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NUMERICAL WEATHER PREDICTION (NWP)Kelompok 13 Departemen Geofisika dan Meteorologi Fakultas Matematika dan Ilmu Pengetahuan AlamInstitut Pertanian Bogor 2015

TOLONG BACA FOOTNOTE nya ya..1

Hilda Ayu P (G24120068)Isi foto kalian2Apa itu Model?

Model:

Alat yang digunakan untuk mensimulasi atau memprediksi pola perilaku sebuah sistem dinamika seperti Atmosfer.

(Resource: Kalnay, E., 2003: Atmospheric Modeling, Data Assimilation and Predictability)

Tipe-tipe modelNumericalConceptualEmpiricalHeuristicAnalytic

Types of models include:heuristic: rule of thumb based on experience or common sense (berdasarkan eksperimen atau kegunaan umum ex:)empirical: prediction based on past behavior (prediksi berdasarkan pola perilaku masa lalu, exconceptual: framework for understanding physical processes based on physical reasoninganalytic: exact solution to simplified equations that describe the dynamical systemnumerical: integration of governing equations by numerical methods subject to specified initial and boundary conditions

4Operational Model Overviews

ModelOwner LFM(NCEP) (Phased out)NGM (NCEP) (Phased out)ETA(NCEP) (Replaced by NAM, NAM-WRF)RUC(NCAR/NCEP) (Replaced by RAP)MM5(PSU / Air Force, etc.)GFDL(NCEP and GFDL Lab)COAMPS(Navy)WRF (NCEP)RegionalGlobalModelOwner GFS (Formerly the AVN/MRF) (NCEP)NOGAPS(Navy)GEM(Canada)ECMWF(European Union)UKMET(United Kingdom)

Numerical Weather Prediction (NWP)Prediction is very difficult,especially if it's about the future.Nils Bohr6

Apa itu NWP?www.themegallery.com

The technique used to obtain an objective forecast of the future weather (up to possibly two weeks) by solving a set of governing equations that describe the evolution of variables that define the present state of the atmosphere.

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SEJARAH SINGKATRecognition by V. Bjerknes in 1904 that forecasting is fundamentally an initial-value problem and basic system of equations already knownL. F. Richardsons (1922) attempt at practical NWPRadiosonde invention in 1930s made upper-air data availableLate 1940s: First successful dynamical-numerical forecast made by Charney, Fjortoft, and von Neumann1960s: Edward Lorenz shows the atmosphere is chaotic and its predictibility limit is about two weeks

SISTEM NWPNWP entails not just the design and development of atmospheric models, but includes all the different components of an NWP systemIt is an integrated, end-to-end forecast process system

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PROSEDUR SISTEM FORECASTINGwww.themegallery.comThe actual forecasting part of the model is only one part of a very complicated procedure ofData collection and assimilationForecastingPost ProcessingDistribution to users

Asimilasi data merupakan teknik pencampuran data dari sumber yang berbeda dengan tujuan untuk memproduksi seperangkat data baru yang konsisten dengan keadaan atmosfer.Metode asimilasi data terbaru, adalah mengekstrak informasi kondisi atmosfer dari observasi dan mengkombinasikannya dengan informasi dari model prediksi dan metode in imerupakan metode yang sangat powerful dalam pengembangan prediksi cuaca.

10DATA COLLECTION AND ASIMILATIONwww.themegallery.com

Fase Analisis DATA GRID 3DForcasting sebelumnyaObservasiASIMILASI

KOMPONEN MODEL NWPwww.themegallery.com

Governing equations

Persamaan massa, momentum, kelembaban ,termodinamika dan hukum gas.Ex: F = ma1>> Perkiraan yang digunakan untuk mengestimasi setiap istilah.>> digunakan untuk mengintegrasi model kedepannya dalam waktu tertentu>> Kondisi Batas2Numerical procedures

Approximations of physical processes 3Parameterizations

4Initial conditionsSistem Observasi Analisis ObjektifInitializationData asimilasi

PENJELASANNYA ADA DI MODUL. BACA2 AJA.12

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Grid spacing (resolution) defines the scale of the features you can simulate with the model.

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Good Numerical Forecasts RequireInitial conditions that adequately represent the state of the atmosphere (three-dimensional wind, temperature, pressure, moisture and cloud parameters)

Numerical weather prediction model that adequately represents the physical laws of the atmosphere over the whole globe

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ERROR IN NWP

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Sumber Kesalahan dalam NWPwww.themegallery.com

www.themegallery.comInitial Condition Errors

Observational Data CoverageSpatial DensityTemporal FrequencyErrors in the DataInstrument ErrorsRepresentativeness ErrorsErrors in Quality ControlErrors in Objective AnalysisErrors in Data AssimilationMissing Variables

Model Errors

Equations of Motion IncompleteErrors in Numerical ApproximationsHorizontal ResolutionVertical ResolutionTime Integration ProcedureBoundary ConditionsHorizontalVerticalTerrainPhysical Processes

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Example of error growth

Thank You !

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