Reliable low precision simulations in land surface models
Weather and climate models must continue to increase in both resolution and complexity in order that forecasts become more accurate and reliable. Moving to lower numerical precision may be an essential tool for coping with the demand for ever increasing model complexity in addition to increasing com...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
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Springer Nature
2017
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| _version_ | 1797169923895590912 |
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| author | Dawson, A Düben, P Macleod, D Palmer, T |
| author_facet | Dawson, A Düben, P Macleod, D Palmer, T |
| author_sort | Dawson, A |
| collection | OXFORD |
| description | Weather and climate models must continue to increase in both resolution and complexity in order that forecasts become more accurate and reliable. Moving to lower numerical precision may be an essential tool for coping with the demand for ever increasing model complexity in addition to increasing computing resources. However, there have been some concerns in the weather and climate modelling community over the suitability of lower precision for climate models, particularly for representing processes that change very slowly over long time-scales. These processes are difficult to represent using low precision due to time increments being systematically rounded to zero. Idealised simulations are used to demonstrate that a model of deep soil heat diffusion that fails when run in single precision can be modified to work correctly using low precision, by splitting up the model into a small higher precision part and a low precision part. This strategy retains the computational benefits of reduced precision whilst preserving accuracy. This same technique is also applied to a full complexity land surface model, resulting in rounding errors that are significantly smaller than initial condition and parameter uncertainties. Although lower precision will present some problems for the weather and climate modelling community, many of the problems can likely be overcome using a straightforward and physically motivated application of reduced precision. |
| first_indexed | 2024-03-07T00:20:19Z |
| format | Journal article |
| id | oxford-uuid:7c524a82-70ef-4a89-a14d-bff05896ca5d |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T00:20:19Z |
| publishDate | 2017 |
| publisher | Springer Nature |
| record_format | dspace |
| spelling | oxford-uuid:7c524a82-70ef-4a89-a14d-bff05896ca5d2022-03-26T20:56:18ZReliable low precision simulations in land surface modelsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:7c524a82-70ef-4a89-a14d-bff05896ca5dEnglishSymplectic Elements at OxfordSpringer Nature2017Dawson, ADüben, PMacleod, DPalmer, TWeather and climate models must continue to increase in both resolution and complexity in order that forecasts become more accurate and reliable. Moving to lower numerical precision may be an essential tool for coping with the demand for ever increasing model complexity in addition to increasing computing resources. However, there have been some concerns in the weather and climate modelling community over the suitability of lower precision for climate models, particularly for representing processes that change very slowly over long time-scales. These processes are difficult to represent using low precision due to time increments being systematically rounded to zero. Idealised simulations are used to demonstrate that a model of deep soil heat diffusion that fails when run in single precision can be modified to work correctly using low precision, by splitting up the model into a small higher precision part and a low precision part. This strategy retains the computational benefits of reduced precision whilst preserving accuracy. This same technique is also applied to a full complexity land surface model, resulting in rounding errors that are significantly smaller than initial condition and parameter uncertainties. Although lower precision will present some problems for the weather and climate modelling community, many of the problems can likely be overcome using a straightforward and physically motivated application of reduced precision. |
| spellingShingle | Dawson, A Düben, P Macleod, D Palmer, T Reliable low precision simulations in land surface models |
| title | Reliable low precision simulations in land surface models |
| title_full | Reliable low precision simulations in land surface models |
| title_fullStr | Reliable low precision simulations in land surface models |
| title_full_unstemmed | Reliable low precision simulations in land surface models |
| title_short | Reliable low precision simulations in land surface models |
| title_sort | reliable low precision simulations in land surface models |
| work_keys_str_mv | AT dawsona reliablelowprecisionsimulationsinlandsurfacemodels AT dubenp reliablelowprecisionsimulationsinlandsurfacemodels AT macleodd reliablelowprecisionsimulationsinlandsurfacemodels AT palmert reliablelowprecisionsimulationsinlandsurfacemodels |