Pub Date : 2012-01-01DOI: 10.2467/mripapers1950.28.3_105
Masako Momiyama-Sakamoto, K. Katayama, Nobuko Hashiya, Tokiko Sato
With the turn of the 1970's, the seasonal variation of Japanese mortality, early infant mortality in particular, has undergone conspicuous changes as reported previously. The present report presents what changes the UK and the USA also have shown in total mortality in comparison with Japan, and what might well be responsible for the different changes in recent deaths in the three advanced countries. In total mortality, the UK shows predominant concentration in the cold months, while the USA has come to show such moderateness as to be called desceasonality i. e. a seasonal variation pattern nearly equal to a straight line. Japan herself stands in an intermediate position with a high peak in winter and a small hill in summer. In cerebrovscular mortality, deaths are considerably concentrated in winter in Japan and the UK but conspicuously moderate as a whole in the USA. In infant mortality, signs of deseasonality are increasing in the USA and Japan, but there are noteworthy differences between the two nations : a bimodal curve is seen in Japan whereas ups in JanuaryFebruary and in April-June and a trough from July to September are witnessed in the USA seasonal variation pattern. The marked lowering and the increasing deseasonality of mortality in recent years in Japan are ascribed in the final analysis to the high-rate industrial growth and the subsequent urbanization of Japanese society with better living conditions and improved medical services. As for the UK, sanitary conditions had surprisingly improved as early as the middle of the nineteenth century and the representative seasonal variation pattern came to the fore earliest in the world and remained stabilized for a long span of time, and in the 1970's, no marked changes came to appear as compared with the increasing deseasonality in the USA and the mounting signs of deseasonality in Japan hitherto regarded as 25-30 years behind the USA. The USA is a vast country including high latitudes and subtropical areas and calls for regional analysis in the southern states generally less advanced than other industrial areas, deaths, infant mortality in particular, are surprisingly concentrated in the cold months in contrast to the general deseasonal pattern in many northern states and remain quite unchanged in the 1960's and 1970's. An international comparison of the seasonal disease calendars finally reveals that Japan in the 1970's shows noteworthy changes compared with the 1930's and 1950's, while no such noticeable changes are seen in the UK and the USA.
{"title":"Seasonality in Recent Mortality in Japan, UK and USA","authors":"Masako Momiyama-Sakamoto, K. Katayama, Nobuko Hashiya, Tokiko Sato","doi":"10.2467/mripapers1950.28.3_105","DOIUrl":"https://doi.org/10.2467/mripapers1950.28.3_105","url":null,"abstract":"With the turn of the 1970's, the seasonal variation of Japanese mortality, early infant mortality in particular, has undergone conspicuous changes as reported previously. The present report presents what changes the UK and the USA also have shown in total mortality in comparison with Japan, and what might well be responsible for the different changes in recent deaths in the three advanced countries. In total mortality, the UK shows predominant concentration in the cold months, while the USA has come to show such moderateness as to be called desceasonality i. e. a seasonal variation pattern nearly equal to a straight line. Japan herself stands in an intermediate position with a high peak in winter and a small hill in summer. In cerebrovscular mortality, deaths are considerably concentrated in winter in Japan and the UK but conspicuously moderate as a whole in the USA. In infant mortality, signs of deseasonality are increasing in the USA and Japan, but there are noteworthy differences between the two nations : a bimodal curve is seen in Japan whereas ups in JanuaryFebruary and in April-June and a trough from July to September are witnessed in the USA seasonal variation pattern. The marked lowering and the increasing deseasonality of mortality in recent years in Japan are ascribed in the final analysis to the high-rate industrial growth and the subsequent urbanization of Japanese society with better living conditions and improved medical services. As for the UK, sanitary conditions had surprisingly improved as early as the middle of the nineteenth century and the representative seasonal variation pattern came to the fore earliest in the world and remained stabilized for a long span of time, and in the 1970's, no marked changes came to appear as compared with the increasing deseasonality in the USA and the mounting signs of deseasonality in Japan hitherto regarded as 25-30 years behind the USA. The USA is a vast country including high latitudes and subtropical areas and calls for regional analysis in the southern states generally less advanced than other industrial areas, deaths, infant mortality in particular, are surprisingly concentrated in the cold months in contrast to the general deseasonal pattern in many northern states and remain quite unchanged in the 1960's and 1970's. An international comparison of the seasonal disease calendars finally reveals that Japan in the 1970's shows noteworthy changes compared with the 1930's and 1950's, while no such noticeable changes are seen in the UK and the USA.","PeriodicalId":39821,"journal":{"name":"Papers in Meteorology and Geophysics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69032534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Atmospheric CO2 and O3 observed on Rishiri Island from December 2006 to March 2007","authors":"H. Inoue, Y. Fukazawa, H. Tanimoto, H. Matsueda, Y. Sawa, A. Wada","doi":"10.2467/MRIPAPERS.59.31","DOIUrl":"https://doi.org/10.2467/MRIPAPERS.59.31","url":null,"abstract":"2006年12月から2007年3月まで北海道利尻島(45°07′N, 141°12′E)において大気中CO2とO3の濃度測定を実施した。観測されたCO2とO3濃度は数分から数ヶ月の時間スケールで変動しており、12月から2月中旬までの期間CO2濃度はO3濃度の変動と逆相関を示した。この逆相関はユーラシア大陸の高緯度地域及び利尻島での土壌呼吸によるCO2排出と地表でのO3分解消失によって引き起こされるものと考えられた。12月から2月中旬までの逆相関とは対照的に、2月中旬以降大気中CO2濃度とO3濃度は、時折正相関を示した。これら高濃度のCO2とO3は日本及び朝鮮半島の人為起源による排出・輸送の影響を受けていることが示唆された。","PeriodicalId":39821,"journal":{"name":"Papers in Meteorology and Geophysics","volume":"59 1","pages":"31-38"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69025475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Akira Yamazaki, S. Aoki, Y. Yoshida, Akio Kobayashi, A. Katsumata, M. Abe, Ken Moriwaki, N. Okawara, Y. Osada, Hidetoshi Matsuoka, T. Yoshida, Hiroshi Sekitani, Kohji Niinou, Hideyuki Hiramatsu
{"title":"Aftershock Observation of the 2004 off the Kii Peninsula Earthquake Using Ocean Bottom Seismometers","authors":"Akira Yamazaki, S. Aoki, Y. Yoshida, Akio Kobayashi, A. Katsumata, M. Abe, Ken Moriwaki, N. Okawara, Y. Osada, Hidetoshi Matsuoka, T. Yoshida, Hiroshi Sekitani, Kohji Niinou, Hideyuki Hiramatsu","doi":"10.2467/MRIPAPERS.59.65","DOIUrl":"https://doi.org/10.2467/MRIPAPERS.59.65","url":null,"abstract":"2004年9月5日に紀伊半島南東沖で発生した地震（Mj7.4）は南海トラフ軸付近で発生した津波を伴う大地震である。この地震の発震機構は南北方向に圧縮軸を持つ逆断層型で、フィリピン海プレート内あるいは上部マントルで発生したものと解釈されている。我々はこの地震の詳細な余震分布とその時空間推移を調査するため、自己浮上式海底地震計（OBS）による余震観測を実施した。余震観測は2004年9月から2005年8月までの期間、断続的に3回にわたって実施された。震源決定に用いた1次元P波の速度構造はOBSの観測海域で実施された速度構造探査結果を参照して求めた。また震源の決定精度を向上させるため、PS変換波を用いた堆積層補正をおこなった。その結果、気象庁一元化震源に比べ詳細かつ高精度な余震分布を得ることができた。OBS観測から求めた余震の震源は気象庁一元化震源と比較すると、深さは20kmほど浅く5～30kmに分布し、震央については全体的に南東方向に10kmほどシフトした。気象庁一元化震源では余震活動は主にトラフ軸より陸側に分布するように見えていたが、主たる余震活動はトラフ軸沿いで発生していることがわかった。また、余震活動は深さ5～10 kmの比較的浅い地震群と、深さ15～30kmの比較的深い地震群の2群に分かれていることが見出された。前者は余震域の中央部から北部にかけてのフィリピン海プレート内およびその上部の付加体内で発生しており、後者は前震および本震の破壊域と思われる海溝軸下の上部マントルで発生していることがわかった。さらに、浅い地震群の中にいくつかの地震クラスターが見出された。これらの地震クラスターは付加体からフィリピン海プレート内までほぼ鉛直に下降しているとみられる。これら余震域の中で発見された地震クラスターは、超低周波地震の発生源となっている付加体の分岐断層との関係において興味が持たれる。","PeriodicalId":39821,"journal":{"name":"Papers in Meteorology and Geophysics","volume":"59 1","pages":"65-82"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69025588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Statistical Relationship between Tsunami Maximum Amplitudes of Offshore and Coastal Stations","authors":"H. Takayama","doi":"10.2467/MRIPAPERS.59.83","DOIUrl":"https://doi.org/10.2467/MRIPAPERS.59.83","url":null,"abstract":"地震発生直後に地震データを用いて推定された震源の位置と規模に基づく現行の津波予報では津波地震の場合には過小評価となる。実際に沖合で観測された津波波高データを活用することによって、沿岸での津波波高をより適切に予測できる可能性があると考えられる。気象庁の東海沖、房総沖、海洋研究開発機構の室戸沖のケーブル式海底地震観測システムに設置された圧力計を用いた海底津波計データから時間領域でのフィルタ処理によって津波成分を抽出した。これによって得られた沖合の津波計による津波波高を沿岸の検潮所での津波波高と比較し、その統計的関係を調べた。震央距離による補正を行うか否か、振幅あるいは震央距離の関数と仮定するか否かの場合について、AICを使って最も良い回帰モデルを得た。","PeriodicalId":39821,"journal":{"name":"Papers in Meteorology and Geophysics","volume":"4 1","pages":"83-95"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69025266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hydrothermal Activity Inferred from Comprehensive Observation of Unrest in Adatara Volcano","authors":"Tetsuya Yamamoto, A. Takagi, K. Fukui, T. Owada","doi":"10.2467/MRIPAPERS.59.39","DOIUrl":"https://doi.org/10.2467/MRIPAPERS.59.39","url":null,"abstract":"安達太良山沼ノ平火口では1996年頃から熱泥噴出など火山活動活発化の傾向が見られたが、地震活動には明瞭な変化がなかった。火山活動を捉えるために、沼ノ平火口付近で地磁気、GPS、重力、自然電位の観測を行った。地磁気観測では累積で最大110nTにおよぶ顕著な全磁力変化が観測された。観測された地磁気変化から、1997年から2000年頃までは火口底南東部の温度上昇による消磁が、2000年以降は火口底北東部の温度低下による帯磁が進行したことが推定された。GPSによる地殻変動観測からは、2000年頃まで火口付近の膨張と、その後の収縮が観測された。重力観測では観測点の標高変化の影響を評価できるように、重力観測点におけるGPS観測を並行して行った。2001年から2005年にかけて沼ノ平で重力の増加が観測され、その変化は観測点の標高変化で期待される変化よりも大きかった。火山活動に伴う地下水の変動を反映したものと推定される。自然電位連続観測では、銅・硫酸銅平衡電極によってキャリブレーションを行うことで長期的安定性を維持し、また観測点の地中温度を観測することで電極電位の温度補正をする手法を用いた。この手法によって、小規模な熱水活動によるとみられる変化を捉えた。実施したこれらの観測から、沼ノ平火口の火山活動は2000年頃まで比較的活発な状態であったが、その後低下したとみられる。観測された火山活動は熱水の動きに密接に結びついているとみられるため、深部から熱水の供給を受けたとき地下水の流れや温度分布がどのように変化するかを熱水シミュレーションで調べた。沼ノ平火口付近の地下の固有透過度をモデル化し、様々なケースについて計算を行った結果、地磁気観測から推定されるような温度変化を説明するには、南北2箇所の熱水供給源が必要であることが明らかになった。また、熱水シミュレーションの結果から、地磁気変化や重力変化を定量的に求めたところ、それらは観測と調和的だった。安達太良山のように地震観測で火山活動が捉えにくい火山では、地磁気、重力、自然電位、火口付近のGPS観測などの総合的な観測を熱水シミュレーションと組み合わせて用いることが、火山活動を包括的に把握する有力な手法である。","PeriodicalId":39821,"journal":{"name":"Papers in Meteorology and Geophysics","volume":"59 1","pages":"39-64"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69025490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The evolution of Typhoon Tokage (0423), which made landfall in western Japan and underwent extratropical tran sition (ET) in October 2004 associated with strong winds and heavy rainfall on both the right and left sides of the storm track, is diagnosed using a gridded regional analysis (RANAL) data set produced by the Japan Meteorological Agency. When Tokage makes landfall, it is located in the right entrance of an upper-tropospheric jet streak and downstream of a synoptic-scale upper trough. The lack of an intense short-wave trough interacting with Tokage is consistent with the fact that the storm did not reintensify after the completion of ET. The strong cyclonic circulation in the lower troposphere associated with Tokage strengthens a preexisting lower-tropospheric front over western Japan, and Tokage eventually transformed into a frontal cyclone in the baroclinic zone. The conditional symmetric instability related to the approach of Tokage to the upper-tropospheric jet stream, as well as the conditional instability in the lower-tropospheric air on the cooler side of the frontal zone over the warm sea surface of the southern Sea of Japan, are considered to contribute to the heavy precipitation along the northern coast of western Japan, which is located on the left side of the storm track. Further study is needed to clarify the impact of air–sea interaction on the intensity and structure of a tropical cyclone in the midlatitude.
{"title":"Extratropical Transition of Typhoon Tokage (0423) and Associated Heavy Rainfall on the Left Side of Its Track over Western Japan","authors":"N. Kitabatake","doi":"10.2467/mripapers.59.97","DOIUrl":"https://doi.org/10.2467/mripapers.59.97","url":null,"abstract":"The evolution of Typhoon Tokage (0423), which made landfall in western Japan and underwent extratropical tran sition (ET) in October 2004 associated with strong winds and heavy rainfall on both the right and left sides of the storm track, is diagnosed using a gridded regional analysis (RANAL) data set produced by the Japan Meteorological Agency. When Tokage makes landfall, it is located in the right entrance of an upper-tropospheric jet streak and downstream of a synoptic-scale upper trough. The lack of an intense short-wave trough interacting with Tokage is consistent with the fact that the storm did not reintensify after the completion of ET. The strong cyclonic circulation in the lower troposphere associated with Tokage strengthens a preexisting lower-tropospheric front over western Japan, and Tokage eventually transformed into a frontal cyclone in the baroclinic zone. The conditional symmetric instability related to the approach of Tokage to the upper-tropospheric jet stream, as well as the conditional instability in the lower-tropospheric air on the cooler side of the frontal zone over the warm sea surface of the southern Sea of Japan, are considered to contribute to the heavy precipitation along the northern coast of western Japan, which is located on the left side of the storm track. Further study is needed to clarify the impact of air–sea interaction on the intensity and structure of a tropical cyclone in the midlatitude.","PeriodicalId":39821,"journal":{"name":"Papers in Meteorology and Geophysics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69025817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of atmospheric CO2 measurements from new flask air sampling of JAL airliner observations","authors":"H. Matsueda, T. Machida, Y. Sawa, Y. Nakagawa, K. Hirotani, Hajime Ikeda, Naoto Kondo, K. Goto","doi":"10.2467/MRIPAPERS.59.1","DOIUrl":"https://doi.org/10.2467/MRIPAPERS.59.1","url":null,"abstract":"2005年12月以降、新しい空気採取装置（ASE）を利用して、オーストラリアと日本を結ぶJALの旅客機によって西部太平洋上の高度約10kmにおける大気中二酸化炭素(CO2)の測定結果を収集した。ASEで観測されたCO2は、同じフライトで観測した二酸化炭素連続測定装置（CME）の結果と非常に良く一致していた。また、ASEのデータは高時間分解能を持つCMEのデータに比べて観測密度が粗いが、両データとも、北緯30度から南緯30度までを5度間隔で分割した緯度帯平均のCO2濃度は、近い値を示した。JAL旅客機による新旧観測において一貫したデータセットを作成するために、気象研究所と国立環境研究所で使用しているCO2標準ガスのスケールを比較した。新観測で得られたCO2のデータには明瞭な季節変化と増加傾向が見られ、それらは、過去12年間の旧観測で得られたCO2変動の気候値の外挿から再現された変動とほぼ一致していた。特に、新観測において、長期的トレンドを除去した季節変動の緯度帯変化は、旧観測の気候値から得られるものと極めて良く類似していた。これらの結果から、JAL旅客機による新旧の観測データが一貫した連続性を保っていることが示された。","PeriodicalId":39821,"journal":{"name":"Papers in Meteorology and Geophysics","volume":"59 1","pages":"1-17"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69025408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Surface Displacement by Spherical Pressure Sources of relatively Large Radius compared with Those Depth","authors":"T. Sakai, Tetsuya Yamamoto, K. Fukui, Kenji Fujiwara, A. Takagi, M. Churei","doi":"10.2467/MRIPAPERS.58.17","DOIUrl":"https://doi.org/10.2467/MRIPAPERS.58.17","url":null,"abstract":"火山における地殻変動を解釈するモデルとして、従来、山川（1955）の解析解に基づく「茂木-山川モデル」（または、単に「茂木モデル」）が多く用いられてきた。山川の解は、深さに対して充分小さな球圧力源が半無限均質弾性体内に存在するという、限定された条件下においてのみ成立する解であるが、球圧力源の深さDに対する半径aがどの程度の場合まで山川の解が精度良く成立するのかについては、定量的な検証はこれまでほとんどなされていない。一方、McTigue（1987）による解析解は、山川の解をa/Dが大きい場合にも適用できるよう修正したものであるが、この解についても山川の解と同様、適用限界についての定量的な検証はこれまで行われていない。そこで、本研究では、有限要素法（FEM）を用いてa/Dが大きなモデルを作成し、地表面変位の数値解を求め、２つの解析解との比較を行った。その結果、２つの解析解の適用限界が明らかとなった。例えば、FE解析結果に1％以内で一致するa/D の値は、山川の解で0.22，McTigueの解で0.45であることが判明した。a/Dがこれらの値より小さな場合には、２つの解析解は充分精度良く成立すると言えよう。a/D がこれより大きくなると、２つの解析解とFE解析結果との食い違いは次第に顕著になっていく。一方、FE解析結果に山川の解を適用してDおよびaを決定すると、a/D が大きくなった場合、Dは真の値よりも過剰に浅く決定されるが、aは真の値に比較的近い値に決定され、従って、圧力源の体積変化量ΔVも比較的正確に見積もることができる。","PeriodicalId":39821,"journal":{"name":"Papers in Meteorology and Geophysics","volume":"58 1","pages":"17-30"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69025037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-01-01DOI: 10.2467/mripapers.58.135
N. Kitabatake, S. Hoshino, K. Bessho, F. Fujibe
Typhoon Songda (0418), which damaged much of the Japan Islands with strong winds, underwent extratropical transition (ET) and reintensified while it moved northeastward in the Sea of Japan. The features associated with Songda during ET are investigated by using data of various satellite-borne sensors. The interaction of the cyclone with the midlatitude environment is also diagnosed and discussed by using the gridded dataset of regional analysis (RANAL) produced by the Japan Meteorological Agency. The satellite observations reveals dissipation of the eyewall, formation of a convective rainband accompanied by warm frontogenesis, and some features characteristic of a wind field around a tropical cyclone undergoing ET, e.g., a “horseshoe” gale/storm-force winds shape and an axis of minimum winds extending northeastward from the cyclone center. The satellite data also suggest that a disturbance that originates in the upper tropospheric westerly interacts with the tropical cyclone at the ET stage. The representation of Songda in RANAL is generally consistent with the satellite observations. Diagnoses of upper-tropospheric flows and the quasi-geostrophic omega equation suggest baroclinic development of Songda due to its interaction with a disturbance that originates in the upper troposphere in the midlatitude westerly. Finally it is pointed out that the interaction between the tropical cyclone and the baroclinic disturbance may cause ambiguity of the cyclone center.
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