1 / 18

Chuntao Liu Department of Atmospheric sciences, University of Utah Contributors:

Relationships between lightning flash rates over the tropics and subtropics and the vertical structures of precipitation radar reflectivity. Chuntao Liu Department of Atmospheric sciences, University of Utah Contributors: Edward Zipser 1 , Daniel Cecil 2 1. University of Utah

kenaz
Download Presentation

Chuntao Liu Department of Atmospheric sciences, University of Utah Contributors:

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. Relationships between lightning flash rates over the tropics and subtropics and the vertical structures of precipitation radar reflectivity Chuntao Liu Department of Atmospheric sciences, University of Utah Contributors: Edward Zipser1 , Daniel Cecil2 1. University of Utah 2. University of Alabama at Huntsville

  2. Riming electric charge separation Why there is a relationship between radar reflectivity and lightning flash? Keys : Graupel Temperature Super-cooled liquid water Takahashi and Miyawaki, 2002, JAS

  3. Define precipitation features using TRMM Precipitation Radar PR echo top height (km) Radar Precipitation Features (RPFs) Contiguous area with rainfall Properties of precipitation features Flash rate Temperature at 20, 30, 40 dBZ echo tops Maximum reflectivity at temperatures Area of 20, 30, 40 dBZ at temperatures Volume of 20, 30 40 dBZ at -5oC - -35oC IWC of 20, 30 40 dBZ at -5oC - -35oC

  4. Population of RPFs and those with lightning • 1998-2010

  5. Correlation between radar reflectivity vs. flash rate in precipitation features

  6. Correlation coefficient to flash rate in precipitation features Echo top temperature vs. Flash rate

  7. Correlation coefficient to flash rate in precipitation features area of reflectivity at temperatures vs. Flash rate Solid : land dotted: ocean

  8. area of reflectivity at temperatures vs. Flash rateauto-correlation among different part of storms removed Solid : land dotted: ocean

  9. Regional variation of correlations (I) Correlation coefficients

  10. Regional variation of correlations (II) Slope of linear relationship

  11. Summary • Flash rate is best correlated with the volume of the high reflectivity (> 30 dBZ) in the mixed phase region, confirming the importance of the presence of large particles in the charging process. • More flashes are generated over land than over ocean given the same volume of 30-35 dBZ in the mixed-phase region. • There are large regional differences in the correlations between radar reflectivity properties vs. flash rate. • Even with the similar radar reflectivity profiles to the oceanic systems, it is still easier to have lightning flashes over Amazon. Other factors must play important roles besides the graupel at mixed phase region in the lightning generation.

  12. 2-D histogram of RPFs and probability with lightning Temperature of 20 dBZ echo top vs. Temperature of 30 dBZ echo top

  13. Regional variation of lightning probability in precipitation systems

  14. Correlation coefficient to flash rate in precipitation features maximum reflectivity at altitudes vs. Flash rate

  15. Correlation coefficient to flash rate in precipitation features area of reflectivity at temperatures vs. Flash rate Solid : land dotted: ocean

More Related