Challenges and Capabilities in Estimating Snow Mass Intercepted in Conifer Canopies With Tree Sway Monitoring
Challenges and Capabilities in Estimating Snow Mass Intercepted in Conifer Canopies With Tree Sway Monitoring
复制标题
通过树木摇摆监测估算针叶树冠层截获的雪量的挑战和能力
DOI：
10.1029/2021wr030972
复制
发表时间：
2022
影响因子：
5.4
通讯作者：
Small, Eric E.
中科院分区：
文献类型：
--
作者：
Raleigh, Mark S.;Gutmann, Ethan D.;Van Stan, II, John T.;Burns, Sean P.;Blanken, Peter D.;Small, Eric E.
森林流域的积雪积累取决于冠层拦截的雪量及其升华、卸载和融化的划分。冠层积雪测量的缺乏限制了我们评估模拟冠层过程和预测积雪的模型的能力。我们测试了监测风引起的树木摇摆变化是否是一种检测雪拦截和量化冠层雪水当量（SWE）的可行技术。在科罗拉多州的6年时间里，我们监测了两种针叶树每小时的摆动，每棵针叶树都用加速度计采样，频率为12赫兹。我们开发了一种方法来区分由于树木刚度的热效应与拦截雪团造成的摇摆频率变化。超过60%有冠层积雪的日子有不能与热效应区分的摇摆信号。然而，树木摆动的较大变化通常不能归因于热效应，并且根据分类的PhenoCam图像证实，树冠积雪存在93%-95%的时间。通过摇摆试验，我们将摇摆变化转换为冠层SWE，这与附近SNOTEL站点的总暴风雪量相关（Spearmanr= 0.72至0.80,p< 0.001）。冠层SWE越大，风暴温度在- 7°C和0°C之间，风速小于4 m s - 1。低冠层SWE在温度较低、风速较高的风暴中占优势。监测树木的摇摆是量化林冠SWE的可行方法，但在将摇摆变化转化为质量以及区分热质量和雪质量对树木摇摆的影响方面仍然存在挑战。
Snowpack accumulation in forested watersheds depends on the amount of snow intercepted in the canopy and its partitioning into sublimation, unloading, and melt. A lack of canopy snow measurements limits our ability to evaluate models that simulate canopy processes and predict snowpack. We tested whether monitoring changes in wind‐induced tree sway is a viable technique for detecting snow interception and quantifying canopy snow water equivalent (SWE). Over a 6 year period in Colorado, we monitored hourly sway of two conifers, each instrumented with an accelerometer sampling at 12 Hz. We developed an approach to distinguish changes in sway frequency due to thermal effects on tree rigidity versus intercepted snow mass. Over 60% of days with canopy snow had a sway signal that could not be distinguished from thermal effects. However, larger changes in tree sway could not generally be attributed to thermal effects, and canopy snow was present 93%–95% of the time, as confirmed with classified PhenoCam imagery. Using sway tests, we converted changes in sway to canopy SWE, which were correlated with total snowstorm amounts from a nearby SNOTEL site (Spearmanr= 0.72 to 0.80,p< 0.001). Greater canopy SWE was associated with storm temperatures between −7°C and 0°C and wind speeds less than 4 m s−1. Lower canopy SWE prevailed in storms with lower temperatures and higher wind speeds. Monitoring tree sway is a viable approach for quantifying canopy SWE, but challenges remain in converting changes in sway to mass and distinguishing thermal and snow mass effects on tree sway.
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影响因子：
6.2
作者：
E. Gutmann;J. Stan;J. Friesen;D. Aubrey;J. Lundquist
通讯作者：
E. Gutmann;J. Stan;J. Friesen;D. Aubrey;J. Lundquist
树木摇摆周期——树冠分类和林分竞争的一个可能的新参数
DOI：
--
发表时间：
1962
期刊：
影响因子：
--
作者：
M. Sugden
通讯作者：
M. Sugden
DOI：
--
发表时间：
1999
期刊：
影响因子：
--
作者：
D. Green;J. Evans;J. Logan;W. Nelson
通讯作者：
W. Nelson
影响因子：
6.8
作者：
Burns, Sean P.;Swenson, Sean C.;Blanken, Peter D.
通讯作者：
Blanken, Peter D.
影响因子：
5.2
作者：
Ciruzzi, Dominick M.;Loheide, Steven P.
通讯作者：
Loheide, Steven P.