Observational study on melting layer characteristics over Palau in Pacific Ocean

1.So far there is no extensive study of bright band height is carried out over oceanic region.2.For the first time, long term observations using Wind Profiler Radar and Automatic Weather Station along with TRMM and Radiosonde measurements have been carried out to understand the bright band height over Palau islands.3.Monthly and seasonal variations of bright band height has been analyzed using fairly continuous data for four years.4.In addition, the effect of El Nino on bright band height has been studied.

In this paper, four years (April, 2003–March, 2007) of wind profiler radar (WPR) observations, Tropical Rainfall Measuring Mission measurements, radiosonde and automatic weather station data are utilized to characterize melting layer/bright band (caused due to the melting of hydrometeors when the precipitation has a significant stratiform cloud contribution) variability during easterly and westerly monsoon periods over Palau in Western Pacific Ocean. Four years observational results show that presence of stratiform precipitation is more in Westerly monsoon compared to Easterly monsoon. However, bright band height (BBH) is lower in Westerly monsoon. It is also observed that the BBH during the year 2006 is higher than 2005 possibly due to El Nino effect.