Meteo-GRID: Performing Local Weather Forecast

Using GRID Computing

C.-J. Lenz, D. Majewski

Deutscher Wetterdienst (DWD)

e-mail: claus-juergen.lenz@dwd.de detlev.majewski@dwd.de

• Introduction to Meteo-GRID

• Tasks of Meteo-GRID, data flow in Meteo-GRID

• Presentation of the GUI of the LM-Plugin

• Application example

Contents

Goal of Meteo-GRID

To provide

high-resolution short range weather forecasts

with the

relocatable nonhydrostatic “Lokal-Modell” (LM)

of the Deutscher Wetterdienst (DWD)

for any desired region in the world

via Internet and EUROGRID

Meteo-GRID

- ... is one of the application-specific GRID workpackages

of EUROGRID

- ...is done by close collaboration of three EUROGRID

partners:

- Deutscher Wetterdienst (DWD)

- Centro Svizzero di Calcolo Scientifico (CSCS)

- Centre Nationale de Récherche Scientifique - Institut du Développement et des Ressources en Informatique Scientifique (CNRS-IDRIS)

What`s special about Meteo-GRID ? (1)

- Real-time weather forecasting is a time-critical task,

a 48-h forecast must be completed in less than

60 minutes

- LM is a large MPP code of about 100.000 lines of code,

Fortran95, MPI for message passing

- Weather forecasting is computationally expensive

~ 4000 Flop/grid point and time step

~ 15 Tflop for a 48-h forecast (160 x 160 x 35 grid points,

grid resolution ~ 7 km)

~ 3000 sec at a sustained speed of 5 Gflop/s

What`s special about Meteo-GRID ? (2)

- Weather forecasting requires high band width for data

transfer

Forecast data (at hourly intervals): (48+1) x 20 Mbyte = 1 GByte

Transfer in less than 1 hour: 2.4 Mbit/sec

- “Weather” has large social and economic impact

worldwide (storms, floodings, snow, freezing rain ...)

Disasters (1)

@dpa@ Behr & Wojcik

Disasters (2)

www.dresden.de www.dresden.de www.dresden.de

@dpa

Tasks of Meteo-GRID (1)

- Selection of

model domain,

grid resolution,

forecast date and

forecast range,

forecast products

in a Graphical User Interface (GUI)

Tasks of Meteo-GRID (2)

- Derivation of

topographical data

for the selected

model domain

from high-resolution

(1 km x 1 km) data sets

at DWD

water

peat

clay

loamy clay

loam

loamy sand

sand

rock, concrete

ice, glacier

undefined

Tasks of Meteo-GRID (3)

- Extraction of

initial data and

lateral boundary data

sets for LM

from result data

of the global model GME

of DWD from the

ORACLE data base

Tasks of Meteo-GRID (4)

- Interpolation of GME results to the LM model grid

(interpolation program GME2LM) is performed on any

supercomputer available in EUROGRID

- LM forecast run is performed on any supercomputer

available in EUROGRID

Tasks of Meteo-GRID (5)

- Forecast data (up to 20 GByte in GRIB code) are

returned to the user via the internet and EUROGRID

AND/OR

- Visualization of LM forecasts ( 1 to 5 dimensional

graphics) on a computer within EUROGRID or on the

user’s computer

- Verification and validation of LM forecasts for any

region worldwide

Information and Data Flow (1)

1.1. Set up of LM-domain Set up of LM-domain

User

Global topographicaldata set (GIS),~ 7 GByte

Topographical data set(~ 1 MByte)

DWDDWD

GUI:GUI:Selection of- domain corners- grid resolution- forecast date- forecast range- forecast products

Calculation at DWD onSGI Origin, IBM RS/6000-SP (~ 15 min. wallclock time)

Information and Data Flow (2)

2. Define forecast date and range

GME data base (Oracle)

Hourly initial and lateral boundarydata sets on GME grid (~50 Mbyte)

UserDWDDWD

Extraction of GME results covering the LM domain at DWD (SGI Origin O 2000, IBM-RS/6000-SP) ~ 30 min. wallclock time

Information and Data Flow (3)

3.3. Perform GME2LM interpolation on EUROGRID HPC 1Perform GME2LM interpolation on EUROGRID HPC 1

User DWD

Topographical data set

Initial and lateral boundarydata sets on GME grid

HPC 1

GME2LMinterpolation of

GME results to LM grid

~1 MByte

~50 MByte

Initial and hourly lateral boundarydata sets on LM grid (50 MByte to 20 GByte)

Information and Data Flow (4)

4.4. Perform LM-forecast on EUROGRID HPC 2Perform LM-forecast on EUROGRID HPC 2

User HPC 2

LMcalculation of

weather forecast

50 MByte to20 GByte

LM-forecast data visualization

Initial and hourly lateral boundarydata sets on LM grid

HPC 1

50 MByte to 20 GByte

hourly forecast data of LM (50 MByte to 20 GByte)

Information and Data Flow (5)

5.5. Visualization of LM results Visualization of LM results

UserHPC 2

Visualizationof model results

Graphic files(up to 1 MByte)

up to 1 MByte

GUI of the LM Plugin (1)

GUI of the LM Plugin (2)

GUI of the LM Plugin (3)

GUI of the LM Plugin (4)

GUI of the LM Plugin (5)

GUI of the LM Plugin (6)

Application example

-Selection of hurricane Isabel /US East Coast,

18 - 20 August 2003)