During the winter of 2015–2016, an extraordinary warming event occurred in the troposphere in the Arctic region. The above-normal temperatures extended from the surface to 300 hPa in the Arctic. The number of extremely warm days derived from the surface air temperature revealed that this event was the most significant warming event since 1980. It was found that the tropospheric warming anomaly was not fully dependent on the warming anomalies at lower levels, and it formed earlier than the lower anomalies. In December 2015, there were three obvious warm centers in the troposphere in the mid-high latitude regions in eastern North America, northern Europe, and western Asia. Albeit the strongest warming anomaly occurred in North America, the prominent warm advection to the Arctic region was transported from northern Europe during the initial stage of the Arctic mid-upper tropospheric warming. Further investigation revealed that the teleconnection wave train stretching across North America to the North Atlantic and northern Europe contributed significantly to the existence of a poleward transport channel from northern Europe to the Arctic. The wave train spread from west to east and produced a strong southerly wind disturbance over the warm region in northern Europe. As a result, extraordinary poleward heat and water vapour transport occurred across the polar boundary causing substantial warming in the Arctic mid-upper troposphere. During the extreme Arctic tropospheric warming event, the dynamic processes related to the heat transport over northern Europe directly contributed to the advanced rapid warming in the Arctic mid-upper troposphere; whereas, the dynamic and thermal processes associated with the transport across the Arctic boundary jointly maintained the late stage of Arctic warming.

中文翻译：

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2015—2016年冬季北极对流层快速增温及其与中高纬遥相关波列的关系

2015-2016年冬季，北极地区对流层发生异常变暖事件。北极高于正常的温度从地表延伸到 300 hPa。从地表气温推导出的极暖日数显示，此次事件是1980年以来最显着的增暖事件。发现对流层增暖异常并不完全依赖于低层增暖异常，其形成时间早于较低的异常。2015年12月，北美东部、欧洲北部和亚洲西部的中高纬度地区对流层出现三个明显暖心。尽管最强的变暖异常发生在北美，在北极中上层对流层变暖的初始阶段，从北欧输送到北极地区的主要暖平流。进一步的调查显示，跨越北美到北大西洋和北欧的遥相关波列对从北欧到北极的极向传输通道的存在做出了重大贡献。波列自西向东传播，在北欧温暖地区上空产生强烈的南风扰动。结果，异常的热量和水汽传输发生在极地边界，导致北极中上层对流层显着变暖。在极端的北极对流层变暖事件期间，与北欧热传输相关的动力过程直接导致了北极中上层对流层的快速变暖；而与穿越北极边界的运输相关的动力和热力过程共同维持了北极变暖的晚期阶段。