Revelle
This presentation is the property of its rightful owner.
Sponsored Links
1 / 6

image structures: rain shafts, cold pools, gusts Separate rain fall velocity from air velocity PowerPoint PPT Presentation


  • 107 Views
  • Uploaded on
  • Presentation posted in: General

Revelle cloud and boundary layer Doppler remote sensing Simon de Szoeke, Alan Brewer, Chris Fairall . image structures: rain shafts, cold pools, gusts Separate rain fall velocity from air velocity turbulence retrieval– microphysical retrieval Diurnal and MJO composite statistics

Download Presentation

image structures: rain shafts, cold pools, gusts Separate rain fall velocity from air velocity

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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Image structures rain shafts cold pools gusts separate rain fall velocity from air velocity

Revelle cloud and boundary layerDoppler remote sensingSimon de Szoeke, Alan Brewer, Chris Fairall

  • image structures: rain shafts, cold pools, gusts

  • Separate rain fall velocity from air velocity

    • turbulence retrieval– microphysical retrieval

  • Diurnal and MJO composite statistics

    • rainfrequency and type

    • cloud and subcloud turbulence

    • shallow cumulus cloud top heights

O2 deck view

2-μm HRDL High-resolution Doppler lidar

motion-stabilized ≤ 0.5 degrees

3-mm W-band Doppler radar


Image structures rain shafts cold pools gusts separate rain fall velocity from air velocity

W-band cloud radar

HRDL lidar scanning

Continuously points at zenith

0

Shallow PPI

High PPI

Shallow RHI

10

  • Both instruments sample features in the atmosphere as they pass over.

  • Mean winds, turbulence, and spatially/temporally evolving wind field

  • Motion stabilized Doppler radial/vertical velocities.

Zenith

minutes

20

6 km

range


Revelle cloud and boundary layer doppler remote sensing simon de szoeke alan brewer chris fairall

Revelle cloud and boundary layerDoppler remote sensingSimon de Szoeke, Alan Brewer, Chris Fairall

  • HRDL and W-band cloud radar measure rain and clear air velocities:

    • coherent fronts and flows

    • turbulence

  • Separate rain fall velocity from air velocity

    • Pinsky et al. (2010) air velocity retrieval

    • cloud and subcloud turbulence

  • Combine with areal precipitation statistics from TOGA C-band radar.

    • composite over MJO convective & suppressed events

NOAA W-band cloud radar

October 19 hour (UTC)


Image structures rain shafts cold pools gusts separate rain fall velocity from air velocity

  • Stratiform precipitationhas steady fall velocity.

  • makes air velocity visible to radar.

  • DYNAMO has ~100 hours of stratiform rain.

Doppler velocity anomaly (m/s)

Doppler width (m/s)

Kelvin-Helmholtz

billows


Imaging fronts with radar and lidar

imaging fronts with radar and lidar

radar vertical

lidar RHI

A

B

lidar PPI

B

A

B

A

radar vertical velocity

Processing shows Nyquist-unwrapping and subtracting stratiform rain fall speed.

lidar horizontal velocities

Spatial sampling by lidar RHI and PPI scans show the front passing over the ship in radial Doppler velocity and backscatterretrievals.

see Alan Brewer’s talk and poster


Vertical velocity turbulence spectra

Doppler velocity anomaly (m/s)

 use to diagnose turbulence

vertical velocity turbulence spectra

height (km)

f–5/3

S2(m2 s–1)


  • Login