The A-SCOPE Project and After

Transcription

1 The A-SCOPE Project and After Pierre H. FLAMANT Fabien Gibert, Dimitri Édouart, Juan Cuesta, Fabien Marnas, Patrick Chazette, Didier Bruneau and ESA s A-SCOPE Mission Assessment Group 1

2 A-SCOPE Advanced Space Carbon and Climate Observation of Planet Earth 2005/08: call for ideas 2006/05: selection for phase /01: UCM in Lisbon, but CO 2 Total column content of dry mixing ratio (XCO 2 ) Canopy 2 Cloud & Aerosol layers

3 A-SCOPE Mission Assessment Group 3

4 A-SCOPE Mission Objective What Why How good do the measurements have to be? to decrease by a x 2 at least the uncertainty on retrieved CO 2 flux today CO 2 absorption line at 2 or 1.6!m A pulsed lidar enables to distinguish clearly between the contribution from surface and atmospheric scattering layers, and is therefore much less subject to biases than a passive instrument. It can also provide spin off products such as Canopy height and distribution 4

5 The After A-SCOPE Time A-SCOPE is not selected for next phase A for a launch in 2016 Let say the bottle was half full by lack of maturity in some key technologies (see presentation by Y. Durand) So, next chance will be 2020, for the Next ESA Earth Explorer call for Ideas In between, science and technology will go on! On-going works in the USA (LaRC, GSFC, JPL), Japan (NICT) and Europe (IPSL + DLR) 5

6 2-µm CO 2 Heterodyne-DiAL-Doppler Lidar Our starting point in nm nm 1 % accuracy in absolute value (no calibration), 6 Papers in peer review 6

7 Experimental Site in Palaiseau Paris Vertical CO 2 mixing ratio in the ABL using aerosols and troposphere using dense clouds as target Slant & Horizontal CO 2 mixing ratio using aerosols TReSS IPSL/LMD HDIAL Routine in situ measurements at IPSL/LSCE 5 km away 7

8 On-going Studies at IPSL Laser diode absorption spectroscopy for accurate CO 2 line parameters at 2 µm. Consequences for space-based DiAL measurements and potential biases Lilian JOLY, Fabien MARNAS, Fabien GIBERT, et ali collaboration with University of Reims. The presentation addresses the precision required on CO 2 spectroscopy and dedicated spectroscopy lab study for accurate Integrated Path Differential Absorption measurements from space to infer CO 2 surface fluxes with a 1 ppm total random error over 50 km horizontal and 0.1 ppm differential (i.e. interregional) bias (for constant bias doesn t matter) See presentation on Tuesday Turbulent CO 2 flux measurements by lidar and comparison with in situ sensors Fabien GIBERT, et ali See presentation on Tuesday Frequency stabilization Spectral purity Fabien MARNAS Contribution to PULSNIR project lead by ONERA, funded by ESA (final presentation Oct. 2008) 8

9 Canopy Canopy top Height Structure Crown 355 nm lidar Trunk Lidar beam Short vegetation 9

10 Environmental Issue: CO2 sequestration Monitoring of an Industrial Site From top to bottom Raman spectrometer (INPL) Dial Wind ABL Remote Sensing (IPSL-LMD) In situ analysis GCMS type (IFP) Flux box (INERIS) ATMOSPHERE Lidar Raman FTIR 5 m à 5000 m BIOSPHERE/ PEDOSPHERE: IR sensors (INPL) (INERIS) In situ probe (BRGM), In situ GCMS probe (BRGM) In situ correlation technique (INRA) Optical remote sensor (INERIS, INPL) Raman in situ using fiber (INPL, KAISER) Vegetation: 0 to 5 m Ground: - 5 m à 0 m Rocks: -150 m to - 5 m GEOSPHERE From crust down to reservoir: m CO2 reservoir 10 PHF 15 CLRC, Toulouse, June 2009

11 New Fiber laser for Lidar Application New program in two steps to develop 2-!m Lidar Led by Fabien Gibert and Dimitri Édouart Transportable 3D scanning DiAL + WIND Lidar (ANR) 2051 nm or a weaker line Objectives: CO 2, H 2 O, Wind, Flux, ABL structure, Aerosols Range distributed aerosols as target to provide signals Pulsed Ho open ring cavity laser, several mj, ns 100 W Tu fiber laser Heterodyne detection + direct detection - photon counting (detector issue!) High PRF (3-10 khz) Airborne nadir looking DiAL + w + canopy Lidar (CNES & CNRS) Objectives: CO 2, H 2 O, w, Canopy, ABL structure, Aerosols Both: i) Range distributed aerosols and ii) surface and canopy as target to provide signals Same technology but in a small aircraft Heterodyne detection golden rules: CNR!1 at farthest range of interest first and then PRF for multiple independent samples to achieve random error accuracy 11

12 CO 2 Monitoring: Passive Instruments from Space Thermal IR Near IR CHALLENGES: measurements impacted by thin clouds and aerosol layers, they can lead to biases. NIR measurements, no observation in winter at high latitudes 12

13 Observation techniques and mission concepts for analysis of the global carbon cycle Study initiated and conducted in the framework of A-SCOPE Led by F.-M. Bréon Added value of active CO 2 remote sensing from space in context of i) an existing surface network only, and ii) in the context of an existing surface network and passive satellites Emphasis and limitation of current assumptions that are used to reach the conclusion in the present work, and discussion on which are safe or dependent on the assumptions. Discussion of performance and limitation of tools: I) transport modelling and Ii) inverse methods, that are used for CO 2 flux retrieval and their improvements to fully benefit from satellite observation 13

14 Satellite Observations July 2005 ASCOPE OCO GOSAT SCIAMACHY AIRS Impact of cloudiness AIRS is not affected by low clouds and hence has a good global coverage, but the instrument is most sensitive to the upper troposphere. 14

15 A-SCOPE: Error reduction on weekly fluxes for µm 95 % 2 µm Same sampling and error patterns, but different vertical weighting function! Clear advantage of 2-!m weighting function because it gives emphasis to sink and sources at the surface 15

16 Hypothetical Surface Network, Plan A Working starting point: The budget of a satellite mission would allow for the construction and running costs for 418 new continuous stations, either surface based or using existing, none instrumented communication towers. Sampling: 41 tower sites: 4x per day; 377 continuous surface stations: 1x per day Accounting for stations elevation Total mismatch uncertainty as for existing surface network Final presentation early July

17 Internal WShop on CO 2 Lidar Remote Sensing 1 st in Paris, May nd in Tokyo, Nov rd in USA, early Oct

18 What Next We should keep our eyes and efforts on the 2020 target We have gained experience and confidence with A-SCOPE (ESA) + ASCEND (NASA) + For next future, what about a Carbon-Train concept like the A- Train (CALIPSO, CLOUDSAT, POLDER, AQUA, AURA) BIOMASS (ESA) is in phase A IASI, AIRS are operational 18

19 Acknowledgment Works funded by ANR (Agence Nouvelle de Recherche) CNRS/INSU CNES (French Space Agency) European Space Agency 19