دانلود ترجمه مقاله سونامی ۲۰۱۱ در توهوکو ژاپن

فهرست مطالب:

مقدمه
منبع سونامی
سونامی در ژاپن
شهر ماتسوشیما
رسوبات و گل ولای سونامی
سونامی در حوضه اقیانوس آرام
پیشنهاداتی برای تحقیقات آینده
۱:ارزیابی خطر
۲:محدودیت های نقشه های خطرات منتشر شده
۳:اطلاعات هشدار رسمی
۴:اهمیت و کارایی علائم طغیان
۵:وابستگی به ساختمان های تخلیه
۶ کارایی موج شکن ها به عنوان وسیله کاهش خطر
۷ احساس خطر

بخشی از ترجمه:

 طی این سفر تحقیقاتی و دیگر ممیزی های میدانی در میان مردم برخی مصاحبه ها انجام شدطوری که نشان داده شد که آنها هیچ گونه احساس خطری نکردند. ممیزی NHK از افراد جان سالم به در برده از سونامی نشان داد که نیمی از آنها اصلا فکر نمی کردند در منطقه خطر طغیان باشند(سوگی موتو ۲۰۱۱). از نظر تعداد زیادی از افراد، زلزله ها نه تنها باعث پناه گرفتن افراد در مناطق مرتفع نشدند بلکه باعث ترغیب افراد به سمت مناطق خطر گردیدند. برای تخلیه شهر و ساختمان بسیاری از افراد متکی به ماشین بودند. این می تواند باعث تشدید شرایطی شود که ما بخواهیم عوامل موثر بر ترافیک شهری و انسانی را که مانع از سهولت کار می شوند ارزیابی کنیم(ژاپن تایکز ۲۰۱۱). احتمالا یک سری از فاکتورها در کاهش خطر نقش مهمی دارند:ایمنی موج شکن ها و دیواره ها،رویداد های قبلی سونامی که خسارت زیادی نداشته اند(هشدارها برای زلزله شیلی ۲۰۱۰ و پس لرزه ۹ مارس). تفسیر غلط و سوء تفاهم از هشدار های سونامی و نامناسب بودن بودن فعالیت های آموزشی برای مردم.
در خارج از ژاپن، احساس خطر در میان مردم ایجاد مشکل کرده است. اگرچه تلاش ها تخلیه سازی در ساحل غربی ایالت متحده بسیار موفقیت آمیزتر از گذشته بوده اند(دنگلر و هکاران ۲۰۱۱) طیف وسیعی از مردم به سواحل برای دیدن واقعه میروند. از این رو این می تواندبرای درک پیام های هشدار دهنده به خصوص برای جوامع غیر انگلیسی زبان مشکل آفرین باشد(ویلسون و همکاران ۲۰۱۱). پژوهش های با اولویت مهم به بررسی تاثیرات اصلی و اولیه بر احساس خطر در میان مردم و چگونگی این احساس خطر ها بر رفتار تخلیه تاثیر می گذارند می پردازند.

بخشی از مقاله انگلیسی:

The Tsunami Source The March 11 earthquake ruptured an area roughly 300 km long and 200 km wide on the boundary between the subducting Pacific plate and the overriding North American plate (USGS, 2011). This region of Japan has a well-documented history of earthquakes, including at least 32 ranging from 7 to mid-magnitude 8 since 1900 (NGDC, 2011). The Tohoku sequence began on March 9 with a magnitude 7.3 earthquake that was widely felt. The Japan Meteorological Agency (JMA) issued a tsunami warning for the Miyagi and Iwate coasts, projecting water heights of 3 m. Tide gauges recorded a 0.5-m tsunami in Ofunato, but no damage was reported. The main shock initiated about 43 km WSW of the March 9 foreshock. The initial zone of rupture was downdip of the hypocenter (Figure 2, yellow area) and was characterized by normal rupture velocities and moderate slip (Kanamori, 2011). It produced strong ground shaking in much of the Tohoku region. After about 75 seconds, the rupture moved updip of the hypocenter into the much weaker rocks of the megathrust accretionary prism. This rupture (Figure 2, pink area) was characteristic of a “tsunami earthquake”: relatively slow rupture velocity with weak ground shaking and very large slip. Some models (Ozawa et al., 2011; Pollitz et al., 2011) suggest the peak slip may have exceeded 50 m in some areas of this zone. This second phase of the earthquake likely accounted for the majority of the tsunami generation. Elastic rebound associated with the rupture produced permanent changes in the land surface. Japan’s dense network of GPS instruments documented both horiFigure 3. Left: vertical displacement field of the Tohoku earthquake from GPS measurements provided by the Geospatial Institute of Japan (2011). All coastal areas from Iwate to Chiba subsided during the earthquake. In this preliminary map, the peak vertical displacement (1.2 m) was in the Oshika district of Miyagi Prefecture near Onagawa City. Right: Google Earth images taken before and after the earthquake show the impacts of subsidence at Ishinomaki. Figure 2. Source characteristics of the March 11 earthquake. Left: March 11 epicenter and rupture area. Also shown is the aftershock region and the source areas of previous historical earthquake (adapted from Kanamori, 2011). Right: simplified cartoon of the rupture sequence and tsunami generation. Yellow zone shows the initial rupture downdip of the epicenter (2). After about 75 seconds, the rupture migrated updip of the epicenter (pink zone). The second phase of rupture propagated slowly and produced very large slip (3). 3 EERI Special Earthquake Report — November 2011 zontal and vertical changes (Grapenthin and Freymueller, 2011). There was subsidence along the Tohoku coast after the earthquake, with some areas dropping down more than a meter (Figure 3a). As a result, some low-lying areas are now below sea level (Figure 3b) and parts of the region are more susceptible to tsunami inundation. The Tsunami in Japan Over 5,400 water level measurements have been collected along 2,000 km of the Japanese coastline as of the time of this report (Tohoku Earthquake Tsunami Joint Survey Group, 2011), making this the largest collection of tsunami height measurements for a single tsunami event. The data have been summarized in reports of the IOC/ UNESCO intergovernmental commission on tsunamis (2011) and have also been posted at NOAA’s National Geophysical Data Center (NGDC) Tsunami Data Base (2011). Figure 4 shows the NGDC water height compilation. The highest water levels (38.9 m) at Aneyoshi Bay south of Miyako City in Iwate Prefecture were the maximum ever measured in a Japan tsunami. Water heights were close to or exceeded 20 m in most populated coastal communities in Iwate and northern Miyagi prefectures. On the broad plain that characterizes the coast of Miyagi Prefecture south of Sendai, peak water heights averaged 8-10 m. There were significant tsunami impacts as far south as Chiba Prefecture. Table 1 summarizes the characteristics of the tsunami at selected locations along the Tohoku coast, with data from IOC/UNESCO bulletins (2011), the NGDC, and Mori et al., 2011. Although peak water heights are higher in Iwate and northern Miyagi Prefectures, the inundation areas are smaller, as the coast is rugged and inundation is limited to the low areas near river mouths. In most coastal communities, the Figure 4. Measured tsunami water heights as a function of latitude from post-tsunami surveys, as compiled by the NGDC (2011). The gap in measurement in Fukushima Prefecture is due to access restrictions associated with the Fukushima Dai-ichi nuclear power plant (shown by the x). Table 1. Tsunami Characteristics and Impacts at Selected Locations * Totals included in the Sendai numbers (source: summarized from IOC/UNESCO bulletins). 4 EERI Special Earthquake Report — November 2011 dense city and town centers were very vulnerable, though much of the town or city land area was outside of the inundation zone on the hill slopes and farther inland. Communities on the low-lying areas of the Sendai plain, such as Wakabayashi and Yuriage in Natori City, had little higher ground, and a larger percentage of these communities was flooded. The amount of time between the earthquake and the arrival of significant surges varied along the Tohoku coast. The tide gauges show the first tsunami wave arriving 36 minutes after the earthquake at Hachinohe and 29 minutes post-quake in Okai Town in Chiba Prefecture. A webcam at the Sendai Airport in Natori City showed water arriving at 3:37 p.m., and the generators ceased to function at 4 p.m. This agrees with a series of time-stamped photographs in the Yuriage area of Natori City (see Figure 17) that show peak flooding at 4:11 p.m. Generators at the Fukushima DaiIchi Nuclear Plant stopped at 3:41 p.m., 55 minutes after the earthquake. Eyewitnesses in Northern Miyagi and Southern Iwate Prefectures generally reported 25-30 minutes between the earthquake and the tsunami. A time-stamped photo taken from the top of the Minamisanriku Disaster Management Building shows the structure fully engulfed at 3:35 p.m., 48 minutes after the earthquake. Analysis of the voluminous set of photographs and video imagery taken of the tsunami, and more detailed study of tide gauge recordings, should provide better constraints on the time of arrival. The impact of the tsunami on populated areas of the Tohoku coast was strongly dependent upon the local setting.