Quantifying overlapping and differing information of global precipitation for GCM forecasts and El Niño–Southern Oscillation

Abstract. While El Niño–Southern Oscillation (ENSO) teleconnection has long been used in statistical precipitation forecasting, global climate models (GCMs) provide increasingly available dynamical forecasts for hydrological modeling and water resources management. It is not yet known to what extent GCM new information compared teleconnection. This paper develops a novel set operations of coefficients determination (SOCD) method explicitly quantify the overlapping differing ENSO Specifically, intersection operation coefficient derives Niño3.4 index, then difference determines (Niño3.4 index) from index (GCM forecasts). A case study devised Climate Forecast System version 2 (CFSv2) seasonal December–January–February. The results show that significant 34.94 % land grid cells, 31.18 cells 11.37 cells. These confirm effectiveness GCMs capturing ENSO-related variability illustrate where there room improvement forecasts. Furthermore, bootstrapping significance tests three types facilitate total eight patterns disentangle close but divergent associations forecast correlation skill with