Study on development of method for monitoring of environment relating snow area variations in a wide area of the Yamagata Prefecture using satellite observations

1)与山形县的研究人员一起组成了一个研究小组，并定期举行一系列小组会议。2）通过与山形县立卫生研究所的合作研究，明确了花粉扩散阶段与积雪分布的关系，从而能够预测花粉扩散阶段。3）利用NOAA卫星搭载的AVHRR探测积雪面积的方法是先进的，可以定期制作积雪面积的质量控制结果。4）采用先进的积雪检测方法，获得了1989-1998年1 km空间分辨率的积雪信息，并将其存入数据库。该数据库已在与山形县的合作研究中使用，并将用于各种类型的研究。5）2001年3 ~ 6月，将所探测到的积雪面积真实的分发给山形县和其他研究人员，表明本研究成果可用于业务应用。

1) A research group was formed together with the researchers belonging to the Yamagata Prefecture, and a series of group meeting was held regularly. Through the meetings, usage of the snow area information for the wide Tohoku region has been discussed in the areas of pollen dispersion, forest control and agriculture.2) Through the cooperative research with the Yamagata Prefectural Institute of Public Health, a relationship between the stage of pollen dispersion and the snow distribution become clear, which enable us to forecast the stage of dispersion. This result has been published in the Japanese J. of Palynol.3) The method of snow-area detection using AVHRR on board NOAA satellites is advanced, and it become possible to produce quality-controlled results of the snow area regularly. Thtrough this procedure, anybody, even a beginner can generate the snow-area map using the satellite images.4) Using tne advanced snow-area detection method, information of the snow area with 1km spatial resolution is obtained for 1989-1998, and stored in a database. The database is used in the present cooperative study with the Yamagata Prefecture, and will be used for various type of researches.5)The detected snow area was distributed in real time to the Yamagata prefecture and the other researchers for March to June in 2001, which demonststrated that the present research result can be uaed for operational application.