GENERAL INFORMATION > >1. Principal Investigator: Dr. C. Martin Platt. However, I will not be at the IOP. The radiometer has been requested by Dr. Wynn Eberhard, to operate with his lidar. > >2. Institution: CSIRO, Division of Atmospheric Research, P.Bag 1 Aspendale, VIC 3195 Australia > >3. Instrument (include brief physical description and > explain function): Narrow - beam infrared filter cloud radiometer. The radiometer is contained in a metal box about 18 in by 18 in by 12 in. It is freestanding on the ground. The radiometer has Newtonian optics, three narrow-band filters to cover the atmospheric window, and a liquid-nitrogen cooled detector. The radiometer is fast, with a response time of one second to detect rapid changes in radiance from clouds. The minimum detectable temeperature is about 0.1 degree C, and the radiometer can measure background sky brightness temperatures down to -80 deg C. The function of the radiometer is to measure the cloud radiance as the cloud passes over in the zenith. It is used in conjunction with an infrared or visible lidar from which cloud height, structure and cloud infrared emittance and optical depth can be obtained at one of three selectable wavelength intervals of width 1 micron. NOTE: The radiometer operated in the 1995 spring IOP. Requirements are identical to last year. > >4. a. Brief statement of work including objectives, > approach, and requisite atmospheric conditions: The radiometer will be used in conjunction with Dr. Eberhard's lidar, and possibly Dr. Sassen's lidar, to obtain cloud radiance simultaneously to the measurement of cloud backscatter profiles from the lidar. Using these two measurements, together with radiosonde data of temeprature and humidity, and water vapour data from a microwave radiometer, information can be retrieved on cloud height and structure, infrared and visible optical depth, phase, together with some information on cloud particle size and crystal habit.The retrieved data will be compared with spectra from the AERI data, to compare accuracies and to further inhance the available information. It is proposed to integrate this Lidar/Radiometer(LIRAD) method into a semi-automated system as soon as is feasible, for use at CART sites. The approach is to operate the radiometer continuously during observations, noting the times that the lidar measures backscatter profiles. The radiometer output is fed to a PC, with requisite software, to display and store the raw data as it is acquired. The radiometer needs to be calibrated every hour against liquid nitrogen source and a near-ambient source. These are supplied in the requisite dewars and the radiometer proceeds through a programmed calibration cycle on request by use of a rotating 45 degree plane mirror. IT IS ESSENTIAL TO CALIBRATE THE RADIOMETER REGULARLY TO OBTAIN OPTIMUM ACCURACY. > > b. Is the information to be gathered during the IOP for > the support of an ARM Instrument Development Program > (IDP) project? Yes. As well as supplying scientific data, the radiometer was constructed at CSIRO under an IDP. A Mark II instrument with a Stirling cycle cooler has been developed. This model is intended for eventual permanent deployment, if accepted. Thus the MARK I will be used to further supply data to demonstrate the potential of such an instrument in the context of ARM. > > c. If the answer to 4.c. is yes, identify the CART > instrument and the specific objectives of the work > with regard to producing the CART instrument. I think I have answered this in 4b. > > >5. Date of arrival at ARM Southern Great Plains CART site: >Start of April-first week >6. Dates of operation: >Please consult with Wynn Eberhard. It will cover his dates. >7. Hours of operation: >During IOP campaign hours. That is, it is not expected to run continuously day and night. >8. Date of departure: >Consult Wynn >9. Names of personnel who will be working at the site: >Consult Wynn Eberhard >10. Requested instrument location (near central facility, > etc.): >Close to Wynn's lidar. Preferably also close to Jim Spinhirne's micropulse lidar, and Ken Sassen's lidar(?). >11. Site Support > > a. Will you request assistance of the CART site staff > during deployment or operations? Please consult Wynn Eberhard. There will need to be someone to regularly calibrate radiometer during experimental runs. > If yes: >See 11a > (1) Estimate the number of man-hours requested: If someone has to calibrate the radiometer, this will take approximately 5 minutes every hour during runs > > (2) Will the CART staff require special training? They will need to be shown how to fill the dewars( This is unless Wynn Eberhard can provide the necessary personpower support). The liquid nitrogen dewar requires special attention to avoid draughts across the dewar causing ice fog above the liquid. This fog takes several minutes to disperse. Training is not very technically difficult, but neceassary to observe certain procedures. > > If yes, explain. See above > > (3) Is an operating procedure available for CART > site evaluation and use? I sent Jeff Griffin one last year. > > If yes, please provide us with a copy. >I can make up another one if necessary > > b. Will you need assistance with on-site delivery or > unloading, e.g., access to a forklift, etc.? >No > c. Will you need on-site transportation? >Please ask Wynn Eberhard > > d. Will you need on-site communications? >Ask Wynn Eberhard > Voice? >Ditto > Data? >YEs. >Microwave water vapour path. Radiosonde temperature and humidity. >12. Facility Requests > > a. Dimensions of instrument, equipment and shelter: >Similar to last year. There was an enclosed box available for spring 1995 IOP > b. Additional space required for access, support > facilities, vehicles, etc.: None I dont think > > c. Requests for the the setting, e.g., grade, > vegetation, concrete support pad, etc.: >Level support for enclosure. > d. Access requirements (vehicle or pedestrian, > frequency): >Pedestrian access evry hour or so. > e. Shelter request for instrument, equipment, > personnel: >Shelter should be available from last year. See 12a. >13. Equipment Requested > > a. Routine Tools: > b. Special Tools: > c. Electronic parts: > d. Diagnostic or test equipment: > e. Simple hardware: > f. Simple building material: > g. Laboratory material: > h. Other: >a - h above. Should not need any. >14. Expendables Requested > > a. Specialty gases: Liquid nitrogen. About 2 litres evry three hours only during experimental runs. > b. Solvents: > c. Reagents: > d. Cleaning materials: soft brushes and tissues to clean mirrors > e. Balloons: > f. Stationery supplies: > g. Other: > >15. Utilities Requested > > a. Power: > > Source and number of circuits? >Normal 110 volt outlet > Voltage and total amperage? >110 volts, 2 amps > Single Phase? 3-Phase? >single > b. Water: >Possible 2 litres water per 3 hrs. plus blocks of ice-fridge size > c. Sewage and waste disposal: Water > >16. Interference and susceptibility to Interference (include > information on power output and frequency > > a. Electronic: > b. Electromagnetic: > e. Acoustic: >We have had not had any trouble at the site previuosly >17. Safety Issues > > a. Does this equipment emit microwave radiation? No > > b. Does this equipment emit acoustic energy? > Frequency range: >No > c. Does this equipment emit laser energy? >No > > d. Hazardous materials used, e.g., toxic materials, > compressed gases, cryogens, etc. (Material Safety > Data Sheets are required.) >Liquid nitrogen poured periodically into detector dewar and calibration dewar fro accessory dewar > Quantity to be stored at the site: Will use available supply > How will hazardous materials be stored? See 17d above > How will materials be installed into the equipment? see 17d > How will excess material be disposed of? >Usual methods > e. Specify the waste generated by the operation of the > equipment >None > > f. Will work be performed at an elevated area or > confined space? I dont think so. As for last year. Please consult W.Eberhard > > > g. Will safety equipment be properly maintained and > deployed (yes, no, or n/a)? n/a > > h. Are there any other known safety issues and/or > requirements? No > >18. Do you have weather support requirements? > > a. Weather forecast support for operations > > (1) List specific cloud, precipitation, etc. > conditions that must be known in order to make > operational decisions or that could favorably > or adversly impact your experiment. > > (2) What is the desired forecast lead time for > each of the conditions listed in (1)? Consult W.Eberhard > > b. Weather warning support requirements > > (1) List specific conditions that could cause > safety hazards for your operations, e.g., > lightning, high winds, etc: > > (2) Desired weather warning lead time: Consult with W. Eberhard > >19. If you have any other support requirements that have not > been addressed by questions 1 - 19, please explain them > here: > > >YOUR DATA CONTRIBUTIONS TO ARM > >20. List the atmospheric data that you will release to the > ARM Science Team (through the ARM Experiment Center and > Data Archive) and the estimated availability date (months > after IOP) for each of these data. Vertical atmospheric radiance in a spectral interval of 1 micron in the atmospheric window during experimental runs. Available in 6 months after experiment > >21. For each of the data types that your listed in item 21, > please provide information on the following data > attributes, as applicable: > > a. Units Watts/m2/sr > b. Accuracy (proximity to true value) +or - 0.1 deg C. > c. Precision (repeatability, reciprocal of sample > variance) 0.2 deg C > d. Range of acceptable values. Values of what? Radiometer is linear between -80 and 40 deg C. > e. Temporal resolution (temporal representativeness of > observation). 1 second > f. Temporal reporting interval (time interval between > successive > observations).1 second > g. Vertical resolution n/a > h. Vertical range (minimum and maximum) n/a. Radiometer will detect any clouds in the troposphere, including very thin, cold cirrus. > i. Vertical coordinate (meters above mean sea level, > millibars, etc.) n/a > j. Horizontal resolution Depends on wind speed at cloud height. > k. Horizontal range (minimum and maximum) n/a > l. Horizontal coordinate (UTM, lat/long, etc.)n/a > m. Angular resolution 6 to 10 milliradians > n. Angular spacing n/a > o. Spectral resolution Filter width is approx 1 micron. > p. Spectral range. Three wavelengths at 8.6, 10.6 and 12.4 microns centre > >22. What data format do you plan to use? Data is stored on PC disc > >23. Provide an estimate of the data volume, itemized by > observation: low volume rate > > >YOUR DATA REQUIREMENTS FROM ARM > >24. List the in situ quantities you require for comparison > with your instrument data. >Periodical radiosonde profiles of temperature and humidity to highest level attained. Preferably to about 20 km. Screen temperature and humidity >25. List the additional in situ quantities you require (see > note below): > >26. List the remotely sensed quantities you require for > comparison with your instrument data: >Continuous data of liquid water path from microwave data AERI spectra over selected intervals-post IOP Micropulse lidar data >27. List the additional remotely sensed quantities you > require (see note below): Consult with Wynn Eberhard and Ken Sassen. They wish to use the radiometer data for comparison with their lidar data. > >Note: These additional quantities might be needed to >diagnose discrepancies between remote sensor and in situ >observations, or to calibrate/tune algorithms used to derive >data streams from remote sensor output. >