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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Victoria Heatwave January Heat waveCool change ACCESS-G E-Control E-Median days ahead 4 -7 days ahead

Victoria Heatwave January January Lead time ~ 9 days 15 January Lead time ~ 8 days 14 January Lead time ~ 7 days Probability T2m > 100 o F

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

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

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

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

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

Queensland & NSW flooding – ex-TC Oswald 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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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: Web: