The theory—advanced by Rutgers professor Jennifer Francis and other scientists—is that the rapidly warming Arctic is affecting the jet stream in ways that can contribute to bone-chilling weather in other parts of the Northern Hemisphere: To understand how it works, it first helps to think of the jet stream as a river of air that flows from west to east in the Northern Hemisphere, bringing with it much of our weather. Its motion—sometimes in a relatively straight path, sometimes in a more loopy one—is driven by a difference in temperatures between the equator and the North Pole. Southern temperatures are of course warmer, and because warm air takes up more space than cold air, this leads to taller columns of air in the atmosphere. “If you were sitting on top of a layer of atmosphere and you were in DC, looking northward, it would be like looking down a hill, because it’s warmer where you are,” explains Francis. The jet stream then flows “downhill,” so to speak, in a northward direction. But it’s also bent by the rotation of the Earth, leading to its continual wavy, eastward motion. As the Arctic rapidly heats up, however, there’s less of a temperature difference between the equator and the poles, and the downhill slope in the atmosphere is accordingly less steep. That shrinking temperature difference is what wreaks havoc on the jet stream. “When the jet stream gets weaker, it meanders more,” explained Francis in an interview this week. “It wanders north and south and when it gets into one of these wandering and wavy patterns, that’s when we see these pools of cold air pulled southward.” Those pools of cold air are what vast parts of the country are experiencing right now.
Breaking News: "I too have a Nuclear Button, but it is a much bigger & more powerful one": President Trump taunted Kim Jong-un over North Korea's arsenal.
The greatest & most pressing challenge & risk is that the post War World II Global Economic and Political Order is inevitably losing its competences of leading & bonding, as well as its legitimacy. The old order established in old era can neither be saved nor made great again. The old era is gone and the old order is game over. It has to be replaced.
Democrats on the House Intelligence Committee are threatening to publish a “minority report” detailing all the ways in which Republicans attempted to block or harm the investigation into Trump campaign collusion with Russia.
何尔（F.W.Hall）在Oxford,Clarenden Press,1913年古典文学之良友丛书（Companion to Classical Text）中著有“古典文学作者与其作品之手抄本的权威性”（MS Authorities for the Text of the Chief Classical Writers），其中资料抄录如下： http://cclw.net/gospel/new/tzdp/htm/04.htm
森德斯（C.Sanders）在《英国文学史研究简介》(Introduction to Research in English Literary History)一书中曾列举三种基本考验及编纂史料的原则：参考文献的测验（Bibliographical Test）、文内证据的测验（Internal Evidence Test）、及文外证据的测验（External Evidence Test）。 所谓参考文献的测验乃是检察所留传下来的文件，看其中章节及文字的真伪。换句话说，在缺乏原本的情况下，抄本的可靠性如何？抄本的数目共有多少？又抄本与原本之间共相隔多少时间？
