Subseasonal Forecasts of the 2018 Indian Summer Monsoon Over Bihar

Andrew W. Robertson, Nachiketa Acharya, Lisa Goddard, D. R. Pattanaik, A. K. Sahai, K. K. Singh, Kripan Ghosh, Anshul Agarwal, James L. Buizer

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

Calibrated probabilistic forecasts of weekly rainfall were developed for the state of Bihar in northern India and issued in real time during the June–September 2018 monsoon period, up to 2 weeks in advance. The forecasts are based on subseasonal forecasts from the U.S. National Centers for Environmental Prediction CFSv2 model and were calibrated against observed gridded rainfall fields from the India Meteorological Department using canonical correlation analysis. Hindcasts over the 1999–2010 period exhibit appreciable skill at Week 1 lead (Days 3–9), with some skill at Week 2 (Days 10–16), over Bihar as well as over a larger region. Forecasts were issued in real time during the 2018 Indian summer monsoon season for four districts in Bihar on a 1° grid in tercile probability format every Thursday. Verification of the district-level real-time forecasts over the 2018 season is evaluated and moderate skill demonstrated in terms of the Brier and Heidke skill scores, especially for the northern districts and for the below-normal category. Successful monsoon onset and break phase forecasts in 2018 over Bihar are related to episodes of the Madden-Julian Oscillation, which the model is shown to capture quite well at 1–2 week lead.

Original languageEnglish (US)
Pages (from-to)13861-13875
Number of pages15
JournalJournal of Geophysical Research: Atmospheres
Volume124
Issue number24
DOIs
StatePublished - Dec 27 2019

ASJC Scopus subject areas

  • Geophysics
  • Forestry
  • Oceanography
  • Aquatic Science
  • Ecology
  • Water Science and Technology
  • Soil Science
  • Geochemistry and Petrology
  • Earth-Surface Processes
  • Atmospheric Science
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science
  • Palaeontology

Fingerprint Dive into the research topics of 'Subseasonal Forecasts of the 2018 Indian Summer Monsoon Over Bihar'. Together they form a unique fingerprint.

Cite this