Sub-Mesoscale Circulation Features along the Andhra Pradesh Coast, Bay of Bengal: Observations from HF Radars

2020 ◽  
Vol 89 (sp1) ◽  
pp. 132
Author(s):  
Samiran Mandal ◽  
Saikat Pramanik ◽  
Sourav Sil ◽  
Kondetharayil Soman Arunraj ◽  
Basanta Kumar Jena
2012 ◽  
Vol 62 (2) ◽  
pp. 613-633
Author(s):  
G. R. Chinthalu ◽  
T. Dharmaraj ◽  
A. R. Dhakate ◽  
P. C. S. Devara

MAUSAM ◽  
2021 ◽  
Vol 60 (1) ◽  
pp. 25-38
Author(s):  
M. MOHAPATRA ◽  
U. C. MOHANTY

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.


Zootaxa ◽  
2020 ◽  
Vol 4890 (1) ◽  
pp. 135-147
Author(s):  
K.V. AKHILESH ◽  
T.G. KISHORE ◽  
M. MUKTHA ◽  
M.W. LISHER ◽  
GOP P. AMBARISH ◽  
...  

Pseudanthias vizagensis Krishna, Rao and Venu, 2017 was described from 44 specimens, collected from Visakhapatnam (Andhra Pradesh), on the Bay of Bengal coast of India, but without clear designation of a holotype. The characters used for differentiating the species from its nearest congener Pseudanthias pillai Heemstra & Akhilesh, 2012, a species currently known only from the northern Indian Ocean, were limited, poor and substantially overlapping. Examination of additional material of P. pillai from the Arabian Sea, Bay of Bengal, Andaman Sea, and comparison with the original description and images of P. vizagensis revealed that the latter is a junior synonym of P. pillai. Diagnostic characters are reviewed, additional morphological details and fresh colouration, including sexual dimorphic characters not covered in previous works are provided. 


2007 ◽  
Author(s):  
S. Ramalingeswara Rao ◽  
K. Muni Krishna ◽  
Bhanu Kumar
Keyword(s):  

Author(s):  
Sujatha Peela ◽  
Swethalatha Porana

Objective: The Objective of this research is to isolate and screen potent antibiotic producing actinomycetes from unexplored regions of Bay of Bengal Near Srikakulam Coast.Methods: The isolation and screening were done on starch casein agar media. Antimicrobial activity screening was done using cross streak method and agar diffusion method. Further, Morphological characterization of the isolate was done using Scanning electron Microscopy (SEM-JSM 6610). Further, the cultural characterization of the isolates was done using standard protocols.Results: A total of sixty-eight isolates of Actinomycetes were collected from marine sediments of coastal line of Srikakulam district of Andhra Pradesh, which is one of the longest coastal lines of Andhra Pradesh. Due to its longest coastal line and geographical distribution, there are promising chance of diversity of the microorganisms and antibiotic producing potential. Each isolate was tested against various bacteria. Among all the isolates twelve isolates were promising and showed good antimicrobial activity. Within twelve isolates the isolate A-10 was very promising and showed antibiotic potential against most of the tested bacteria. This isolate appears to produce high anti-bacterial compounds on potato dextrose agar and nutrient agar medium respectively by using the agar diffusion method. The potent Actinomycete A-10 was further characterised by morphological methods consist of macroscopic and microscopic methods. The mycelium structure, colour and arrangement of conidiophores were observed through the oil immersion (100X). The strain was grown on Starch-Casein agar medium for morphological study using Scanning Electron microscopy. Scanning Electron micrographs of the strain A-10 results that the spore chain was straight and with more than 20 spores per chain. The spores are cylindrical in shape and had a smooth surface. Whirls, sclerotic granules, sporangia and flagellate spores were not observed. Further various biochemical tests performed for the identification of potent isolates are as follows: Melanin reaction, H2S production, tyrosine reaction, starch hydrolysis, casein hydrolysis, gelatin hydrolysis, milk coagulation and peptonization, nitrate reduction, temperature range of growth, pH tolerance and cell wall type by comparing all these results with the Bergey’s manual of Determinative Bacteriology and the organisms were identified. The isolate was identified as Streptomyces sp.Conclusion: Thus the result of antibacterial screening represents that the coastal area of Srikakulam is a potential source of antibiotic producing actinomycetes. Further the phylogenic tree construction and purification of the antibiotic principle from A-10 were under investigation.Keywords: Actinomycetes, Marine Sediments, Starch-Casein agar, SEM


MAUSAM ◽  
2021 ◽  
Vol 60 (2) ◽  
pp. 167-174
Author(s):  
O. P. SINGH

The paper 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. The results show intensification of storms during May-June and September-November. The monsoon depressions  during July-August are  likely to become less intense.   In GHG experiment most of the post-monsoon storms have a tendency to strike north Andhra-Orissa coasts whereas in CTL experiment the storms strike coast from Tamilnadu to south Orissa. Thus, the focus of post-monsoon storms in the BOB is likely to shift northwards from Tamilnadu-Andhra Pradesh coast to north Andhra Pradesh-south Orissa coast. Another important simulated change in storm tracks is that more number of pre-monsoon storms in the BOB may have a tendency to recurve north or northeastwards by 2041-2060.


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