Calibration and Validation of EarthCARE’s
Cloud Profiling Radar Data Products

Ousmane O. Sy, S. Tanelli, R. Rodriguez Monje
Jet Propulsion Laboratory, California Institute of Technology, USA
ESA-JAXA Pre-Launch EarthCARE Science and Validation Workshop
ESA-ESRIN, Frascati, Rome, Nov 13-17 2023
© 2023, California Institute of Technology. Government sponsorship acknowledged.

EarthCARE GV in synergy with NASA/JPL activities❖ EarthCARE: 1st spaceborne profiling Doppler radar
to characterize atmospheric dynamics❖ Synergies with activities at JPL➢ NRC Decadal Survey 2017 recommendation:Doppler for NASA’s future spaceborne radarto study clouds, convection, precipitation
EarthCARE

Airborne/ground-based(APR-3, CloudCube)Spaceborne comparisons(RainCube to INCUS)

Numerical modeling tools(OSSE, suborbital-to-orbital, microphysics)

APR-3: Airborne Precipitation & Cloud Radar 3rd gen.
Campaigns since the last EarthCARE workshop (2018)
Jan-Mar ’12

ZenithKa

Jun-Jul ’17

APR3 (Ku,Ka,W)
APR2(Ku,Ka) + ACR(W)
APR2 (Ku,Ka)

Nov’15-Feb’16

Ku + Ka + W±25o

Aug-Sep’13
Jan-Feb ’03

Aug-Sep’21

Parameters
Ku-bandFrequency(GHz)
13.4
Polarization
HH, HV
Antenna eff. diameter
0.4 m
Antenna gain
34 dBi
Antenna sidelobe-30 dB
Antenna scan angle±25˚
Polarization isolation-25 dB
Peak power
200 W
Bandwidth
4 MHz
Pulsewidth3 - 20 ms
PRF (pulse rep. freq.)
5 kHz
Vertical resolution
60 m
Hor.res.(@10 km alt.) 800 m
Ground Swath
10 kmSens.(@10km range) 10 dBZ
Doppler precision
0.3 m/sKa-bandW- band
35.6
94
HH
HH
0.14 m0.3 m
34 dBi50 dBi-30 dB-30 dB±25˚±25˚500 W
1400 W
4 MHz
4 MHz3 - 20 ms 0.25,0.5, 1ms
5 kHz
5 kHz
60 m
50, 80, 150m
1000 m
200 m
10 km
10 km
-10 dBZ-35 dBZ
0.3 m/s
0.3 m/s

Apr-Oct ’19
Sep-Oct’22

Aug-Sep’10
Jul-Aug’07

A’16,S’17,O’18
Aug-Sep’06•••

Developed in 2014, NASA AITT / Dr. Steve Durden
PI: Dr. Raquel Rodriguez-Monje(Ku,Ka,W) collimated on nadir port; Ka at zenith•

Observables: reflectivity, mean Doppler, spectral width, LDRAPR-3 measurements: ORACLES 2018
➢ Drizzle in the S.E. Atlantic (30 Sep. 2018)➢ W-band Doppler moments
Reflectivity
Z(W)
[dBZ]

MeanDoppler
V(W)
[m/s]

SpectralWidthS(W)[m/s]

APR-3 measurements: CPEX-AW 2021
➢ Tropical storm Ida, West coast Jamaica (26/08/2021)➢ Multi-frequency Doppler moments
Reflectivity
Z(W)
[dBZ]

Z(Ku)
[dBZ]

DWR
Z(Ku - Ka)[dB]
Rain Index
GCOM-W1 (AMSR-2)
Dr. S. Hristova-Veleva

MeanDoppler
V(Ku)
[m/s]

CloudCube Instrument (airborne)➢ NASA-JPL ESTO IIP-19➢ 1st ultra-compact pulsed-compression
radar that combines (Ka/W/G)-band➢ PI: Dr. Raquel Rodriguez Monje➢ Field-campaign participations▪ CPEX: AW2021 & CV2022
o airborne: NASA DC-8
o ZCLOUDCUBE(W), with APR-3Parameters

Ka-bandW-bandG-band35.70.30 m
40 dBi
10 W
2 MHz
10-20 us
0.5 kHz75 m
346 m-7.2 dBZ

94.9
0.30 m
47 dBi
10 W
2 MHz
10-20 us
0.5 kHz75 m
127 m-14.6 dBZ

238.5
0.2 m
51 dBi
0.4 W
2 MHz
10-20 us
0.5 kHz
75 m
100 m-15.5 dBZ

Frequency (GHz)
Antenna eff. Diameter
Antenna gain
Peak PowerBandwidth
Pulsewidth
PRFVertical resolution
X-track Hor. Res. (@10 Km alt.)
Sens. (@10km range)

26/09/2022

Sensitive to clouds& light precipitation

APR-3 W-band Radar

Waveguide run
to the antenna

Attenuated byheavy precipitation
Oscilloscope tovisualize the TX pulse

W-band CloudCube prototype

https://esto.nasa.gov/forums/estf2021/Presentations/June3/Monje_ESTF2021_June3.pdf

CloudCube Instrument (ground-based, spaceborne)➢ Field-campaign participations▪ EPCAPE (DoE) 2023-2024:
o Ground-based (trailer)o Ka/W/G-bando Full Doppler
03/30/2023

Scripps pier

La Jolla, CA

JPL trailer

CloudCube
VIPR

Spaceborne CloudCube Radar Electronics compatible with SmallSats
G bandW band11 cm✓ Compact: <3U volumeper frequency channel✓ Low power RF: 20-30 W DC power
per frequency channel

10 cm

Ka bandEarthCARE GV in synergy with NASA/JPL activities
EarthCARE

Airborne/ground-based(APR-3, CloudCube)Spaceborne comparisons(RainCube → INCUS)

Numerical modeling tools(OSSE, suborbital-to-orbital, microphysics)

RainCube (PI Dr. Eva Peral, NASA ESTO Tech. demo)
2015
PECAN

2013
6U Concept

Airborne Demo of miniKaAR
Cross-track
angle [deg]miniKaAR (35.75 GHz) + KaRPDA 0.5 m

RainCube Sensitivity
and Resolution : confirmed

Distance from radar [km][K]

MASC Brightness Temperature (full Swath, 118±8 GHz)

RainCube Ka-band Reflectivity [dBZ]

Scattering
signatures MASC nadir (all chann).

Embedded
Convection
Melting Layer
Stratiform Rain
Ice particles
in Anvil

Purely Convective

Surface

EarthCARE Cal/Val
Workshop June 2018

RainCube Pulse Compression
performance: confirmed

RainCube 6U

RainCube 6U

RainCube 6U

5.5 kg, 10x20x30 cm3
RF Power: 10 W

Antenna deployment: Jul. 2018

Deployed from ISS July 2018

Launched to ISS May 2018

RainCube measurements: Aug. 2018 - Dec. 2020
RCmeasured

Artist concept

ZG,KaZGPM DPRKa

ZG,KuZGPM DPR
Ku

Calibration vs DPR
Z (RC) - Z (Ka) ~ 1.4 dB
Scientific Products From
the First Radar in a
CubeSat (RainCube):
Deconvolution, CrossValidation, andRetrievals”,
O.O. Sy et al.,IEEE TGRS, vol. 60, 2022

RC deconv,
Unattenuated

NEXRADS-band11→

Investigation of Convective Updrafts➢ NASA Earth Ventures Mission(Nov. 2021, in Phase B as of 13 Nov. 2023)➢ Launch: NET 2026
7

➢ PI: Prof. Susan van den Heever (CSU)➢ Payload:▪ 3 DAR: radars (RainCube-like)o Ka-band;o 1.6 m antennao 7 beams
o Mass: 7 kg
o resolution: 3 km (H), 240 m (V)o swath: 9 km
▪ 1 DMR: radiometer (Tempest-D-like)o 87, 165, 174, 178, 181±0.5 GHzo Mass: 3.8 kg
o resolution: 16 km
o swath: 1000 km•“Derived Observations From Frequently Sampled Microwave Measurements ofPrecipitation- Part I: Relations to Atmospheric Thermodynamics”,
Z.S. Haddad, O.O. Sy, S. Hristova-Veleva, G.L. Stephens, IEEE TGRS, vol. 55 (6), 2017•

“Derived Observations From Frequently Sampled Microwave Measurements ofPrecipitation. Part II: Sensitivity to Atmospheric Variables and Instrument
Parameters",
O.O. Sy, Z.S. Haddad, G.L. Stephens, S. Hristova-Veleva, IEEE TGRS, vol. 55 (5), 2017•

“A Distributed Small Satellite Approach for Measuring Convective Transports in the
Earth’s Atmosphere”, G. L. Stephens et al., IEEE TGRS, vol. 58(1), 2020

RCDPR

Target: vertical transport of air & waterby convective storms
Observables:,• Z(h,t), Z(h,t+30), Z(h,t+120)
ΔZ➢ derivatives(not Doppler)
Δt
ECPR

INCUS

EarthCARE GV in synergy with NASA/JPL activities
EarthCARE

Airborne/ground-based(APR-3, CloudCube)Spaceborne comparisons(RainCube → INCUS)

Numerical modeling tools(OSSE, suborbital-to-orbital, microphysics)

APR3 - Satellite under-flight: NUBF-Reflectivity“Comparison of GPM

APR3
science:
DPR and Airborne
Radar
Observations inGPM
DPR NUBFOLYMPEX”
S.L. Durden, S. Tanelli,and O.O. Sy,
IEEE GRSL, vol. 17(10)2020

Stratiform rainOlympic mountains,
Washington state•

GPM DPRreflectivity
Ku-band•APR3
reflectivity
Ku-band•APR3
dual-freq. ratio
Ku - Ka

3 Dec 2015

APR3 - in situ collocations: microphysical retrievals➢ Collocations:
APR3 - in situ microphysics - ground-radar D3R➢ Ancillary datasets: drop/radiosondes - reanalysis (ECMWF ERA5, MERRA)➢ Statistical microphysical analyses (forward/inverse)
APR3Z (W)APR3Z (Ka)

D3R
Z (Ka)

In situ“Impact of Mass–SizeParameterizations ofFrozen Hydrometeors on
Microphysical Retrievals:
Evaluation by Matching
Radar to In Situ
Observations from
GCPEx and OLYMPEx”

O.O. Sy, et al.
J. Atmos. Oceanic Technol.
vol 37, 2020

Model parametersm = aDbretrievals(Image Source: UND Aerospace)

IWC

DiameterSpreadHiDReSS: sub-orbital to orbital Doppler resampler➢ Acknowledgement: NASA Earth Science US Participating Investigator (ES-USPI) grants➢ Input: high-resolution suborbital Doppler measurements
air (SPIDER@NICT, APR3), ground (WACR@ARM)➢ Output: Simulated spaceborne Doppler products (Spectrum, PP, Z,V,S)
Snowstorm measured by SPIDER (NICT), Wakasa Bay, Japan, January 29, 2003

Used to develop corrections for➢ Aliasing

VTRUE(0.5 km)

SPIDER (NICT), WACR (ARM)(Sy et al. 2014a)➢ NUBF  gradient-Z
SPIDER (NICT), WACR (ARM)(Sy et al. 2014a)

RMSE = 1.27 m/s

VEC(0.5 km)
Level 1B
unfiltered➢ NUBF  deconvolution
APR-3(Sy & Tanelli 2022)

RMSE = 0.53 m/s

EVM filtered(min Errorvariance)➢ Broadening  deconvolution
APR-3(Sy & Tanelli 2022)➢ Broadening  hierarchical

REM filtered(max residueentropy)

RMSE = 0.87 m/s

RVA filtered(min residuevariance)

RMSE = 0.55 m/s

APR-3(Sy & Tanelli 2023)➢ Noisiness  adaptive filters
SPIDER (NICT), WACR (ARM)(Sy et al. 2014b)“Application of Matched Statistical Filters for EarthCARE Cloud Doppler Products”
O.O. Sy, S. Tanelli, P. Kollias and Y. Ohno, in IEEE TGRS, vol.52(11), 2014b

Thank you!
ousmane.o.sy@jpl.nasa.gov➢ CloudCube, APR3:➢ INCUS:simone.tanelli@jpl.nasa.gov

raquel.rodriguez.monje@jpl.nasa.gov
zsh@jpl.nasa.gov (Dr. Ziad Haddad)

RAINCUBE data sets
➢ RainCube data:

https://tcis.jpl.nasa.gov/data/raincube/

APR3 data sets➢➢➢➢

GCPEX, OLYMPEX:ORACLES 2016-18:
CAMP2EX 2019:
CPEX-AW21/CV22:https://ghrc.nsstc.nasa.gov/home/field-campaigns/
https://espo.nasa.gov/oracles/archive/browse/oracles/
https://www-air.larc.nasa.gov/index.html
https://ghrc.nsstc.nasa.gov/uso/ds_details/collections/
https://www-air.larc.nasa.gov/index.html