OverviewOverview ofof TheThe CALIPSOCALIPSO MissionMission

DaveDave WinkerWinker NASA-LaRC, PI JacquesJacques PelonPelon IPSL/CNRS, co-PI

Cloud-Aerosol Lidar and Infrared Pathfinder Observations Research Themes

Improved understanding of the Earth’s climate system is a primary goal of the Scientific Community

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Science Objectives

Primary • Observationally-based estimates of direct and indirect aerosol radiative forcing • Allow improved characterization of surface longwave radiative fluxes and atmospheric heating rates • Improved model parameterizations of cloud-climate feedbacks

Secondary • Complementary measurements to validate and improve EOS data retrievals • Data to improve the representation of aerosols in chemical models • Monitoring long-range transport of pollutants • Polar stratospheric cloud climatology for chemistry applications

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations MISSION REQUIREMENT

“The science objectives will be achieved by flying the lidar, the Imaging Infrared Radiometer (IIR) and a wide field camera (WFC) in formation with AQUA for a three- year mission life.” CALIPSO Co-manifested with CloudSat and

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Synergies with the A-train

The atrain

aerosol thick clouds polarization, profiles, cirrus multi-angle cloud tops drizzle τ, P(θ) CERES: TOA fluxes Cirrus, De τ Aerosols and MODIS: cloud re, AMSR: LWP cirrus O2 A- band

OMI – absorbing aerosol

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Aerosol Radiative Forcing

1) Direct forcing 2) Indirect forcing Scattering and absorption Effects of aerosols on the of solar and terrestrial optical properties and radiation by aerosols lifetime of clouds

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations One Big Uncertainty: The Effects of Multilayer Clouds

20 LITE data, Western Africa, September1994

Thin Cirrus

Ice clouds

10 Altitude, km Altitude, Mixed-phase clouds Aerosols

0 20o N, 3o E LITE was able to penetrate cirrus to OD ~ 5 17o N, 6o E - 80% of profiles penetrated to top of boundary layer - expect similar from CALIPSO, with some averaging

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Mission Concept

• CloudSat CALIPSO Orbit: 705 km, 98° inclination, Aqua in formation with Aqua, CloudSat and Parasol PARASOL • Launch beginning of 2005

Aura • Mission duration: 3 years • Three co-aligned instruments: • 3-channel lidar – 532 nm || – 532 nm ⊥ – 1064 nm

Complementary Instruments Vertical distribution of • CloudSat radar (cloud profiles) aerosols and clouds • Aqua CERES (top-of-the-atmosphere radiation) • Imaging IR radiometer • Aqua AIRS / AMSU-A / HSB (atmospheric state) • Wide-field camera • Aqua MODIS (aerosol / cloud properties) • PARASOL (aerosol / cloud properties) Aerosol / cloud properties • OMI (aerosol absorption)

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Instrument Characteristics

X-Band Antenna Lidar Laser Nd: YAG, 2x110 mJ Wavelength 532 nm, 1064 nm Repetition rate 20.25 Hz Star Tracker Receiver telescope 1.0 m diameter Polarization 532  and ⊥ Footprint/FOV 100 m / 130 µrad Vertical resolution 30 - 60 m Horizontal resolution 333 m

Wide Field Camera (WFC)

Wavelength 645 nm Spectral bandwidth 50 nm IFOV / Swath 125 m / 60 km

Wide-Field Imaging Infrared Radiometer (IIR) Laser/Transmitter Camera Wavelength 8.7, 10.6, and 12.0 µm Spectral resolution 0.8-1.0 µm Imaging Infrared IFOV / Swath 1 km / 64 km Radiometer

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Imaging Infrared Radiometer

Warm Cold NedT 8.65 µm 10.60 µm 12.05 µm Blackbody 1 sigma value Deep Space (83% of pixels) @ 210 K 0.20 K 0.27 K 0.19 K @ 250 K 0.09 K 0.14 K 0.11 K

Filter transmissions for B1,B2 & B3 100

80 Global Cycle (40.92 s)

60 Filter Wheel BB DS DS DS DS Total Transmission (%) Transmission 40 8,184 8,184 8,184 8,184 8,184 40,92

20

0 7 8 9 10 11 12 13 14 Wavelength (µm) Filter B1 Earth Filter B2 Filter B3 Detector normalized response Objective+mirror

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Layer Detection: minimum backscatter

25

20 km 1 km day 20 night Assumptions: Sv Ci ∆z = 60 m 15 Cirrus sfc albedo = 5% solar zenith = 0o 10 single-shot Altitude (km)

5 LITE aerosol Stratus 0 1E-4 1E-3 0.01 0.1 1 10 Backscatter Cross-section (532 nm, /km/sr)

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations CALIPSO Detection Performance Simulation

1540 km

LITE, Shuttle (260 km) CALIPSO, Polar Orbit (705 km) Nighttime Daytime

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Layer Detection Simulation

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Satellite covers a fixed grid every 16 days

16-day repeat cycle produces a grid spaced by 172 km at the equator

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations L3 nighttime LITE data : 1 week 5°x10°

•First Class : Red Low Level Green Middle Level Blue High Level Black Clear Sky White No data • Second Class : 1 Low Level 2 Middle Level 3 High Level 4 Clear Sky * Flag ( Shot Nb < 100) S. Berthier, IPSL

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Correlative Measurement Strategy

Quid Pro Quo (QPQ) measurements (g/b) – coordinate with established programs – well-calibrated and characterized instrumentation – spatial matching requirements dictate the usefulness of the sites Field campaigns (g/b, a/c) (validation and science) – provide comprehensive measurement suites required to fully understand the retrieval performance – provide spatially and temporally matched data in any location – the number of independent samples obtained is usually limited – coordinated with other NASA and international activities Other – climatological data sets – large number of comparisons – coverage over regions without suitable ground sites – uniqueness of CALIPSO measurement suite

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Data Data Products Production Schedule Level

1b • Calibrated lidar profiles Starts after a 90-day on- • Calibrated IIR radiances orbit checkout phase • Uncalibrated WFC radiances (L+135 days). Thereafter, • Meteorological profiles data produced on 2-day lag • Lidar aerosol & cloud browse following receipt of all images required ancillary data (e.g., meteorological profiles).

2a • Lidar backscatter profiles Preliminary release after • Aerosol layer height/thickness 90-day on-orbit checkout • Cloud height/thickness phase (L+135 days). Data produced on 3-day lag thereafter. Archived after 18 month validation period

2b • Aerosol extinction, optical Archived after 18 month depth validation period • Cloud extinction, optical depth • Cloud ice/water phase • Ice particle size • Cloud emissivity

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations Science Team

R. Schwiesow, Ball Aero. S. Ackerman, U.WI M. Platt, CSU A. Heidinger, NOAA G. Stephens, CSU R. Hoff, UMBC Y. Kaufman, NASA/GSFC J. Pelon, Co-PI, IPSL P. Flamant, IPSL H. LeTreut, IPSL G. Megie, CNRS F. Breon, Atomic Energy Commission D. Tanré, Univ. of Lille

D. Winker, PI, NASA/LaRC T. Charlock, NASA/LaRC C. Hostetler, NASA/LaRC J. Reagan, U.AZ L. Poole, NASA/LaRC J. Coakley, OSU C. Trepte, NASA/LaRC B. Charlson, U.WA B. Wielicki, NASA/LaRC M. P. McCormick, Co-PI, HU N. Loeb, HU A. Omar, HU

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations