Verifying the relationships among the variabilities of summer rainfall extremes over Japan in the d4PDF climate ensemble, Pacific sea surface temperature, and monsoon activity

Lee, Shao-Yi; He, Sicheng; Takemi, Tetsuya

doi:https://doi.org/10.5194/nhess-25-2225-2025

Articles | Volume 25, issue 7

https://doi.org/10.5194/nhess-25-2225-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/nhess-25-2225-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 25, issue 7

Research article

|

08 Jul 2025

Research article |

| 08 Jul 2025

Verifying the relationships among the variabilities of summer rainfall extremes over Japan in the d4PDF climate ensemble, Pacific sea surface temperature, and monsoon activity

Shao-Yi Lee, Sicheng He, and Tetsuya Takemi

Data sets

Global Sea Surface Temperature Data Sets Tokyo Climate Center https://ds.data.jma.go.jp/tcc/tcc/products/elnino/cobesst/cobe-sst.html

Past Meteorological Data Download Japan Meteorological Agency (JMA) https://www.data.jma.go.jp/gmd/risk/obsdl/index.php

Climate Indices: Monthly Atmospheric and Ocean time Series National Oceanic and Atmospheric Administration (NOAA) https://psl.noaa.gov/data/climateindices/list

Model code and software

CDO User Guide (2.1.0) Uwe Schulzweida https://doi.org/10.5281/zenodo.7112925

The NCAR Command Language NCL https://doi.org/10.5065/D6WD3XH5

The GNU Image Manipulation Program (GIMP), Version 2.10.14 GIMP https://www.gimp.org

Short summary

The authors performed verification on the relationships between extreme monsoon rainfall over Japan and Pacific sea surface temperature variability in the “database for Policy Decision-making for Future climate changes” (d4PDF). Observations showed widespread weak relationships between hourly extremes and the warming mode but reversed relationships between daily extremes and the decadal variability mode. Biases in d4PDF could be explained by the monsoon's slower movement over Japan in the model.