Annual WWW Technical Progress Report

On the Global Data Processing System 2000

Meteorological Service Singapore

 

1. SUMMARY OF HIGHLIGHTS

For 2000, efforts were taken to ensure that all critical operational systems were Y2K ready and contingency procedures were also developed to address unforeseen Y2K-related disruptions. These efforts saw the smooth passage of the computer operations during the 1 Jan 2000 and 29 Feb 2000 (leap year) rollover.

By April 2000, the graphics visualisation and network infrastructure was upgraded with a higher faster network (Gigabit Ethernet) and a range of Silicon Graphics server and graphics visualisation equipment. For NWP, all operational computations have been successfully implemented to run on the NEC SX4 supercomputer.

 

2. EQUIPMENT IN USE

The equipment for the meteorological data processing system include a NEC SX4 supercomputer (16GB main memory, 128 GB disk storage, 16 Gflops), 2 Fujitsu M1600 mainframes, a 8-processor Silicon Graphics Origin 2000 server with Onyx2 graphics supercomputer, a few mini-computers (Fujitsu DS90s, VAX), workstations (SUN Sparcs, Silicon Graphics Octane/O2/Indy) and a network of PCs.

 

3. DATA AND PRODUCTS FROM GTS IN USE

Data

The following reports were received daily. Figures denote the daily average number for the respective reports.

SYNOP - 6500 reports

SHIP - 360 reports

PPAA - 360 reports

TTAA - 500 reports

AIREP (incl AMDAR) - 1300 reports

SATOB - 1200 reports

ECMWF - 126 bulletins

Products

GRIB ECMWF (from GTS)

GRIB EGRR (from SADIS system and via WMC/RTH Melbourne)

GRIB KWBC (from ISCS system)

GRIB JMA (from Distributed Data Base server of RSMC Tokyo)

 

4. DATA INPUT SYSTEM

Automated.

 

5. QUALITY CONTROL SYSTEM

Quality control checks are performed during the decoding, pre-analysis and analysis stages. These include climatological check, vertical and horizontal consistency check and gross error check.

 

6. MONITORING OF THE OBSERVING SYSTEM

Monitoring is carried out at the national level.

 

7. FORECASTING SYSTEM

7.1 SYSTEM RUN SCHEDULE

Operational NWP runs are carried out twice a day for the 0000 UTC analysis.

Early Run Final Run

Pre-processing : 0330 UTC 0530 UTC

Analysis : 0340 UTC 0540 UTC

GSM 3-day forecast : 0400 UTC 0600 UTC

LAM 2-day forecast : 0440 UTC 0640 UTC

GSM 4-10 day forecast : - 0700 UTC

 

7.2 MEDIUM-RANGE FORECASTING SYSTEM (4-10 days)

7.2.1 Data assimilation, objective analysis and initialisation

Global Analysis Model (GAM) : no change.

7.2.2 Model

Global Spectral Model (GSM) : no change.

7.2.3 Numerical weather prediction products

No change.

7.2.4 Operational techniques for application of NWP products

No change.

7.3 SHORT-RANGE FORECASTING SYSTEM (0-72 hrs)

7.3.1 Data assimilation, objective analysis and initialisation

No change.

7.3.2 Model

FLM-12 (40.0E-180.0E; 50.0N-45.0S) and VFM-13 (92.4E-125.8E; 20.6N-12.2S).

7.3.3 Numerical weather prediction products

No change.

7.3.4 Operational techniques for application of NWP products

NWP products such as winds, relative humidity and precipitation are used as guidance tools in operational forecasting.

 

7.4 SPECIALISED FORECASTS

      1. Model
      2. Atmospheric dispersion forecasts

        A long-range Lagrangian dispersion model and a forward trajectory model (adapted from the JMA).

        Wave forecasts

        The third generation WAM (Wave Modeling) model is run for two domains covering the globe (coarse run) and the Asia-Pacific region 60N-20S; 60E-180E (nested run).

      3. Numerical weather prediction products

Air dispersion models :

3-dimensional forward trajectories starting at 500m, 1500m and 3000m above the ground; time-integrated air concentrations within 500m layer above the ground; surface deposition (dry) of airborne pollutants.

7.4.4 Operational techniques for application of NWP products

The main application of the dispersion models is to generate forecast products for environmental emergencies such as episodes of smoke haze and volcanic ash, and nuclear accidents.

8. PLANS FOR THE FUTURE

With the upgrading of the computer resources, various new and upgrades to the range of meteorological products are in the process of development to improve the meteorological service to our users.

Higher resolution NWP models with more sophisticated physical parameterization schemes will be adapted and implemented to operate on the NEC SX4 and SGI Origin. These models will be developed for forecasts ranging from short-range weather forecasts to seasonal climate forecasts. To cater for certain specific users’ requirements, down-scaled models will be developed to operate on Linux-based PCs.