Performance of 4D-Var Data Assimilation on Extreme Snowfall Forecasts over the Western Himalaya Using WRF Model

Narasimha Rao Nalamasu,M S Shekhar,GP Singh 한국기상학회 2021 Asia-Pacific Journal of Atmospheric Sciences Vol.57 No.3

The accurate predictions of extreme precipitation/snowfall events are very helpful in identifying the severe avalanche/landslide prone hazard areas in advance over high mountainous regions. The Weather Research and Forecasting model (WRF) version 3.9 has been used to investigate the performance of Four-Dimensional Variational data assimilation (4D-Var) on Three-Dimensional Variational data assimilation (3D-Var) by considering two extreme snowfall events (23–26 January 2017 and 05–08 February 2019) over the Western Himalaya (WH). The result shows that the 4D-Var performed better than the 3D-Var for both the events by analyzing domain-averaged error and sensitivity parameter analysis. The initial state model variable’s domain-averaged error analysis revealed that 4D-Var has great potential to improve the initial conditions than the 3D-Var from lower to the upper atmosphere. Sensitivity parameter analysis also supports 4D-Var has more sensitive than the 3D-var especially in the lower and upper atmosphere by changing temperature and moisture fields along with winds circulations. From statistical skill scores analysis, 4D-Var performed well to reproduce the extreme snowfall events than the 3D-Var over WH.

Spore Shedding in Catenella impudica from the Godavari Estuary at Bhiravapalem, India

Narasimha Rao, G. Mohan,Rangaiah, G. Subba,Dora, S. V. V. S. N. The Korean Society of Phycology 2008 ALGAE Vol.23 No.1

Catenella impudica (Mont.) J.Ag is an important species for human consumption from estuarine regions of Asia. Seasonal shedding of carpospores and tetraspores was quantified between January and December 2004 for natural populations of C. impudica. Vegetative and tetrasporophytic plants were available throughout the year but gametophytic plants were observed only from September to May. Tetraspore shedding was observed throughout the year and carpospores shedding was noticed only during the months when material was available. Hydrographical conditions of the estuary such as low water temperature and low salinity are correlated to the formation and release of carpospores and tetraspores in C.impudica

Spore Shedding in Catenella impudica from the Godavari Estuary at Bhiravapalem, India [Note]

G. M. Narasimha Rao,S.V.V.S.N. Dora,G. Subba Rangaiah 한국조류학회I 2008 ALGAE Vol.23 No.1

Catenella impudica (Mont.) J.Ag is an important species for human consumption from estuarine regions of Asia. Seasonal shedding of carpospores and tetraspores was quantified between January and December 2004 for natural populations of C. impudica. Vegetative and tetrasporophytic plants were available throughout the year but gametophytic plants were observed only from September to May. Tetraspore shedding was observed throughout the year and carpospores shedding was noticed only during the months when material was available. Hydrographical conditions of the estuary such as low water temperature and low salinity are correlated to the formation and release of carpospores and tetraspores in C.impudica

Development of New Robust Bivoltine Silkworm Hybrid $SR2{\times}SR5$ for Rearing throughout the Year

Rao, P. Sudhakara,Nayaka, A. R. Narasimha,Mamatha, M.,Sowmyashree, T. S.,Bashir, Ifat,Ilahi, Irfan Korean Society of Sericultural Science 2007 International Journal of Industrial Entomology Vol.14 No.2

A Silkworm breeding programme was designed to develop a robust but productive bivoltine silkworm hybrid of Bombyx mori L. suitable for rearing throughout the year in tropical climate by utilizing indigenous polyvoltine and productive bivoltine breeds. The breeding was carried out under high temperature ($36^{\circ}C{\pm}1^{\circ}C$) and low humidity ($50{\pm}5%$) conditions in the environmental chamber. By $F_{12}$, three oval and three dumbbell breeds were isolated with higher survival and productive merits. These breeds were utilized in the hybrid evaluation along with other popular breeds. Based on combining ability test results, the hybrid $SR_2{\times}SR_5$ was selected for large scale testing and evaluated in different seasons. The evaluation studies indicated that the hybrid has higher viability and productive merits and it is suitable to rear throughout the year. The hybrid $SR_2{\times}SR_5$ recorded a survival of 92.0%, cocoon shell weight of 0.417 g, cocoon shell percentage of 23.0 and a filament length of 1042 meters under hot and dry conditions of environmental chamber compared to the control thermo-tolerant hybrid $CSR18{\times}CSR19$.

Effect of Phytoecdysteroid on Disease Incidence, Melting and Economic Characters of the Mulberry Silkworm

Kar, Mithilesh,Rao, P. Sudhakara,Kishore, S.,Kumar, T. Selva,Gopal, Nisha,Nayaka, A.R. Narasimha,Chandrasekaran, K. Korean Society of Sericultural Science 2009 International Journal of Industrial Entomology Vol.18 No.1

A study has been made to know the effect of a phytoecdysteroid 'Sampoorna' on uniform maturation of silkworms during spinning and its effect on diseased silkworms infected by major silkworm disease viruses, Bombyx mori nuclear polyhedrosis virus (BmNPV) and Bombyx mori infectious flacherie virus (BmIFV). In the present investigation, the effect of the phytoecdysteroid "Sampoorna" on Grasserie disease caused by BmNPV have shown an average cocoon melting of 11.91% with a disease incidence of 5.83%. The values of 't' test for different treatments of BmNPV indicated low survival rate and cocoon traits were drastically reduced. Another major disease Flacherie caused by BmIFV has shown considerable levels of larval disease incidence (22-32%) and cocoon melting (3-7.67%) with an average melting of 12.95% and 20.24% disease incidence. There is a drastic reduction in survival rate, cocoon yield and other economic traits. The control batches were indicated negligible values for disease incidence and cocoon melting with Sapoorna application and without the inoculation of the two disease-causing viruses. The application of Sampoorna on already infected batches with major pathogens triggered high mortality and disease incidence and melting percentage was also significantly increased with reduced economic traits. Hence, it is suggested that application of Sampoorna in infected batches should be done only in the extreme conditions of rearing. Application of Sampoorna on healthy batches led to uniform maturation and improvement in productivity with the added advantage of better quality cocoons and labour saving.

Development of New Robust Bivoltine Silkworm Hybrid SR2 × SR5 for Rearing throughout the Year

P. Sudhakara Rao,A. R. Narasimha Nayaka,M. Mamatha,T. S. Sowmyashree,Ifat Bashir,Irfan Ilahi 한국잠사학회 2007 International Journal of Industrial Entomology Vol.14 No.2

The Behavior of Laterally Loaded Piles Subjected to Scour in Marine Environment

Y. Nanda Kishore,S. Narasimha Rao,J.S. Mani 대한토목학회 2009 KSCE JOURNAL OF CIVIL ENGINEERING Vol.13 No.6

Pile foundations are used to transmit both vertical and horizontal loads. Many of offshore and coastal structures are founded on piles and these piles are subjected to significant amounts of lateral loads due to wind, wave and currents. Piles in shallow water regions are subjected to scour and there can be loss of soil support around these pile foundations. Bending moments and deflections are increased due to scour. In this investigation, it has been brought out that the lateral capacity of foundation is reduced due to scour. Tests on model piles of PVC and Aluminum embedded in soft marine clay bed formed at different consistency indices and load eccentricity ratios were conducted with and without scour. These pile materials are chosen such that there is a good variation in the rigidity of piles. From the model tests, it is noticed that scour results in the reduction in lateral capacity and increase in bending moments. In the second set of tests, cyclic loading is applied on PVC and Aluminum piles for a time period of 12 seconds. This time period represents the time period of storm wave in across the Indian seas. Considerable increase in deflection occurred due to scour in cyclic load tests for different consistency conditions of soil. Pile foundations are used to transmit both vertical and horizontal loads. Many of offshore and coastal structures are founded on piles and these piles are subjected to significant amounts of lateral loads due to wind, wave and currents. Piles in shallow water regions are subjected to scour and there can be loss of soil support around these pile foundations. Bending moments and deflections are increased due to scour. In this investigation, it has been brought out that the lateral capacity of foundation is reduced due to scour. Tests on model piles of PVC and Aluminum embedded in soft marine clay bed formed at different consistency indices and load eccentricity ratios were conducted with and without scour. These pile materials are chosen such that there is a good variation in the rigidity of piles. From the model tests, it is noticed that scour results in the reduction in lateral capacity and increase in bending moments. In the second set of tests, cyclic loading is applied on PVC and Aluminum piles for a time period of 12 seconds. This time period represents the time period of storm wave in across the Indian seas. Considerable increase in deflection occurred due to scour in cyclic load tests for different consistency conditions of soil.

Effect of Phytoecdysteroid on Disease Incidence, Melting and Economic Characters of the Mulberry Silkworm

Mithilesh Kar,P. Sudhakara Rao,S. Kishore,T. Selva Kumar,Nisha Gopal,A. R. Narasimha Nayaka,K. Chandrasekaran 한국잠사학회 2009 International Journal of Industrial Entomology Vol.18 No.1

A study has been made to know the effect of a phytoecdysteroid `Sampoorna` on uniform maturation of silkworms during spinning and its effect on diseased silkworms infected by major silkworm disease viruses, Bombyx mori nuclear polyhedrosis virus (BmNPV) and Bombyx mori infectious flacherie virus (BmIFV). In the present investigation, the effect of the phytoecdysteroid "Sampoorna" on Grasserie disease caused by BmNPV have shown an average cocoon melting of 11.91% with a disease incidence of 5.83%. The values of `t` test for different treatments of BmNPV indicated low survival rate and cocoon traits were drastically reduced. Another major disease Flacherie caused by BmIFV has shown considerable levels of larval disease incidence (22-32%) and cocoon melting (3-7.67%) with an average melting of 12.95% and 20.24% disease incidence. There is a drastic reduction in survival rate, cocoon yield and other economic traits. The control batches were indicated negligible values for disease incidence and cocoon melting with Sapoorna application and without the inoculation of the two disease-causing viruses. The application of Sampoorna on already infected batches with major pathogens triggered high mortality and disease incidence and melting percentage was also significantly increased with reduced economic traits. Hence, it is suggested that application of Sampoorna in infected batches should be done only in the extreme conditions of rearing. Application of Sampoorna on healthy batches led to uniform maturation and improvement in productivity.