SINGV – the Convective-Scale Numerical Weather Prediction System for Singapore
pdf

Keywords

Convective-scale weather modelling
Atmospheric data assimilation
Ensemble forecasts
Numerical weather prediction systems
Deep tropics

Abstract

Extreme rainfall is one of the primary meteorological hazards in Singapore, as well as elsewhere in the deep tropics, and it can lead to significant local flooding. Since 2013, the Meteorological Service Singapore (MSS) and the United Kingdom Met Office (UKMO) have been collaborating to develop a convective-scale Numerical Weather Prediction (NWP) system, called SINGV. Its primary aim is to provide improved weather forecasts for Singapore and the surrounding region, with a focus on improved short-range prediction of localized heavy rainfall. This paper provides an overview of the SINGV development, the latest NWP capabilities at MSS and some key results of evaluation. The paper describes science advances relevant to the development of any km-scale NWP suitable for the deep tropics and provides some insights into the impact of local data assimilation and utility of ensemble predictions.

https://doi.org/10.29037/ajstd.581
pdf

References

Aranami K, Davies T, Wood N. 2015. A mass restoration scheme for limited-area models with semi-Lagrangian advection. Quart J Roy Meteor Soc. 141(690):1795–1803. doi:10.1002/qj.2482.

Ballard SP, Li Z, Simonin D, Caron JF. 2016. Performance of 4D-Var NWP-based nowcasting of precipitation at the Met Office for summer 2012: 4D-Var NWP-based Nowcasting of precipitation. Quart J Roy Meteor Soc. 142(694):472–487. doi:10.1002/qj.2665.

Bannister RN. 2017. A review of operational methods of variational and ensemble-variational data assimilation. Quart J Roy Meteor Soc. 143(703):607–633. doi:10.1002/qj.2982.

Best MJ, Pryor M, Clark DB, Rooney GG, Essery RLH, Ménard CB, Edwards JM, Hendry MA, Porson A, Gedney N, et al. 2011. The Joint UK Land Environment Simulator (JULES), model description – part 1: energy and water fluxes. Geosci Model Dev. 4(3):677–699. doi:10.5194/gmd-4-677-2011.

Bloom SC, Takacs LL, da Silva AM, Ledvina D. 1996. Data assimilation using incremental analysis updates. Mon Weather Rev. 124(6):1256–1271. doi:10.1175/1520-0493(1996)124<1256:DAUIAU> 2.0.CO;2.

Boutle IA, Eyre JEJ, Lock AP. 2014. Seamless stratocumulus simulation across the turbulent gray zone. Mon Weather Rev. 142(4):1655–1668. doi:10.1175/MWR-D-13-00229.1.

Bowler NE, Arribas A, Mylne KR, Robertson KB, Beare SE. 2008. The MOGREPS short-range ensemble prediction system. Quart J Roy Meteor Soc. 134(632):703–722. doi:10.1002/qj.234.

Brown A, Milton S, Cullen M, Golding B, Mitchell J, Shelly A. 2012. Unified modeling and prediction of weather and climate: a 25-year journey. Bull Amer Meteor Soc. 93(12):1865–1877. doi:10.1175/BAMS-D-12-00018.1.

Brown AR. 1999. The sensitivity of large-eddy simulations of shallow cumulus convection to resolution and subgrid model. Quart J Roy Meteor Soc. 125(554):469–482. doi:10.1002/qj.49712555405.

Bush M, Allen T, Bain C, Boutle I, Edwards J, Finnenkoetter A, Franklin C, Hanley K, Lean H, Lock A, et al. 2019. The first Met Office Unified Model/JULES Regional Atmosphere and Land configuration, RAL1. Geosci Model Dev Discuss, in review. doi:10.5194/gmd-2019-130.

Cameron J, Bell W. 2015. Pre-operational testing of variational bias correction (VarBC). Satellite Applications Technical Memo 37. Exeter: Met Office.

Clayton AM, Lorenc AC, Barker DM. 2013. Operational implementation of a hybrid ensemble/4D-Var global data assimilation system at the Met Office. Quart J Roy Meteor Soc. 139(675):1445–1461. doi:10.1002/qj.2054.

Donlon CJ, Martin M, Stark J, Roberts-Jones J, Fiedler E, Wimmer W. 2012. The Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) system. Remote Sens Environ. 116:140–158. doi:10.1016/j.rse.2010.10.017.

Edwards J, Slingo A. 1996. Studies with a flexible new radiation code. i: choosing a configuration for a large-scale model. Quart J Roy Meteor Soc. 122(531):689–719. doi:10.1002/qj.49712253107.

Gustafsson N, Janjić T, Schraff C, Leuenberger D, Weissmann M, Reich H, Brousseau P, Montmerle T, Wattrelot E, Bučánek A, et al. 2018. Survey of data assimilation methods for convective-scale numerical weather prediction at operational centres. Quart J Roy Meteor Soc. 144(713):1218–1256. doi:10.1002/qj.3179.

Hagelin S, Son J, Swinbank R, McCabe A, Roberts N, Tennant W. 2017. The Met Office convective-scale ensemble, MOGREPS-UK. Quart J Roy Meteor Soc. 143(708):2846–2861. doi:10.1002/qj.3135.

Heng BCP, Tubbs R, Huang XY, Macpherson B, Barker DM, Boyd DFA, Kelly G, North R, Stewart L, Webster S. 2020. SINGV-DA: A data assimilation system for convective-scale numerical weather prediction over Singapore. Quart J Roy Meteorol Soc, in review.

Hough MN, Jones RJA. 1997. The United Kingdom Meteorological Office rainfall and evaporation calculation system: MORECS version 2.0-an overview. Hydrol Earth Syst Sci. 1(2):227–239. doi:10.5194/hess-1-227-1997.

Ingleby NB. 2001. The statistical structure of forecast errors and its representation in the Met. Office Global 3-D Variational Data Assimilation Scheme. Quart J Roy Meteor Soc. 127(571):209–231. doi:10.1002/qj.49712757112.

Lilly DK. 1962. On the numerical simulation of buoyant convection. Tellus. 14(2):148–172. doi:10.3402/tellusa.v14i2.9537.

Lock AP, Brown AR, Bush MR, Martin GM, Smith RNB. 2000. A new boundary layer mixing scheme. Part I: scheme description and single-column model tests. Mon Weather Rev. 128(9):3187–3199. doi:10.1175/1520-0493(2000)128<3187:ANBLMS>2.0.CO;2.

Lorenc AC, Ballard SP, Bell RS, Ingleby NB, Andrews PLF, Barker DM, Bray JR, Clayton AM, Dalby T, Li D, Payne TJ, Saunders FW. 2000. The Met. Office global three-dimensional variational data assimilation scheme. Quart J Roy Meteor Soc. 126(570):2991–3012. doi:10.1002/qj.49712657002.

Molteni F, Buizza R, Palmer TN, Petroliagis T. 1996. The ECMWF Ensemble Prediction System: methodology and validation. Quart J Roy Meteor Soc. 122(529):73–119. doi:10.1002/qj.49712252905.

Morcrette CJ. 2012a. Improvements to a prognostic cloud scheme through changes to its cloud erosion parametrization. Atmos Sci Lett. 13(2):95–102. doi:10.1002/asl.374.

Morcrette CJ. 2012b. Prognostic-cloud-scheme increment diagnostics: a novel addition to the case-study tool kit. Atmos Sci Lett. 13(3):200–207. doi:10.1002/asl.380.

Porson AN, Hagelin S, Boyd DFA, Roberts NM, North R, Webster S, Lo JCF. 2019. Extreme rainfall sensitivity in convective-scale ensemble modelling over Singapore. Quart J Roy Meteorol Soc. 145:3004–3022. doi:10.1002/qj.3601.

Rawlins F, Ballard SP, Bovis KJ, Clayton AM, Li D, Inverarity GW, Lorenc AC, Payne TJ. 2007. The Met Office global four-dimensional variational data assimilation scheme. Quart J Roy Meteor Soc. 133(623):347–362. doi:10.1002/qj.32.

Renshaw R, Francis PN. 2011. Variational assimilation of cloud fraction in the operational Met Office Unified Model. Quart J Roy Meteorol Soc. 137:1963–1974. doi:10.1002/qj.980.

Roberts NM, Lean HW. 2008. Scale-selective verification of rainfall accumulations from high-resolution forecasts of convective events. Mon Weather Rev. 136(1):78–97. doi:10.1175/2007MWR2123.1.

Simón-Moral A, Dipankar A, Roth M, Sánchez C, Velasco E, Huang XY. 2019. Application of a single layer urban canopy model in a tropical city: preliminary results from Singapore. Quart J Roy Meteorol Soc. doi:10.1002/qj.3694.

Skamarock WC, Klemp JB, Dudhia J, Gill DO, Barker DM, Duda M, Huang XY, Wang W, Powers JG. 2008. A description of the advanced research WRF version 3. Technical report. UCAR/NCAR. doi:10.5065/D68S4MVH.

Skofronick-Jackson G, Petersen WA, Berg W, Kidd C, Stocker EF, Kirschbaum DB, Kakar R, Braun SA, Huffman GJ, Iguchi T, et al. 2017. The Global Precipitation Measurement (GPM) mission for science and society. Bull Amer Meteor Soc. 98(8):1679–1695. doi:10.1175/BAMS-D-15-00306.1.

Smith RNB. 1990. A scheme for predicting layer clouds and their water content in a general circulation model. Quart J Roy Meteor Soc. 116(492):435–460. doi:10.1002/qj.49711649210.

Sun X, Huang XY, Gordon C, Mittermaier M, Beckett R, Cheong WK, Barker DM, North R, Semple A. 2020. A subjective and objective evaluation of model forecasts of Sumatra squall events. Weather and Forecasting, in review.

Tang Y, Lean HW, Bornemann J. 2013. The benefits of the Met Office variable resolution NWP model for forecasting convection: variable resolution NWP for forecasting convection. Meteorol Appl. 20(4):417–426. doi:10.1002/met.1300.

Thompson B, Sanchez C, Sun X, Song G, Liu J, Huang XY, Tkalich P. 2019. A high-resolution atmosphere–ocean coupled model for the western Maritime Continent: development and preliminary assessment. Climate Dyn. 52(7-8):3951–3981. doi:10.1007/s00382-018-4367-0.

Timbal B, Venkatraman P, Hassim M. 2019. SINGV as a Regional Climate Model to deliver Singapore’s 3rd National Climate Change Study. MSS Res Lett. 2(4):3–13.

Walters D, Baran AJ, Boutle I, Brooks M, Earnshaw P, Edwards J, Furtado K, Hill P, Lock A, Manners J, et al. 2019. The Met Office Unified Model Global Atmosphere 7.0/7.1 and JULES Global Land 7.0 configurations. Geosci Model Dev. 12(5):1909–1963. doi:10.5194/gmd-12-1909-2019.

Webster S, Dipankar A, Furtado K, Wilkinson J, Sanchez C, Lock A, North R, Sun X, Vosper S, Huang XY, Barker DM. 2020. SINGV: a convective-scale weather forecast model for Singapore. Quart J Roy Meteorol Soc, to be submitted.

Wilson DR, Ballard SP. 1999. A microphysically based precipitation scheme for the UK Meteorological Office Unified Model. Quart J Roy Meteor Soc. 125(557):1607–1636. doi:10.1256/smsqj.55706.

Wilson DR, Bushell AC, Kerr-Munslow AM, Price JD, Morcrette CJ. 2008. PC2: a prognostic cloud fraction and condensation scheme. I: scheme description. Quart J Roy Meteor Soc. 134(637):2093–2107. doi:10.1002/qj.333.

Wood N, Staniforth A, White A, Allen T, Diamantakis M, Gross M, Melvin T, Smith C, Vosper S, Zerroukat M, Thuburn J. 2014. An inherently mass-conserving semi-implicit semi-Lagrangian discretization of the deep-atmosphere global non-hydrostatic equations. Quart J Roy Meteor Soc. 140(682):1505–1520. doi:10.1002/qj.2235.

Zerroukat M. 2010. A simple mass conserving semi-Lagrangian scheme for transport problems. J Comput Phys. 229(24):9011–9019. doi:10.1016/j.jcp.2010.08.017.

Zerroukat M, Shipway BJ. 2017. ZLF (Zero Lateral Flux): a simple mass conservation method for semi-Lagrangian-based limited-area models: conservation in Limited Area Models. Quart J Roy Meteor Soc. 143(707):2578–2584. doi:10.1002/qj.3108.

Žagar N, Isaksen L, Tan D, Tribbia J. 2013. Balance properties of the short-range forecast errors in the ECMWF 4D-Var ensemble. Quart J Roy Meteor Soc. 139(674):1229–1238. doi:10.1002/qj.2033.

Downloads

Download data is not yet available.