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Abhilash, S.
- Real-Time Performance of a Multi-Model Ensemble-Based Extended Range Forecast System in Predicting the 2014 Monsoon Season Based on NCEP-CFSv2
Abstract Views :338 |
PDF Views:145
Authors
A. K. Sahai
1,
R. Chattopadhyay
1,
S. Joseph
1,
R. Mandal
1,
A. Dey
1,
S. Abhilash
1,
R. P. M. Krishna
1,
N. Borah
1
Affiliations
1 Indian Institute of Tropical Meteorology, Pune 411 008, IN
1 Indian Institute of Tropical Meteorology, Pune 411 008, IN
Source
Current Science, Vol 109, No 10 (2015), Pagination: 1802-1813Abstract
The real-time validation of any strategy to forecast the Indian summer monsoon rainfall requires comprehensive assessment of performance of the model on sub-seasonal scale. The multi-model ensemble (MME) approach based on the NCEP-CFS version 2 models, as developed and reported earlier, has been employed to forecast the 2014 monsoon season on the extended range scale with 3-4 pentad lead time (where a pentad corresponds to five-day average). The present study reports the broad performance of the MME employed on experimental basis to forecast the salient features of the real-time evolution of the 2014 monsoon season during June to September. The MME is successful in predicting both these features well in advance (3-4 pentad or 15-20 days lead time). The assessment of the model performance at pentad scale lead time shows that the weak monsoon conditions that are evident in precipitation and lower level wind anomalies are well captured as a whole up to four pentad advance lead time. The subseasonal propagation during onset and withdrawal is also evident in the forecast. Finally, the region-wise performance shows that the spatial extent of the skillful forecast encompasses central India as well as the monsoon zone for the 2014 monsoon season. Considering the natural variation in the forecast skill of extended range forecast itself as reported in earlier studies, the 2014 monsoon forecast seems to be skillful for operational purposes. For other regions (e.g. North East India), the forecast could be skillful at times, but it still requires further research on how to improve the same.Keywords
Monsoon Forecast, Multi-Model Ensemble, Pentad, Lead Time.Full Text
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- A Versatile 205 MHz Stratosphere–Troposphere Radar at Cochin – Scientific Applications
Abstract Views :472 |
PDF Views:138
Authors
K. Mohanakumar
1,
K. R. Santosh
1,
P. Mohanan
1,
K. Vasudevan
1,
M. G. Manoj
1,
Titu K. Samson
1,
Ajil Kottayil
1,
V. Rakesh
1,
Rejoy Rebello
1,
S. Abhilash
1
Affiliations
1 Advanced Centre for Atmospheric Radar Research, Cochin University of Science and Technology, Cochin 682 022, IN
1 Advanced Centre for Atmospheric Radar Research, Cochin University of Science and Technology, Cochin 682 022, IN
Source
Current Science, Vol 114, No 12 (2018), Pagination: 2459-2466Abstract
A state-of-the-art, indigenously developed, and the world’s first 205 MHz stratosphere–troposphere (ST) wind profiler radar installed at the Cochin University of Science and Technology, Kerala, with the support of Science Engineering Research Board, Department of Science and Technology, Government of India, is introduced in this article. This radar provides a cost-effective and high precision technology capable of monitoring in all weather conditions round the clock. Its primary goal is to understand the characteristics of the Indian summer monsoon at its gateway at Cochin. Brief technical details and the validation of radar data with the colocated GPS radiosonde observations are mentioned. Applications of the ST radar data for various studies of atmospheric, ionospheric and radio astronomical features are discussed. Cochin ST Radar is open to all researchers from national institutes, universities and other academic institutions for conducting regular as well as special experimental campaigns, based on their scientific proposals.Keywords
Atmospheric Waves, Monsoon, ST Radar, Turbulence, VHF Radar.Full Text
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