Articles | Volume 12, issue 7
Geosci. Model Dev., 12, 3135–3148, 2019
Geosci. Model Dev., 12, 3135–3148, 2019

Development and technical paper 24 Jul 2019

Development and technical paper | 24 Jul 2019

How to use mixed precision in ocean models: exploring a potential reduction of numerical precision in NEMO 4.0 and ROMS 3.6

Oriol Tintó Prims et al.

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Revised manuscript accepted for GMD
Short summary

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Cited articles

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Baboulin, M., Buttari, A., Dongarra, J., Kurzak, J., Langou, J., Langou, J., Luszczek, P., and Tomov, S.: Accelerating scientific computations with mixed precision algorithms, Comput. Phys. Commun., 180, 2526–2533,, 2009. a, b, c
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Short summary
Mixed-precision approaches can provide substantial speed-ups for both computing- and memory-bound codes, requiring little effort. A novel method to enable modern and legacy codes to benefit from a reduction of precision without sacrificing accuracy is presented. Using a precision emulator and a divide-and-conquer algorithm it identifies the parts that cannot handle reduced precision and the ones that can. The method has been proved using two ocean models, NEMO and ROMS, with promising results.