Regional-scale high-latitude extreme geoelectric fields pertaining to geomagnetically induced currents
Regional-scale high-latitude extreme geoelectric fields pertaining to geomagnetically induced currents
复制标题
与地磁感应电流有关的区域尺度高纬度极端地电场
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
C. Ngwira
中科院分区：
文献类型：
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作者：
A. Pulkkinen;E. Bernabeu;Jan F. Eichner;A. Viljanen;C. Ngwira
在高压输电行业需求的推动下，我们利用高纬度图像磁强计阵列的数据来研究区域尺度上的极端地电场特征。我们使用了1993年至2013年的10年S分辨率数据，并使用跨度约500公里的台群上的平均水平地电场幅度来表征这些场。我们发现，与单台站的局域极值有关的地电场结构可能与与区域均匀的地电场有关的结构有很大的不同，后者由单台站的空间平均值很好地表示。视觉外推和空间平均场的严格极值分析表明，100年一遇的极端事件的预期范围分别为3-8V/Km和3.4-7.1V/Km。计算中使用了魁北克参考地面模型。
Motivated by the needs of the high-voltage power transmission industry, we use data from the high-latitude IMAGE magnetometer array to study characteristics of extreme geoelectric fields at regional scales. We use 10-s resolution data for years 1993–2013, and the fields are characterized using average horizontal geoelectric field amplitudes taken over station groups that span about 500-km distance. We show that geoelectric field structures associated with localized extremes at single stations can be greatly different from structures associated with regionally uniform geoelectric fields, which are well represented by spatial averages over single stations. Visual extrapolation and rigorous extreme value analysis of spatially averaged fields indicate that the expected range for 1-in-100-year extreme events are 3–8 V/km and 3.4–7.1 V/km, respectively. The Quebec reference ground model is used in the calculations.