Recent warm winter and decreasing of snow water storage in the snowy cold region and those effect to the basin water balance

近期暖冬和雪寒地区雪水储量减少及其对流域水平衡的影响

基本信息

批准号：
11680522
负责人：
ISHII Yoshiyuki
金额：
$ 2.37万
依托单位：
Hokkaido University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11680522/
关键词：
snowy cold region basin water balance inter-annual variation snow water storage water balance model material cycle 流域水收支水收支モデル

项目摘要

During the past 15 years, hydrological and meteorological observations have been continued in good condition in a snowy mountainous watershed (1.15 km^2) of northern Hokkaido. Annual basin water balance was calculated every water year using these data sets, and inter-annual variations of basin water storage were evaluated. Moreover, a conceptual mathematical model for the basin water balance was proposed. Air temperature was assumed only one variable parameter within the model, and an effect of the changes of snow water storage on the basin water balance due to the winter warming was examined by this model calculation. Recently, it is said that the snowy region in Japan has warm winter and the snowpack amount is decreasing remarkably. We have studied what kinds of influence would be caused by these trends in the basin water balance of the non-anthropogenic watershed. Following results were obtained through our study : 1) the wide range of inter-annual variation in snow water storage depended on not only winter precipitation but also air temperature in the beginning of snow accumulation and ablation periods, 2) snow water storage did not affect so much on the drought flow after the snowmelt season.Water and material budgets were examined at the same watershed during the whole snowmelt season in 1999. Runoff process of the subsurface flow component on the hillslope was analyzed using chemical constituent as a tracer. Stream hydrograph separation by the three components model (snowmelt water, groundwater and those mixed water) showed that groundwater contribution to the stream discharge was almost 40 % of total flow during the whole snowmelt season. This leads to the excessive output of chemical constituent as compared with the total input in the snowpack.

过去15年来，北海道北部雪山流域（1.15km^2）的水文和气象观测一直保持良好状态。利用这些数据集计算每个水年的年度流域水平衡，并评估流域储水量的年际变化。此外，还提出了流域水平衡的概念数学模型。模型中仅假设气温为一个变量参数，并通过该模型计算检验了冬季变暖导致的雪水储量变化对流域水平衡的影响。据了解，近期，日本雪区进入暖冬，积雪量明显减少。我们研究了这些趋势会对非人为流域的流域水平衡产生什么样的影响。通过我们的研究获得以下结果：1）雪水储存量的年际变化范围大，不仅取决于冬季降水，还取决于积雪开始和消融期的气温，2）雪水储存量不影响关于融雪季节后的干旱流量就这么多。1999年整个融雪季节在同一流域进行了水和物质预算检查。使用化学成分分析了山坡上地下流成分的径流过程：追踪器。通过三分量模型（融雪水、地下水和混合水）进行河流水位线分离表明，在整个融雪季节，地下水对河流流量的贡献几乎占总流量的40%。这导致与积雪中的总输入相比，化学成分的输出过多。