Development of the evaluation technique on diffusion coefficient of snowpack for carbon dioxide using acoustical property

利用声学特性评价积雪二氧化碳扩散系数技术的开发

• 批准号: 17540421
• 负责人: KOMINAMI Yasuhiro
• 金额: $ 2.02万
• 依托单位: National Agricultural Research Organization
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17540421/
• 关键词: carbon dioxide; snowpack; sound velocity; acoustic attenuation coefficient; gas diffusivity; CO2; フラックス; 音響; 透過係数; 減衰係数; CO_2; 溶存二酸化炭素; PCO_2

1. Sound velocity and the acoustic attenuation coefficient of the snowpack of various snow conditions were measured, and relation between physical properties of snow and acoustical property were examined. The sound source used are sine wave from 200Hz to 8000Hz every 1/3 octaves.(1) The sound velocity of the air of the snowpack depends on the winding level of the diffusion mute just like the gas diffusion coefficient. However it has been understood that the sound passes the beeline in the winding space while the gas diffusion coefficient depends on the mean distance of the winding space.(2) The acoustic attenuation coefficient that spread in the space air was in inverse proportion to the square of the space sire, and it was confirmed that it was a phenomenon similar to the attenuation of the mass flow in the space caused by the pressure fluctuation. And the acoustic attenuation coefficient of the uniting snow particles is in inverse proportion to the snow density, and guessed to be the one by the mechanism of the interception by the effect of mass to the damping coefficient of the spreading sound.2. The carbon dioxide concentration was continuously measured in three depth of the natural snowfall, and the phenomenon of the gas diffusivity of the appearance of the snow in the vicinity of the surface increasing by the wind was confirmed. From the above result, the sound velocity and the acoustic attenuation coefficient of the snowpack are related to the character to decide the gaseous environment of the snowpack..

1。测量了各种雪条件下的积雪的声速和声学衰减系数，并检查了雪的物理特性与声学特性之间的关系。所使用的声源是每1/3八度的正弦波从200Hz到8000Hz。（1）Snekpack空气的声速取决于扩散静音的绕组水平，就像气体扩散系数一样。然而，人们已经理解，声音在绕组空间中传递了键线，而气体扩散系数取决于绕组空间的平均距离。（2）（2）在空气中传播的声学衰减系数与空间正方形的正方形相反，并且证实这是通过质量流动的现象相似的现象。统一雪颗粒的声学衰减系数与雪密度相反，并通过质量对散布声音的阻尼系数的效果造成拦截机理猜测是一种。在自然降雪的三个深度中连续测量二氧化碳浓度，并确认了降雪的气体外观的现象在表面附近通过风增加。从上面的结果来看，积雪的声速和声学衰减系数与角色有关，以确定积雪的气态环境。

项目成果

Measurement of Dissolved Carbon dioxide in Runoff of Snow Melt Water(2).

雪融水径流中溶解二氧化碳的测量(2)。

• 发表时间: 2006
• 作者: KOMINAMI;Y.;YOKOYAMA;K.
• 通讯作者: K.

The role of seasonal snow cover on carbon dioxide cycle.

季节性积雪对二氧化碳循环的作用。

• 发表时间: 2006
• 期刊: Applied Meteorology and Climate Resources 19
• 作者: KOMINAMI;Y.
• 通讯作者: Y.

Relation between acoustic attenuation coefficient and characteristic of snow.

声衰减系数与雪特性的关系。

• 发表时间: 2008
• 作者: KOMINAMI;Y.;YOKOYAMA;Y.
• 通讯作者: Y.

Measurement of Sound Velocity in Deposited Snow.

沉积雪中声速的测量。

• 发表时间: 2008
• 作者: KOMINAMI;Y.;YOKOYAMA;Y.
• 通讯作者: Y.

安価なCO2センサーを大気中のフラックス測定に使ってみた

我尝试使用廉价的二氧化碳传感器来测量大气通量。

• 发表时间: 2007
• 作者: KOMINAMI;Y.;YOKOYAMA;Y.;小南靖弘
• 通讯作者: 小南靖弘