Ali, Tibet glacier collapse successive scientists dispute whether the series of disasters began

With a great sound, a gust of wind blew, blew the tent along and blows away your Lake Lake by mistake; then, glacier collapse, just for a few minutes, moving downstream is 6 km ice come into Aru wrong Lake, tsunami waves, destroying close to everything.

Avalanche avalanche caused due to climate change of ice, over more than 300 rescue workers were searching for the missing cattle herders. This pictures are @ CCTV

This scene from a disaster movie, occurred on July 17, 2016, the Ali area in Tibet East ru Xiang a rare ice collapses.

According to the Xinhua News Agency and the subsequent statistical scientist team, while hundreds of rescue teams rushed to the rescue for 9 days later, there are still 9 deaths, missing hundreds of yaks, as well as lots of grassland has been damaged. Avalanche formed nearly 10 square kilometers of glaciers in the area of the landslide body, about the size of 1400 football fields, a volume of about 70 million cubic meters.

Shortly thereafter, on September 21, the rare extensive glaciers once again near collapse.

Global warming, which led to many of the glacier retreat, but Ali is an exception, where the Glacier changes slowly over the past decades. Glacier scientists, this avalanche was considered twice upended previous understanding.

Researchers believe that Ali, climate change may be the ice collapsed twice because of "murderer" as temperatures rise and rainfall increases, the two avalanche may only be beginning of a series of avalanche disaster in the future.

Climate change is most likely "the kidnapper"
In a forthcoming study in the journal of glaciology (Journal of Glaciology) in one study, from the Institute of Tibetan plateau research, Ohio State University's Byrd Polar and climate research centre (Byrd Polar and Climate Research Center), among others, researchers believe that Ali, climate change may be the ice collapsed twice because of "murderer" as temperatures rise and rainfall increases, The two avalanche may only be beginning of a series of avalanche disaster in the future, in this regard, the existing science still does not have enough research and preparation.

Ngari is located in northwestern Tibet, and an average altitude of 4500 meters, Himalayas, gangdise, Karakoram lie. Researchers and statistics, Ali has 5,862 glacier, an area of about 4900 square kilometers. These glaciers provide sustainable water sources for the local, but also contains disaster risk.

Monitor displays over the past decades, Ali glacier with temperature low, low accumulation, characterized by the slow, slow flow, researchers considered to be extremely stable glacier. Glacier Ice collapses this year took over the glaciers, which are not recorded in history. Monitoring also shows that the local climate, along with the rise in global temperatures over the past more than 50 years, the local temperature continues to rise.

Analysis of satellite images shows, avalanche snow melting of the Glacier changes began in September 2015. Water penetration and accumulation under the glacier, causing the bottom slide, and upper part of the glacier was stuck in a narrow valley, which may gradually cause the disaster.

Scientists speculate that such Glacier changes associated with global warming, but they still need to do more research. But if the facts were as they suspect it, then Ali icefall glacier disasters may be a new or new way of glacier retreat. They will once again sounded alarm on global climate change.

However, some scholars hold different views.

Chinese Academy of Sciences, state key Lab of Cryosphere Kang shichang, Guo Wanqin, who believe that Ali, the avalanche is not an isolated case, but regions such as Tibet, nyingchi Prefecture, southern GAL Ba Wafeng glacier icefall multiple times due to movement, as in the cases is the periodic movement of the glacier.

Guo Wanqin explained that the known causes of glacier movement is mainly due to the cyclical nature of the glacier caused by instability, outside influences are still not settled.

But the researchers also believe that holding a different view, global warming will inevitably lead to more glacial meltwater into the glacier bed, will change to some extent the development of glacier movement. According to Guo Wanqin laboratory data, the thousands of glaciers in China, about 1% now in the movement phase.

Early warning is still difficult

In addition to the causes of avalanche, avalanche disaster warnings, as researchers focus on new issues.

In fact, scientists have succeeded in warning the Ali of the avalanche for the second time.

After the avalanche for the first time, Tung Yu-Xiang recalled local herders, a few days before the incident, they had heard day and night made that break the sound, but no one is alarmed. Exception after the glacier has caused many scholars note that Switzerland Zurich ETH, Swiss Federal Institute for snow and avalanche expert research institutions such as the Group found in the satellite images, an adjacent glaciers are undergoing similar changes, glaciers shift, with huge cracks appeared between the main glacier. They were immediately warned by email.

In China, it is for the first time the glacier Research Institute of Tibetan plateau research, Chinese Academy of Tian LiDE, who received the news, the finding being communicated to the rutog County in which the incident, the County Government will soon move out of the neighbouring pastoralists, and barred anyone from entering the area.

As the researchers expected, the glaciers took place for the second time, the good news is, as a result of preventive measures, there were no casualties. Tian LiDE later recalled, he was immediately via email to share the news, national researchers are very pleased.

However the prediction of success does not mean early warning mechanisms can be established soon.

Tian LiDE explained that the large glacier is encrypted within continuous monitoring is more difficult, the cost is high. Switzerland Zurich Federal Institute postdoctoral Silvan Leinss was warned one of the experts, he is surging on the news (www.thepaper.CN) says there are many objective conditions avalanche warning, for example, satellites also cannot take the initiative to early warning, it needs the scientist a lot of analysis, in addition, by monitoring by remote sensing, will also meet the clouds and other weather, they will block the view of scientists. "People that climate change is not sufficient. Especially in the face of climate catastrophe may occur, as well as the increasing number of natural disasters due to climate change, scientists and the local government have presented new research topics. "Tian LiDE said.

(Editors: Dou Yuan UN833)
2016-11-24 21:08:50
Surging news

西藏阿里接连冰川崩塌 科学家争议是否系列灾害的开始

　　随着巨大的声响，一阵强风迎面扑来，吹翻了沿线的帐篷，吹走了阿汝错湖岸的湖水；紧接着，冰川崩塌，短短几分钟，向下游移动足有6公里，碎冰接踵而至，冲入阿鲁错湖，出现海啸一般的巨浪，摧毁了邻近的一切。

　　冰崩是因气候变化冰体崩落引起的，300多名救援队员在搜寻失踪牧民。 本文图片均为@央视新闻 图

　　这一如灾难电影中的场景，是发生在2016年7月17日西藏阿里地区东汝乡的一次罕见冰塌。

　　据新华社的报道以及科学家团队后来的统计，虽然数百人的救援队后来赶到进行了9天的救援，仍有9人死亡，数百头牦牛失踪以及大量的草场被破坏。冰崩形成了面积近10平方公里的冰川塌方体，约相当于1400个足球场大小，体积约0.7亿立方米。

　　紧接着，9月21日，附近的冰川又一次发生罕见的大范围崩塌。

　　全球变暖虽然引发了许多地区的冰川退缩，但阿里曾是个例外，那里的冰川在过去几十年变化缓慢。对于冰川科学家们来说，这两次冰崩被认为彻底颠覆了以前的认识。

　　研究者认为，气候变化极有可能是阿里这两次冰塌的“真凶”，随着当地气温上升以及降水增加，这两次冰崩可能只是今后一系列冰崩灾害的开始。

气候变化极可能是“真凶”
　　在即将发表在《冰河学期刊》（Journal of Glaciology）的一项研究中，来自中国科学院青藏高原研究所、俄亥俄州立大学伯德极地和气候研究中心（Byrd Polar and Climate Research Center ）等机构的研究者们认为，气候变化极有可能是阿里这两次冰塌的“真凶”，随着当地气温上升以及降水增加，这两次冰崩可能只是今后一系列冰崩灾害的开始，对此，现有的科学还没有足够的研究和准备。

　　阿里地区位于西藏的西北部，平均海拔4500米，喜马拉雅山、冈底斯山、喀喇昆仑山横亘其中。研究者统计，阿里地区有5862条冰川，面积约4900平方公里。这些冰川为当地提供了持续稳定的水源，但也包含着灾害风险。

　　过去几十年的监测显示，阿里地区冰川多以温底低、积累量低、变化慢、流速慢为特征，被研究者认为是极为稳定的冰川。而今年崩塌的冰川碎冰带超过了原来的冰川面积，这在历史上都没有记载。对当地气候的监测也表明，随着全球气温上升，在过去的50多年，当地温度也在持续升高。

　　对卫星图片的分析显示，崩塌的冰川变化始于2015年9月的融雪。积水渗透，在冰川下累积，造成底部滑动，而冰川上部却被卡在一个狭小的山谷中，这可能逐渐诱发了灾难。

　　科学家们推测，这种冰川的变化与全球变暖极为相关，但他们仍然需要进行更多的研究。但如果事实如他们猜想的那样，那么阿里的冰崩可能是一种新的冰川灾害，或是一新的冰川退缩方式。它们将再一次敲响全球气候变化的警钟。

　　不过，也有学者持不同看法。

　　中国科学院冰冻圈国家重点实验室康世昌、郭万钦等人认为，阿里的冰崩并非孤立事件，而是如西藏林芝地区南伽巴瓦峰等区域的冰川跃动导致的多次冰崩事件一样，是冰川的周期性运动。

　　郭万钦解释说，目前所知造成冰川跃动的原因主要是冰川内部的周期性不稳定性所导致，外界影响暂时还没有定论。

　　但持有不同观点的研究者同样认为，全球变暖必然导致更多冰川融水进入冰川底床，会在一定程度上改变冰川跃动的发展过程。根据郭万钦所在实验室的数据，中国境内的数千条冰川中，约有1%目前处于跃动期。

预警仍然困难

　　除了冰崩的成因，如何对冰崩灾害进行预警也是研究者们关注的新问题。

　　事实上，科学家们曾成功预警了阿里的第二次冰崩。

　　第一次冰崩发生后，东汝乡当地的牧民们回忆说，事发前几天，他们曾日夜听到冰川发出断裂的声音，但却没有人有所警觉。事发后冰川的异常已经引起多国学者的注意，瑞士苏黎世联邦理工学院、瑞士联邦研究所雪和雪崩组等研究机构的专家在卫星影像中发现，相邻的一个冰川也正在经历类似的变化，冰川上部移位，与主冰川间出现了巨大的裂缝。他们随即通过电子邮件发出警告。

　　在中国，正在进行第一次冰川研究的中国科学院青藏高原研究所研究者田立德等人收到消息后，将这一发现转告了事发地所在的日土县，县政府很快迁出了邻近的牧民，并禁止任何人进入这一区域。

　　如研究者们所预料的那样，第二次冰川发生了，所幸的是，由于采取了预防措施，没有人员伤亡。田立德事后回忆，他当时立即通过邮件分享了这一消息，各国的研究者们都十分欣慰。

　　不过成功的一次预测并不代表预警机制就能很快建立。

　　田立德解释说，大范围内对冰川进行加密连续遥感监测较困难，成本也高。瑞士苏黎世联邦理工学院博士后Silvan Leinss是当时发出警告的专家之一，他也对澎湃新闻（www.thepaper.cn）表示，还有许多客观条件限制冰崩的预警，比如，卫星影响还不能主动发出预警，这需要科学家大量的分析，另外，通过遥感监测，还会遇到云层等气象，它们会遮挡科学家的视野。“人们对于这种气候环境变化的准备还不充分。特别是面对气候环境的突变以及可能出现的由于气候变化导致的不断增加的自然灾害，对科学家与当地政府都提出了新的研究课题。”田立德说。

(责任编辑：窦远行 UN833)
2016-11-24 21:08:50
澎湃新闻