Zeinab Sayed Fahmy

1. Developments of upper air Sounding System in Egypt by Zeinab Sayed Fahmy Programmin manger in Upper Air Stations Egyptian Meteorological Authority (EMA) Koubry ELQuobba EMA , Cairo , Egypt , P. BOX : 11784 Fax : 00202 226852789 zanb_f@hotmail.com Vaisala GPS station

2. Comarison between RDF/GPS Vaisala and Modem of upper air sounding system Global Positioning System (GPS) GPS Signal Path • There are two system in upper air stations • 1-Upper Air sounding system SR2K2 Modem • consists in collecting P,T,U, and wind finding data measured and transmitted from a Radiosonde M2K2-DCduring its flight through upper atmosphere layers which used M2K2-DC (Dual Core) GPSonde that is already widespread in the operational SYNOP upper-air network of major and National Met. Services. • M2K2 GPSonde successfully participated to the latest WMO inter-comparison of High-Quality Radiosondes, Designation of High-Quality Radiosonde is fully applicable to MODEM’s M2K2 GPSonde • 2-The DigiCORA® Sounding System MW31 with the Radiotheodolite RT20A and GPS wind finding ( Vaisala ) contains :- • A-Radiotheodolite RT20 system • Radiotheodolite windfinding is best suited for situations where the balloon elevations remain above about 16°, so we using the stations of Radiotheodolites in the summer season . • B-GPS wind finding system • portable system with small antennas for 403 MHz telemetry and GPS wind finding RS92-SGP Radiosonde for GPS wind Technology, Major Features All-digital code-correlating GPS Radiosonde Higher level of PTU measurement performance Continuously available, highly accurate wind data code correlating GPS . 2

3. Comarison between RDF/GPS Vaisala and Modem of upper air sounding system fig(1) fig(2) fig(3) fig(4) fig(5) fig(6) fig(7) We compare between the two upper air systems vaisala and Modem :- In the fig (1), (2) and (3) we used system of Modem of upper air sounding system in the 14 jun 2010 we used Modem system and in the fig (4),(5) and (6) the day of 14 jul 2010 we used Vaisala system this data for Marsa matroh ,Asswan, and Helwan stations . In the fig (7) it the statistics for data of max height of wind speed from( Dec 2007 to Feb 2008 ) with using vaisala upper air sounding system we found the data of wind speed and direction for all observations reach to about (30-20) kms . 2

4. Comarison between RDF/GPS systems • Asswan station in Egypt it is one of The Upper-air Network (GUAN) which consists of stations selected from the Global Observing System of the World Weather Watch. Criteria for choice of sites included homogeneity, a history of high quality observations . • The data flow for the GUAN begins with national centers that collect and submit the data to the international system. • The data collected by the network of GUAN stations are transmitted on the GTS in the form of upper-air reports (TEMP and CLIMAT TEMP). • International centers perform quality control on the data, prepare data products for users, and archive it for future users. Some of these international centers prepare routine reports on the performance of the system. • Summary Of GUAN for Asswan Station Range time WMO STATION OBS LVLS 00Z 12Z AVGPRS >100 >50 >10 TEMPS DPDS WINDS (2007 /8 ) 62414 ASSWAN, EGYPT 30 1780 30 0 52.9 27 27 0 1075 630 1157 ( Air upper air st.) (2008 /8) 62414 ASSWAN, EGYPT 28 2097 28 0 26.2 27 26 0 1129 693 1410 ( vaisala upper air st.) (2009 /9) 62414 ASSWAN, EGYPT 29 2541 29 0 16.8 28 28 4 1225 770 1817 ( vaisala upper air st.) (2009/11-4) 62414 ASSWAN, EGYPT 179 16893 179 0 23.3 171 166 4 8215 5071 11446 ( vaisala RDF&GPS upper air) (2010 /4) 62414 ASSWAN, EGYPT 30 2914 30 0 22.6 30 27 1 1344 820 2064 ( vaisala RDF upper air st.) • We found that seine using Air sounding system we used 500 kg of Metrological balloon which burst at latitude less than 30 km and • fill with Hydrogen gas by using Sagim system so we found that the number of significant levels for temperature , dew point and wind in • Air system is less than when used Vaisala system for GPs and RDF system . 2