Green spaces in urban areas as well as water surfaces have been expected to mitigate the urban heat island effect. In the hot and humid summers in Japan, their cooling effect is especially valuable as a natural resource for city planning. In this paper, we show the results of micro-climatologic observations performed in and around the large park Shinjuku Gyoen during summer. The park is 58.3ha, and located in one of the main business districts of Tokyo. It consists of a dense forest area, lawn area, and ponds. The topography in the park is almost completely flat but is a few meters lower around the ponds than their surroundings.
We observed the air temperature distribution in and around the park at 1-min intervals. We placed a total of 88 automatic temperature recorders along three measuring lines which crossed through the park. To record the cold air-seep phenomenon during calm conditions, we placed four three-dimensional ultrasonic anemometer-thermometers along the park boundary and at the center of the park. Their measuring height was about 1.5 m above ground, and sampling frequency was 10Hz.
The park was always cooler than the surrounding built-up area. On the other hand, there was a temperature difference within the park, i.e., the cool-island intensity was larger for the park forest during the daytime, but larger for the park lawn surface during the nighttime. In daytime windy conditions, a cold air mass from the green space chilled the leeward built-up area to about 250 m from the park boundary.
In clear calm midnight conditions, wind flowed out from the park to the surrounding area at all measuring points on the boundary. The wind direction changed and began to flow out obviously at about 22:00 LST and air temperature on the park boundary fell 1°C at the same time. After that, the decline in air temperature was not constant, and periodic oscillation was seen at some points. These results imply the accumulation of a cold air mass in the park and its gravitational outflow into the surrounding area. A significant air temperature drop in the adjacent built-up area was observed within the range of 80-90 m from the park boundary. This cold air seep is limited within a certain range through the night regardless of cool-island intensity.
Air temperature above the lawn surface was lower than that under tree crowns during the night. This temperature difference was diminished by intermittent cloud cover. Thus the radiative cooling on the lawn surface should be the source of cold air seeping out at the park boundary.
During the seeping out of cold air, the cool-island intensity increases, but sensible heat flux (at the park lawn surface) was almost zero. The cooling ability of parks is not directly related to cool-island intensity.

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Since the City Planning Act in 1968, residential land use has been one of the most important policy issues in many city governments. Under these circumstances, especially in local cities, agricultural cooperatives have been expected to play a role in orderly land use. This paper aims to clarify the roles of the agricultural cooperative in the development policy of a local city by analyzing the policy process that occurred during residential development in Matsumoto City, Nagano Prefecture. The policy process is outlined as follows.
1) Agenda setting
In the early 1980s, the administration of the city was under fiscal restraints because of public investments, with disorderly developments in urbanization control areas. On the other hand, the administration was concerned about the population drain to nearby cities owing to the controlled development. As a result, the administration decided to expand urbanization promotion areas and to fix the residential population there.
2) Policy decision
A consensus among the farmers of the affected vicinities had to be established before expanding urbanization promotion areas. As a policy response for this agenda, in 1984 the administration established the Workshop of Regional Development to collaborate with the agricultural cooperative (JA Matsumoto Highland and JA Matsumoto City) as a farmers' interest group. The Regional Development Workshop promoted land readjustment projects in new urbanization promotion areas.
3) Policy implementation
In land readjustment projects, the agricultural cooperative was proactive in playing the role of coordinator between farmers and the administration and was successful in establishing a consensus among farmers. Consequently, the roles of the agricultural cooperative were indispensable for the administration to carry out its policy. Meanwhile, the agricultural cooperative was not only the coordinator but also an actor in the private sector which pursued development benefits from real estate deals and fund operations. These land readjustment projects were agreed upon between the administration and the agricultural cooperative.
As a result of the policy process, residential development in Matsumoto City advanced steadily after the mid-1980s. The Workshop of Regional Development institutionally maintained the roles of the agricultural cooperative and worked to achieve this growth.

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A local strong south-southwesterly wind called Suttsu-dashi often prevails from May to July around the Suttsu region in the western part of Hokkaido, Japan. To elucidate the characteristics of this local wind, field observation was carried out in the region from Kuromatsunai to Suttsu Bay during May 9 to September 22, 1998. The observed data were analyzed together with other meteorologic data from synoptic weather maps, AMeDAS data, and aerological data from Sapporo Observatory. In addition, synoptic climatologic aspects of the Suttsu-dashi were statistically analyzed for past decadal years based on meteorologic data from the Suttsu Observatory and synoptic weather maps. Synoptic weather maps were classified into three types and the relationship between the Suttsu-dashi and synoptic pressure patterns was also investigated.
The main results and discussion can be summarized as follows:
1) In many cases off the Suttsu-dashi, the surface weather map is characterized by a pressure pattern with an anticyclone over the Sea of Okhotsk (Okhotsk high type), and the southerly-to-southwesterly strong wind lasts relatively longer compared with the case of other pressure pattern types. However, no obvious relationship can be seen between the duration and the wind speed of the Suttsu-dashi.
2) The results of the field observation demonstrate that the strong wind mainly prevails over the region to the north of Minamisakkai and forms a discontinuity line of wind speed between Shirozumi and Minamisakkai. The position of this discontinuity line corresponds to the valley from Kuromatsunai to Suttsu Bay.
3) The wind speed difference between the Suttsu side and Utasutsu side of Suttsu Bay is not obvious. However, a difference in wind direction between the two sides is found, that is, it is south-southwesterly on the Utasutsu side and south-southeasterly on the Suttsu side. This suggests that one of the causes of the Suttsu-dashi can be attributed to horizontal wind divergence.
4) A proportionality relation is found between the wind speeds at Kitasakkai and Tarukishi in many cases. However, this relation changes if the wind speed at Kitasakkai exceeds the critical wind speed of about 7 ms^-1. When the wind speed at Kitasakkai is greater than the critical wind speed, the rate of increase in the wind speed at Tarukishi sometimes becomes higher than in cases with the wind speed less than critical. Surface weather maps in this case are categorized into the Okhotsk high-type only. In contrast, such features of wind speed cannot be found at Utasutsu.

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