亚洲аv天堂无码,久久aⅴ无码一区二区三区,96免费精品视频在线观看,国产2021精品视频免费播放,国产喷水在线观看,奇米影视久久777中文字幕 ,日韩在线免费,91spa国产无码

      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: 久久五十路丰满熟女中出| 石台县| av片在线观看永久免费| 真实播放国产乱子伦视频| 亚无码乱人伦一区二区| 久久久一本精品99久久| 精品熟妇av一区二区三区四区| 国产精品白浆在线观看| 成人白浆一区二区三区在线观看| av天堂吧手机版在线观看| 人妻无码在线免费| 日本xxxx色视频在线观看| 亚洲美女一区二区三区| 一区二区三区久久含羞草| 2021国产精品久久| 亚洲av色香蕉一二三区| 日产精品一区二区免费| 亚洲成AV人片无码不卡| 在线视频青青草猎艳自拍69| 久久亚洲AV成人一二三区| japanese精品少妇| 国产美女久久精品香蕉69| 国产精品美女久久久久av爽李琼| chinese中国人妻video| 国产精品推荐天天看天天爽| 国产一区二区三区白浆在线观看| 彝良县| 亚洲中文字幕永久网站| 亚洲精品乱码久久久久久按摩高清| 女子初尝黑人巨嗷嗷叫| 国产av普通话对白国语| 91久久国产福利自产拍| 国产美女久久久亚洲综合| 国产成人一区二区三区影院免费| 国产精品不卡无码AV在线播放| 岳阳县| 国产成人一区二区三区高清| 激情人妻福利资源在线| 一区二区韩国福利网站 | 久久免费精品视频老逼| 一本一本久久a久久精品综|