In this study, the ground condition was discussed in detail on urban area around JR Hakata station in Fukuoka city. Our study area was inundated and covered with silty to sandy sediment due to overflow of the Mikasa river induced by the 2003 Kyushu heavy rain fall on 19th July 2003. Water depth and thickness of the sediment were investigated and their contour maps were compiled. Grain size distribution on 18 sediment samples was analyzed. Direction and speed of the overland flood flow were examined to clarify the ground condition of the area by using all the results.
Ground elevation of inundated areas is lower than that of their surroundings. Main two inundated areas are valley bottom plain of western part of Fukuoka airport, and backmarsh of right and left sides of the river at the back of beach ridge and sand dune. The last one was selected as the study area.
The inundated area, the water depth and the thickness of the sediment at the eastern part of the station were larger than them at the western part of it, since westerly course of the overland flood flow was interrupted by the station and the Kagoshima Main Line. The overland flood water stagnated at the eastern part of the station ran out through only two roads passing under the Kagoshima Main Line. Detailed direction and strength of the overland flood flow were estimated by the result of the sediment analyses.
On the basis of the above results, three areas with unique ground condition were clarified in the study area. These are stagnation area accompanied with fine sediment, deposition area accompanied with coarse sediment, and flow area not accompanied with any sediment. It is clear that the analogical setting of landforms, natural levee, delta, sand splay and backmarsh was developed by urbanization at the study area of once backmarsh.
Consequently, the unique hazard map for flood on urban area at lowland has to be compiled in consideration of the new ground condition yielded by its urban structure.

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Gurgaon is one of the most rapidly developing cities in India. It is located in the southern suburb of the Delhi metropolitan area (DMA). The urban development of Gurgaon is caused by Haryana style, which is unique. The Haryana Urban Development Authority (HUDA) promotes urban developments by private real estate companies and controls them by licensing permission. The system of urban development in Gurgaon and life in the suburbs of Delhi are reported here.
In most Indian cities, urban development is entrusted to each state development authority or housing board. But in Gurgaon, the HUDA entrusts and controls some private companies in urban development by giving development licenses. This shows that the HUDA acts as an agency of urban development. Consequently, urban development in Gurgaon has been achieved at a high speed and on a large scale.
However, some problems have occurred. Because many companies are involved in infrastructure construction, the total investment is inefficient, and the development has increasing disparity. Furthermore, the communities in developed residential areas lack variety. Most of the residents are middle or upper class. Nevertheless, the government has decided to plan a mixed society, and housing in Gurgaon is given to wealthy classes. The residents in housing estates are involved in the carriage trade.
Since economic liberalization in 1991, many households have achieved affluence, and these people desire to live in a rich suburb. However, getting a house in central Delhi is difficult because strict restrictions on development are in place. Because of this, many people have moved out of inner Delhi and chosen Gurgaon as their new home. Consequently, segregation in the metropolitan region is evident.

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Using station rainfall data and ECMWF ERA-40 data, this study contrasts the features of the East Asian summer rainfall frequency during El Niño mature phase between 1958-1977 (pre77) and 1978-2000 (post77). During the El Niño mature phase in June, the Western North Pacific (WNP) subtropical high has enlarged for pre77, compared with the Neutral phase that is not categorized as the El Niño and the La Niño mature phase. The southwesterly wind anomalies associated with the enlargement of the WNP subtropical high cause the positive rainfall frequency anomalies from the western Japan to Taiwan in pre77, compared with the Neutral phase. In post77, the southwesterly winds weakened from the Japan Sea side of Japan to the lower reaches of the Huaihe River associated with the southward displacement of the WNP subtropical high during the El Niño mature phase in June. The weakening of southwesterly winds are responsible for the negative frequency anomalies in this region. As for the El Niño mature phase in July, the WNP subtropical high moves to west in pre77 and expands westward in post77, in comparison with the Neutral phase in pre77 and post77, respectively. During the El Niño mature phase, the southwesterly wind anomalies associated with the westward movement and expansion of the WNP subtropical high cause the positive frequency anomalies from the Yangtze River valley to the western Japan both in pre77 and post77. However the positive anomalies are more obvious in post77. The changes in the WNP subtropical high during the El Niño mature phase is considered to be due to a Rossby wave response to the anomalous cooling over maritime continent. Besides, during the El Niño mature phase in post77, the recent warming of sea surface temperature in the eastern tropical Pacific may cause the westward expansion and southward displacement of the WNP subtropical high.

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