Articles | Volume 19, issue 11
https://doi.org/10.5194/gmd-19-4817-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-19-4817-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Model evaluation paper
| 
05 Jun 2026
Model evaluation paper |
| 05 Jun 2026
| 05 Jun 2026
Why does the signal-to-noise paradox exist in seasonal climate predictability?
Shivamurthy Yashas
Indian Institute of Tropical Meteorology, Pune, India
Savitribai Phule Pune University, Pune, India
Indian Institute of Tropical Meteorology, Pune, India
Samir Pokhrel
Indian Institute of Tropical Meteorology, Pune, India
Mahen Konwar
Indian Institute of Tropical Meteorology, Pune, India
Verma Utkarsh
Indian Institute of Tropical Meteorology, Pune, India
Savitribai Phule Pune University, Pune, India
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Short summary
This study highlights challenges in estimating seasonal climate predictability using the
perfect modelframework, which assumes only initial conditions cause error. We show that forecasts can exceed the predicted limit, known as the Potential Predictability Limit (PPL), due to model imperfections in simulating physical processes. A new method is proposed to estimate PPL more accurately and avoid such paradoxes.
This study highlights challenges in estimating seasonal climate predictability using the
perfect...
