Open Access Open Access  Restricted Access Subscription Access

Reduction in Uncertainty in Tropical Cyclone Track Forecasts over the North Indian Ocean


Affiliations
1 India Meteorological Department, Mausam Bhavan, Lodhi Road, New Delhi 110 003, India
 

Over the North Indian Ocean (NIO) basin, the uncertainty in tropical cyclone (TC) track forecast is depicted by constructing a cone of uncertainty (COU) around the forecast track for the benefit of disaster managers in their decision-making, especially with respect to area of evacuation. The COU is constructed by drawing a tangent to the circles with the radii equal to average track forecast errors during the past five years for forecast times of 12, 24, 36, …, up to 120 h. The COU which is revised periodically to reflect the track forecast accuracy, has been recently revised by India Meteorological Department (IMD) from the post-monsoon season of 2014. Hence, a study has been undertaken to evaluate this newly introduced COU forecast by IMD. The revised radii used to construct the COU have shrunk by 20-30% due to improved TC track forecast in the recent years (2009-2013). For the new COU, the radii of circles for 24, 48, 72, 96 and 120 h forecasts are 65, 105, 140, 170 and 200 nm respectively, against 80, 135, 185, 235 and 285 nm for the previous COU (2009-2013). The accuracy of the newly constructed forecast COU is 70-80% and is comparable with those of other leading TC forecasting centres in the world.

Keywords

Cone of Uncertainty, Forecast, Ocean Basin, Track, Tropical Cyclone.
User
Notifications
Font Size

  • Mohapatra, M., Mandal, G. S., Bandyopadhyay, B. K., Tyagi, A. and Mohanty, U. C., Classification of cyclone hazard prone districts of India. Nat. Hazards, 2012, 63, 1601–1620.
  • Mohapatra, M., Cyclone hazard proneness of districts of India. J. Earth Syst. Sci., 2015, 124, 515–526.
  • Mohapatra, M., Bandyopadhyay, B. K. and Tyagi, A., Construction and quality of best tracks parameters for study of climate change impact on tropical cyclones over the north Indian Ocean during satellite era. In Monitoring and Prediction of Tropical Cyclones over the Indian Ocean and Climate Change (ed. Mohanty U. C. et al.), Springer, The Netherlands and Capital Publishers, New Delhi, 2014, pp. 3–17.
  • Kotal, S. D. and Bhowmik, S. K. R., A multimodel ensemble technique for cyclone track prediction over north Indian Sea. Geofizika, 2011, 28, 275–291.
  • Mohapatra, M., Nayak, D. P., Sharma, R. P. and Bandyopadhyay, B. K., Evaluation of official tropical cyclone track forecast over north Indian Ocean issued by India Meteorological Department. J. Earth Syst. Sci., 2013, 122, 589–601.
  • Mohapatra, M., Nayak D. P. and Bandyopadhyay, B. K., Evaluation of cone of uncertainty in tropical cyclone track forecast over north Indian ocean issued by India Meteorological Department. Trop. Cyclone Res. Rev., 2012, 1, 331–339.
  • World Meteorological Organization, Eighth International Workshop on Tropical Cyclones (IWTC-VIII), Topic-1, Advances in forecasting TC motion, 2014; www.wmo.int/pages/prog/arep/wwrp/new/documents/Topic1_AdvancesinForecastingMotion.pdf
  • Dupont, T., Plu, M., Caroff, P. and Faure, G., Varification of ensemble-based uncertainty circles around tropical cyclone track forecasts. Weather Forecast., 2011, 26, 664–676.
  • Regional Specialised Meteorological Centre, New Delhi, A report on cyclonic disturbances over north Indian Ocean during 2014. India Meteorological Department, New Delhi, 2014.
  • IMD, Cyclone warning in India: standard operation procedure. India Meteorological Department, New Delhi, 2013, p. 172.
  • Mohapatra, M., Sikka, D. R., Bandyopadhyay, B. K. and Tyagi, A., Outcomes and Challenges of Forecast Demonstration Project (FDP) on landfalling cyclones over the Bay of Bengal. MAUSAM, 2013, 64, 1–12.

Abstract Views: 246

PDF Views: 73




  • Reduction in Uncertainty in Tropical Cyclone Track Forecasts over the North Indian Ocean

Abstract Views: 246  |  PDF Views: 73

Authors

M. Mohapatra
India Meteorological Department, Mausam Bhavan, Lodhi Road, New Delhi 110 003, India
B. Geetha
India Meteorological Department, Mausam Bhavan, Lodhi Road, New Delhi 110 003, India
Monica Sharma
India Meteorological Department, Mausam Bhavan, Lodhi Road, New Delhi 110 003, India

Abstract


Over the North Indian Ocean (NIO) basin, the uncertainty in tropical cyclone (TC) track forecast is depicted by constructing a cone of uncertainty (COU) around the forecast track for the benefit of disaster managers in their decision-making, especially with respect to area of evacuation. The COU is constructed by drawing a tangent to the circles with the radii equal to average track forecast errors during the past five years for forecast times of 12, 24, 36, …, up to 120 h. The COU which is revised periodically to reflect the track forecast accuracy, has been recently revised by India Meteorological Department (IMD) from the post-monsoon season of 2014. Hence, a study has been undertaken to evaluate this newly introduced COU forecast by IMD. The revised radii used to construct the COU have shrunk by 20-30% due to improved TC track forecast in the recent years (2009-2013). For the new COU, the radii of circles for 24, 48, 72, 96 and 120 h forecasts are 65, 105, 140, 170 and 200 nm respectively, against 80, 135, 185, 235 and 285 nm for the previous COU (2009-2013). The accuracy of the newly constructed forecast COU is 70-80% and is comparable with those of other leading TC forecasting centres in the world.

Keywords


Cone of Uncertainty, Forecast, Ocean Basin, Track, Tropical Cyclone.

References





DOI: https://doi.org/10.18520/cs%2Fv112%2Fi09%2F1826-1830