NOCN03 CWAO 281719 GENOT ADMIN NO. 006 LA VERSION FRANCAISE DE CE GENOT EST LE NO. 007 THE FRENCH VERSION OF THIS GENOT IS NO. 007 MAJOR UPGRADE OF THE GLOBAL DETERMINISTIC PREDICTION SYSTEM (GDPS) OF THE METEOROLOGICAL SERVICE OF CANADA (MSC) ON JULY 3, 2019, STARTING WITH THE 1200 UTC RUN, THE CANADIAN METEOROLOGICAL CENTRE (CMC) OF THE MSC WILL IMPLEMENT VERSION 7.0.0 OF ITS GDPS, HEREAFTER REFERRED TO AS GDPS-7.0.0. THE MAIN CHANGE COMPARED TO THE PREVIOUS OPERATIONAL GDPS (VERSION 6.1.0) IS THE CHANGE FROM VERSION 4.8-LTS.16 OF THE GEM ATMOSPHERIC MODEL TO VERSION 5.0.0. THIS VERSION OF GEM COMES WITH MAJOR CHANGES TO THE PHYSICS PACKAGE, AS WELL AS SOME CHANGES TO THE DYNAMICS. IN ADDITION, THE GDPS-7.0.0 FEATURES A RESOLUTION INCREASE IN BOTH VERTICAL AND HORIZONTAL DIRECTIONS. THE SEA ICE AND SEA SURFACE TEMPERATURE (SST) ANALYSES HAVE ALSO BEEN SIGNIFICANTLY IMPROVED. BESIDE, SOME MINOR CHANGES TO THE ATMOSPHERIC DATA ASSIMILATION SYSTEM WERE ALSO INCLUDED. FINALLY, THERE WERE ALSO SOME CHANGES TO THE GEOPHYSICAL FIELDS AND TO THE OCEAN-ICE COMPONENT. IMPROVEMENTS (SOME OF WHICH ARE LARGE) ARE SEEN IN MOST UPPER-AIR AND SURFACE SCORES. THE CHANGES TO THE GDPS ARE OUTLINED BELOW. 1. CHANGES TO THE DATA ASSIMILATION COMPONENT 1.1 CHANGES IN ATMOSPHERIC DATA ASSIMILATION THE FOLLOWING CHANGES TO THE ATMOSPHERIC DATA ASSIMILATION ARE SUMMARIZED HERE: - CUTOFF TIME FOR OBSERVATIONS IN THE MAIN CONTINUOUS ASSIMILATION CYCLE COMPONENT OF THE GDPS SET TO 7 HOURS AFTER THE ANALYSIS VALIDITY TIME. THE SAME CUTOFF IS NOW USED AT ALL FOUR SYNOPTIC TIMES. - CORRECTION OF RADIOSONDE DATA DOUBLE COUNTING (TAC AND BUFR). - IMPROVE BIAS CORRECTION OF IASI AND AIRS USING SAME METHOD AS FOR CRIS. - TRANSFORMATION OF CONTROL VARIABLE FOR MOISTURE NOW DONE AT GRID POINTS INSTEAD OF AT OBSERVATION POINTS. 1.2 CHANGES IN SEA ICE AND SEA SURFACE TEMPERATURE ANALYSIS (SST) THE SEA ICE CONCENTRATION GLOBAL ANALYSIS HAS BEEN UPDATED BY ADDING TWO ADDITIONAL SATELLITE DATASETS, REGIONAL ICE CHARTS, A NEW CLIMATOLOGY FOR LAKES AND A NEW METHOD FOR FILTERING MICROWAVE OBSERVATIONS. THE NEW SST HAS A HIGHER RESOLUTION OF 0.10 DEGREES, USES TWO ADDITIONAL SATELLITE DATASETS, A NEW CLIMATOLOGY OBTAINED FROM A 20- YEAR REANALYSIS AND ALSO INCLUDES A NEW BACKGROUND ERROR CORRELATION MATRIX AND MODIFICATIONS TO CAPTURE SUDDEN SST CHANGES DUE TO TROPICAL STORMS. 2. CHANGES TO THE MODEL COMPONENT OF THE GDPS 2.1 CHANGE OF MODEL GRID GDPS-7.0.0 FEATURES A RESOLUTION INCREASE OF ITS ATMOSPHERIC MODEL IN BOTH VERTICAL AND HORIZONTAL DIRECTIONS. IN THE HORIZONTAL, A YIN-YANG GRID IS USED WITH A RESOLUTION GOING FROM 25 KM IN THE GDPS-6.1.0 TO 15 KM IN THE GDPS-7.0.0. IN THE VERTICAL, THE GDPS- 7.0.0 NOW FEATURES 84 LEVELS (INSTEAD OF 80) WITH THE FIRST THERMODYNAMIC LEVEL LOCATED AT 10 M ABOVE GROUND LEVEL (INSTEAD OF 20 M) IMPLYING A HIGHER RESOLUTION IN THE LOWER TROPOSPHERE. 2.2 CHANGE TO THE ATMOSPHERIC MODEL GDPS-7.0.0 USES THE ATMOSPHERIC MODEL GEM VERSION 5.0.0. THE MOST SIGNIFICANT CHANGES IN THIS VERSION OF GEM ARE RELATED TO THE PHYSICAL PACKAGE, WHICH UNDERWENT A MAJOR UPGRADE. MOST PHYSICAL PARAMETRIZATIONS HAVE BEEN REVISITED IN AN EFFORT TOWARDS THE 'UNIFICATION OF THE MODEL PHYSICS' AT THE CMC. INDEED, EXCEPT FOR A FEW RESOLUTION-DEPENDENT PARAMETERS, THE ATMOSPHERIC MODELS OF THE GDPS-7.0.0 AND THE VERSION 7.0.0 OF THE REGIONAL DETERMINISTIC PREDICTION SYSTEM (RDPS-7.0.0, IMPLEMENTED AT THE SAME TIME AS THE GDPS-7.0.0) SHARE THE SAME SET OF PHYSICAL PARAMETRIZATIONS AS WELL AS THE SAME DYNAMICAL-CORE CONFIGURATION. FOR INSTANCE, THE HORIZONTAL-DIFFUSION OPERATOR FOR MOMENTUM AND THE FORMULATION FOR THERMAL ROUGHNESS LENGTH OVER WATER ARE NOW THE SAME AS THOSE USED IN A PREVIOUS RDPS IMPLEMENTATION. IN ADDITION, THE BOUNDARY LAYER SCHEME OF THE GDPS WAS UPGRADED TOWARDS THE ONE THAT HAS BEEN USED BY HIGH-RESOLUTION SYSTEMS FOR MANY YEARS AT THE CMC, ALBEIT THE UNIFIED SCHEME INCLUDES SOME CHANGES (E.G. A NEW MIXING-LENGTH FORMULATION AS WELL AS A REVISED TREATMENT OF BOUNDARY LAYER CLOUDS) THAT ARE NOVEL TO BOTH THE GDPS AND RDPS SYSTEMS. THE LAND SURFACE SCHEME (ISBA) REMAINS THE SAME FOR THIS UPGRADE. THE CHANGES IN THE DYNAMICS OF GEM IN THE GDPS-7.0.0 ARE: MODIFIED HORIZONTAL DIFFUSION OPERATOR AND COEFFICIENT FOR MOMENTUM: ADJUSTED COEFFICIENT FOR DEL-2 DIFFUSION NEAR MODEL LID. AT THE LOWER BOUNDARY OF THE MODEL, THE TOPOGRAPHY IS LESS FILTERED IN THE NEW GDPS, INCREASING ITS EFFECTIVE RESOLUTION. MORE INFORMATION ABOUT THE CHANGES TO THE GEM MODEL CAN BE FOUND SOON IN THE TECHNICAL NOTE AT: HTTP://COLLABORATION.CMC.EC.GC.CA/CMC/CMOI/PRODUCT_GUIDE/DOCS/CHANGE S_E.HTML (LINK MUST BE TYPED ON A SINGLE LINE IN LOWERCASE) 2.3 CHANGES TO THE ICE-OCEAN MODEL THE SEA-ICE MODEL (CICE V4) IS UNCHANGED. THE OCEAN MODEL WAS UPDATED TO NEMO V3.6. HOWEVER, IN GENERAL, THE OCEAN PHYSICS AND PARAMETERS REMAIN THE SAME. THE ICE AND OCEAN INITIAL CONDITIONS WERE UPDATED AS THEY ARE NOW PRODUCED IN GLOBAL ICE AND OCEAN PREDICTION SYSTEM (GIOPS) VERSION 3.0.0. THE LATTER WAS UPDATED TO THE LATEST SAM AND NEMO CODE, AND A NEW BIAS CORRECTION METHOD WAS INTRODUCED. PLEASE REFER TO THE TECHNICAL NOTE OF GIOPS V3.0.0 FOR MORE DETAILS. HTTP://COLLABORATION.CMC.EC.GC.CA/CMC/CMOI/PRODUCT_GUIDE/DOCS/CHANGE S_E.HTML (LINK MUST BE TYPED ON A SINGLE LINE IN LOWERCASE) 3. PERFORMANCE EVALUATION THE PERFORMANCE OF THE NEW SYSTEM WAS EVALUATED BASED ON RESEARCH AND DEVELOPMENT (R AND D) EXPERIMENTS CARRIED OUT FOR PERIODS OF TWO MONTHS UNDER SUMMER AND WINTER CONDITIONS, AS WELL AS A SUBSEQUENT PARALLEL RUN DURING SPRING 2019. 3.1 IMPACT OF THE ATMOSPHERIC ASSIMILATION COMPONENT CHANGES CHANGES TO THE ATMOSPHERIC DATA ASSIMILATION COMPONENT HAD NO SIGNIFICANT IMPACTS. 3.2 OBJECTIVE EVALUATION OF THE ATMOSPHERIC FORECAST COMPONENT OBJECTIVE SCORES AGAINST RADIOSONDES AS WELL AS INDEPENDENT REANALYSIS SHOW A SIGNIFICANT IMPROVEMENT IN THE STANDARD DEVIATION OF THE ERROR FOR ALL UPPER AIR VARIABLES (TEMPERATURE, MOISTURE, WIND AND GEOPOTENTIAL HEIGHT). THE SCORES ARE IMPROVED THROUGHOUT THE FORECAST LEAD TIMES BUT MORE NOTABLY FOR THE FIRST 120 HOURS WITH A REDUCTION OF 5 TO 10 PERCENT OF THE ROOT MEAN SQUARE ERROR (RMSE). THE NUMBER AND THE INTENSITY OF LARGE RMSE IN THE GEOPOTENTIAL HEIGHT AT VARIOUS PRESSURE LEVELS ARE ALSO SIGNIFICANTLY REDUCED. THE SAME CONCLUSION APPLIES TO THE SURFACE VARIABLES. THE BIASES ARE ALSO GENERALLY IMPROVED EXCEPT FOR THESE FOUR FOLLOWING POINTS: - INCREASED NEGATIVE BIASES IN TROPOSPHERIC WIND SPEEDS. - INCREASED POSITIVE TEMPERATURE BIAS CLOSE TO THE STRATOPAUSE. - INCREASED NEGATIVE TEMPERATURE BIAS IN THE CONTINENTAL BOUNDARY LAYER AND SURFACE DURING THE WINTER SEASON. - INCREASED POSITIVE TEMPERATURE BIAS IN THE TROPICAL BOUNDARY LAYER. FOR PRECIPITATION, THE FREQUENCY BIAS INDEX IS IMPROVED OVER NORTH AMERICA (WITH A GENERAL REDUCTION IN THE POSITIVE BIAS) EXCEPT NEUTRAL IN SUMMER OVER CANADA. THE PRECIPITATION THREAT SCORES ARE IMPROVED OVER NORTH AMERICA FOR BOTH SEASONS EXCEPT NEUTRAL IN WINTER OVER CANADA. OBJECTIVE EVALUATION OF TROPICAL CYCLONE (TC) FORECASTS SHOWED IMPROVEMENTS IN TC TRACKS, FREQUENCY AND THREAT SCORES IN GDPS-7.0.0 WHEN COMPARED TO GDPS-6.1.0. THESE IMPROVEMENTS ARE ATTRIBUTED TO THE MAJOR CHANGES IN THE PHYSICAL PARAMETRIZATIONS OF THE ATMOSPHERIC MODEL, IN PARTICULAR THE IMPROVED PARAMETRIZATION OF CONVECTIVE MOMENTUM TRANSFER IN THE DEEP CONVECTION SCHEME. FINALLY, OBJECTIVE SCORES OBTAINED FOR THE PARALLEL RUN DURING SPRING 2019 CLEARLY CONFIRM THE CONCLUSION OF THE PERFORMANCE EVALUATION OF THE R AND D PHASE FOR BOTH UPPER AIR AND SURFACE EVALUATIONS, ALTHOUGH THE IMPROVEMENT IS NOT AS IMPORTANT. INDEED, SPRING BEING A TRANSITION SEASON, EVALUATION RESULTS ARE A BLEND BETWEEN THE DIFFERENCES OBSERVED FOR THE WINTER AND SUMMER SEASONS. SIMILAR REMARKS ARE TO BE DONE FOR PRECIPITATION, WITH THE EXCEPTION THAT AN IMPROVEMENT STATISTICALLY SIGNIFICANT BELOW 25 MM THRESHOLD IS OBSERVED FOR BOTH FREQUENCY BIAS AND THREAT SCORES IN CANADA, NOTABLY IN THE WESTERN PART OF THE COUNTRY. 3.3 SUBJECTIVE EVALUATION OF THE ATMOSPHERIC COMPONENT THE GDPS-7.0.0 IN PARALLEL MODE WAS EVALUATED SUBJECTIVELY BY A TEAM OF OPERATIONAL METEOROLOGISTS FROM THE ANALYSIS AND PROGNOSIS (A AND P) SECTION OF CMC, BETWEEN MARCH 19 AND MAY 23 2019, FOR A TOTAL OF ABOUT 130 FORECASTS. THE ASSESSMENT WAS CARRIED OUT OVER NORTH AMERICA AND ADJACENT OCEANS FOR MEAN SEA LEVEL PRESSURE (MSLP) AND 500 HPA GEOPOTENTIAL HEIGHTS, AND OVER THE CANADIAN PROVINCES AND NORTHERN TIER OF THE UNITED STATES FOR THE QUANTITATIVE PRECIPITATION FORECASTS (QPF). DURING THE ASSESSMENT, MEAN SEA LEVEL PRESSURE AND 500 HPA HEIGHT FORECASTS WERE JUDGED TO BE EQUIVALENT FOR THE DAY 1 FORECASTS. GDPS-7.0.0 FORECASTS WERE EVALUATED AS BETTER BETWEEN 8 TO 12 PERCENT MORE OFTEN THAN THE GDPS-6.1.0 FORECASTS FOR DAYS 2 AND 3, WHILE THE TWO MODELS WERE JUDGED MORE OR LESS EQUIVALENT FOR DAYS 4 TO 7. THIS ASSESSMENT WAS IN AGREEMENT WITH THE OBJECTIVE SCORES. CONCERNING THE PRECIPITATION FORECASTS, OVER CENTRAL AND EASTERN CANADA, THE GDPS-7.0.0 FORECASTS WERE JUDGED TO BE BETTER 10 TO 15 PERCENT MORE OFTEN FOR THE DAY 2 TO 4 FORECASTS AND 8 TO 12 PERCENT MORE OFTEN FOR DAY 5 TO 7. OVER WESTERN AREAS, THERE WAS A DISCREPANCY BETWEEN THE SUBJECTIVE EVALUATIONS AND THE OBJECTIVE SCORES. THE HIGHER RESOLUTION GDPS-7.0.0 PROVIDES SHARPER FORECASTS WHICH CORRESPOND BETTER WITH OBSERVED PRECIPITATION PATTERNS, BUT HIGHER PRECIPITATION AMOUNTS ALONG THE WEST COAST AND ALONG THE ALBERTA FOOTHILLS WERE SEEN MORE NEGATIVELY BY THE OPERATIONAL METEOROLOGISTS. 3.4 VERIFICATION OF THE ICE-OCEAN COMPONENT THE ICE-OCEAN FORECAST WERE EVALUATED AGAINST THE ICE MAPPING SYSTEM (IMS), THE DAILY TM ANALYSIS AND VERTICAL PROFILES OF OCEAN TEMPERATURE AND SALINITY USING THE GODEA OCEAN VIEW CLASS 4 DATASET. THE NEW ICE COVERAGE ANALYSIS IMPROVES MARKEDLY THE SCORES DURING THE SUMMER PERIOD AND TO A LESSER DEGREE DURING THE WINTER PERIOD. THE RMSE OF THE SST IS SIGNIFICANTLY REDUCED IN BOTH PERIODS. WE HOWEVER NOTE SOME DEGRADATION OF THE BIAS (INCREASING WITH LEAD TIME), MOSTLY IN THE TROPICAL BAND. THE VERTICAL PROFILES AT DAY 10 OF THE FORECAST ARE GENERALLY IMPROVED IN BOTH BIAS AND RMSE FOR BOTH SALINITY AND TEMPERATURE AND FOR BOTH SEASONS --ALTHOUGH THE IMPROVEMENT IS MORE STRIKING IN TEMPERATURE-- THANKS TO THE NEW INITIAL CONDITION COMING FROM GIOPS V3.0.0. RESULTS OF THE PARALLEL RUN CONFIRMED THOSE OF THE FINAL CYCLES. 4. IMPACT ON DEPENDENT SYSTEMS FILTERING: IT IS NOTEWORTHY THAT ALL DIRECT OUTPUT ON PRESSURE LEVELS FROM THE MODEL ARE NOT SPATIALLY FILTERED ANYMORE. IN FACT, ONLY A FEW FIELDS PRODUCED IN POST-PROCESSING STILL FEATURE A SPATIAL FILTERING. SST ANALYSIS: USERS WHO PRESENTLY USE SEA SURFACE TEMPERATURE DATA FROM THE 0.20 DEGREE ANALYSIS SHOULD MIGRATE TO THE NEW 0.10 DEGREE ANALYSIS. UMOS: FOR THE GDPS-7.0.0, THE UMOS SYSTEM WAS TRAINED USING THE FINAL R AND D ASSIMILATION/FORECAST CYCLES FOR SUMMER 2016 AND WINTER 2017 AND COMPLEMENTARY INTEGRATIONS FOR WINTER 2018 AND 2019. VERIFICATIONS PERFORMED ON FORECASTS ISSUED DURING THE PARALLEL RUNS SHOW THAT UMOS CONTINUES TO IMPROVE SIGNIFICANTLY THE ACCURACY OF THE NUMERICAL FORECASTS ALTHOUGH ITS PERFORMANCE IS SLIGHTLY LOWER THAN THE PRECEDENT OPERATIONAL UMOS SYSTEM. HOWEVER, UMOS PERFORMANCE WILL GRADUALLY IMPROVE AS MORE CASES ACCUMULATE. SCRIBE: THE ONLY CHANGE IN THE GDPS PUBLIC SCRIBE MATRICES IS THE DISABLING OF A POST-PROCESSING OPERATION WHICH RESULTED IN UNDER- FORECASTING CLOUDS IN LOW CATEGORIES. CLOUDS FORECASTS WERE KNOWN TO HAVE A LOW BIAS IN CATEGORIES 1 TO 5: THIS IS NOW CORRECTED AND CLOUDS FORECASTS HAVE A BETTER RELIABILITY FOR ALL CATEGORIES. 5. PRODUCT AVAILABILITY WITH THIS UPDATE, THE PRODUCTS FROM THE GDPS DO NOT CHANGE BUT WILL BE DELAYED BY APPROXIMATELY 25 MINUTES. 6. SUPPLEMENTARY INFORMATION FOR A COMPLETE DESCRIPTION OF THE CHANGES, PLEASE REFER TO THE TECHNICAL NOTE WHICH WILL BE AVAILABLE ON JULY 3 VIA THE FOLLOWING LINK (SEE THE ENTRY REFERRING TO GDPS-7.0.0): HTTP://COLLABORATION.CMC.EC.GC.CA/CMC/CMOI/PRODUCT_GUIDE/DOCS/CHANGE S_E.HTML (LINK MUST BE TYPED ON A SINGLE LINE IN LOWERCASE) FOR QUESTIONS REGARDING THE NEW GDPS-7.0.0 AND ITS ASSOCIATED OUTPUT AND PRODUCTS, OR OTHER SPECIFIC QUESTIONS CONCERNING THIS OPERATIONAL IMPLEMENTATION, YOU CAN WRITE TO (USING LOWER CASE): EC.PRODUCTION-INFO.EC(AT)CANADA.CA GRIMES / ADM-MSC / SMA-SMC END