1. <sub id="zy88n"></sub>
        1. <blockquote id="zy88n"></blockquote>
          欧美黑人又大又粗xxxxx,人人爽久久久噜人人看,扒开双腿吃奶呻吟做受视频,中国少妇人妻xxxxx,2021国产在线视频,日韩福利片午夜免费观着,特黄aaaaaaa片免费视频,亚洲综合日韩av在线

          Scientists caught flatfooted by an increasingly "capricious" Magnetic North

          Source: Xinhua| 2019-01-13 14:24:01|Editor: xuxin
          Video PlayerClose

          WASHINGTON, Jan. 13 (Xinhua) -- The geomagnetic field makes lives possible by deflecting harmful radiation and keeping water and atmosphere in place. But now it's acting up, with increasingly unpredictable bipolar course change which renders compasses redundant.

          Unlike previous anomalies recorded at intervals averaging several hundred thousand years, recent movements of the magnetic poles have been alarmingly "erratic" -- frequent and faster -- from around 15 km per year before the mid-1990s to around 55 km right now, skittering away from Canada and towards Siberia, according to science journal Nature.

          The Earth's magnetic field is generated in the fluid outer core of sloshing molten iron by a self-exciting dynamo process. However, abrupt and irregular changes within the core has prompted scientists to update the World Magnetic Model, which describes the the planet's magnetic field and underlies all modern navigation, from the systems steering ships at sea to Google Maps on smartphones.

          The Clock is ticking right now for geomagnetists to release the updated model by the Jan. 15 deadline, the most recent of which issued in 2015 and supposed to last until 2020, according to Nature.

          Researchers from the U.S.-based National Oceanic and Atmospheric Administration and the British Geological Survey in Edinburgh has been checking annually to see if the model is able to capture all the variations in Earth's magnetic field.

          Starting 2018, the World Magnetic Model was not functioning well, its precision close to exceeding "the acceptable (safe) limit for navigational errors," Nature reported.

          Besides such errors, a disrupted geomagnetic field may also leave living beings on the planet vulnerable to an increased dosage of solar radiation.

          TOP STORIES
          EDITOR’S CHOICE
          MOST VIEWED
          EXPLORE XINHUANET
          010020070750000000000000011100001377403181
          主站蜘蛛池模板: 久久国产毛片| 狠狠色丁香久久综合频道日韩| 日韩蜜桃AV无码中文字幕不卡高清一区二区 | 精品国产综合成人亚洲区| 一区二区三区福利在线视频| 国产成人综合亚洲AV第一页| 精品久久久无码人妻字幂| 人人妻人人澡人人爽不卡视频 | 97人人模人人爽人人| 最新系列国产专区|亚洲国产| 久久无码免费的a毛片大全| 国产视频一区二区三区四区视频 | 男女啪啪激烈无遮挡动态图| 日韩av在线不卡免费| 国产激情艳情在线看视频| 日日撸 夜夜撸| 亚洲午夜成人精品电影在线观看| 精品国产高清自在线一区二区| 亚洲综合国产一区| 夜先锋av资源网站| 久久久久无码精品国产app| 91无码人妻精品一区二区蜜桃| 91福利精品老师国产自产在线| 日本免费有码中文字幕| 91热视频在线观看| 国产午夜福利在线观看播放| 国产精品成人精品久久久| 亚洲中文字幕av一区| 中文字幕无码免费久久9一区9 | 精品国产一区二区三区AV性色| 大胸美女吃奶爽死视频| 国产最新av在线播放不卡| 97精品依人久久久大香线蕉97| 国产欧美日韩中文字幕| 亚洲第一黄色网址| 鲁丝片一区二区三区免费| 性欧美大战久久久久久久| 中文字幕久久久久人妻中出| 台湾佬自拍偷区亚洲综合| 国产精品无码专区第一页| 亚洲人成电影网站 久久影视|