SPEAR: Seamless System for Prediction and EArth System Research
SPEAR was developed as a next generation GFDL modeling system for seasonal to multidecadal prediction and projection. In February 2021, SPEAR real-time seasonal predictions were made available as part of the North American Multi-Model Ensemble (NMME) and SPEAR decadal predictions will be made available as part of an international decadal prediction program through the UK Met Office (decadal forecast). Additional data from the SPEAR large ensemble, described in Delworth et al. (2020) will also be made available through the GFDL Data Portal in March 2021 (note: subset data from published papers to date is available at publication with details in each paper). Previously, the GFDL CM2.1 and FLOR models were used for real-time seasonal-to-decadal prediction and research.
The SPEAR models share many components with the recently developed GFDL CM4 (Held et al., 2019) model but with configuration and physical parameterization choices in SPEAR geared toward physical climate prediction and projection on seasonal to decadal (S2D) time scales. Present configurations of SPEAR contain the following characteristics:
| Configuration | Use | Atmosphere | Land | Ocean | Sea Ice |
|---|---|---|---|---|---|
| SPEAR_LO | Seasonal to decadal (S2D) research; decadal predictions to be delivered to international program through UK MetOffice starting in 2021 | AM4.0, (1°) 33 levels (Zhao et al. 2018a; Zhao et al. 2018b) | LM4.0, (1°), dynamic vegetation (Zhao et al. 2018a; Zhao et al. 2018b; Milly et al. 2014) | MOM6, (1°), tropical refinement to (0.3°), 75 levels, hybrid vertical coordinate | SIS2 sea ice (Adcroft et al., 2019) |
| SPEAR_MED | S2D research; seasonal predictions to be delivered to NMME and shared with various seasonal partners (e.g. NCEP) starting in 2021 | AM4.0, (0.5°) 33 levels (Zhao et al. 2018a; Zhao et al. 2018b) Zhao et al. 2018a; Zhao et al. 22018b | LM4.0, (0.5°), dynamic vegetation (Zhao et al. 2018a; Zhao et al. 2018b; Milly et al. 2014) | MOM6, (1°), tropical refinement to (0.3°), 75 levels, hybrid vertical coordinate | SIS2 sea ice (Adcroft et al., 2019) |
| SPEAR_HI | S2D research | AM4.0, (0.25°) 33 levels (Zhao et al. 2018a; Zhao et al. 2018b) | LM4.0, (0.25°), dynamic vegetation (Zhao et al. 2018a; Zhao et al. 2018b; Milly et al. 2014) | MOM6, (1°), tropical refinement to (0.3°), 75 levels, hybrid vertical coordinate | SIS2 sea ice (Adcroft et al., 2019) |
Note: horizontal resolution provided in parentheses.
References Describing SPEAR:
- Delworth, T. L., et al. (2020). SPEAR: The Next Generation GFDL Modeling System for Seasonal to Multidecadal Prediction and Projection. Journal of Advances in Modeling Earth Systems, 12(3), e2019MS001895.
- Lu, F., et al. (2020). GFDL’s SPEAR seasonal prediction system: initialization and ocean tendency adjustment (OTA) for coupled model predictions. Journal of Advances in Modeling Earth Systems, doi:10.1029/2020MS002149.
References using SPEAR data:
- Murakami, H., Delworth, T. L., Cooke, W. F., Zhao, M., Xiang, B., & Hsu, P. C. (2020). Detected climatic change in global distribution of tropical cyclones. Proceedings of the National Academy of Sciences, 117(20), 10706-10714. [GFDL Highlight]
- Zhang, L., & Cooke, W. (2020). Simulated changes of the Southern Ocean air-sea heat flux feedback in a warmer climate. Climate Dynamics, 1-16.
- Pascale, S., Kapnick, S.B., Delworth, T.L., Cooke, W.F., (2020). Increasing risk of another Cape Town “Day Zero” drought in the 21st century. Proceedings of the National Academy of Sciences, 117 (47) 29495-29503. [GFDL Highlight]
References Describing SPEAR Components / GFDL Model Development:
- Adcroft, A., et al. (2019). The GFDL global ocean and sea ice model 4.0: Model description and simulation features. Journal of Advances in Modeling Earth Systems, 11(10),3167-3211.
- Held, I. M., et al. (2019). Structure and performance of GFDL’s CM4.0 climate model. Journal of Advances in Modeling Earth Systems, 11(11), 3691-3727.
- Milly, P. C., et al. (2014). An enhanced model of land water and energy for global hydrologic and earth-system studies. Journal of Hydrometeorology, 15(5), 1739-1761.
- Zhao, M., et al. (2018a). The GFDL global atmosphere and land model AM4. 0/LM4. 0: 1. Simulation characteristics with prescribed SSTs. Journal of Advances in Modeling Earth Systems, 10(3), 691-734.
- Zhao, M., et al. (2018b). The GFDL global atmosphere and land model AM4. 0/LM4. 0: 2. Model description, sensitivity studies, and tuning strategies. Journal of Advances in Modeling Earth Systems, 10(3), 735-769.