This is a Preprint and has not been peer reviewed. The published version of this Preprint is available: https://doi.org/10.1007/s13351-020-0049-z. This is version 1 of this Preprint.
You must log in to post a comment.
Rainfall forecasts for the summer monsoon season in the Yangtze River Basin allow decision-makers to plan for possible flooding, which can affect the lives and livelihoods of millions of people.
A trial climate service was developed in 2016, producing a prototype seasonal forecast product for use by stakeholders in the region, based on forecasting rainfall directly using a dynamical model. Here we describe an improved service, based on a simple statistical downscaling approach: using a dynamical forecast of an East Asian Summer Monsoon index, seasonal-mean rainfall for the Upper and Middle/Lower Reaches of the basin can be forecast separately, with significant skill for lead times of up to at least 3 months. The skill in the different sub-basin regions depends on the target season: Rainfall skill in the Middle/Lower Reaches is significant in May–June–July (MJJ), and there is significant skill for the Upper Reaches in June–July–August (JJA). The mean rainfall for the basin as a whole can be skillfully forecast in both seasons. The forecasts issued in 2019 gave good guidance for the enhanced rainfall in the MJJ period, and the near-average conditions in JJA. Initial feedback from users in the Yangtze River Basin suggests that the improved forecast better meets their needs and will enable more robust decision-making.
Atmospheric Sciences, Climate, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
East Asian Summer Monsoon, flood forecasting, seasonal forecasting, Yangtze basin rainfall
Published: 2020-03-18 15:48