CPR Doppler Validation using WINDAS(L-band wind profiler)

Yuichi Ohno
National Institute of Information and Communications Technology (NICT)JAXA AOID 3: EarthCARE CPR and ATLID product validation using ground base remote sensors at Koganei
ESA-JAXA Pre-Launch EarthCAREScience and Validation Workshop
13–17 November 2023 |ESA–ESRIN |Frascati (Rome), Italy

A Doppler measurement function is one of the unique features ofEarthCARE/CPR and calibration using ground-based radar is important toget vertical Doppler velocity with good accuracy.
We are preparing ground-based W-band cloud radars at Koganei .
However, simultaneous observation chance will be few because of narrow
footprint size of CPR and revisiting cycle of 25 days.
In order to validate CPR Doppler velocity, we are planning to utilize thedata obtained by wind profiler networks (WINDAS) operated by Japan
Meteorological Agency.
WINDAS consist of 33 sites of L-band wind profilers from north to south ofJapan. Main object of WINDAS observation is horizontal windmeasurement in the troposphere, however vertical velocity is also
observed by vertical pointing observation.
Echo target of L-band wind profiler is not only atmospheric turbulent, butalso ice cloud and/or rain particle. We will identify ice cloud echo fromWINDAS observation. Then, we validate CPR Doppler velocity using its
vertical velocity. WINDAS measures vertical velocity every 10 minutes andis operated in 24 hours continuously.

WINDAS sites in Japan
WINDAS:1.357GHz Wind profiler
Main target: atmospheric turbulence
Horizontal wind profile with goodheight and time resolution
Sub target: Ice cloud and rain
Vertical velocity of cloud & rain particle

EarthCARE Doppler validation

Echo appearances (SPIDER & WINDAS)
W-band SPIDER（Koganei)

L-band WINDAS (Kumagaya）

Height (km)Valuable for
EarthCARE/CPR
Doppler validation
Ice
SnowRain

Ice
Snow

Water cloudvertical velocity (m/s)

AtmosphericEcho

Comparison of vertical velocity time-height sections between W-band cloud radar and L-band wind profiler
W-band Cloud Radar(HG SPIDER)

L-band Wind Profiler (LQ13)

2022/4/15

Example of distance between
EC Satellite path & WINDAS site

44.5km

39.7km32.0km 28.5kmDescendingday

AscendingnightANX_LONGTITUDE

Distance within 10km
16 stations
17 profiles
Distance within 1km
1 stations
1 profiles

ANX_LONGTITUDE

Distance within 10km
12 stations
14 profiles
Distance within 1km
1 stations
1 profiles

ANX_LONGTITUDE

Distance within 10km
14 stations
16 profiles
Distance within 1km
1 stations
1 profiles

ANX_LONGTITUDE

Distance within 10km
16 stations
20 profiles
Distance within 1km
1 stations
1 profiles

ANX_LONGTITUDE

Distance within 10km
18 stations
18 profiles
Distance within 1km
0 stations
0 profiles

Number of WINDAS sites near the EC satellite path

ANX0.0

0.2

0.4

0.6

0.8

<10km

1714162018

<1km

11110

Cloud/rain echo monthly mean appearance at each WINDAS site (2003-2005)
WINDAS Kumagaya

WINDAS Kumamoto

Cloud/rain echo monthly mean appearance at each WINDAS site (2003-2005)
WINDAS Miyako

WINDAS Obihiro

Summary
WINDAS is L-band wind profiler network in Japan operated by
Japan Meteorological Agency.
Using ice cloud echo of vertical beam of WINDAS, we plan tovalidate CPR Doppler velocity.
Since there are 33 wind profiler sites, it can cover the variation ofEarthCARE satellite paths. In more than 14 WINDAS sites, theEarthCARE/CPR validation data will be get within 10 km fromsatellite path in 25 days repeat cycle. Ice/Snow echo appearance isaround 20% through the season.

Comparison of Reflectivity time-height sections between W-band cloud radar and L-band wind profiler
W-band Cloud Radar(HG SPIDER)

L-band Wind Profiler (LQ13)

2022/4/15