<blockquote id="pl83f"><p id="pl83f"></p></blockquote>
<s id="pl83f"><li id="pl83f"></li></s>

      
      
      <sub id="pl83f"><rt id="pl83f"></rt></sub>

        <blockquote id="pl83f"><p id="pl83f"></p></blockquote>
        <sub id="pl83f"><rt id="pl83f"></rt></sub>
        女人的天堂av在线播放,3d动漫精品一区二区三区,伦精品一区二区三区视频,国产成人av在线影院无毒,亚洲成av人片天堂网老年人,最新国产精品剧情在线ss,视频一区无码中出在线,无码国产精品久久一区免费

        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: 公与淑婷厨房猛烈进出视频免费| 亚洲色偷偷色噜噜狠狠99 | 夜夜嗨av一区二区三区| 国产精品国产三级国产专i| 婷婷开心深爱五月天播播| 极品美女高潮呻吟国产剧情| 伊人激情一区二区三区av| 色噜噜狠狠成人综合| 国产乱码精品一区二三区| 一本精品中文字幕在线| 年轻女教师hd中字| 成人亚洲av免费在线| 国产精品一区二区三区精品| 久久96热人妻偷产精品| 精品无码国产日韩制服丝袜| 成人免费AV一区二区三区| 精品亚洲精品日韩精品| 一级欧美牲交大片免费观看| 久久亚洲av成人一二三区| 亚洲aⅴ男人的天堂在线观看 | 四虎影视国产精品永久在线| 色综合中文| 91中文字幕在线一区| 免费看无码自慰一区二区| 61精品人妻一区二区三区| 国产日产免费高清欧美一区| 美女内射福利大全在线看| 国产福利姬喷水福利在线观看| 国产午夜精品久久精品电影| 国产精品无码无卡在线观看久| 精品一区二区三区在线观看l| 一本之道高清乱码少妇| 亚洲国产AⅤ精品一区二区不卡| 起碰免费公开97在线视频| 在线无码国产精品亚洲а∨| 黄又色又污又爽又高潮| 亚洲色大成成人网站久久| 亚洲女人的天堂在线观看| 无卡国产精品| 视频一区二区三区在线视频| 国内丰满少妇一A级毛片视频|