Quantifying the Effect of Irrigation on Nonlocal Aspects of the Atmosphere
Quantifying the Effect of Irrigation on Nonlocal Aspects of the Atmosphere
复制标题
量化灌溉对大气非局部方面的影响
DOI：
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
B. Ancell
中科院分区：
文献类型：
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作者：
C. J. Nauert;B. Ancell
几十年来，人们一直在使用观测和数值天气预报模型研究灌溉对天气的影响。然而，很少有人冒险研究强强迫天气系统通过期间产生的对流天气的非局地下游影响，或者我们称之为高影响天气。这种差异的一个原因是混沌播种的影响（Ancell等人，2018年，https：//doi.org/10.1175/BAMS ‐D <$17 <$0129.1）在降水或对流发生的地区，从模型物理学中，在几个小时内造成下游降水量的不切实际的变化。混沌播种的影响使得很难区分哪些下游天气变化是灌溉引起的反馈，哪些是混沌播种本身的产物-这是这项工作的中心区别。作者调查了德克萨斯州狭长地带当地灌溉的地表反馈产生的大气扰动是否可以使用高级研究天气研究和预测模型3.5.1版在几天和数千公里的时间和空间尺度上显着改变下游大气结构。灌溉是通过扰动土壤水分的网格点变量来表示的，96小时模拟的每9个案例研究中有75个成员，其中25个成员代表在纽约应用的不切实际的扰动，用于解释混沌播种。作者发现灌溉影响下游和非本地其他地方超越混沌播种的修改，在三个9例中的降水变化发生在气旋，干线，冷锋轨道的变化为50毫米或更多。
Irrigation‐induced effects on weather have been studied for several decades using observations and numerical weather prediction models. However, few have ventured to investigate nonlocal, downstream effects on convective weather produced during the passage of strongly forced synoptic systems, or as we refer to as high‐impact weather. One reason for this discrepancy is the influence of chaos seeding (Ancell et al., 2018, https://doi.org/10.1175/BAMS‐D‐17‐0129.1) from the model physics in areas where precipitation or convection are occurring, causing unrealistic changes in precipitation far downstream in a matter of hours. The effects of chaos seeding have made it difficult to distinguish what downstream weather modifications are irrigation‐induced feedbacks and what are products of chaos seeding itself—a distinction at the center of this work. The authors investigate whether atmospheric perturbations produced by land‐surface feedbacks from local irrigation in the Texas Panhandle can significantly modify downstream atmospheric structure on time and space scales across days and thousands of kilometers using the Advanced Research Weather Research and Forecasting Model Version 3.5.1. Irrigation is represented by perturbing the grid point variable of soil moisture with an ensemble of 75 members per 9 case studies for 96‐hr simulations, with 25 members representing unrealistic perturbations applied in New York accounting for chaos seeding. The authors find irrigation influences downstream and nonlocally elsewhere beyond the modification of chaos seeding, with effects shown in three of nine cases amid precipitation shifts occurring around cyclone, dryline, and cold front tracks with changes of 50 mm or more.