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Indian Journal of Radio & Space Physics (IJRSP) >
IJRSP Vol.39 [2010] >
IJRSP Vol.39(2) [April 2010] >
| Title: | Nowcasting of Yes/No rain situations at a station using soft computing technique to the radar imagery |
| Authors: | Dutta, Devajyoti
Sarma, Diganta Kumar
Konwar, Mahen
Sharma, Sanjay
Viswanathan, G
Gairola, R M
Das, J
Kannan, B A M
Venkateswaralu, S |
| Keywords: | Doppler weather radar (DWR)
Image processing
Artificial neural network (ANN)
Multilayer perception
Rain nowcasting |
| Issue Date: | Apr-2010 |
| Publisher: | CSIR |
| PACS No.: | 92.40.eg; 92.60.jf; 84.40.Xb |
| Abstract: | A soft computing
model for nowcasting of Yes/No rain situations, with a lead time of 2 h, is
developed over DWR station at Satish Dhawan Space Centre (SDSD), Shriharikota
(13.66°N, 80.23°E) using Doppler weather radar (DWR) reflectivity imageries. Primarily,
precipitating systems of mesoscale, i.e. meso-gamma (2-20 km), meso-beta
(20-200 km) and meso-alpha
(200-2000 km) are considered for the present study. The main components of soft computing approach are:
analysis of two-dimensional reflectivity imageries from DWR and utilization of
artificial neural network (ANN) for training of input/output data. About 15
input and one output parameters are extracted from radar imageries. The image analysis
and training of ANN are carried out on MATLAB platform. After training of ANN,
91 and 77% results are matched with the observed values for No rain and Yes
rain situations, respectively. The probability of detection (POD) for the
nowcasting of Yes/No rain situations is found to be 0.84. The significant
improvement in the nowcasting of Yes/No rain situations is observed by the
developed methodology as compared to linear multivariable regression method.
The POD of Yes/No rain for other two locations, namely Chennai (12.99°N, 80.18°E)
and Tiruvallur (13.09°N, 79.57°E) are found to be 0.81 and 0.77, respectively.
Overall, reasonably good results are obtained by the newly developed soft
computing model. |
| Page(s): | 92-102 |
| ISSN: | 0975-105X (Online); 0367-8393 (Print) |
| Source: | IJRSP Vol.39(2) [April 2010]
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