Cathy Clerbaux, Geocape workshop, May 2011 European Sentinel-4 and MTG-IRS Status Cathy Clerbaux CNRS, LATMOS/IPSL, Paris Stephen Tjemkes and Rolf Schlumann

Cathy Clerbaux, Geocape workshop, May 2011

European Sentinel-4 and MTG-IRS Status

Cathy Clerbaux CNRS, LATMOS/IPSL, Paris

Stephen Tjemkes and Rolf Schlumann Eumetsat

Heinrich Bovensmann, S. Noël, K. Bramstedt, P. Liebing, A. Richter, V. Rozanov, M. Vountas, J. P. BurrowsInstitute of Environmental Physics (IUP), University of Bremen, GermanyBen Veihelmann, Paul IngmannESA ESTEC, Noordwijk, The Netherlands

Inputs are from

EUM/MTG/VWG/10/0369EUMETSAT User Conference Issue 1MET/RSt 08.09.2010

MSGMOP/MTP

Observation mission:- MVIRI: 3 channels

Spinning satelliteClass 800 kg

Observation missions:- SEVIRI: 12 channels- GERB

Spinning satellite Class 2-ton

1977 2017 and 20192002

Atmospheric Chemistry Mission (UVN-S4):via GMES Sentinel 4

MTG to Secure Continuity and Evolution of EUMETSAT Services

MOP/MTP MSG

MTG-I and MTG-S

Observation missions: - Flex.Comb. Imager: 16 channels - Infra-Red Sounder- Lightning Imager- UVN3-axis stabilised satellites Twin Sat configuration Class 2,5 - 3 ton


MTG information on the ‘fast’ component of the hydrological cycle will improve warnings on the location and intensity of severe storm hazards,

The MTG enhanced information on convective/non-convective events, critical weather situations (~ fog, sand/dust storms, icing,..), fires, volcanic ash eruptions will allow surpassing present capabilities to provide warnings to the community,

MTG information on horizontally, vertically, and temporally (4-D) resolved gradients of moisture, wind, and temperature is expected to deliver a breakthrough regarding precipitation forecasts via assimilation into advanced non-hydrostatic regional models.

MTG information on carbon monoxide and ozone in the troposphere (IRS and UVN) and nitrous oxides generated by lightning will be a significant contribution to atmospheric chemistry and air quality applications,

MTG information on location and intensity of lightning will support warnings on lightning strikes for aviation and surface related business.

User Priorities on MTG Missions


MTG System Concept: Space Segment

MTG Space Segment Configuration• Twin Satellite Concept, based on 3-axis platforms

– Imaging Satellites (MTG-I) (MTG-I1/I2/I3/I4 : 20 years of operational service)

– Sounding Satellites (MTG-S) (MTG-S1/S2 : 15.5 years of operational service)

• The payload complement of the MTG-I satellite consists of• The Flexible Combined Imager (FCI)• The Lightning Imager (LI)• The Data Collection System (DCS) and Search and Rescue (GEOSAR)

• The payload complement of the MTG-S satellite consists of• The Infrared Sounder (IRS)• The Ultra-violet, Visible and Near Infrared Sounder (UVN). UVN is provided as GMES Sentinel 4 Instruments


2014 2016 2018 2020 2022 2024 2026 2028 2030 2032 2034 2036 2038 2040

MTG-I1

MTG-I2

MSG-4

MTG-I3

MTG-I4

MTG-S1 with S4

MTG-S2 with S4

20 years of Operational Service – Imaging Missions

15.5 years of Operational Service – Sounding Missions

Dec-17

Dec-22

Jan-26

Dec-30

Jun-19

Jun-27

MTG in Orbit Deployment Scenario

MSG-4

MTG-I1 Dec. 2017

MTG-I2 Dec. 2022

MTG-I3 Jan. 2026

MTG-I4 Dec. 2030

MTG-S1 June 2019

MTG-S2 June 2027

MTG Full OperationalConfigurati

on



MTG Provides a Total of Five Missions Compliant to the User Needs

The Flexible Combined Imager (FCI) = Full Disk High Spectral resolution Imagery (FDHSI), global scales (Full Disk) over a

BRC = 10 min, with 16 channels at spatial resolution of 1 km (8 solar channels) and 2 km (8 thermal channels)

High spatial Resolution Fast Imagery (HRFI), local scales (1/4th of Full Disk) over a BRC = 2.5 min with 4 channels at high spatial resolution 0.5 km (2 solar channels), and 1.0 km (2 thermal channels)

InfraRed Sounding (IRS), global scales (Full Disk) over a BRC = 30 min at spatial resolution of 4 km, providing hyperspectral soundings at 0.625 cm-1 sampling in two bands.

Lightning Imagery (LI), global scales (80% of Full Disk) detecting and mapping continuously the optical emission of cloud-to-cloud and cloud-ground discharges. Detection efficiency between DE=90% (night) and DE=40% (overhead sun)

UVN Sounding, implemented as GMES Sentinel 4 Instruments provided by ESA

Slide: 6

The Infrared Sounder

Heritage :• A LEO IR sounder (IASI) is currently operated by Eumetsat• Another LEO IR sounder (CrIS) is going to be launched by

NASA as part of the NPP payload (launch in late 2011)• The NASA/GIFTS concept

Spectral Spatial RadiometricCoverage

Two spectral ranges:LWIR: 700 -1210cm-1 MWIR: 1600 -2175cm-

1

Extended range (reduced performance): 680cm-1 to 2250cm-1

4 Local Area Coverage (LAC) zones

1 LAC every 15minutesFull Earth in one hour

(see next slides)

180 to 313K

Resolution

0.625cm-1 4km at SSP such to meet the NEDT spec

Accuracy and stability

such that the equivalent radiometric error is (roughly) below 50mK

Accuracy : 2KmStability : 0.5Km

(3 sigma)

Accuracy : 0.5KLong term stability : 0.3KMedium term stability : 0.1K

NEDT : 0.2-0.5K


~ 300 stares for Full Disc Coverage

~ 75 stares Local Area Coverage (LAC)

LAC-1/2/3/4 repeat cycle: 15 min including 2-3 min for calibration

Basic Repeat Cycle Pattern over 6 hours:

5 times LAC-3 plus LAC-4



LAC-4 (Europe) covered every 30 min

all LACs have at least 3 consecutive measurements with 30 min repeat cycle

MTG-IRS Operations Scenario

LAC -1

LAC -2

LAC -3

LAC -4

MTG-IRS Concept: Every 30 Minutes Europe

Slide: 8

IRS working principle

• The instrument works in a step-and-stare mode, with the Earth disc covered through a sequence of contiguous square sub-images

• With the current design, each sub-image (a dwell) takes 10s and covers about 650x650km2 (at SSP, the sampling being equiangular)

• Within a single dwell, a set of interferograms, one per detection element, is produced

• A spectral sounding is the result of the Fourier transformation of an interferogram from a single detection element

L0

L0

L1

L1 processing

Spectral sounding

InterferogramEarth

Dwell

Detection element

time

number

wave


MTG MissionsIRS – Benefits Summary

The IRS (30 min repeat cycle over Europe) will fill large spatial and temporal voids in the 12-hour time standard radiosonde observations and will allow time and space interpolation of moisture/temperature observations taken from the polar orbit.

The IRS derived information on low tropospheric moisture and its changes in time is expected to lead to a better depiction of the hydrological cycle in models, potentially providing better precipitation forecast.

The IRS will provide information on vertically resolved atmospheric motion vectors with improved height assignment, which in particular is beneficial for the tropical areas having only a weak coupling between the dynamic and thermodynamic atmospheric fields.

The IRS will provide information to identify pre-convective situations supporting NWC applications to forecast convective initiation.

IRS will support forecasting pollution and monitoring of atmospheric minor constituents through its capability to provide estimates of diurnal variations of tropospheric contributions of atmospheric trace gases as O3 and CO.


H2O(p) CO

T(p) Sfc O3 Sfc

Temp (CO2)

Surface, Clouds

O3

Surface, Clouds

H2O, CH4, N2O

CO

N2O,Temp (CO2)

Temp (CO2)

Surface, Clouds

700 – 1210 cm-1 1600 – 2175 cm-1

MTG-IRS mission will deliver unprecedented information on horizontal and vertical gradients of moisture, wind and temperature between measurements of individual radiosondes and hyperspectral soundings from the polar orbiting

satellites.

MTG-IRS Concept: High Spectral/Spatial sampling



The GMES Sentinel-4 sounding mission is achieved through the Ultraviolet, Visible & Near-infrared (UVN) Instrument accommodated on the MTG-S satellites– covering Europe every hour – taking measurements in three

spectral bands (UV: 305 - 400 nm; VIS: 400 - 500 nm, NIR: 750 - 775 nm)

– with a resolution around 8km.– spatial sampling of 8 km at 45°N

and spectral resolution 0.5 nm or better

The primary data products are O3, NO2, SO2, HCHO and aerosol optical depth.

MTG-S will Accommodate GMES Sentinel 4Ultraviolet Visible Nearinfrared (UVN)

Heritage :• LEO UV-vis-NIR sounders GOME2, OMI and

SCIAMACHY

Institut für Umweltphysik/Fernerkundung Physik/ElektrotechnikFachbereich 1OVERVIEW - Earth Observation Missions

handled by ESA

Services to initiate long term

monitoring systems and services

in cooperationwith EUMETSAT

Op Meteo

to better understand the Earth

System

Science

Earth Explorers

GOCE (Gravity and Ocean Circulation Explorer)

SMOS(Soil Moisture and Ocean Salinity)

CryoSat2(Polar IceMonitoring)

ADM/Aeolus(Atmospheric Dynamics Mission)

(Magnetic Mission)SWARM

EarthCare(Clouds, Aerosols & Radiation Mission)

METEOSAT Second Generation

MSG-1, -2, -3

METEOSATM-1, 2, 3, 4, 5, 6, 7

METEOSAT Third Generation

1990 2000 2010 2020 2030

Since 1977

GE

O

MetOp-1, -2, -3 Post-EPS

LE

O

ERS-1, -2

ENVISAT

Sentinel 3

Sentinel 5/5p

GMES in cooperation with EC

Earth Watch

Sentinel 1

Sentinel 2

Sentinel 4

Institut für Umweltphysik/Fernerkundung Physik/ElektrotechnikFachbereich 1Sentinel–4: GEO atmospheric mission

Instrumentation: • UV-VIS-NIR spectrometer • Use of thermal IR sounder

and cloud imager Geostationary orbit, at about 0o longitude Embarked on MTG-Sounder Satellite and operated by EUMETSAT

Yaw-flip at equinox

UVN

IRS

The GMES (Global Monitoring of Environment and Security) Sentinel program is driven by operational user requirements

GMES Sentinel 4, 5 and 5P focus on atmospheric chemistry

Institut für Umweltphysik/Fernerkundung Physik/ElektrotechnikFachbereich 1Sentinel-4/UVN Instrument Concept

Imaging Spectrometer in Geostationary Orbit Pushbroom in E/W direction N/S FOV: 4° E/W FOR: 6.8° 2 grating (dispersive) spectrometers

UV-VIS: 305 – 500 nm @ 0.5 nm

NIR: 750 – 775 nm @ 0.12 nm

CCD detectors cooled at 230 K Scan mirror:

E/W scan N/S for compensation of MTG yaw flip manoeuvre around equinox; seasonal shift in

latitude (per steps of 5 deg up to 10 deg)

High performance on board calibration sources (diffusers, lamp, LED) Instrument mass = 150 kg; power = 180 W; data rate = 25 Mbps

Ground

swath

Scanner motion

Telescope

Slit

Collimator

Dispersing elementRe-imaging lens

2D array detector

x

l

Spectral radiance

l

East

West

North

South

Institut für Umweltphysik/Fernerkundung Physik/ElektrotechnikFachbereich 1

Sentinel-4/UVN Performance Requirements

Band ID

Wavelength range [nm]

Species(In brackets:

scientific targets)

Spectralresolution

[nm]

Spectral sampling

ratio

SNR @50°N, 15:00 UTC,

Equinox, albedo 0.05 (UV-VIS) & 0.15 (NIR)

(per spectral sample)

UV 305 - 400 O3, SO2, (BrO), HCHO, AAI, AOD, Ring

0.5 3 200 - 1000

VIS 400 - 500 NO2, O4, (IO CHOCHO), AOD

0.5 3 1400

NIR 750 - 775 Cloud, Aerosol 0.12 3 600

Spatial resolution: 8 km at 45°N Coverage: Europe + Sahara Repeat Cycle: 1 hrJ. Burrows: UVN focuses only on limited spatial extent in order to save costs. The argument is that the funding for Sentinel 4 is from European

countries for European issues .It is clearly necessary to measure over the

African continent to assess biomass burning, the transport of dessert

dust, tropical urban pollution etc.

Institut für Umweltphysik/Fernerkundung Physik/ElektrotechnikFachbereich 1Phase A End-to-End error budget

(improved spectral stability)O3 [%] NO2 [%] HCHO [%] SO2 [%]

Tropospheric Column Error random system. random system. random system. random system.

Sensor (end-to-end, no error 03) this study 3 1 7 0,2 14 1 6 6Scenario Europe background polluted polluted polluted

Aerosol from literature 5 5 10 5 20 5 10Surface Albedo / BRDF 5 5 5 15 10 5 10Clouds 10 5 15 5 20 20 40stratosph. Separation 8 5 5 0 0 0 0profile knowledge 5 10 10 15 5x-section / incl. T dependence 5 7 2 2 5 12 5other 5 15

Total Scene w/o clouds 9 20 10 21 7 27 17 15with clouds 9 22 11 26 9 34 26 43

Total Scene & Sensor w/o clouds 9 20 12 21 16 27 18 16with clouds 9 22 13 26 16 34 27 43

Root sum square radom and syst. w/o clouds 22 25 31 24with clouds 24 29 38 51

MRD Req. 10 - 25 15 - 25 20 - 50 20 - 50Main References Liu JGR 2005 Boersma JGR 2004 DeSmedt ACP 2008 Lee JGR 2009

Liu ACPD 2009 Leitao et al. 2009 Wittrock 2006

S4 UVN - according to its Phase A concepts and performance - is capable to provide important data under the geophysical conditions relevant for Europe

Institut für Umweltphysik/Fernerkundung Physik/ElektrotechnikFachbereich 1

MTG-IRS, MTG-UVS/S4 UVN, and MTG-FCI and LI will provide unique and relevant data for tropospheric monitoring applications

O3, CO, NO2, SO2, VOC(H2CO, CHOCHO), AAI, Aerosol/PM

MTG-IRS S4-UVN on MTG MTG-FCI

S4 UVN Synergies on MTG for Tropospheric Chemistry and Air Pollution Applications

Synergies on MTG for Tropospheric Chemistry and Air Pollution Applications

!! L2 chemistry IRS products not planned for « Day 1 » operation

Courtesy H. Heskes, KNMI


3.2 Mbps

Raw data link - L-BandMSG

340 - 400 Mbps

MTGRaw data link - KA-Band

Meteosat evolutions:1977

1 Imager – 3 Channels2.25 km HR – 4.5 km30 Min RC

2002

1 Imager – 12 Channels1km HRV – 3km 15 Min RC

3.2 Mbps

340 - 400 Mbps

EumetCast

3 Mbps

EumetCast

>/= 60 Mbpsto be disseminated ?

MTG limited to 60 Mbpson future EUMETCast

(current assumption)

2017

1 Imager – 16 Channels0.5 & 1km HR – 1 & 2 km10 Min RC + LI

2019

1 IR Sounder- 2 Bands 4 km 60 Min RC + UVN-S4

MTG – New challenges in Information Technology



Conclusion: some thoughts

- Good interaction between agencies/scientific/industry is mandatory

Stephen Tjemkes (Eumetsat): “We arrived at the instrument specs because we had an excellent science team who performed in depth studies and were involved from the beginning. What could have been improved was the relation with the industrial team. In the end good communication between the science and the engineering team is critical. “

- Budget is always a concern. Compromises were made.

The needs of the met. community are driving the instrumental specs. Good collaboration with ESA through the GMES project.But see what we can do with IASI. Take the good side of it: continuity of obs., good spatial res, operational and NRT.

- Usefullness for chemistry and episodic episodesHigher probability to have clear pixels and also better timing for chemistry (time of day + thermal contrast), or episodic events is better. If S/N not high enough to detect some species we could average pixels (see talk tomorrow).

Slide: 20

Documents

Cathy Clerbaux, Geocape workshop, May 2011 European Sentinel-4 and MTG-IRS Status Cathy Clerbaux CNRS, LATMOS/IPSL, Paris Stephen Tjemkes and Rolf Schlumann