Accurate dust-source characterizations are critical for effectively modeling dust storms. A previous study developed an approach to manually map dust plume-head point sources in a geographic information system (GIS) framework using Moderate Resolution Imaging Spectroradiometer (MODIS) imagery processed through dust-enhancement algorithms. With this technique, the location of a dust source is digitized and recorded if an analyst observes an unobscured plume head in the imagery. Because airborne dust must be sufficiently elevated for overland dust-enhancement algorithms to work, this technique may include up to 10 km in digitized dust-source location error due to downwind advection. However, the potential for error in this method due to analyst subjectivity has never been formally quantified. In this study, we evaluate a version of the methodology adapted to better enable reproducibility assessments amongst multiple analysts to determine the role of analyst subjectivity on recorded dust source location error. Four analysts individually mapped dust plumes in Southwest Asia and Northwest Africa using five years of MODIS imagery collected from 15 May to 31 August. A plume-source location is considered reproducible if the maximum distance between the analyst point-source markers for a single plume is ≤10 km. Results suggest analyst marker placement is reproducible; however, additional analyst subjectivity-induced error (7 km determined in this study) should be considered to fully characterize locational uncertainty. Additionally, most of the identified plume heads (>90%) were not marked by all participating analysts, which indicates dust source maps generated using this technique may differ substantially between users.

准确的粉尘源表征对于有效地模拟沙尘暴至关重要。先前的研究开发了一种方法，该方法使用通过除尘算法处理的中分辨率成像分光辐射计（MODIS）图像在地理信息系统（GIS）框架中手动绘制除尘羽头点源。使用这种技术，如果分析人员观察到图像中的烟羽头未遮挡，则灰尘源的位置将被数字化并记录下来。由于必须充分提高空中尘埃才能使陆上尘埃增强算法起作用，因此该技术可能包括由于顺风平流而导致的数字化尘埃源位置误差长达10 km。但是，由于分析师的主观性，这种方法潜在的错误尚未得到正式量化。在这个研究中，我们评估了该方法的一种版本，该方法适用于更好地在多个分析人员之间进行可重复性评估，以确定分析人员主观性对记录的粉尘源位置误差的作用。四名分析人员使用从5月15日到8月31日收集的五年MODIS影像，分别绘制了西南亚和西北非的尘埃羽图。如果单个羽流的分析器点源标记之间的最大距离≤10 km，则认为羽流源位置可重现。结果表明，分析标记的放置是可重复的。但是，应考虑额外的分析者主观性引起的误差（在本研究中确定为7 km），以充分表征位置不确定性。此外，大多数识别出的羽头（> 90％）并未被所有参与分析的人标记，