Assimilation of Wind Profiler Data in the Canadian Meteorological Centre’s Analysis Systems

Abstract

Real-time horizontal wind observations from the National Oceanic and Atmospheric Administration's (NOAA's) Profiler Network (NPN) are assessed in preparation for their assimilation in the Canadian Meteorological Centre (CMC) analysis systems. As a first step, radiosonde winds from 20 stations were compared to the central U.S. profiler stations over the 2001/02 winter season. It was found that profilers are at least as good as conventional radiosonde data. The 2001/02 winter season data were also used to examine the vertical correlation structure of the observation error for profilers. Using a statistical analysis of innovations, the observation error standard deviation of the wind components is estimated as 2.2 m s Ϫ1 and the vertical correlation length is approximately 500 m. These results suggest that the data are vertically correlated because they are available every 250 m. Therefore, a thinning process is proposed in which one out of three data are selected in the vertical for each station.

The impact of radiosonde data over the ice‐free Arctic Ocean on the atmospheric circulation in the Northern Hemisphere

“…For weather balloons (referred to as ADPUPA in NCEP system), the data at 1000, 925, 850, 700, 500, 400, 300, 250, 200, 150, 100, 70, 50, and 10 hPa are used. Reports from aircraft and satellite retrievals are reduced to every fourth value and wind profilers to every third level [ St‐James and Laroch , ]. National Oceanic and Atmospheric Administration (NOAA) daily 1/4° Optimum Interpolation Sea Surface Temperature (OISST) version 2 [ Reynolds et al ., is used to provide the ocean and ice boundary conditions.…”

Impact study with observations assimilated over North America and the North Pacific Ocean on the MSC global forecast system. Part I: Contribution of radiosonde, aircraft and satellite data

“…In the first experiment, denoted NO_RaOb, radiosonde (tEmP, PILOt and dropsondes reports) and wind profiler data are denied over North america. although the radiosonde stations and the NOaa wind profilers are distinct networks, we grouped them because the value of the wind profiler network in the mSC forecast systems has recently been evaluated (St-James and Laroche, 2005). It was shown that wind profilers, mainly located in the central united States and alaska, provide only a slight improvement, especially at short forecast ranges.…”

Ground-based remote sensing profiling and numerical weather prediction model to manage nuclear power plants meteorological surveillance in Switzerland

“…The core of this system is the fully compressible non-hydrostatic model developed by COSMO (the Consortium for Small-Scale Modelling, currently composed of the national weather services of Germany, Switzerland, Italy, Greece, Poland, Romania and Russia -see http:// www.cosmo-model.org/. The COSMO model includes a full set of physical parameterizations suited for weather prediction applications (Steppeler et al, 2003). The Newtonian relaxation technique known as nudging (Schraff, 1997) is used to produce the initial conditions for each forecast; although simple, this method is an efficient way to nudge the state of the model towards the real state of the atmosphere.…”