european space agency esa unclassified – for official use page 1 adm-aeolus and earthcare esa’s...

European Space AgencyESA UNCLASSIFIED – For Official Use page 1

ADM-Aeolus and EarthCAREESA’s Earth Observation Lidar Missions

T. Wehr, P. Ingmann, A.G. Straume, A. Elfving, M. Eisinger, D. Lajas, A. Lefebvre, T. Fehr

European Space Agency

Second GALION Workshop

WMO Headquarters, Geneva, Switzerland

20-23 September 2010


ADM-Aeolus: The Atmospheric Dynamics MissionAeolus

Main ObjectiveMeasure wind profiles globally

Satellite• Polar sun-sync. orbit• Dawn-dusk• 400km mean altitude• Launch: mid 2013

PayloadHSR Lidar at 355nm (ALADIN)


WHICH INFORMATION IS NEEDED BY GENERAL CIRCULATION MODELS (GCMS)?

• When mass and wind fields are in approximate geostrophic balance, winds can be determined from temperature observations:– In the extra-tropics for large horizontal scales and for

shallow structures

• When geostrophic balance is not met, direct wind measurements are needed:– In the tropics – Globally for structures on small horizontal scales (e.g.

around topography) and for deep vertical structures

Need for independent wind profile observations


(ALADIN)(= height)

AEOLUS MEASUREMENT CONCEPT

Wind and atmospheric optical properties profile measurements are derived from the Doppler shifted signals that are back-scattered by aerosols and molecules along the lidar line-of-sight (LOS)


UV lidar (355 nm , circularly polarized)

Separate molecular and a particle backscatter receivers (High Spectral Resolution)

Line-of-sight points 35 deg from nadir and orthogonally to velocity direction to minimize contribution from satellite velocity

No polarization measurements

Adjustable vertical sampling of atmospheric layers with thicknesses from 0.25 – 2 km

Baseline change autumn 2010: Change from burst-to continuous mode operation.

Example of Aeolus vertical sampling

MEASUREMENT BASELINE


ATMOSPHERIC PRODUCTS

• Primary (L2b) product:– Horizontally projected LOS wind profiles

• Approximately zonal at dawn/dusk• 50 km averaged observations, 150 km spacing*• From surface to ~30 km• 24 vertical layers per channel with thicknesses

from 0.25 to 2 km • Accuracies: 2 (PBL), 2-3 (Trop), 3-5 (Strat) m/s

*Baseline change in 2010 will lead to longer observation lengths and removal (minimizing) of observation spacing

• Spin-off (L2a) products:– Aerosol and cloud profiles, e.g.

, σ, OD • cloud cover/stratification, cloud top heights, cloud type• aerosol stratification, aerosol type

Dusk/dawn orbit

CourtesyN. Žagar

Descending equatorialcrossing time: 6 AM


AEOLUS CLOUD AND AEROSOL PRODUCTS

• Direct and indirect effect of aerosols partly compensate for global warming by greenhouse gases– Large uncertainties– Observations of aerosol properties are needed

• ADM-Aeolus data on clouds and aerosol layers could be used directly by scientists for research on Atmospheric radiative budget and Water cycle applications

• ADM-Aeolus data could be combined with contemporary data available from operational space based visible and infrared radiometers in order to derive higher level data products on clouds and aerosols


• Main impact areas, as estimated by a Data Assimilation Ensemble at ECMWF:

– Jet streams over the oceans

– Above the oceans in the lower troposphere, e.g. western parts of the North Pacific and North Atlantic oceans, provided large enough cloud gaps

– Tropics

IMPACT OF SIMULATED AEOLUS WIND MEASRUREMENTS IN NWP

Courtesy D. Tan, ECMWF

Example of Aeolus wind profile impact in terms of 200 hPa (upper troposphere) zonal wind components (m/s)

Negative values: small ensemble spread -> positive observation impact


DLR Falcon 20 and HALO (High Altitude and Long Range Research Aircraft, modified Gulfstream G550) in April 2006

DLR further supports ADM-Aeolus activities in 2010 with

3 ground-based campaigns with the A2D, other lidars, windprofiler radar and radiosonde at DWD Lindenberg

2 airborne campaigns with Falcon or HALO aircraft with A2D and 2-µm wind lidar, co-located ground-based soundings

HALO aircraft delivered to DLR in November 2008www.halo.dlr.de


ADM-AEOLUS CAMPAIGN ACTIVITIES


CAL/VAL ACTIVITIES

• Call for Announcement of Opportunities (AOs) on Aeolus calibration and validation during its commissioning phase was issued 2007

• Areas covered by accepted projects (in total 16):– Validation using ground-based, airborne and satellite experiments,

providing independent measurements of wind profiles, clouds and aerosols;

– Experiments to assess accuracy, resolution, and stability of the Aeolus laser instrument ALADIN;

– Assessment and validation of the Aeolus retrieval and processing

• Due to launch delay, a Delta CAL/VAL call is planned for early 2011


STATUS OF THE AEOLUS PROGRAM

• The satellite and laser (ALADIN) subsystems have all been delivered and qualified on subsystem level

• Structural and thermal qualification on platform (Aeolus) level has been performed with a Structure-Thermal Model

• The transmitter laser is the most challenging for the qualification– The laser diode stacks have successfully completed their

qualification testing

– Amplifiers have successfully passed the first stability tests

– All optical components of the transmitter laser and optical path have been qualified for the high intensities over the 3-year lifetime

• Thermal vacuum qualification of the Power Laser Head is on-going

• Scheduled launch: 2013

European Space Agencypage 14

Payload• HSR Lidar at 355nm• W-Band (94GHz) Doppler Radar• Multi-spectral imager• Broad-band radiometer

Satellite• Polar sun-sync. orbit• 13:45-14:00 desc. node• 410km mean altitude• Launch: 2013

The Earth Cloud, Aerosol and Radiation Explorer (EarthCARE)

is a satellite presently under development by the

European Space Agency ESA in cooperation with

the Japan Aerospace Exploration Agency JAXA

OVERVIEW


Quantify cloud-aerosol-radiation interactions so they may be included correctly in climate and numerical weather prediction models to provide:

• Vertical distribution of atmospheric liquid water and ice on a global scale, their transport by clouds and radiative impact.

• Cloud overlap in the vertical, cloud-precipitation interactions and the characteristics of vertical motion within clouds.

• Vertical profiles of natural and anthropogenic aerosols on a global scale, their radiative properties and interaction with clouds.

• The profiles of atmospheric radiative heating and cooling through a combination of retrieved aerosol and cloud properties.

EARTHCARE SCIENCE OBJECTIVES


Aerosols: Vertical profiles of extinction and characteristics of aerosols

Aerosols: Vertical profiles of extinction and characteristics of aerosols

Clouds: Vertical profiles of liquid, supercooled and ice water, cloud overlap, particle size and extinction

Clouds: Vertical profiles of liquid, supercooled and ice water, cloud overlap, particle size and extinction

Vertical motion: Convective updraft and ice fall speedVertical motion: Convective updraft and ice fall speed

2-D Context: Clouds and aerosols horiz. structures2-D Context: Clouds and aerosols horiz. structures

Radiation and Flux: Broad-band SW & LW @ TOARadiation and Flux: Broad-band SW & LW @ TOA

Needs Techniques

Broadband RadiometerBroadband Radiometer BBRBBR

RadarRadar

LidarLidar

CPRCPR

ATLIDhigh sp. rs.

ATLIDhigh sp. rs.

EarthCARE instruments

Temperature and humidity from operational analysis

Doppler RadarDoppler Radar

CPR Dopplerized

Multi-spectral Imager

Multi-spectral Imager MSIMSI

EARTHCARE MISSION CONCEPT


SYSTEM OVERVIEW

Four instruments employed in synergy: 2 active: ATLID lidar + CPR radar vertical cloud/aerosol profiles 2 passive: MSI imager + BBR radiometer horizontal radiance fields

Stringent requirements for co-registration between instruments!

Industrial prime contractor: Astrium (D)

BBR


ATMOSPHERIC LIDAR (ATLID)

• Backscatter UV (355nm) with high spectral resolution receiver, bistatic

design• 3 channels receiver: Rayleigh, co-polar Mie, cross-polar Mie (circ. pol., tbc)

(separation Rayleigh-Mie by narrow bandwidth Fabry-Perot Etalon)

backscatter and extinction can be measured independently• Pulse repetition rate 74 Hz• Sampling: horizontal: 200m (=2x100m integrated), vertical: 100m• Receiver footprint on ground < 30 m• 3 deg off-nadir (backwards) pointing to reduce specular reflection on ice clouds• Level 1 product: attenuated backscatter profiles Built by Astrium (F),

with Selex Galileo (I)


CLOUD PROFILING RADAR (CPR)

• High power W band (94GHz) nadir-pointing radar with Doppler

capability• Antenna subtended aperture 2.5 m• Variable Pulse Repetition Frequency (PRF) 6100-7500 Hz• Sensitivity at least -35dBZ @ 20km height• Sampling: horizontal: 500m, vertical 100m (vertical resolution

500m)• Beam footprint on ground < 800 m• Doppler accuracy 1 m/s (for 10 km along-track integration and

-19dBZ)• Level 1 product: Reflectivity and Doppler profiles

Contribution of JAXA


• Nadir viewing push-broom imager• 4 solar channels Vis (670nm), NIR (865nm), SWIR1&2 (1.65µm & 2.21µm)• 3 TIR channels: 8.80µm, 10.80µm, 12.00µm• Swath: -35km to +115km (tilted away from sun to minimize sunglint)• Sampling (eff.): horizontal 500m x 500m• Calibration views: Sun, on-board warm blackbody, cold space• Level 1 product: Top-of atmosphere radiances and brightness

temperatures in 7 spectral bands

Built by SSTL (UK), with TNO (NL)

MULTI-SPECTRAL IMAGER (MSI)


• Short-wave (0.2µm-4µm) and total wave channel (0.2µm-50µm)• 3 views: nadir, forward (+50°), backward (-50°)• Linear microbolometer array detectors, ground pixels < 1km x 1km• Rotating chopper wheel (261 rpm)• Calibration views: sun, internal cold and warm blackbodies• 10km x 10km pixels spatially integrated in ground processing• Radiometric accuracy: 2.5 W/m2.sr (SW), 1.5 W/m2.sr (LW)• Level 1 product: Filtered top-of-atmosphere radiances short- and long-wave

Built by SEA (UK), with RAL (UK)

BROAD-BAND RADIOMETER (BBR)


ATLIDHigh spectr. res. Lidar

• feature mask• target classification• extinction, back-

scatter, depolarisation

• aerosol extinction, backscatter, type

• ice water content

CPR Dopplerized Radar

• feature mask• target classification• ice water content &

effective radius • liquid water content

& effective radius• vertical motion• precipitation / snow

BBRBroad-band radiances

• unfiltered solar radiance

• unfiltered thermal radiance

MSIVis/NIR/SWIR/TIR

• cloud flag / cloud type

• cloud phase • cloud top

temperature & height

• Effective cloud particle radius

• Aerosol optical thickness

GEOPHYSICAL (LEVEL 2) PRODUCTS

Single-Instrument Products (Level 2a)


GEOPHYSICAL (LEVEL 2) PRODUCTS

Synergistic Products (Level 2b)

Synergistic • cloud top height• aerosol optical thickness• aerosol type

Synergistic (variational scheme) • target classification• ice water content, eff. radius• liquid water content, eff. radius• aerosol extinction & type• rain water content, rain rate• cloud fraction & overlap

1D & 3D-MonteCarlo radiative transfer modelling:• flux and heating rate profiles• TOA LW & SW radiances; LW & SW fluxes

pixel size 10km x 10km

3-dim atmospheric scene construction pixel size 20km x 20km

Angular DependenceModels (ADM):• TOA LW flux• TOA SW fluxpixel size 10km x 10km

sceneclassification

closu

re

asse

ssm

ent

BBRBroad-band radiances

MSIVis/NIR/SWIR/TIR

ATLIDHigh spectr. res. Lidar

CPR Dopplerized Radar


Overall phasing

2009-10 Scientific algorithm development ATBD v1

2011 Processor implementation ATBD v2

2012 ATBD peer review, processor consolidation

Ongoing ESA activities

QuARL Assimilation into ECMWF models (nearly completed)

ICAROHS Multi-wavelength HSRL aerosol retrievals

DAME Doppler radar

SITS Broad-band radiometer unfiltering

RATEC Radiative transfer models

IRMA MSI clouds and aerosols incl. ATLID synergy

ATLAS ATLID retrievals + synergistic target class.

LEVEL 2 ACTIVITIES


Overall phasing

2009-10 Scientific algorithm development ATBD v1

2011 Processor implementation ATBD v2

2012 ATBD peer review, processor consolidation

Ongoing ESA activities

QuARL Assimilation into ECMWF models (nearly completed)

ICAROHS Multi-wavelength HSRL aerosol retrievals

DAME Doppler radar

SITS Broad-band radiometer unfiltering

RATEC Radiative transfer models

IRMA MSI clouds and aerosols incl. ATLID synergy

ATLAS ATLID retrievals + synergistic target class.

ICAROHS – looking beyond EarthCARE

DLR Activity

Using DLR campaign data, such as SAMUM I & II and Eyjafjallajökull surveillance flights,

for the development and testing of geophysical retrieval algorithms for potential future multi-wavelength HSR lidars.

Integration as module into EarthCARE Simulator (ECSIM)


The four instruments on board EarthCARE together:(CPR: Cloud Profiling Doppler Radar ATLID: Lidar MSI: Imager BBR: Broad-band Radiometer)Algorithms for these active sensors yield vertical profiles of microphysical parameters of cloud with its phase and aerosol with its species, and can detect drizzle and light rain.Especially doppler velocities of particles can be retrieved to give us new information.

Parameters: verticalcloud, aerosol,

drizzle, vertical motionfrom active sensors

Parameters: verticalcloud, aerosol,

drizzle, vertical motionfrom active sensors

Parameters: horizontalcloud, aerosol

from MSI

Parameters: horizontalcloud, aerosol

from MSI

Parameters: 3Dcloud, aerosol

Parameters: 3Dcloud, aerosol

collaboration with Model

Model Use:assimilationvalidation

Model Use:assimilationvalidation

Model Improvement:Cloud-Aerosolinteraction

Model Improvement:Cloud-Aerosolinteraction

Scene Generator&

Signal Simulator

Scene Generator&

Signal Simulator

Radiatve Transfer&

3D Montecarlo

Radiatve Transfer&

3D Montecarlo

Cloud SchemeImprovementCloud SchemeImprovement

Radiative Flux:BBR Data

Radiative Flux:BBR Data

Radiative Transfer CalculationVS.

BBR data (True)

Eart

hCAR

E

Algorithm development

IPCC

SCIENCE DERIVED FROM EARTHCARE

in cooperation with


MORE INFORMATION

European Space Agency

The Living Planet Programme

http://www.esa.int/esaLP/index.html

E-mail: [email protected]

ADM-Aeolus

Mission Scientist: Paul Ingmann, ESA-ESTEC

EarthCARE

Mission Scientist: Tobias Wehr, ESA-ESTEC


Backup slides


MISSION IMPLEMENTATION

Baseline Technology

• Direct detection UV lidar (355 nm) with Mie and Rayleigh receivers

• Mie and Rayleigh receivers can sample the atmosphere with different altitude steps

• The line-of-sight is pointing 35 deg from nadir orthogonal to the ground track velocity vector to minimize the Doppler contribution from satellite velocity

[H]LOS


MORE RECENT SCIENTIFIC STUDIES

• The yield, accuracy and impact of simulated Aeolus data in an operational NWP set-up. Used an ensemble method (ECMWF)

• Impact of Aeolus and alternative Aeolus sampling scenarios on predictive skills of Mid-latitudes high-impact weather systems (PIEW, KNMI)

• Impact of the PIEW Aeolus sampling scenarios for the modelling of Tropical dynamics (Univ Ljubljana with KNMI, MISU for EUMETSAT)

• Possible contribution to long-term database of cloud and aerosol optical properties; CALIPSO – Aeolus – EarthCARE (IfT and CNR-IMAA)

• The impact of Rayleigh-Brillouin scattering on the lidar atmospheric backscattered signal (Univ Amsterdam with Nijmegen, Eindhoven)


FURTHER PRE-LAUNCH ACTIVITIES

– Data processing: from Level 0 (raw data), Level 1B (calibrated wind profiles), Level 2A (cloud and aerosol products), Level 2B (scene classified temperature and pressure corrected wind profiles), to Level 2c (assimilated wind products)

– Pre-launch campaigns

– Vertical sampling strategy for various data applications (e.g. NWP vs. Stratospheric research)

– The influence of Rayleigh-Brillouin scattering on lidar backscatter: Controlled laboratory experiments for the validation of the Tenti S6 model for air, for a set of representative T and p

– Preparation of post-launch calibration and validation (CAL/VAL) activities


AEOLUS PRE-LAUNCH CAMPAIGNS BY DLR

1st and 2nd October 2006 and July 2007 with ALADIN airborne demonstrator (A2D)

Ground-based - Location: Lindenberg atmospheric observatory (DWD)- Instruments: Radiosondes, wind profilers, wind and backscatter

lidars, etc.

1st airborne November 2007- Target area: Middle Europe and Mediterranean Sea- Flights: 5 flights during 15 days with Falcon aircraft- Payload: A2D and 2-µm wind lidar and flights over ground stations

2nd airborne December 2008- Target area: Middle Europe and ocean- Flights: 7 flights during 11 days with Falcon aircraft- Payload: A2D and 2-µm wind lidar and flights over ground stations

3rd airborne September 2009- Target area: North-West Atlantic - Flights: 4-5 flights during 18 days with Falcon aircraft- Payload: A2D and 2-µm wind lidar

european space agency esa unclassified – for official use page 1 adm-aeolus and earthcare esa’s...

Documents

official use page

fehr european space

spacebased doppler wind

wind fields

direct wind measurements

projected los wind profiles

nm aladin slide

sight los slide