CHAPEL HILL, NC, February 19, 2008 – Information about the atmosphere above the ground is severely lacking across North Carolina. This information, such as the temperature of the air and the type of precipitation falling aloft, is critical to short-term forecasts during hazardous weather events such as ice storms.
Precipitation can reach the ground in many different forms, including rain, freezing rain, drizzle, snow, sleet, and hail. In order to plan an accurate response to a weather event, it is crucial to know what kind of weather event is in the works. Heavy rain could mean flooding; whereas, freezing rain, ice or snow could make roads slippery, dangerous and impassable. Snow and ice also bring the added hazards of falling trees, downed power lines and power outages. Ice storms can result in massive power outages, disruptions to everyday life because of the lack of power, and road closures.
To better assist North Carolina meteorologists and emergency managers, RENCI is working to make it easier to determine the type of precipitation a weather event will bring. Its main tool: the Micro Rain Radar, or MRR. RENCI is one of the first U.S.-based organizations to use this German-built weather prediction technology.
The MRR is a compact, vertically pointed radar that calculates and provides the rain rate, liquid water content, reflectivity, and the vertical fall velocity of precipitation in real time. The radar detects precipitation in the atmosphere and how high above the ground that precipitation will remain frozen before beginning to melt — the freezing line. Above the freezing line, precipitation is frozen, and how close to the surface that line is determines whether precipitation falls as rain, freezing rain, sleet or snow. The radar also can be used to accurately predict rain rates—how fast rain is falling—during severe storms. The radar system consists of an antenna dish, transmitting and receiving unit, and a data transmission interface.
“The MRR is providing real-time, upper air data about precipitation that is not otherwise available during hazardous events such as ice storms,” said Jessica Proud, RENCI meteorologist. “Used in conjunction with other observations we think the MRR is an extremely useful resource for forecasters making a short-term forecast.”
Currently, RENCI has its mobile MRR stationed at a facility in Chapel Hill, where it is continuously collecting weather data along with two other instruments RENCI is testing, including a weather station and laser disdrometer, an instrument used to measure the drop size distribution and velocity of falling precipitation. The MRR sends its data in real time to a RENCI website, (mmrr.renci.org), that posts the data from the MRR, weather station and disdrometer. The web page is updated every few minutes with new data. This data is available for forecasters and researchers to use both during events for short-term forecasting and after events for case studies that assess the utility of the data.
To date, the MRR data has provided information on three winter weather events and several rain events at various North Carolina locations. The MRR unit will remain at its Chapel Hill location. If a winter storm is predicted outside the Chapel Hill area, it will be transported to that area to collect storm data.
Once a full winter’s worth of data is collected and analyzed and research is complete, RENCI will collaborate with emergency managers, power company officials, and others on how to best use the MRR. RENCI envisions developing and deploying a network of MMRs to assist the state of North Carolina in disaster planning, mitigation, and response.
RENCI…Catalyst for Innovation
The Renaissance Computing Institute brings together computer and discipline scientists, artists, humanists, industry leaders, entrepreneurs, state leaders and educators for collaborations designed to reshape science, the economy, the state of North Carolina and the world. RENCI leverages its expertise and resources in leading edge computing, networking and data technologies to ignite innovation and find solutions to previously intractable problems. Founded in 2004 as a major collaborative venture of Duke University, North Carolina State University, the University of North Carolina at Chapel Hill and the state of North Carolina, RENCI is a statewide virtual organization. For more, see www.renci.org.