1. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology ACCESS Global Ensemble Prediction System Michael Naughton David Smith Asri Sulaiman Earth System Modelling Program Bureau of Meteorology CSIRO Computational and Simulation Sciences and eResearch Conference, 12 February 2015

2. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

3. ACCESS-GE epsgrams from this morning's run The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Rainfall Temperature Wind Cloud

4. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

5. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Motivation for Ensemble Prediction NWP forecasts contain uncertainties Internal and external users can make better decisions when uncertainty information is provided Ensemble prediction is a good way to estimate forecast uncertainty

6. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Service requirements for probability forecasts Fire weather warnings – probability of high fire danger conditions; timing, and intensity of wind changes Thunderstorms – probability of conditions favourable for severe weather Heat wave warnings – probability of exceeding critical heat stress index based on temperature, humidity, and wind speed Precipitation – probabilities of exceeding critical accumulation thresholds Wind – probability of gales – crucial for tropical regions Waves – probabilities of exceeding critical wave heights Tropical cyclones – strike probability

7. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology NWP Ensemble Prediction methodologies Multi-model ensemble (Poor Man’s Ensemble) – form ensemble from deterministic forecasts from available local and overseas models Single-centre EPS systems – form ensemble of multiple runs of forecast model with different initial conditions and different model settings Multi-EPS systems – form ensemble from ensemble forecasts from multiple centres Time-lagged ensembles – form ensemble from consecutive runs Statistical ensembles – form ensemble using statistical downscaling techniques applied to single model forecast or ensemble of forecasts

8. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

9. ACCESS-GE global ensemble prediction system Currently running 12Z daily at 60 km, 70 levels (N216L70) Planned for operational implementation in 2H 2015 (APS2) 24-member ensemble designed for medium-range forecasting Based on UKMO MOGREPS Global ensemble to 10 days Global ETKF for initial condition perts Stochastic model perturbations ACCESS-G 40km (N320) – G2 25km (N512) ACCESS-GE 60km (N216) ACCESS-R 12 km ACCESS-C C1: 4km C2: 1.5km

10. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

11. ACCESS-GE - Verification Against Analysis January 2015 The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology` MSLPT850 Aust NH Trop SH ACCESS-G E-Control E-Mean E-Spread Ensemble mean skill better than deterministic ACCESS-G after first couple/few days

12. Verification – Spread-skill c.f. other centres ACCESS-GE ECMWF JMA NCEP MSLP December 2014 SHEM TROP NHEM

13. Verification – Spread-skill c.f. other centres ACCESS-GE ECMWF JMA NCEP T850 December 2014 SHEM TROP NHEM

14. Verification – Spread-skill c.f. other centres ACCESS-GE ECMWF JMA U850 December 2014 SHEM TROP NHEM

15. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

16. Victoria Heatwave January 13-16 2014 Heat waveCool change ACCESS-G E-Control E-Median 13 141516 13 141516 17 18 19 7-10 days ahead 4 -7 days ahead

17. Victoria Heatwave January 13-16 2014 16 January Lead time ~ 9 days 15 January Lead time ~ 8 days 14 January Lead time ~ 7 days Probability T2m > 100 o F

18. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

19. Warrimoo Bushfire (near Katoomba, Blue Mountains, NSW) Friday, 14 Nov 2014

20. ACCESS-GE demonstration products provided to NSW RFS High fire danger for 14 Nov 2014 forecast 4 days ahead High temperature, strong westerly wind, low humidity

21. Forecast uncertainty in the change position ECMWF EPS 24-hour forecast Valid 11 pm EDT Black Saturday 7 February 2009 Shading: NW component of temperature gradient (max = front position) Arrows: Temperature gradient Grey lines: front position in ensemble members White line: front position in control forecast Numbers: standard deviation of front position (degrees longitude) Courtesy Jeff Kepert

22. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

23. Queensland & NSW flooding – ex-TC Oswald 22-29 Jan 2013 This event followed the monsoon onset in mid- January. TC Oswald formed in the western part of Gulf of Carpentaria around 20 January. It existed briefly as TC until it made landfall and moved across the Cape York peninsula as a tropical low. Ex-TC Oswald then progressed over the following week down the Queensland coast and through to the northern NSW as far as the Sydney region, before moving off to the east on 29 January.

24. Queensland & NSW flooding – ex-TC Oswald 22-29 Jan 2013 Floodwaters cover the central Queensland city of Bundaberg in the wake of ex-tropical cyclone Oswald, January 29, 2013. ABC: Audience submitted: John McDermott abc.net.au/news/2013-01- 27/queensland-floods-as-oswald- moves-south/4486174

25. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

26. TC Ita April 2014 The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Probability that TC ITA will be within 120km after 72h IC:12Z 10 AprilIC:12Z 11 April

27. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

28. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology The Australian National Thunderstorm Forecast Guidance System (NTFGS): Calibrated ensemble-based total thunderstorm probabilities Harald Richter Centre for Australian Weather and Climate Research, Melbourne, Australia www.cawcr.gov.au

29. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Calibrated Thunderstorm Probabilities from NWP Courtesy Harald Richter

30. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Calibrated Thunderstorm Probabilities from NWP Courtesy Harald Richter

31. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Calibrated Thunderstorm Probabilities from 1.5 km RUC Courtesy Harald Richter

32. Outline Today's EPSgram Rationale of ensemble prediction Description of ACCESS-GE system ACCESS-GE verifications Examples and applications Jan 2014 heatwave Fire weather example products Ex-TC Oswald Jan 2013 Queensland flooding TC strike probability Calibrated Thunder – thunderstorm forecast system Volcanic ash transport Seamless rainfall forecasting Summary

33. Volcanic ash dispersion from eruption of Kelut, Java, Indonesia, 13 February 2014 Courtesy Richard Dare

34. Volcanic ash dispersion from eruption of Kelut, Indonesia, 13 February 2014 Courtesy Richard Dare

35. Volcanic ash dispersion from eruption of Kelut, Indonesia, 13 February 2014 Courtesy Richard Dare

36. Volcanic ash dispersion from eruption of Kelut, Indonesia, 13 February 2014 Individual member 24-hour forecasts of concentration in the 10-15 km layer Values above 10 -16 g m -3 red, otherwise blue Courtesy Richard Dare 24-hour forecasts of aviation hazard Single control member vs ensemble probability

37. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Summary Ensemble approaches are a core part of modern NWP and forecasting ACCESS-GE is the ACCESS global NWP ensemble system based on the UKMO MOGREPS operational ensemble system ACCESS-GE is running routinely in research mode, with probabilistic forecast products available daily in near-real-time ACCESS-GE system delivers comparable performance to overseas operational EPS systems ACCESS-GE system is planned to become operational in the 2015 APS2 upgrade to the ACCESS NWP operational system

38. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology Michael Naughton Phone: +61-3-9669-4411 Email: m.naughton@bom.gov.au Web: www.cawcr.gov.au www.cawcr.gov.au