Simultaneous scintillometer measurements at multiple wavelengths (pairing visibleudor infrared with millimetre or radio waves) have the potential to provide estimates ofudpath-averaged surface fluxes of sensible and latent heat. Traditionally, the equationsudto deduce fluxes from measurements of the refractive index structure parameter atudthe two wavelengths have been formulated in terms of absolute humidity. Here, it isudshown that formulation in terms of specific humidity has several advantages. Specificudhumidity satisfies the requirement for a conserved variable in similarity theory andudinherently accounts for density effects misapportioned through the use of absoluteudhumidity. The validity and interpretation of both formulations are assessed andudthe analogy with open-path infrared gas analyser density corrections is discussed.udOriginal derivations using absolute humidity to represent the influence of waterudvapour are shown to misrepresent the latent heat flux. The errors in the flux, whichuddepend on the Bowen ratio (larger for drier conditions), may be of the order of 10%.udThe sensible heat flux is shown to remain unchanged. It is also verified that use ofuda single scintillometer at optical wavelengths is essentially unaffected by these newudformulations. Where it may not be possible to reprocess two-wavelength results, auddensity correction to the latent heat flux is proposed for scintillometry, which can beudapplied retrospectively to reduce the error.
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机译：在多个波长上同时进行闪烁仪测量（将可见的或红外与毫米波或无线电波配对）有可能提供对感热和潜热的 udpath平均表面通量的估计。传统上，方程式是根据绝对湿度从公式在两个波长下的折射率结构参数的测量中得出的。在此， u n u003d展示了根据特定湿度进行配方具有多个优点。特定湿度在相似性理论中满足保守变量的要求，并且绝对说明了通过绝对湿度的使用而导致的密度效应分配不均。评估了这两种配方的有效性和解释，并讨论了与开放式红外气体分析仪密度校正的类比。 ud使用绝对湿度代表水/蒸汽影响的原始推导显示出对潜热通量的误解。 udux中的误差取决于鲍文比（在干燥条件下较大），可能约为10％。udud显热通量保持不变。还可以证明，在光学波长上使用单闪烁仪基本上不受这些新的公式影响。如果不可能重新处理两个波长的结果，则建议对潜热通量进行密度校正，以用于闪烁测量，可以追溯应用该校正以减小误差。
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