1 / 26

Heavy floods episodes on the 11 th and 12 th November 2008 South African case study

Heavy floods episodes on the 11 th and 12 th November 2008 South African case study Isaac Ngwana. Outline. General rainfall patterns Main weather systems Observation network Case study Model results and verification Conclusion. Rainfall patterns in SA.

ulysses-pennington
Download Presentation

Heavy floods episodes on the 11 th and 12 th November 2008 South African case study

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Heavy floods episodes on the 11th and 12th November 2008 South African case study Isaac Ngwana

  2. Outline • General rainfall patterns • Main weather systems • Observation network • Case study • Model results and verification • Conclusion Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  3. Rainfall patterns in SA Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  4. Main weather systems- responsible for flooding events TTT Tropical cyclones Cut off low Frontal system Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  5. Weather observation stations in South Africa • SURFACE OBSERVATIONS • 23 climate stations • 23 sea surface temperature stations • 25 weather offices • 35 electric _manual (aws manned) • 156 automatic weather stations – unmanned • 165 automatic rainfall stations • 1257 rainfall (monthly; ~50 provide daily data) • UPPER AIR OBSERVATIONS • 9 Upper air stations ( Including the ISLANDS – Marion and Gough) Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  6. Weather observation stations in South Africa Weather observation stations in South Africa Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011 Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011 6

  7. RADAR NETWORK in South Africa Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  8. Case study (11 & 12 Nov 2008) - general damage • 47 people were killed • Thousands evacuated • Roads and bridges swept away Document Reference: SMRF-PSN-NGW04-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  9. Warning System-print media Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  10. Early Warning System-print media cont… Document Reference: SMRF-PSN-NGW004-001-2011-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  11. 11 November 2008 Observations - 11 November 2008 Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011 11

  12. Observed 24 hr rainfall 11 & 12 Nov 2012 Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  13. 11 November 2008 Observations -12 November 2008 Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011 13

  14. Weather systems – 11 Nov 2012 Document Reference: SMRF-PSN-NGW004-001-2011-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  15. Observed weather -11 Nov 2008 Document Reference: SMRF-PSN-NGW004-001-2011-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  16. Observed weather 12 Nov 2008 Document Reference: SMRF-PSN-NGW004-001-2011-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  17. Observed weather -12 Nov 2008 Document Reference: SMRF-PSN-NGW004-001-2011-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  18. NWP Modeling in South Africa Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  19. NWP Modeling in South Africa Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  20. Modeling - weather systems 12 -48 hr forecast Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  21. 12 November 2008 Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  22. 12 November 2008 Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  23. Model -12 November 2008 Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  24. Eye ball verification Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  25. Warning System-SAWS website Document Reference: SMRF-PSN-NGW004-001-2011-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

  26. Conclusion • 11 &12 Nov 2008 flooding events were well forecast by the model • Forecast warning were issued in time • Necessary steps were taken by government dept. even though 47 people lost their lives • Good observation data bank, but sparse • Local data ingest might improve model forecast Document Reference: SMRF-PSN-NGW004-001-2012-05-09 Document Template Reference: AWC-PSN-001.1 Date of last revision: 26 August 2011

More Related