EarthCARE: The story so far – The First 30 years

Anthony Illingworth, Univ of ReadingFirst proposed July 1996
(black and white apart from the cover)

ESA-JAXA Pre-Launch EarthCARE Science andValidation Workshop
ESA-ESRIN Frascati
13-17 November 2023

1#1: MAY 1996

GRANADA;NINE CANDIDATES FOR PHASE A STUDIES“EARTH RADIATION MISSION"“RADIATION”?
Equator crossing time 1400. Orbit 600km
Comprising two elementsi) A set of instruments to be deployed on a satellite
GRACE “Global Radiation Aerosol and Cloud explorer”ii) A set of auxiliary measurements, utilizing observations made bysatellites missions, from the ground and elsewhere.
GRACE four instruments:
Nadir pointing cloud radar at 78 or 94GHz
Backscatter lidar at 1064nm.
Cloud Imager 0.55, 0.66, 1.6, 3.7, 11, and 12 mm
Broad-band radiometer for SW and LW fluxes at TOA(0.2mm – 4 mm and 4mm to 50mm)

FINAL VERSION 2023
– SAME APART FROM EXTRA 2.2mm CHANNEL2

IN 1994 RECEIVED COPIES OF TWO LETTERS QUESTIONING THE WISDOM OFLAUNCHING A 94GHz RADAR AND RECOMMENDING THE PROJECT BE DISCONTINUED:
ONE LETTER TO ESA AND ONE TO THE DIRECTOR GENERAL OF THE UK MET OFFICEi) SENSITIVITY INSUFFICIENT TO DETECT FAIR WEATHER CUMULUS.
ii) IWC FROM Z IMPOSSIBLE – just need one large ice particle for enormous errors.

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#1 MAY 1996

GRANADA:NINE CANDIDATES FOR PHASE A STUDIESGRACE LIDAR 1064um Sinusoidal scan - amplitude 25km. RADAR NADIR POINTING

EARTH RADIATION MISSIONNOT SELECTED
Subsequent discussions:Five radar beams
to sample same 25km swath?

4#2 JULY 1999

GRANADA:

FOUR CANDIDATES FOR PHASE A STUDIESEARTH RADIATION MISSIONNOW A SINGLE SATELLITE
WITH FOUR INSTRUMENTS:RADAR
LIDAR
MSI - MULTI-SPECTRAL IMAGER
BBR - BROAD BAND RADIOMETERii) A set of auxiliary measurements,utilizing observations made bysatellites missions,from the ground and elsewhere.
5NOW HAVE RADAR OBSERVATIONS OF CLOUD COVER FROM GROUND BASED RADAR
TO BE COMPARED WITH ECMWF CLOUD COVER (Robin Hogan)

25 OCT -31 0CT 1998

1 NOV - 7 NOV 1998
SURPRISE:
ECMWF MODEL DOES A GOOD JOB!
MOSTLY GETS CLOUDS IN THE RIGHTPLACE AT THE RIGHT TIME
6#2 JULY 1999

GRANADA;

FOUR CANDIDATES FOR PHASE A STUDIES“EARTH RADIATION MISSION"
but the idea of two elements – SATELLITE called GRACE dropped

Lidar - 1064nm 70mJ - non scanning.
Better to have co-located lidar/radar profiles“Very promising discussions with Japan – various meetings.
Similarities to Japanese ATMOS-B1 mission.
Possible scenario: NASDA (JAXA) contributes:
dual wavelength lidar, Fourier Transform Interferometer (FTIR) and a launcher.”( too ambitious – not well defined?

ADM (Atmospheric Dynamics Mission)“AEOLUS” selected….launched 2018.

7#3 GRANADASEPT 2001

FOUR CANDIDATES FOR PHASE A STUDIESNEW NAME: “EarthCARE”
Earth Clouds, Aerosols and Radiation Explorer
Coined by Jacques Testud

Non-native English speakers like this.
Native speakers –Initially sounds a bit pretentious.
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#3 SEPT 2001
GRANADA;
FOUR CANDIDATES FOR PHASE A STUDIESNEW NAME: “EARTHCARE”
RADAR - Doppler – particle terminal velocities/convection/identify drizzle.
LIDAR: 355nm high spectral resolution- Rayleigh (molecular) channel and Mie (clouds) channel with cross-polar.
MSI extra channel: 0.66 0.865 1.6, 2.2 8.7, 10.8 and 11.8 mm
BBR Broad band radiometer
Add another instrument. Fourier Transform Interferometer (FTIR) - retrieve profilesof water vapour and temperature profiles above cloud (flown on ADEOS)“EarthCARE will be realised through extensive cooperation between ESA, NASDA (nowJAXA)…..ESA is expected to contribute to the platform, ground segment and three
instruments ATLID, BBR and MSI while NASDA/CRL (JAXA) contribute two instruments
namely CPR and FTS and launch”
9SIMULTANEOUS LIDAR/RADAROBSERVATIONS FROM THE GROUNDIDENTIFY PERSISTENT THIN LAYERS OF
SUPERCOOLED DROPLETS WITHICE CRYSTALS FALLING OUTPERSISTING FOR HOURS…..
THIN LAYERS OF SUPERCOOLED DROPLETSHAVE A LARGE EFFECT ON THEIRRADIATION

In the models, the clouds were glaciating
rapidly, but observations show they persisted..
This led to a COLD BIAS OVER NE EUROPE
In the winter time10

#3 SEPT 2001 GRANADA;

EarthCARE not selected. No official feedback
Too complex – with five instruments???

#4 SEPT 2004

FRASCATI

EarthCARE Report for Assessment
Drop the FTIREARTHCARE SELECTED.
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2010 BUDGET TOO HIGH!
EXPERT COMMITTEE SET UP TO EXAMINE DESCOPING OPTIONS.
“The overall objective of this assessment, to be conducted by independent experts, is toprovide to PB-EO a report, summarizing the outcome of the assessment, documenting
which viable options exist regarding the continuation of the EarthCARE satellite
development.
In particular, the report shall address the current baseline together with viable de-scoping
options as well as the run-down cost of a possible cancellation.”
7 Feb 2011 - Committee reports.
The Science Board reaffirms the high scientific value of the EarthCARE mission.
There has been no change to the EarthCARE requirements since it was approved in
2004.
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