Operational Real Time Quantitative Rainfall Forecasts at Hobli-Level over Karnataka State
IR@C-MMACS: CSIR-Centre for Mathematical Modelling and Computer Simulation, Bangalore
View Archive Info| Field | Value | |
| Title |
Operational Real Time Quantitative Rainfall Forecasts at Hobli-Level
over Karnataka State
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| Creator |
Goswami, P
V, Rakesh Patra, G K |
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| Subject |
Climate Modelling
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| Description |
Advance and accurate forecasts of rainfall can aid many sectors, from agriculture to disaster mitigation.
However, for effective application, such forecasts must be at relevant spatial scales; given the tremendous
spatial variability of rainfall, only forecasts at high resolution can serve the user’s need. Worldwide, such highlevel
rainfall forecasting is in its infancy. It is recognized that scientific inputs through sustained evaluation,
supplemented by region-specific customization, are necessary for improvement of the current level of skill in
high-resolution forecasting. To create a science-based platform for advance and accurate forecast at relevant
scales through such scientific efforts and interactive evaluation, CSIR Centre for Mathematical Modelling and
Computer Simulation (C-MMACS) and Karnataka State Natural Disaster Monitoring Centre (KSNDMC, Govt
Karnataka) have embarked upon a programme aimed at generating rainfall forecasts at the hobli-level. The goal
of the programme is to generate and disseminate forecasts customized to user needs and applications, such as
irrigation schedule and crop insurance. The most commonly used current strategy for high-resolution forecasting
is to use Limited Area Models (LAM), three dimensional models of the atmospheric dynamics. The strength of
these models is their ability to resolve surface forcings such as orography, vegetation and convective dynamics
at scales not yet feasible in General Circulation Models (GCM). However, it is recognized that off-the-shelf
models can not be expected to provide useful skill. World over, dynamical meso-scale forecasting is an evolving
technology, with many challenges. The challenges grow as the spatial scale of the forecast is reduced; indeed,
advance forecasting at hobli-level has not yet been tried in India. We have used a state-of-the-art LAM, called
Weather Research and Forecasting (WRF) Model, calibrated for meso-scale forecast over Karnataka. The
calibration and optimization were carried out based on methodologies developed at C-MMACS as well as
elsewhere. The forecasts are generated using the C-MMACS High-Performance Computing Platform, and issued
twice daily (morning and afternoon) through an Industrial Partner of C-MMACS (M/S Frontier Pusher); these
forecasts are disseminated to various users by KSNDMC. Here we present an evaluation of real-time 24-h
quantitative precipitation forecasts at hobli-level over Karnataka for the northeast monsoon season (October-
December) of 2010. A statistical evaluation of the forecasted rainfall at hobli-level is carried out by comparing
with the observations from the telemetric rain-gauge network established by KSNDMC. In addition, data from a
variety of sources, including the CSIR Climate Observation and Modelling Network (COMoN) is used to improve
the forecast through assimilation of local data. Several measures of forecast quality are used to evaluate the
forecast skill. The objective at present is to provide accurate forecasts of rainfall category rather than the precise
amount. The results show that forecasts capture the spatio-temporal variability in observed rainfall over
Karnataka well enough to be useful. At the same time, certain areas of systematic bias are identified for further
calibration to improve forecast skill over these areas.
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| Publisher |
CSIR Centre for Mathematical Modelling and Computer Simulation
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| Date |
2011-07
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| Type |
Monograph
NonPeerReviewed |
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| Format |
application/pdf
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| Identifier |
http://cir.cmmacs.ernet.in/178/1/rrcm1102%2D1.pdf
Goswami, P and V, Rakesh and Patra, G K (2011) Operational Real Time Quantitative Rainfall Forecasts at Hobli-Level over Karnataka State. Technical Report. CSIR Centre for Mathematical Modelling and Computer Simulation, C-MMACS and KSNDMC, Bangalore. (Unpublished) |
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| Relation |
http://cir.cmmacs.ernet.in/178/
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