Topic 16 New and Maturing Sensors for Measuring Ice Cloud Properties

Transcription

1 Topic 16 New and Maturing Sensors for Measuring Ice Cloud Properties D. Baumgardner L. Avallone U. Bundke P. Field A. Heymsfield A. Korolev M. Krämer P. Lawson O. Mőhler D. Rogers O. Stetzer Workshop on In Situ Airborne Instrumentation: Addressing and Solving Measurement Problems in Ice Clouds Seaside, Oregon June 25-27, 2010

2 Measurement Issues Small ice properties (< 100 μm), water/ice discrimination, Low concentrations (poor sampling statistics) Avoiding Shattering and Splashing Liquid/Solid/Total Water, Ice Water Separation, Extinction Composition/Concentration of Ice Nuclei Platform dependent issues (e.g., high speed, rotary wing, unpiloted and commercial aircraft)

3 Measurement Issues Small ice properties (< 100 μm), water/ice discrimination, Low concentrations (poor sampling statistics) Avoiding Shattering and Splashing Liquid/Solid/Total Water, Ice Water Separation, Extinction Composition/Concentration of Ice Nuclei Platform dependent issues (e.g., high speed, rotary wing, unpiloted and commercial aircraft)

4 Maturing Sensors 2D-S (introduced 2004) HVPS-V3 (Introduced 199?) SID-1,2,3,2H (introduced 1996) VIPS (introduced 199?) PDA (introduced 2004) New Sensors CAS-DPOL (Introduced 2008) CPSD (To be introduced 2010) IBIS (Under development) Holodec (Introduced 2004?) 3V-CPI (Introduced 2010) Hawkeye (Under development)

5 Features: Enhanced sample area Fast response 10 μm resolution 2D-S (2D -Stereo) SPEC Inc.

6 HVPS-V3 (High Volume Particle Spectrometer) SPEC Inc Features Uses the 128-photodiode array and electronics that are used in the 2D-S and 2D-128 probes. The optics are configured for 150 micron pixel resolution, Maximum field of view of 1.92 cm Sample volume is 400 L s -1 at 100 m s -1

7 SID 1,2,3 (Small Ice Detector) University of Hertfordshire Features: 1-50 μm Shape discrimination Richard Cotton, S. Osborne, Z. Ulanowski, E. Hirst, P. H. Kaye, R. S. Greenaway: 2010 The Ability of the Small Ice Detector (SID-2) to Characterize Cloud Particle and Aerosol Morphologies Obtained during Flights of the FAAM BAe-146 Research Aircraft. J. of Atmospheric and Oceanic Technology, 27, pp

8 VIPS (Video Ice Particle Sampler) NCAR Features: Better size resolution Shape discrimination Large sample area

9 PDA (Phase Doppler Analyzer) Atrium Technologies Features: Wide size range: μm Shape discrimination Unaffected by coincidence

10 Depolarization CAS-DPOL (CAS with depolarization) Droplet Measurement Technologies Features: Water/ice discrimination > 2 μm (Depolarization) Shape discrimination (forward to back scatter) Asymmetry factor estimate Particle by particle From Forward to Back From depolarization 2:30 PM 3.5 Water to ice transition experiments at the AIDAchamber: results from the novel ice experiment NIXE-CAPS Jessica Meyer Transition Point Average Sphericity Fracion SIMONE Depolarization Scaled CPSD depolarization Sphericity Fraction UTC Seconds

11 CPSD (Cloud Particle Spectrometer with depolarization) Droplet Measurement Technologies Features: Water/ice discrimination>.8 μ Particle by particle Low shattering design

12 IBIS (Integrated Backscatter and Imaging Spectrometer) Droplet Measurement Technologies Features: Water/ice discrimination Particle by particle Size range μm Scattering 1-50 μm,.1 μm resolution Imaging , 10 μm resolution Co-located Center of focus Insensitivity to flow angle

13 HOLODEC (Holographic Detector for Clouds) Features: Large instantaneous sample volume 15.3 cm 3 3-D particle measurement Shape discrimination Spatial relationships

14 Features Combination of 2D-S and CPI 3 Views of the Same Particle. 3V-CPI SPEC Inc

15 Features Adds FFSSP to 3V-CPI 3V-CPI - Hawkeye

16 log(intensity) PHIPS Particle Habit Imaging and Polar Scattering Probe Karlsruhe Research Institute 8 Reconstructed Particle 7 Mie PHIPS Image 1 Image µm 100 µm 4 3 Features Stereo imaging for reconstruction of 3D particle shape and orientation Simultaneous measurement of the polar scattering function in angular range Angle ( ) Optics Electronics

17 Measurement Issues Small ice properties (< 100 μm), water/ice discrimination, Low concentrations (poor sampling statistics) Avoiding Shattering and Splashing Liquid/Solid/Total Water, Ice Water Separation, Extinction Composition/Concentration of Ice Nuclei Platform dependent issues (e.g., high speed, rotary wing, unpiloted and commercial aircraft)

18 Maturing Sensors CDP (introduced 2004) Probes with Korolev Tips(introduced 2000) FSSP Inlet removed New Sensors BCP CPSD IBIS

19 Features: Small Size Resistant to shattering Spatial relationships CDP (Cloud Droplet Probe) Droplet Measurement Technologies

20 Korolev Tips

21 BCP (Backscatter Cloud Probe) ** DMT Features: Small Size Resistant to shattering 2-70 μm size range ** Developed by DMT for detecting cloud from commercial airliners (European Union IAGOS project)

22 Measurement Issues Small ice properties (< 100 μm), water/ice discrimination, Low concentrations (poor sampling statistics) Shattering and Splashing Liquid/Solid/Total Water, Ice Water Separation, Extinction Composition/Concentration of Ice Nuclei Platform dependent issues (e.g., high speed, rotary wing, unpiloted and commercial aircraft)

23 Maturing Sensors Nevzorov Probes (introduced????) T-Probe (introduced 20??) WCM-2000 (introduced 20??) CSI (introduced 2004) Harvard instrument (total water) (introduced 20??) JPL instrument (isotopes) (introduced 20??) Colorado instrument (total water) (introduced 20??) FISH (introduced 1990) Cloud Extinction Probe (CEP) (introduced 2006) Cloud Integrating Nephelometer (CIN) (introduced 1998) In-Situ Lidar (Introduced 20??) New Sensors IKP

24 Nevzorov Probes Improved Geometry For ice particle spectra with Dmax<4mm, the IWC measured by the standard Nevzorov shallow cone is approximately 3±0.2 times lower than that measured by the Nevzorov deep cone and CVI.

25 T-Probe Features: Distinguish water and ice Robust A cylindrical sensor mounted normal to the airflow collects mostly water; a cylindrical sensor with a forward facing reentrant slot collects ice plus water ; a cylindrical sensor mounted along the airflow collects no particles and serves as a reference.

26 Multi-Element Water Content System (Model WCM-2000) SEA Four heated stainless steel elements, each with a different shape or size. Three of the heated elements are exposed directly to the air stream and incoming cloud water. A fourth element, the reference/comp element, is arraigned to be exposed to the airflow but not to incoming cloud water. Two different diameter LWC elements. The ratio of the LWC s measured by the two elements can be used with suitable calibration to indicate the MVD The instrument uses a scoop shaped sensor to collect and measure both liquid water (LWC) and ice crystals ( IWC).

27 CSI (Cloud Spectrometer and Impactor) DMT Features: TWC: g m -3 Complemented with the CDP

28 Harvard Total Water Features: Isokinetic flow Designed to completely evaporate particles <= 100 um Lyman-alpha detection of water vapor 35% uncertainty (2-sigma)

29 JPL Airborne Laser Infrared Absorption Spectrometer (ALIAS) Features: Only system that measures isoptopes Possibility of determining source of water Isokinetic flow 500 W probe heater, some evaporation of particles

30 Harvard, CLH, CSI University of Colorado Closed-Path Laser Hygrometer (CLH) Features: Low power, mid-infrared (1.37 m) tunable diode Detection for small and large mixing ratios Subisokinetic inlet to enhance sampling of particles IWC range: 0.01 mg m -3 to 1 g m 3 ±20% Fully autonomous, Power: < 50 W

31 FISH Fast In-situ Stratospheric Hygrometer inlet: total water sampling: 1 Hz range: ppmv accuracy: 6% + detection limit FISH calibration since 1990 (> 250 flights): balloon, Falcon, Cessna, Geophysica, LearJet, (HALO) + AIDA chamber experiments PI: C. Schiller, M. Krämer Zöger et al., JGR 1999 SPARC WAVAS 2000 Fahey et al., AquaVIT white paper, 2009 Meyer et al., AMT, 2010

32 HAI Hygrometer for Atmospheric Investigations Open-path TDLAS for gas-phase H 2 O + extractive cells for total water 2 channels 1.4 µm ppmv 2.4 µm ppmv 10 Hz (100 Hz) first HALO mission 2011 PI: T. Klostermann, V. Ebert, H. Saathoff S(T) [10-20 cm -1 /(molec*cm -2)] C B 20x vac [nm]

33 CIN (Cloud Integrating Nephelometer) LASER S4 S2 Cosine Masks S1 S3 Features: Direct measurement of scattering coefficient Estimate of asymmetry parameter Effective radius derived from complementary measurement of IWC

34 CEP (Cloud Extinction Probe Features: Direct measurement of extinction Resistant to shattering

35 IKP Inlet Diffuser Evaporator Hygrometer Orifice Plate Exit Control Valve

36 UAV-Capable In Situ Lidar with Very Large Measurement Volume for Cloud and Planetary Atmospheric Research SPEC Inc Boulder, CO Features: Dual wavelength in situ cloud lidar measures time-response of multiplyscattered photons within very large volume (billions of cubic meters) Volumetric measurements of Extinction, Liquid Water Content and Cloud Drop Effective Radius (Evans et al. 2003).

37 Measurement Issues Small ice properties (< 100 μm), water/ice discrimination, Low concentrations (poor sampling statistics) Shattering and Splashing Liquid/Solid/Total Water, Ice Water Separation, Extinction Composition/Concentration of Ice Nuclei Platform dependent issues (e.g., high speed, rotary wing, unpiloted and commercial aircraft)

38 Maturing Sensors CVI + SP2 CVI + ATOFMS CVI + AMS CFDC (Introduced 1996) Cloudscope (introduced 1998) New Sensors FINCH ZINC PINC

39 CVI IWC (gm -3 ) CVI + CFDC, SP2, AMS, ATOFMS IN, BC conc. (cm -3 ) SP2 ATOFMS IN counter ATOFMS SP IWC BC Mass CVI ON BC Mass Concentration (ng m -3 ) CFDC Seconds Downwind from Initial Cloud Penetration :22 5:32 5:42 5:52 6:02 Time (UT) IN BC SP2 scat Clear air scat Clear air BC

40 Cloudscope Features: Continuously monitors the presence and character of super micron particles. Particles are processed in real time by heating, which leads to liquid vaporization and complete crystallization; Hygroscopic character is demonstrated by growth under ambient situations of higher relative humidity. The prime advantage is the ability to track particle growth and evaporation, and to record the size and crystal form of any contained hygroscopic component. The instrument only functions out of cloud: in-cloud droplet collection is too frequent to allow undisturbed evaporation.

41 IN, BC conc. (cm -3 ) CFDC (Continuous Flow Diffusion Chamber) CSU < T < -40 C OPC :22 5:32 5:42 5:52 6:02 Time (UT) IN BC SP2 scat Clear air scat Clear air BC

42 Aerosol Aerosol Development chamber System-Bus FINCH University of Franfurt T P Td T T T Warm moist Warm dry Sheath Cold dry F F F F Features Mixing of 3 gas flows Total flow l/min Aerosol flow 1-10 l/min Activation of IN and CCN at preselected temperature and SS Virtual impactor (reduce airflow Distinguishes Xtals and supercooled droplets by circular depolarization ratio Fluorescence detector (bioparticles) FINCH BioaerosolDetector Td Signal processing Data Storage Unit Laser-beam Virtual Impactor Optical multiangular depolarization detector P Td P T System-Bus F P Zero Filter heated Dewpoint-mirror High High volume volume Pump Massflow Controller Pressure Sensor Exhaust T F Temperature Sensor

43 Measurement Issues Small ice properties (< 100 μm), water/ice discrimination, Low concentrations (poor sampling statistics) Shattering and Splashing Liquid/Solid/Total Water, Ice Water Separation, Extinction Composition/Concentration of Ice Nuclei Platform dependent issues (e.g., high speed, rotary wing, unpiloted or commercial aircraft)

44 Maturing Sensors Fast 2D-C 2D-S Fast FSSP (Faster response NCAR/RAF) (Faster response) (Faster Response) New Sensors Fast CDP IBIS BCP (Faster response) (Helicopters) (Commercial aircraft)

45 Continuing Issues and recommendations Many new instruments since 2002, how can they be validated/referenced to older instruments Many new instruments developed at research institute how do we make them available to broader community Modifications/improvements continue to be made on existing, individual instruments how to implement on other similar sensors? How can we encourage new developments by young investigators? Should there be stronger links between private business and research institute?