Latest Status Reports

TDF Developments Funded in FY 2007

Overview of How TDF Development Priorities have been Established

During the past two years, development priorities in the Earth Observing Laboratory (EOL) have been established using a multifaceted approach. Initial development ideas have originated from multiple sources, including: NSF  program managers; the NSF User and Facilities Assessment Workshops; the external advisory committee to EOL; EOL facility managers; the development advisory committee (DAC), a committee comprised of representatives from each EOL facility; and from EOL, NCAR, and external colleagues. Once formulated, the development ideas have been vetted using a multistep process based upon the following selection criteria: scientific/engineering need and merit; benefits to the community; engineering risks; constraints (budgetary, personal, and scheduling); and fit with EOL and NCAR’s strategic plans. The process for small emerging seed projects with budgets less than 10k are less involved, but still require a review process. After consideration of budgets and the various selection criteria, TDF in consultation with the EOL Management Advisory Committee (MAC) make final decisions on which development projects to support. For the next round when new development proposals are considered (perhaps in FY 2009), a greater emphasis up front will be placed on development proposals falling within central themes identified by EOL management.

1.  Lidar Wind Profiler

This effort, which began in Jan. 2007, explores the possibility  of utilizing EOL's Raman Shifted Eye Safe Aerosol (REAL)  Lidar to measure winds and possibly turbulence using a rotating wedge. Such a system potentially offers better time resolution, altitude resolution while reducing the effects of clutter (such as signals from the ground, birds, etc.) and interference from radio waves than is possible from current radar wind profilers and SODAR systems. 

• Status: This project has gotten off to a slow start for several reasons: personnel obligations to other projects; changing design; and the need to first analyze CHATS data to better understand the required  sensitivity.  Based on the CHATS data there is now much more confidence that this demonstration project will yield improved results over existing technologies. The critical optical wedges have been ordered and the control software will be developed over the summer. The field demonstrations are planned for this fall.

2.  CAMS Instrument for the G-V

EOL began development of the Compact Atmospheric Multi-species Spectrometer (CAMS) for the G-V in FY 2007. This new instrument will rely on the same state-of-the-art advancements employing difference frequency generation  (DFG) technology as other EOL airborne infrared absorption spectrometers, but with major upgrades and innovations for operation on the G-V platform. It is one of many important trace gas chemistry instruments being developed for the NSF/NCAR G-V for a proposed  DC-3 study (Deep Clouds, Convection & Chemistry) as well as other airborne studies in the upper troposphere/lower stratosphere. This new instrument is being specifically developed for detection of formaldehyde and potentially other trace gases such as methanol, acetylene, ethylene, formic acid, and/or ethanol.

• Status:   Much progress has been achieved, including: the second phase testing of a new waveguide design by NTT Photonics, which may be included in the final HIAPER instrument; continued Object Oriented LabView software development, which will be used on the GV instrument as well as other instrument platforms; implementation of new diagnostic software as well as a new more powerful acquisition system as a backup and a test bench for proof of concept experiments in multispecies measurements; and further airborne DFG studies on the NASA DC-8 during the ARCTAS field study. The latter was extremely important in providing additional input on DFG system design criteria during actual airborne studies, and the engineering lessons learned are now being incorporated into the G-V HIAPER design. The ARCTAS measurements, furthermore, are also highlighting the tremendous potential of DFG technology for unattended airborne trace gas measurements of the future. 
  

3.  NO/NOy for the G-V

In FY 07 EOL funded the completion of this instrument for measuring NO and NOy (the sum of various gas phase nitrogen oxide species) on the G-V. This instrument will be used in many chemistry campaigns, including the proposed DC-3 experiment.  A version of this instrument has recently flown on the NASA WB-57 during the TC4 study and a serious problem discovered in that study is now being corrected.

• Status: The modified instrument worked very well on the G-V during START-08 and the project is now completed.  During this process a number of modifications were implemented, including: replacement of spectral filters; the instrument was re-built using certified foam insulation; the data acquisition system was completed; the containment vessel was assembled, tested, and installed; new interconnect cables were made; and a modified HIMIL inlet was fabricated and installed.
  

4.  Development of a plan for long-wave radiation for the G-V

In our efforts to continually produce state of the art observing technology, EOL staff is leading a development effort for an instrument to measure long-wave radiation emitted by the earth's surface from the G-V platform. Measurements of terrestrial emissions are an essential element in understanding the earth's radiative budget. Personnel in EOL are conducting surveys to define community needs for such instrumentation and devise a plan to improve upon what currently exists. Ultimately, this will lead to the development of new G-V instrument with this important capability.

• Status: The instruments needs have largely been defined and present work focuses on defining preliminary specifications for such an instrument based upon a survey of users and developers of airborne radiometers. Two vendors have been contacted along with two users of instruments from these vendors who have modified the instruments for airborne operation. The sensor modifications and associated performance are currently being assessed before moving on to the third and final phase, developing an implementation plan. Survey results are presently coming in and a written summary with future project plans will be prepared by the end of the calender year.

5.   SATCOM software products for the G-V

In F07 EOL started gathering input from the NCAR/NSF user community about what products they desire relative to  what is currently available in regards to Satcom software products.  This project has been discussed at inter-agency working groups, but owing to difficulties in coordinating field schedules in FY 2007, no workshop other than that at the NSF-User Workshop in September was planned. A breakout session at this workshop was held, and many technical people (~ 15 - 20) with few users attended. A number of workshop suggestions were received just as the HIAPER hardware issues were being solved (increased bandwidth and solved Iridium issues). 

• Status:  This project has been completed and based upon some limited feedback during the User Workshop the following recommendations have been implemented: 1) explicit wording in the Facility Request Form has been added indicating what is offered at no cost and what will cost more; and 2) an effort has begun to make more reliable what is offered. The third thrust, implementing collaborative software (video conferencing, shared display in flight planning mode, etc.) has not been pushed due to a lack of time caused by extensive field commitments.    planning mode, etc.) are being considered. After receipt of a final report this year, this project will be completed.

6.   Water Vapor  Reference Sounding System

This collaboration between NSF/EOL and South West Sciences Incorporated (SWI) is aimed at exploring the feasibility of balloon-borne tunable diode laser (TDL) technology for in-situ water vapor measurements with verifiable accuracy. Such measurements are badly needed by the climate community.

• Status: This project has recently started and progress is being made in developing an implementation plan for a yearlong test of two SWI  tunable diode laser (TDL) instruments in the laboratory. Specifically, these two instruments will be challenged with known water vapor mixing ratios at pressures and temperatures indicative of conditions spanning altitudes from the surface to ~ 30 km at periodic intervals over a yearlong time period. The retrieved water vapor mixing ratios will be compared to the known input values (measured with a NIST traceable dew point hygrometer) to assess accuracy and long term stability of both instruments. The results will be assessed and a determination where the project will go will be made at the end of the yearlong test period. 

7.    Meteorological Satellite Data Collection and Processing

Funding was provided to improve satellite imager and sounder data collection and processing capabilities. This objective was completed at the end of the 2006 calendar year.

• Status: As indicated, the core project has been completed. A second thrust, which was not part of this project, involves collection of feedback from the broader scientific community with regard to future needs for satellite products and services. This activity has been taken over by a broader NCAR/UCAR committee, but to date progress has been slow.  

8.  WISARD: Wireless Integrated Sensor ARray Demonstration

In contrast to the other 7 development efforts funded this past year, the WISARD effort represents the first small emerging investigative request (requests with a total cost under 10k) designed for small exploratory projects and feasibility studies. Accordingly, the selection process for such studies is significantly less rigorous than the regular TDF proposal effort. The WISARD effort seeks to demonstrate the viability of a next-generation near-surface facility that would wirelessly network a multi-disciplinary array of off-the-grid sensors on a highly portable, readily deployable tower.  Following this proof-of-concept (Phase I) and subsequent input from the geoscientific community (through a survey) a Phase II TDF proposal would be pursued.

• Status: A small amount of funds have been spent on the telescoping tower system. Other than this, the project is going at a slow pace due to other commitments with tight time schedules. The PI indicates that progress this year will pick up.

   

9. HOLODEC: Holographic Detector for Clouds

This development is the second small emerging seed project funded by TDL. The HOLODEC development is an aircraft instrument designed to obtain a 2-D profile, 2-D size and 3-D position of cloud particles in the size range of around 15 microns to 1 mm using digital holography. This type of instrument fills an important size measurement gap between instruments that size and count cloud particles by scattering (particles in the size range of 1 to 50 microns) and instruments that do the same by imaging (particles in the size range of > 100 microns). Further, it is uniquely able to detect shattering of ice crystals on leading parts of probe housing, because it can detect the 3-D clustering of shards of shattered particles in the sample volume. This is important as it allows us to estimate how much other instruments overestimate cloud particle densities due to counting shards of shattered particles.

• Status: Additional funds were also provided by the EOL Director’s Office and the RAF to get the project started and critical long lead-time components (laser and camera) have been ordered. These funds constitute ~ 40 to 50% of those needed for completion. The project is on schedule and a design review will be forthcoming.
  

Other Development Efforts Not Funded by FY 2007 TDF Funds

High Precision carbon dioxide isotopic ratio instrument

This long-standing development project that began in FY 2002 with NSF Biocomplexity Special Funds progressed rapidly in FY 2007. This instrument will provide continuous (seconds to minutes time resolution) high precision measurements of ¹³CO₂ to ¹²CO₂ using a new infrared spectroscopic instrument utilizing the same DFG technology as the airborne CAMS instrument. This will augment more traditional measurements of this ratio from high precision isotopic ratio mass spectrometry, leading to an enhanced understanding of the carbon cycle.  The present precision of ~ 0.3 per mil achieved in ~ 2 minutes is close to the design goal of 0.1 per mil. However, a number of noise source sources discovered in 2007, when properly addressed, promises to  reduce this precision by an order of magnitude. Such performance would make this technique directly competitive with the immobile mass spectrometric approach.

Extensive laboratory testing will continue on this instrument throughout 2008 in an effort to eliminate the identified noise sources and this will be followed by an extensive effort to assure measurement accuracy. Field-testing, including side-by-side sampling with an isotopic ratio mass spectrometer, is anticipated near the end of FY 2008.

Development of a high efficiency waveguide DFG instrument

With partial support from the NCAR Director's Opportunity Fund in 2006, TDF personnel have been working with Japanese scientists and engineers from the NTT Photonics Laboratory, NTT Corporation in developing and assessing a new high performance optical frequency conversion technology based upon wave-guide DFG devices. This group published a paper on the first phase of this instrument development and assessment in FY 2007.

A second phase study using an improved device based upon EOL input has been tested and the results look very promising. A new paper describing these results will be forthcoming and plans for a third phase with additional device improvements are being formulated. Ultimately, it is anticipated that these efforts will lead to DFG devices with significantly improved performance, both in terms of higher output powers and conversion efficiencies. If successful, this will open up many new detection methods for instruments on the G-V.