Building Capacity for Coping with Weather and Climate Hazards

To help society cope with weather and climate hazards, decision makers must be made aware of threats and vulnerabilities so that options of mitigation and adaptation can be developed. EOL has contributed to this strategic priority in 2006 by testing out a new radar technique that can give forecasters a new look at one of the more well-known and common weather hazards – thunderstorms – and by transferring its advanced lidar technology to assist homeland security in its efforts to detect dangerous aerosol plumes and even material used to make car bombs.  EOL is also assisting scientists at the Australian Bureau of Meteorology Research Center in Brisbane, Australia, to set up a permanent location of the CP-2 radar.

• REFRACTT [Highlight]
• LIDAR “Standoff” Laser
• REAL for Homeland Security
• CP-2 Radar

Refractivity Experiment For H2O Research And Collaborative operational Technology Transfer (REFRACTT) [Highlight]

EOL scientist Tammy Weckwerth (r) looks over S-Pol data with SOARS Protoge Theresa Aguilar from Texas Tech University during the Refractivity Experiment For H2O Research And Collaborative operational Technology Transfer (REFRACTT). Not only can the research gleaned from REFRACTT data improve precipitation forecasts by enhancing the observed field of water vapor, the experiment was an excellent opportunity for students in atmospheric science to gain hands-on experience with observational datasets.

The REFRACTT experiment was conducted from 5 June through 11 August 2006 in northeastern Colorado in an effort to test a new observing strategy of tracking atmospheric moisture just above Earth's surface to help forecasters pin down the locations where storms might rage a few minutes to a few hours later. EOL scientists were part of a multi-agency team of researchers who collected and analyzed very high resolution measurements of water vapor variability and transport in the convective boundary layer. These data came from the NCAR SPOL-ka, CSU CHILL radar, several GPS receivers and one NCAR MGAUS system.

Up to now, the sparse network of surface weather stations has limited forecasters' ability to map fields of moisture and predict exactly where heavy rains might develop. One of the scientific objectives of REFRACTT was to assess potential improvements these measurements may have in numerical model forecasts of quantitative precipitation. The ultimate, long-term goal is to implement radar refractivity measurements on the national network of operational radars.

Preliminary processing of the entire data set is nearing completion. This preliminary data set will be reviewed for consistency and errors. The Ka band system operated with S-Pol for about three weeks of the 12-week experiment; the Ka radar is still a development system, and special care will be required for analysis of those data. A final data set will then be created using determined corrections, and that final data set will be delivered to the experiment’s PIs. A special study is being undertaken for Zdr calibration and Zdr stability. A full on-line report will be prepared, along with metadata sub-sets to allow future scientists to select periods of data for analysis.

Timeline:

• 15-Oct-06 - All data quality issues known and characterized
• 15-Nov-06 - Final data set completed
• 20-Nov-06 - Final data set available for automatic access through NCAR Mass-Store
• 01-Dec-06 - On-line report and meta data completed

It is expected that the final data set will consist of over 2 TeraBytes of polarimetric radar data and several thousand summary images of those data. Additionally, it is desired to re-engineer the tools required to produce quality-assured fields of radar refractive index, a re-development effort for EOL.

LIDAR “Standoff” Laser

In FY06 EOL constructed and delivered a wavelength converting Raman cell, exactly the same as used in REAL, to the Army Research Labs (ARL) in Maryland. It was integrated into an experimental device designed to breakdown substances at ranges of 10-30 meters. The spectrum of the emission from the breakdown (a small spark) contains signatures of the substance and allows investigators to determine whether the material may be hazardous. The REAL Raman cell is uniquely capable of providing high energy pulses at 1.5 microns, thereby enabling eye-safe energy densities at the ranges ahead of and beyond the focus. This technology may be used to help identify bomb material or biological agents on surfaces from a safe distance.

REAL for Homeland Security

NCAR's Raman-shifted Eye-safe Aerosol Lidar (REAL), developed by EOL scientists, is one of the few lidars that can be used in highly populated areas. The eye-safe and scanning capability expands the lidar's applications to include mapping urban atmospheric pollutants, and studies of dispersion very near the surface of the earth. NCAR's REAL was used in the T-REX field project, while another REAL, built by EOL for ITT, was deployed by the Department of Defense for unattended surveillance of aerosols in Washington, DC.

In November of 2005, ITT Corporation delivered a REAL to the Department of Defense for unattended surveillance of aerosols in Washington DC. The new lidar, built under contract from UCAR, became part of a larger suite of instruments designed to sense chemical, biological, and radiological attacks in the National Capital Region. The REAL will be used to detect and track aerosol plumes. The REAL technology is currently patent pending and UCAR is working with ITT Corp. to establish a tech-transfer licensing agreement for future sales. ITT Corp. has invested in the REAL technology and plans to reduce the size and cost of future units.

CP-2 Radar

The Australian Bureau of Meteorology Research Center (BMRC) is preparing a permanent location for CP-2 in Brisbane Australia. The Brisbane area is an excellent location for studying flash flood producing rainstorms over moderate topography as well as sub-tropical oceanic systems. The S- and X-band portions of CP-2 are on site awaiting setup following the completion of the site in November 2006. EOL is in the process of developing a Piraq based radar processor for use on CP-2.

In October 2006 EOL staff will visit the Brisbane Weather Service to begin training the staff on the uses of a dual wavelength, dual polarization Doppler radar, then from November 2006 to February 2007 they will assist BMRC in the physical setup of CP-2. This will include interfacing the new radar processor and scan control program to CP-2 and assisting with data quality control and calibration. There is considerable work to be done with the potential for many unseen difficulties. The area has a first class array of rain gage and lightning detection. CP-2 will be available for both operational and research activities. During the year proposals for research activities with CP-2 will be investigated.