Second Stage of the Lake Biwa Project

琵琶湖项目的特点是“与空间和航空遥感同步的活动和长期实地观测”、“科学家、工程师和气象学家的合作”和“利用实地观测所吸收的水文气象综合模型了解琵琶湖流域水文循环的目标”。在第二阶段，我们从每年的战役观察转变为在四个代表点进行长期观察。1998年开始在稻田和林区运行永久系统，1999年开始在城区和湖面运行永久系统。根据这一重心向长期观测的转移，我们通过有效利用业务卫星信息，将“季节和逐年变化“和“植被物候”设定为附加目标。当然，为了理解20 km尺度下的尺度效应，模式参数的调整和资料同化是不变的目标，在稻田现场安装了测量或估算辐射收支、热量收支和基于波文比法的水分收支的仪器。光合作用主动辐射计也于今年4月建成。除了用SAT外，林地的测量与水田的测量基本相同。在每个典型日进行了测量叶面积指数和热脉冲速度的活动观察。在湖面和市区站点的测量几乎是相同的，除了基础上设置的整体方法。在办公室使用移动的电话收集这四个研究中心的所有数据。

The Lake Biwa project is featured by "Campaign and Permanent Field Observations Synchronized with Space- and Air-borne Remote Sensing", "Collaboration by Scientists, Engineers and Agriculturists" and "the Goal as Understanding Hydrologic Circulation in the Lake Biwa Basin Using Hydrologic-Meteorological Combined Models Assimilated by the Field Observations". This project has been promoted about 20 groups from around Japan.In the second stage, we shifted weight from every-year campaign observation into permanent observation at four representative points. Operation of the permanent system in paddy field and forested area started in 1998 and in urban area and lake surface in 1999. According to this weight-shift to the permanent observation, we set "seasonal and year-to-year variation " and "vegetation phenology" as additional targets by effectively utilizing operational satellite information. Of course, for understanding the scale effect up to 20 km scale, tuning of model parameters and data assimilation are unchanged targets.At the site of the paddy field instruments for measuring or estimating radiation and heat budget and water budget based on Bowen ratio method were set up. Also photosynthesis active radiometer was set up in this April. Measurement in forested area is almost same as paddy field except for using SAT. Campaign observations for measuring LAI and heat pulse velocity has been carried out on typical days of each. Measurements at lake-surface and urban area sites are almost same except that basis is set on the bulk method. All data from these four sites are collected at office using mobile phone.