Middle Atmosphere Program. Handbook for MAP. Volume 30: International School on Atmospheric Radar

Broad, tutorial coverage is given to the technical and scientific aspects of mesosphere stratosphere troposphere (MST) meteorological radar systems. Control issues, signal processing, atmospheric waves, the historical aspects of radar atmospheric dynamics, incoherent scatter radars, radar echoes, radar targets, and gravity waves are among the topics covered

On the Frequency and Altitude Resolutions in Incoherent-Scatter-Radar Measurements

Systematic distortions of the spectrum of the signal scattered from diffusive media, and limitations on the resolutions in frequency and altitude due to the finite receiver bandwidth and the finite transmitted-pulse duration are estimated, using the radar-ambiguity function. The requirements for frequency and altitude resolutions are incompatible in the filter-bank method (FBM) which directly measures the power spectrum. With the actual parameters of the ionosphere, the FBM is shown to be inconvenient for pulse radar measurements except those of higher altitudes and/or with higher radar frequencies. In the correlation-function method (CFM) which calculates the cross-correlation or autocorrelation function, the resolutions are independently determined in frequency and altitude. The pulse duration is concerned only with the resolution in altitude. The minimum duration is limited by the sensitivity of the radar system, while the maximum is limited by the characteristic time of fluctuations in the medium which scatter the radio waves. Various methods for measuring the autocorrelation function are also described

Relationship between Wind and Precipitation Observed with a UHF Radar, GPS Rawinsondes and Surface Meteorological Instruments at Kototabang, West Sumatera during September-October 1998

Simultaneous observations with a UHF-band boundary layer radar (hereafter referred as BLR), GPS rawinsondes and a tipping-bucket-type rain gauge were conducted at Kototabang (0.20 S, 100.32 E, 865 m MSL), which is located on the mountainous region near Bukittinggi, West Sumatera Province, during 27 September–7 October 1998 (rainy season). Low-level (1–3 km) westerly wind stronger than 10 m/s was observed, and precipitation tended to occur when the low-level westerly wind became weak (2–5 October). Similar relationship was observed for two months (1 September–31 October 1998) during which only BLR and surface meteorological instruments were operated at Kototabang. NCEP/NCAR objective analysis, and GMS TBB data showed that the low-level (850 hPa) wind field, and cloud distribution, were both completely different between the Indonesian Archipelago (east of Kototabang) and the eastern Indian Ocean—including the Bay of Bengal (west of Kototabang)—during the analysis period. Two large-scale cloud disturbances existed along the equator in the western side (80 –100 E), but precipitation at Kototabang did not correspond to these cloud disturbances. The implication is that effects of the mountain range of Sumatera blocked the large-scale cloud disturbances over the Indian Ocean. The precipitation by local-scale cloud systems prevailed at Kototabang. The convergences of local circulations, which are generally dominant under weak background winds, are considered as the major cause of local-scale cloud systems

ジリョクセン ノ サイケツゴウ ニ ヨル プラズマ ノ カソク オヨビ カネツ ニ カンスル ケンキュウ

京都大学0048新制・論文博士工学博士乙第2642号論工博第726号新制||工||292(附属図書館)UT51-49-L319(主査)教授 木村 磐根, 教授 宇尾 光治, 教授 板谷 良平, 教授 加藤 進学位規則第5条第2項該当Kyoto UniversityDFA