{"created":"2023-07-25T11:05:36.380085+00:00","id":8918,"links":{},"metadata":{"_buckets":{"deposit":"66fb91a1-4599-46c0-9a51-3cf4f35487df"},"_deposit":{"created_by":4,"id":"8918","owners":[4],"pid":{"revision_id":0,"type":"depid","value":"8918"},"status":"published"},"_oai":{"id":"oai:nipr.repo.nii.ac.jp:00008918","sets":["1259:906:1235:1113"]},"author_link":["15675","15677"],"item_1_alternative_title_5":{"attribute_name":"論文名よみ","attribute_value_mlt":[{"subitem_alternative_title":"チキュウジバ ノ ゲンショウ ニ トモナウ カンキョウ ヘンドウ ブラジル ジキ イジョウタイ ニオケル カンソク ノ ヒツヨウセイ"}]},"item_1_biblio_info_14":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"1996-03","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"1","bibliographicPageEnd":"24","bibliographicPageStart":"15","bibliographicVolumeNumber":"40","bibliographic_titles":[{"bibliographic_title":"南極資料"},{"bibliographic_title":"Antarctic Record","bibliographic_titleLang":"en"}]}]},"item_1_creator_6":{"attribute_name":"著者名(日)","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"巻田, 和男"},{"creatorName":"マキタ, カズオ","creatorNameLang":"ja-Kana"}],"nameIdentifiers":[{}]}]},"item_1_creator_8":{"attribute_name":"著者名(英)","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Makita, Kazuo","creatorNameLang":"en"}],"nameIdentifiers":[{}]}]},"item_1_description_1":{"attribute_name":"ページ属性","attribute_value_mlt":[{"subitem_description":"P(論文)","subitem_description_type":"Other"}]},"item_1_description_11":{"attribute_name":"抄録(日)","attribute_value_mlt":[{"subitem_description":"最近の地球磁気の研究によると, 地球磁場はこの1000年間に急速に減少しており, もし今の減少速度で減り続けると, あと1000年ほどで地球磁場がなくなってしまうと言われている。注目すべき点は, 南アメリカ周辺部において, 地球磁場の減少速度が特に著しいということである。この地域は南大西洋磁気異常帯として知られているように, もともと磁場強度が大変弱い所であるため, 今の減少速度で推移すると, この地域の磁場はあと400年余りで消失してしまう状況にある。ところで, 地球磁場はこれまで何回となく磁場反転を繰り返してきたわけであるが, 近い将来, 人類は大変弱い磁場環境におかれることが予想され, 更には, 地球磁場反転の場面に遭遇する可能性も考えられる。他方, 最近の人工衛星観測によると, 地球磁場が大変弱いブラジル周辺部において, 多量の高エネルギー粒子(数MeV以上の電子及び陽子)の入射が見られることが報告されている。これらの粒子は高度数十キロメートル付近まで降下し, X線を放射していることも知られている。今後, 地球磁場の減少が続くとすれば, これらの現象がますます顕著になっていくと予想される。ただ, これらの高エネルギー粒子やX線は厚い大気に阻まれ, 地上までは到達していないため, 地上の生態系に大きな影響を与えていないと思われる。しかしながら, 超高層大気中において, これらの高エネルギー粒子が様々な電磁現象(電磁波の発生や電子密度の変動等)を引き起こしていることが考えられる。また, 最近の観測では, 高エネルギー粒子の入射がオゾン層破壊を引き起こしているという報告もある。これらの状況より, 本研究は, すでに著しく磁場強度の弱いブラジル域において, 超高層大気の現状を調査することにより, 近い将来, 地球磁場が大変弱くなった状況下における地球環境を予測することを目的としている。","subitem_description_type":"Other"}]},"item_1_description_12":{"attribute_name":"抄録(英)","attribute_value_mlt":[{"subitem_description":"According to recent research on rock magnetism, the geomagnetic field intensity of our planet has been monotonically decreasing for one thousand years and it will disappear after another 1000years if the present decreasing rate continues. It should be noted that the decreasing rate of the geomagnetic field near South America has been remarkably large. Since the total intensity of the geomagnetic field in this region is already very weak, the geomagnetic field near South America will disappear within 400years. It is well known that earth magnetic poles have been frequently reversed during the long earth history. When the earth magnetic poles reverse, the intensity of the geomagnetic field becomes very weak. Therefore, it is considered that human beings will have to live under an extremely weak geomagnetic field in the future. From particle observations by satellite, a large quantity of radiation belt particles (>MeV) are precipitating into Brazilian area on account of the very weak geomagnetic field. These high energy particles, precipitating to a few tens of kilometers altitude, are radiating X-rays. If the decrease of the geomagnetic field continues, these particle precipitations will increase and the area of such phenomena will expand near the future. Fortunately, these particles and X-rays do not reach the ground because they are absorbed by the atmosphere. However, there may be a possibility that several electro-magnetic waves occurring in the upper atmosphere reach the ground. Furthermore, it is reported that high energetic solar protons induce the destruction of the ozone layer in the polar cap. So these precipitating particles may also influence the depletion of ozone in the Brazilian anomaly region. The objective of our study is to examine the future earth's environment when the geomagnetic field becomes very weak. We can predict the future earth environment by investigating the upper atmosphere phenomena in the Brazilian region because the geomagnetic field intensity in Brazil is already extremely weak.","subitem_description_type":"Other"}]},"item_1_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.15094/00008918","subitem_identifier_reg_type":"JaLC"}]},"item_1_source_id_13":{"attribute_name":"雑誌書誌ID","attribute_value_mlt":[{"subitem_source_identifier":"AN00181831","subitem_source_identifier_type":"NCID"}]},"item_1_source_id_20":{"attribute_name":"ISSN","attribute_value_mlt":[{"subitem_source_identifier":"00857289","subitem_source_identifier_type":"ISSN"}]},"item_1_subject_21":{"attribute_name":"国際十進分類法","attribute_value_mlt":[{"subitem_subject":"551.510.535/.537","subitem_subject_scheme":"UDC"}]},"item_1_text_10":{"attribute_name":"著者所属(英)","attribute_value_mlt":[{"subitem_text_language":"en","subitem_text_value":"Takushoku University"}]},"item_1_text_9":{"attribute_name":"著者所属(日)","attribute_value_mlt":[{"subitem_text_value":"拓殖大学工学部"}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"1996-03-01"}],"displaytype":"detail","filename":"KJ00000140254.pdf","filesize":[{"value":"404.9 kB"}],"format":"application/pdf","licensetype":"license_6","mimetype":"application/pdf","url":{"label":"KJ00000140254","url":"https://nipr.repo.nii.ac.jp/record/8918/files/KJ00000140254.pdf"},"version_id":"34d39df4-4389-4dcb-bba6-43e83d9a1105"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"departmental bulletin paper","resourceuri":"http://purl.org/coar/resource_type/c_6501"}]},"item_title":"地球磁場の減少に伴う環境変動─ブラジル磁気異常帯における観測の必要性─","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"地球磁場の減少に伴う環境変動─ブラジル磁気異常帯における観測の必要性─"},{"subitem_title":"Change of earth environment due to the decreasing geomagnetic field -The necessity of observation in Brazilian geomagnetic anomaly region-","subitem_title_language":"en"}]},"item_type_id":"1","owner":"4","path":["1113"],"pubdate":{"attribute_name":"公開日","attribute_value":"1996-03-01"},"publish_date":"1996-03-01","publish_status":"0","recid":"8918","relation_version_is_last":true,"title":["地球磁場の減少に伴う環境変動─ブラジル磁気異常帯における観測の必要性─"],"weko_creator_id":"4","weko_shared_id":4},"updated":"2023-07-25T13:12:11.876770+00:00"}