1 / 60

Topic 11

Topic 11 New Sensors, Platforms, Analysis Techniques and Integrated Systems for Measuring Ice Cloud Properties. D. Baumgardner M. Maahn Z. Wang Co-Leaders. A. Abdelmonem H. Bieligk U. Bundke J. Crosier, M. Gallagher I. Gulteppe M. Hamilton R. Jackson A. Johnson A. Korolev

keely
Download Presentation

Topic 11

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Topic 11 New Sensors, Platforms, Analysis Techniques and Integrated Systems for Measuring Ice Cloud Properties D. Baumgardner M. Maahn Z. Wang Co-Leaders A. Abdelmonem H. Bieligk U. Bundke J. Crosier, M. Gallagher I. Gulteppe M. Hamilton R. Jackson A. Johnson A. Korolev P. Kupiszewski P. Lawson A. Mensah B. Sierau J. Stith J. Ulanowski E. Weingartner Workshop on Measurement Problems in Ice Clouds Zurich, Switzerland July 5-6, 2013

  2. Presentation Guide Topic Theme and Objectives of the Working Group Brief Status of this Topic after the July, 2010 workshop What progress has been made in the last three years? What are the remaining unknowns and uncertainties and how do they impact our fundamental understanding of the atmosphere, climate change, weather and society in general?

  3. Presentation Guide Topic Theme and Objectives of the Working Group Brief Status of this Topic after the July, 2010 workshop (see BAMS article) What progress has been made in the last three years? What are the remaining unknowns and uncertainties and how do they impact our fundamental understanding of the atmosphere, climate change, weather and society in general?

  4. The central focus of Topic 11 is the assessment of new and evolving technology for measuring and analyzing the properties of ice in clouds and precipitation, including in situ and remote sensing techniques, ground based, airborne and space borne platforms and integrated suites of sensors. • The objectives of the working group are to: • summarize the strengths and weaknesses of current technology; • assess the technological progress that has made since June, 2010; and • identify gaps in our measurement capabilities where new technology or measurement approaches are needed.

  5. Presentation Guide Topic Theme and Objectives of the Working Group Brief Status of this Topic after the July, 2010 workshop What progress has been made in the last three years? What are the remaining unknowns and uncertainties and how do they impact our fundamental understanding of the atmosphere, climate change, weather and society in general?

  6. As of June 30, 2010, from the BAMS meeting summary, issues related to measurement capabilities. 3) Currently available instruments are limited by problems caused by ice crystal shattering and sample volume uncertainties for cloud particles smaller than 50 μm. Although consistent and reliable measurements of ice crystal size distributions can be obtained for particles larger than 400 μm, given sufficiently long integration times, large uncertainties still remain at smaller sizes. 4) New instruments are becoming available to differentiate liquid droplets from ice crystals at sizes less than 50 μm by detecting their shapes from forward light scattering and depolarization signals.

  7. Presentation Guide Topic Theme and Objectives of the Working Group Brief Status of this Topic after the July, 2010 workshop (see BAMS article) What progress has been made in the last three years? What are the remaining unknowns and uncertainties and how do they impact our fundamental understanding of the atmosphere, climate change, weather and society in general?

  8. 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) • Issues related to passive and active remote sensing

  9. 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)

  10. In Situ Related to Small Ice, Water/Ice Discrimination (Needs editing. ) Maturing Sensors (How far back do we go?) SID-3,2H (introduced 20??) – Results from ICE-T (Johnson/Field) Holodec (Introduced 2004?) – Anything new? (Contact Jacob) CAS-POL (Introduced 2008) – Lab/Aircraft results (Jessica/Martin) PN (Introduced 1997) - New Sensors BCP (Introduced 2011) – Airbus results (Darrel) BCP-POL (Introduced 2012) – BAE-146 results (Darrel/Martin) CPSPD (Introduced 2011 3V-CPI (Introduced 2010) – ICE-T? (Paul L.) Hawkeye (Introduced 201?) –Global Hawk? (Paul L.) PHIPS-HALO (Introduced 2011) MASC (Introduced 2012) – Results from Tim Garrett Polarsonde (Introduced 2012?)

  11. SID-2H vs. FSSP

  12. SID-2H vs. FSSP-100: All Ice and Water Cases RF11 cloud pass at -13°C (all ice) RF04 cloud pass at 7°C (all water) • Penetration at base of shallow maritime cumuli • 2D-C images = small water drops • FSSP-100 >> SID-2H concentration • SID-2H shouldn’t be trusted in warm clouds • SID-2H derived particles shape dominated by spheres, small number of irregular particles • Penetration through dying cloud • 2D-C images = small ice particles; mostly aggregates aswell as rimed columns & dendrites, very few drops • SID-2H ~ FSSP-100 concentration • SID-2H derived particles shapes dominated by spheres and irregular particles

  13. SID-2H vs. FSSP-100:‘First Detectable Ice’ Case RF04 cloud pass at -5°C • Penetration within 500 m of cloud top • 2D-C images = drops, no ice • FSSP-100 >> SID-2H concentration • SID-2H derived particles shapes, irregular particles, and columns • Ice predominately observed by SID-2H in updraft/downdraft interfaces Data from Johnson et. al – Submitted to J. Tech.

  14. 200µm 500µm 500µm 500µm 500µm Polar Nephelometer : phase discrimination Case study : Nimbostratus arctic cloud

  15. Results from BCP

  16. Change in Polarization State to Detect Water Phase Changes Implementation in CAS-POL and CPSPD

  17. PHIPS-HALO: Particle Habit Imaging and Polar Scattering Probe PHIPS-HALO is an optical sensor designed to measure, simultaneously, the 3D morphology and the corresponding optical properties of individual cloud particles. It is composed of two combined optical systems. The first system measures the polar scattered light from cloud particles with a resolution of 1° for forward scattering directions (from 1° to 10°) and 8° for side and backscattering directions (from 18° to 170°). The second system is a stereo imaging system composed of two identical camera-telescope assemblies and a pulsed flash Laser. The images are produced as particles shadows on the CCD of each camera. The measured particle size range is 5 to 800 µm

  18. Sample result: Cam.2 Cam.1 Abdelmonem et al. Atmos. Meas. Tech., 4, 2125–2142, 2011

  19. Example of CAS-POL Measurements Here

  20. Example of CPSPD Measurements

  21. Results from the Multi-Angle Snowflake Camera

  22. Polarsonde: A low-cost polarisation backscatter sonde • A probe for cloud ice/ supercooled liquid • Originally conceived for support of aviation forecasting • Potentially useful for study of cloud structure and for support of modelling • Transmits linearly polarised light from LED (6 kHz mod’n.) • Photodiodes with perp. and parallel polarisers • and lock-in amplifiers • Measures linear “depolarisation” • Interfaces to RS92SGP radiosonde • Uses Vaisala RSA921 Ozonesonde interface Murray Hamilton, Huichao Luo; University of Adelaide

  23. Launch at Summit Camp: 18 July 2012Cloud present at ca 3400 m and ca 5500 m

  24. data from 10 m on tower at SummitLarge depolarisation implies ice, small (ca 0.3?) implies liquid. (temp and RH for 1st week Nov. follow) After 24-hr darkness … did not behave well in sunlight. Fog monitor (faulty) and particle size spectrometer also at 10 m Modified since to be insensitive to sunlight.

  25. Validation of polarsonde • Cloud particle microscope; Huichao Luo • Relatively low-cost … Light weight … balloon borne • Collaboration with ICECAPS and Greenland Isotope projects. • Monte-Carlo modeling of scattering in cloud • Multiple scattering is a significant confounding process • Uses Mie theory for liquid droplets • typical linear depolarisation • Approx. equal contributions to depolarisation from geometry and multiple scattering • Model for ice crystals in progress – guidance is sought at Zurich workshop!

  26. Remote Sensing Related to Small Ice, Water/Ice Discrimination (Needs editing. ) Maturing Sensors (How far back do we go?) New Sensors (Need descriptions and example results)

  27. 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)

  28. Maturing Sensors CDP (introduced 2004) Probes with Korolev Tips (introduced 2000) FSSP Inlet removed HOLODEC New Sensors BCP CPSPD Analysis techniques?

  29. 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, Light Extinction • Composition/Concentration of Ice Nuclei • Platform dependent issues (e.g., high speed, rotary wing, unpiloted and commercial aircraft)

  30. In Situ Total Water Maturing Sensors (Anything New? Which ones do we keep?) Nevzorov Probes (introduced ????) FISH (introduced 1990) Cloud Extinction Probe (CEP) (introduced 2006) New Sensors IKP

  31. Remote Sensing (Needs editing with specific examples) • (Cloud) Radars • New technologies: • multi-wavelength (also form space -> GPM) • Exploiting higher moments or even full Doppler Spectrum • Attenuation proportional to ice at mm wavelengths • Polarization • shorter averaging times to reduce influence of turbulence • Challenges: • Absolute Calibration • processing of large data amounts

  32. Z-SWC relation dependent on particle habit and size distribution • Accuracy can vary by more than one order of magnitude • We have to measure more than only reflectivity! SWC: snow water content Z – SWC relations for radar Z mm6m-3 Liu, 2008: SWC gm-3 M. Kullie, Univ. of Madison

  33. Multi Frequency approach • Dependency of differential reflectivity on particle type: Kneifel et al., JGR, 2011 Difference Ka and Ku band [dB] Difference Ka and W band [dB]

  34. Exploration of higher radar moments • Doppler radar measure not only reflectivity, but also Doppler spectrum and higher moments, such as Spectral Width, Skewness and Kurtosis • Shape depends on particle density, shape, fall velocity, PSD and turbulence

  35. Exploiting attenuation Petty and Huang, JAS, 2010 • Extinction has less variability in respect to particle habits, but stable connection to mass. • Only for high MW frequencies (> W-band) • Measurement: • 2nd, not attenuated frequency (e.g. Kband) • Radio link

  36. Remote Sensing (Needs editing with specific examples) • Radiometers • New technologies: • Polarization • Exploiting higher frequencies • Increasing number of observations from space • Challenges: • receiver calibration • inversion of forward models (retrieval) • getting climatologies for retrieval • going beyond path properties

  37. TB: brightness temperature (= intensity of radiation) • Snow/ice scatters thermal surface emissions: • TB depression measured from space • TB enhancement measured from ground Passive microwave signals during snowfall U. Löhnert, U. Cologne

  38. typical winter case Microwave spectrum during snowfall sensitivity to particle habit U. Löhnert, U. Cologne • Frequencies > 120 GHz needed for detection of snow and ice • Signal sensitive to ice AND water • Sensitivity: ~ 8 - 10 K per 0.1 kgm-2 SWP at 150 GHz

  39. Polarization Long term statistics of measurements taken at Mnt. Zugspitze at150 GHz, elev= 34.5° Polarization due to non-spherical shape of ice particles. Signal only visible, if SCLW is not present! Xie et al., JGR, 2012 Polarization Difference = TBv - TBh

  40. Remote Sensing (Needs editing with specific examples) Lidars, passive vis & IR Lidars: Elastic lidar (all platform): backscattering and depolarization Raman lidar (ground +airborne): cloud extinction + ice water content+ effective size High spectral resolution lidar: cloud extinction + depolarization Passive: VIS+IR: MODIS improved ice cloud retrievals after intercomparison with CALIPSO optical depth Microwave: AMSR-E, IWP

  41. To be added: • New Analysis Techniques • Multi-sensor retrievals • Multi-probe synergy • IC-PCA • New and emerging measurement platforms • UAV • Balloon-borne • New integrated measurement techniques • Multi-sensor integrations from ground, airborne, and satellite. • Airborne integration of remote sensing and in situ sampling.

  42. New observatory of cloud and precipitation properties from ground-based remote sensing in East Antarctica (HYDRANT project, ees.kuleuven.be/hydrant): • Equipment: ground-based remote sensing using low-maintenance and robust instruments (ceilometer, infrared pyrometer and MRR) • Products: cloud height, distinction of ice vs liquid-containing clouds, precipitation intensity and height (including virga), precip vs blowing snow • Integrated measurements: combined with meteorology, radiation, accumulation (=> effects on SMB/SEB) + Regional Climate Model evaluation + potential for CALIPSO/CloudSat collocated analysis • Contact: N. Van Lipzig, I. Gorodetskaya (KUL, Belgium) Princess Elisabeth base Powered by wind and solar E Unmanned during March-Nov (satellite connection) CL31 Ceilometer (910 nm) Infrared pyrometer (8-14 µm) Micro-rain radar (24 GHz) AWS: meteorology, radiative fluxes, accumulation Webcam: Weather and instrument monitoring Automatic Weather Station

  43. MRR Ze from new algorithm of Maahn et al. 2012: can detect virga (sensitivity down to -14 dBZ) Ice clouds with virga case at PE, E Antarctica Webcam 2012-02-20 16 UTC Ceilometer : attenuated backscatter 20 Feb 2012 I. Gorodetskaya, KULeuven

  44. MRR Ze (from -14 dBZ), W, spectral width from new algorithm of Maahn et al. 2012: Snowfall followed by virga case at PE, E Antarctica Webcam 2012-02-28 14UTC Ceilometer : attenuated backscatter 28 Feb 2012 I. Gorodetskaya, KULeuven

  45. Liquid-containing clouds are detected with threshold βatt > 102.8 x 10-9 sr-1 m-1 determined using cloud structure + LWin Mixed-phase cloudscases at PE, E Antarctica Ceilometer : 7 Feb 2012 Webcam 2012-02-07 04:39UTC Ceilometer : 8 Mar 2010 Ceilometer : 17 Mar 2010 I. Gorodetskaya, KULeuven

  46. Cloud effects on radiative fluxes using simultaneous measurements Cloud SW forcing(all vs mixed phase): Cloud LW forcing (all vs mixed phase): I. Gorodetskaya, KULeuven

  47. 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)

  48. In Situ (Covered in Topic 8?) Maturing Sensors (Anything new since 2010?) CVI + SP2 CVI + ATOFMS CVI + AMS CFDC (Introduced 1996) New Sensors (Anything new?) SPIN ISI

  49. Deployed inlets for the extraction of ice nuclei: Addressed question: Study the physico-chemical characteristics of atmospheric ice nuclei in mixed-phase clouds under ambient conditions as a function of air mass origin and as a function of cloud type and cloud properties. CLACE2013 : Intensive measurement campaign (Jan-Feb 2013) at the high alpine site Jungfraujoch in the Swiss Alps Participating groups: Ice-CVI from TROPOS ISI from PSI

More Related