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The author:(作者)归海一刀published in(发表于) 2014/3/25 23:04:38 CAs detailed satellite monitoring buoy： position confirm the wreckage difficult
Summary: South China Sea Institute of Chinese Academy of Sciences on March 24 was released late in South India ocean surface circulation field and drifting buoy tracks the history of the mid-March and speculation.
21st century business Herald investigation using Air France flight 447 plane crash 3 model inversion of ocean currents, as well as a variety of means such as satellite drifting buoy historical trajectory is still empty-handed. Finally found the black box is already two years later.
South China Sea Institute of Chinese Academy of Sciences (hereinafter "Institute of the South China Sea,") on March 24, was released late in South India ocean surface circulation field and drifting buoy tracks the history of the mid-March, and on March 18 by the China "high score first" satellite observations to suspected MH370 of aircraft wreckage location to speculate that may occur on March 8.
CAs key laboratory of tropical South China Sea marine environmental dynamics researcher Du Yan told the 21st century business Herald reporter, "changes in ocean currents are a variety of factors together, very difficult to pinpoint the location of suspected debris."
Eddy current effect position
March 20 Australia Maritime Bureau (Australian Maritime Safety Authority, known as AMSA), a satellite picture shows filmed in March 16, Australia, West of India Southern Ocean found the suspected remains of a length of 24 meters, where the waters with the loss of the aircraft match the channel height on the southern corridor.
On March 22, declared, "high score first," satellite on March 18 from Australia released of suspected locations South West about 120 km south of India Ocean (latitude 44 degrees, 57 minutes, longitude 90 degrees 13 minutes) suspected of floating debris observed, about 22 meters wide and about 13 metres long.
Du Yan believes that Australia and China satellite observation of suspected remains of Malaysian Airlines flight MH370, not the same, "Australia observation of suspected debris in the North West, and China (observation of suspected debris) in the South West as India ocean currents from West to East, and floats for the same kind of unlikely. ”
21st century business Herald reporter pictures published by the South China Sea by Chinese Academy of Sciences found that the Institute has 9 satellite monitoring buoys, their drift tracks after March 18, when China satellite observation of suspected remains of latitude and longitude range. Through GPS satellite buoy system, record buoy trajectories in order to observe a range of sea surface currents and other data tools.
Due to the sea's surface circulation trends from West to East, as well as observing these satellite buoy after moving the track, finally confirmed on March 18 by the CAs South China Sea China satellite observation of suspected debris, on March 8, may appear at the March 18 locations within 50-250 km to the West of, and March 26 are going to be there on March 18, approximately 70-200 miles east of the location.
Du Yan said the India Ocean Mesoscale Eddy is the cause of it is difficult to pinpoint one of the main reasons.
India ocean are stable from West to East of the Antarctic Circumpolar current, but there are multiple Mesoscale eddy currents. In the scale Eddy is marine terminology, its formed causes diverse, like must range within of currents of bent spent big, part currents will has may and matrix currents from, formed a independent of Eddy, formed as Typhoon as, side rotating, side forward movement of local currents, its effects range in 100-200 km Zhijian, will exists days even years, and encountered special terrain Eddy of mobile track will occurred changes.
Du Yan, as the suspected wreckage found where undersea mountains, and this place is South of the westerlies, lack of land or in the mountains, West wind can quickly move without any blocking, making rapid changes of air pressure and temperature and are prone to storms, have significant impact on Eddy current track, so it is difficult to suspect before the wreck's location and where accurate positioning for the future.
Wreckage location confirmation difficult
An unnamed marine researchers believe that if the suspected wreckage was finally confirmed, the information released by the Chinese Academy of Sciences in South China Sea helps verify that aircraft at the end of the sea, which is acknowledgement of the black box location helpful.
However, according to Air France flight 447 crash search for empirical observation, through the ocean passenger data to figure out the final sea locations will not be easy.
To af 447 airliner for cases, ground control Taiwan in each 5 minutes on will received aircraft made back of information, which including aircraft of location, and height, and speed and heading, situation Xia, delineation has aircraft pendant sea of maximum flight radius about for 40 nautical miles (about 17,000 square kilometers), but eventually found body main wreckage and salvage out black box, has is two years zhihou of things.
MH370 lost satellite data is sent 1 hour once before, and that the data does not include the plane's position, altitude, speed and course, current search article search-and-rescue groups designated the North and South corridors, searching an area of more than 300,000 square kilometers.
AMSA reported that Australia C-130 20th of the Navy have dispatched a Royal Air Force Hercules aircraft in the region, dropped a datum marker buoy. These marker buoys can provide information to assist in construction of AMSA's drift model for hydrology. If the positioning of the target task for a long period, these buoys can be sustained reference marks.
Current observation of ocean currents, buoys and satellite microwave remote sensing through satellite two main instruments. Du Yan explains, satellite buoy trajectories show sea surface speeds of around 15 metres deep, more representative of the true speed. And satellite remote sensing imagery are estimates of the average water velocity of the upper ocean, although the trajectory of mesoscale eddy currents can be observed, but because of the upper ocean area larger, velocity is not accurate.
But should the operation of the above two instruments can only be launched on March 16 suspected debris flows for ultimate source to confirm that suspected debris, also need to gather the waters of the sea surface wind speed and direction, solar radiation, precipitation, sea surface heat fluxes and evaporation, tidal, river water flux data in order to establish a more sophisticated analytical models.
As in the main wreckage and the black boxes of Air France flight 447 passenger aircraft search process, survey 3 inversion of ocean current models, and a variety of means such as satellite drifting buoy historical trajectories, still empty-handed. Eventually find the main wreckage and black boxes are Air France 447 crash two years later.
And CAs South China Sea yesterday (March 24) also admits: "appearance of the drifter accurate location, needs the support of circulation information of higher accuracy. But because of the lack of observational data, current circulation with high precision data needs to be obtained through numerical simulation methods. In the area, correct numerical results depend on the Antarctic Circumpolar current, Mesoscale Vortex and accurate simulation of mesoscale eddies. But at the same time meet the simulation and prediction of three scales, is still very difficult. ”
(Original title: difficult to locate the wreckage: CAS detailed satellite monitoring buoys)
核心提示：中国科学院南海海洋研究所3月24日晚间发布了南印度洋3月中旬表层环流场及历史漂流浮标轨迹，并进行了推测。
21世纪经济报道 法航447空难调查方利用3个洋流模型反演方式，以及卫星浮标历史漂流轨迹等多种手段依然空手而归。最终寻找到黑匣子已是两年后。
中国科学院南海海洋研究所(下简称“中科院南海所”)3月24日晚间发布了南印度洋3月中旬表层环流场及历史漂流浮标轨迹，并以此对3月18日被中国“高分一号”卫星观测到的疑似MH370客机残骸在3月8日可能出现的位置进行了推测。
中科院南海所热带海洋环境动力学重点实验室研究员杜岩告诉21世纪经济报道记者，“洋流变化受多种因素共同作用，要对疑似残骸的位置进行准确定位非常困难”。
涡流影响位置确定
3月20日澳大利亚海事局(Australian Maritime Safety Authority，简称AMSA)称，一颗卫星在3月16日拍摄的图片显示，在澳大利亚以西的印度洋南部海域发现的一块疑似残骸长度达24米，所在海域与失联客机的南部走廊的航道高度吻合。
3月22日中国方面宣布，“高分一号”卫星在3月18日，距澳大利亚公布疑似物位置南偏西120公里左右的南印度洋海域(南纬44度57分，东经90度13分)观测到疑似漂浮物，长约22米宽约13米。
杜岩认为澳大利亚和中国的卫星所观测到的马航MH370客机疑似残骸，并非同一个，“澳大利亚观测的疑似残骸在北偏西，而中国(观测到的疑似残骸)在南偏西，由于印度洋的洋流方向为由西向东，因此漂浮物为同一种的可能性不大。”
21世纪经济报道记者通过中科院南海所公布的图片发现，该研究所有9颗可监测的卫星浮标，其漂流轨迹经过了3月18日中国卫星观测到的疑似残骸的经纬度范围。卫星浮标是通过GPS系统，记录浮标的运动轨迹，以对一定范围的海域表层洋流等数据进行观察的工具。
由于该海域的表面环流呈现自西向东趋势，在观察上述卫星浮标的移动轨迹后，中科院南海所最终确认3月18日中国卫星观测到的疑似残骸，在3月8日可能出现在3月18日位置以西50-250公里范围内，而3月26日将可能出现在3月18日位置以东大约70-200公里范围内。
杜岩表示，印度洋的中尺度涡流是导致难以准确定位的主要原因之一。
印度洋是稳定的自西向东的南极绕极流，但其中存在多个中尺度涡流。中尺度涡流是海洋术语，其形成原因多样，比如一定范围内的海流的弯曲度过大，部分海流将有可能与母体海流脱离，形成一个独立的涡流，形成如台风那样，一面旋转，一面向前运动的局部洋流，其影响范围在100-200公里之间，会存在几天甚至几年，而且遇到特殊地形涡流的移动轨迹将发生变化。
杜岩称，由于疑似残骸发现地方，恰好有海底山脉，而且这个地方是南半球的西风带，缺乏陆地或大山，西风可以毫无阻滞地迅速移动，使气压和气温迅速变化，容易产生风暴，也对涡流轨迹影响较大，因此非常难以对疑似残骸之前的位置和未来的去向准确定位。
残骸位置确认难度大
一位匿名海洋研究者认为，若上述疑似残骸最终被确认，则中科院南海所发布的信息有助于确认客机最终的坠海地点，这对于黑匣子位置的确认亦有一定帮助。
但根据法航447客机的搜寻经验观察，通过海洋数据来推测客机最终的坠海位置并非易事。
以法航447客机为例，地面控制台在每5分钟就会收到飞机发回的信息，其中包括飞机的位置、高度、航速和航向等情况下，划定了飞机坠海的最大飞行半径大约为40海里(约1.7万平方公里)，但最终找到机体主要残骸以及打捞出黑匣子，已经是两年之后的事情。
而MH370失联前的卫星数据仅为1小时发送一次，且该数据未包含飞机的位置、高度、航速和航向，目前搜救组划定了南北两条搜寻走廊，搜寻面积超过30万平方公里。
而据AMSA的消息称，澳大利亚海军20日已经派遣一架皇家空军C-130大力神号飞机在该区域投下基准标记浮标。这些标记浮标可以通过提供关于水文运动的信息来协助AMSA构建漂移模型。如果对目标物的定位任务时间较长，这些浮标能成为持续的参考标记。
目前对洋流变化的观察主要通过卫星浮标和卫星微波遥感两个手段。杜岩解释称，卫星浮标轨迹显示的是海洋表层15米深左右的流动速度，更能代表真实速度。而卫星遥感图是对海洋上层的平均水流速度的估算，尽管可以观测到中尺度涡流的轨迹，但是由于海洋上层的范围更大，因此流速并不准确。
但即使运营上述两个手段，也仅可以倒推出3月16日疑似残骸的大致流向，对于疑似残骸的最终来源确认，还需要搜集该海域的海面风速、风向、太阳短波辐射、海面净热通量、降水与蒸发、潮汐、河水通量等数据，以建立更加先进的分析模型。
如在法航447客机主要残骸和黑匣子的寻找过程中，调查方利用3个洋流模型反演方式，以及卫星浮标历史漂流轨迹等多种手段，依然空手而归。最终寻找到法航447客机主要残骸和黑匣子已是两年后。
而中科院南海所在昨日(3月24日)亦承认：“漂流物准确的出现位置，需要更高精度的环流场资料的支持。但由于观测资料的缺乏，目前高精度环流场数据需要通过数值模拟的方法获得。在该海域，正确的数值模拟结果依赖于对南极绕极流、中尺度涡旋以及次中尺度涡的精确模拟。但同时满足这三种尺度的模拟和预报，至今仍然非常困难。”
(原标题:难定位的残骸：中科院详解卫星监测浮标）
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