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We report the spatio-temporal variability of surface-layer turbulent fluxes of heat, moisture and momentum over the Bay of Bengal (BoB) and the Arabian Sea (AS) during the Integrated Campaign for Aerosols, gases Radiation Budget (ICARB) field experiment. The meteorological component of ICARB conducted during March – May 2006 onboard the oceanic research vessel Sagar Kanya forms the database for the present study. The bulk transfer coefficients and the surface-layer fluxes are estimated using a modified bulk aerodynamic method, and then the spatio-temporal variability of these air-sea interface fluxes is discussed in detail. It is observed that the sensible and latent heat fluxes over the AS are marginally higher than those over the BoB, which we attribute to differences in the prevailing meteorological conditions over the two oceanic regions. The values of the wind stress, sensible and latent heat fluxes are compared with those obtained for the Indian Ocean Experiment (INDOEX) period. The variation of drag coefficient (CD), exchange coefficients of sensible heat and moisture (CH = CE) and neutral drag coefficient (CDN) with wind speed is also discussed.

A simulation study of the sea breeze circulation and thermal internal boundary layer (TIBL) characteristics has been carried out at the tropical site Kalpakkam on the east coast of India, for operational atmospheric dispersion prediction. The community based PSU/NCAR MM5 Meso-scale meteorological model is used for the study. Three cases on typical days in summer (24 May 2003), southwest (SW) monsoon (1 July 2001) winter season (2 February 2003) with different large-scale flow pattern are studied. The MM5 model is used with 3 nested domains with horizontal grid resolutions 18 km, 6 km and 2 km and 26 vertical levels. The model is integrated for 24 hours in the above cases with initial and boundary conditions taken from NCEP-FNL analyses data. Observations of 10 meteorological stations and coastal boundary layer experiments conducted at Kalpakkam are used for comparison and validation of the simulation. The characteristics of simulated sea breeze and TIBL at Kalpakkam are seen to vary in the above cases according to the prevailing large-scale winds and surface fluxes. The sea breeze circulation is seen to develop early with larger strength and inland propagation in the summer case under the influence of moderate synoptic wind and strong heating conditions than in the SW monsoon and winter cases. The horizontal and vertical extents of TIBL are found to be larger in the summer case than in other cases. Although model parameters agree in general with observations, all the fine features are not clearly captured and some slowness in model sea breeze development is also seen. The results indicate the need to improve i) the initial conditions by assimilation of available surface/upper air observations to reduce model bias and ii) surface net radiation parameterisation. The model could predict the essential features of the local circulation and further improvement is expected with better initial condition data and incorporation of more realistic surface data.

A phased array Doppler Mini-Sodar has been installed at Anupuram near Kalpakkam nuclear site during the Coastal Atmospheric Boundary Layer Experiments (CABLE) carried out on the east coast of India. Mini-Sodar was used to measure the wind profile and investigate the coastal boundary layer development due to land-sea breeze circulation for the study of coastal dispersion of pollutants. The atmospheric boundary layer, its variability during SW (August 13, 14 : ARMEX I and September 3, 7, 11, 14) and pre-monsoon period (April 27, 28 : ARMEX II) 2003 has been studied. Large wind direction change and high vertical velocity variance were observed during the onset of sea breeze. The Thermal Internal Boundary Layer (TIBL) height has been found to increase progressively with season: summer - 170 m, SW monsoon - 210 m and NE monsoon - 325 m whereas the Nocturnal Boundary Layer (NBL) height decrease progressively during the corresponding period: summer - 370 m, SW monsoon - 340 m and NE monsoon - 210 m.

The conventional gamma camera used for the assessment of lymphatic system, using the lymphoscintigraphy technique, is institution based and costly. Therefore, it is not easily accessible to people from remote rural areas. Hence, there is a need for economical and portable equipment to field survey disease‐prone areas. Towards this objective, with the advent of developments in radioactivity detection techniques, knowledge‐based instrumentation, computer technology, a versatile, cost‐effective, portable microcontroller based scintillation detector equipment with a personal computer (PC) interface for the assessment of the lymphatic system has been designed and developed using a lymphoscintigraphy technique. Though the technique is conventional, the detection of radioactivity is unique, employing micro scintillation detectors in contrast to conventional gamma camera. In the latter case, a large diameter scintillation detector is allowed to scan the area of interest for a predetermined time to produc...

Detailed measurements were carried out in the Marine Atmospheric Boundary Layer (MABL) during the Integrated Campaign for Aerosols, gases and Radiation Budget (ICARB) which covered both Arabian Sea and Bay of Bengal during March to May 2006. In this paper, we present the meteorological observations made during this campaign. The latitudinal variation of the surface layer turbulent fluxes is also described in detail.