts in other developed and developing countries. The imortance of weather forecasts in various spheres of agricultue. With changing agricultural scenario and advances in technologies like remote sensing and GIS, the future role and development needed in weather forecasting systems and its dissemination for sustainable agricultural development are highlighted.

2 illus, 1 table, 65 ref

021536   Chatterjee A;Bandopadhyay S;Bhattacharya H N (Dept of Geology, Presidency College, Calcutta-700 073) : Progressive development of structures in a ductile shear zone along a part of the Cuddapah Basin, India. Indian J Earth Sci 2000, 27(1-4), 33-9.

The quartzite - mice schist alternations representing the easternmost edge of the Proterozoic Cuddapah Basin, are exposed between Vinukonda and Ipur, Guntur district, Andhra pradesh, India. The rock units record folds that represent progressive shear related deformation. With the help of the available kinematic model of ductile shear zone, reclined folds of different generations, subhorizontal folds and upright cross-folds are analysed. The nature of deformation along the eastern margin of Cuddapa Basin is flattening type as evidenced from the two dimensional boundinage.

9 lus, 16 ref

021535   Charlotte B V;Mathew B;Kurup P G (Department of Physical Oceanography, School of Marine Sciences, Cochin University of Science & Technology, Cochin-682 016) : SST Anomalies in the Indian ocean during strong and weak monsoons. Proc TROPMET Natl Symp 2001, (NULL), 258-62.

The monthly mean sea surface temperature (SST) anomalies (Data source: COADS) in the Indian Ocean region (30°E - 100°E; 30°S - 25°N) during contrasting monsoon years are studied. In general, monthly mean SST anomalies are weak (<60>0.5°C) in the Northern Indian Ocean while it is larger (<62>1°C) in the region south of 15°S. The study suggests no relationship between pre - monsoon (March and April) SST anomalies and the performance of monsoons. Positive SST anamalies persisted in the Indian Ocean during pre - monsoon in some bad monsoon years (eg. 1979, 1987) and also in some excess monsoon years (1961,1988) whereas negative SST anomalies persisted in the pre - monsoon in some deficient monsoon years (1951, 1965, 1972) and also in strong monsoon years (1956, 1975). However, the SST anomalies during post - monsoon (October) show good relationship with the monsoon activity, especially in the northern Indian Ocean. SST anomalies during post-monsoon are found to be negative in excess monsoon years and positive in weak monsoon years, throught the magnitudes are found to vary from year to year.

2 illus, 10 ref

021534   Chandrasekhara Rao P (Regional Meteorolgical Centre, , Chennai) : Effect of storms and depressions on the Rainfall of Rayalaseema. Proc TROPMET Natl Symp 2001, (NULL), 184-8.

Northeast monsoon seasonal rainfall of Rayalaseema sub-division is considerably dependent or altered by some of the cyclones and depressions of Bay of Bengal that cross the coast between 10 and 16 degrees North. After crossing the coast, these systems pass over the region either weakening gradually or dissipating over the region. During this period, at least two to three of the four districts of Rayalaseema receive considerable rainfall that amounts to a bulk of season's normal. Discusses in detail, the effect of these storms and depressions on the rainfall districts of Rayalaseema sub-division during northeast monsoon season and in turn on the annual rainfall. The effect of El Nino on the rainfall of the region has also been studied and the results are discussed. No significant correlation has been found between El Nino and monsoon rainfall of Rayalaseema.

2 illus, 3 tables, 2 ref

021533   Chandra S (NO, Jawaharlal Nehru University, New Delhi-110 067) : Regional development of Gondwana sedimentation in India: framework minerals in sandstones. Indian J Earth Sci 2000, 27(1-4), 15-32.

425 sandstone samples from the Gondwanas all over India are analysed. Important composition differences in space and time are highlighted. A broad distinction in the regional development of Gondwana sedimentation emerges sharply along with local variations. Plate motion during the Permain is not much sensed. Rather an uneven unroofing from multiple provenances is corroborated at times in some detail. Acknowledged gaps in the analysis need an urgent followup to settle the issue.

16 illus, 5 tables, 14 ref