First Look at the Upper Air Data Continuity Study High Resolution Flight Analysis

In 2012, the National Weather Service began a Data Continuity Study (DCS) comparing the legacy Upper Air System (MicroART) and the new Radiosonde Replacement System (RRS). NWS directive NDSPD 10-2101 required this test be conducted due to the improved radiosonde sensor technology associated with the radiosonde replacement system as the legacy system is phased out of the network. This study will be used to assist in determining what component of the total change seen in the climatic data is a result of true atmospheric changes and what component is related to a change in sensor technology, algorithm changes, and new procedures.

The NWS plans to meet the goals of this test early in 2014 by completing test flights at up to four upper air stations representing diverse meteorological and climatological conditions. The stations chosen were: Sterling VA, Caribou, ME, Barrow, AK, and Barrigada, Guam. At these locations the MicroART and the new RRS instruments were flown in tandem, twice per week, during standard synoptic observation times. Each site had the goal to achieve 120 flights reaching a minimum height of 30 hPa over a period of 70 weeks, barring supply and budget constraints. After each flight, all of the data was archived to the National Climatic Data Center (NCDC) for analysis. In addition, the Sterling Field Support Center (SFSC) in Sterling, VA had the ability to record and analyze higher resolution flight data in addition to the coded messages. The analysis of the high resolution data allows for a more in depth comparison of the pressure, temperature, relative humidity, and height differences between the two different radiosondes. This paper will discuss the procedures used to collect and analyze the DCS flight data with the results.