The cloud distribution around the Northeast Japan under the winter monsoon situation has been already known roughly as shown in Fig. 1. The relation between the cloud dis-tribution and local anticyclones and cyclones is, however, not mentioned around the North-east Japan as was done by the author around the Central Japan and the Southwest Japan (Nishina, 1984a, b). The, purpose of this study is to discuss this relation, including the re-lation between the “Ishikari Front” and the cloud distribution.
In this study, GMS (Geostationary Meteorological Satellite) sector visible pictures at 09 JST in four winters (December, January and February) from December of 1979 to Febru-ary of 1983 were analyzed on the 51 days when at least one of the convective band clouds from the Mamiya Straits or from Primorskij appeared and another band cloud except two band clouds from the Funka Bay or from the Tsugaru Straits appeared. These 51 days were classified into four groups, as shown in Table 1, according to the coast line on the Japan Sea side of Hokkaido where the convective band clouds were located. A few typical days of each group were selected for analysis. Upper and surface meteorological elements and weather maps were analyzed on the most typical day in each group.
From 850 mb weather map, there exists commonly cold air advection over the North-east Japan among the four groups. But upper wind direction near 850 mb and the character-istics of local surface weather maps are different among them.
These analyses are summarized as follows (1) The location of the convective band clouds on the Japan Sea side of Hokkaido cor-responds to the location of local cyclones. Without convective band cloud, these local cyclones are generated.
(2) The generation of local anticyclones in Hokkaido and the location of local cyclones on the Japan Sea side of Hokkaido are different among upper wind direction near 850 mb over the Northeast Japan. Under west-northwesterly upper wind, local cyclones are gener-ated around Rumoi and the Ishikari Bay. In this case, no anticyclone analyzed with closed isobars is generated in the inland of Hokkaido. Under northwesterly or north-northwesterly upper wind, local cyclones are generated around the Ishikari Bay and Suttsu. Local anti-cyclones analyzed with closed isobars are generated clearly in the inland of Hokkaido and in Kucchan.
(3) The “Ishikari Front”, which was mentioned by Kawamura (1961), is formed by the convergence of the surface wind blowing toward the local cyclone in the Ishikari Plain or around Rumoi under west=northwesterly upper wind. It often overlaps with the convective band cloud from Primorskij. It differs essentially from the “Ishikari Front” mentioned by Okabayashi (1969b), which is formed by the convergence between the surface wind from the inland of Hokkaido and winter monsoon under northwesterly upper wind and cor-responds to the end of the connective band cloud from the Mamiya Straits.
(4) The band cloud from the Tsugaru Straits corresponds to the location of cold air outburst. The band cloud from the Funka Bay also corresponds to it, but when a local anticyclone in Kucchan is clearly generated under north-northwesterly upper wind, cold air current from this local anticyclone is brought to the location of cold air outburst. The band cloud appears from this location. Other band clouds on the Pacific Ocean side of the Northeast Japan appear from the local cyclones in the leeward of the Hidaka Mountains, the Kitakami Mountains, or the Oou Mountains. The locations of these local cyclones are different among upper wind direction near 850 mb. But under the generation of these local cyclones, there sometimes appears a cloud streak with short CFP (cloud free path) or a group of cloud showing the existence of mountain wave instead of band cloud.

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The purpose of this study is to make clear the conditions of greenery conservation pro-jects by the municipal governments and to examine the new trends towards the positive conservation policy adopted in Ichikawa and Abiko cities, Chiba Prefecture. In this paper, the greenery means woodlands, one of the most important amenity resources in urban environment. The general findings are summarized as follows.
After 1968, a great deal of private woodlands have been converted to urban land use mainly because of the development of residential districts in the Urbanization Promotion Area of the City Planning District. Under the existing circumstances, municipal govern-; menns which are putting emphasis on the conservation of woodlands in urbanized areas issued municipal ordinances regarding greenery conservation and civil forests as recreation space after about 1971. Fifteen cities in the urbanized region in Chiba Prefecture now put these municipal ordinances into operation. There is a positive correlation between the area of preserved woodlands and the population size of fifteen cities studied.
However, these municipal ordinances do not have a positive conservation effect, because woodlands are still being encroached by urban land use. It is necessary to impose legal control in order to preserve surely the remaining woodlands in the Urbanization Promotion Area. In this sense, the enforcement of the positive greenery conservation by the Ichikawa and Abiko municipal governments under the provision of “The Law for the Conservation of Urban Green Space” needs to be highly evaluated as a new trend in the protection of environmcnt

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