Global S&T Development Trend Analysis Platform of Resources and Environment
Double climate disaster may have ended ancient Harappan civilisation | |
admin | |
2020-11-26 | |
发布年 | 2020 |
语种 | 英语 |
国家 | 国际 |
领域 | 气候变化 ; 资源环境 |
正文(英文) | ![]() Suzuki Kaku/Alamy Even for a civilisation as advanced as the Harappan, a second drought was perhaps one too many. A two-pronged climate catastrophe may be what drove the ancient society to disperse and eventually disappear. The Harappan arose in the Indus valley between north-east Afghanistan and north-west India around 5200 years ago, peaking around 2600 BC. Much about them is unknown, as their written script is still undeciphered. Yet archaeological remains tell the story of a sophisticated people, skilled in metallurgy, trade and urban planning, and particularly adept at controlling water. Their huge cities, complete with intricate sewer systems, reservoirs and public baths, long predated the Roman Empire. But by 1900 BC, their society seemed to be in decline, and by 1300 BC, the Harappan civilisation had collapsed.
AdvertisementSeveral ideas have been put forward to explain the downfall, including invasion and climate change. One recent hypothesis pins it to a major drought in the northern hemisphere around 4200 years ago. This event was recently declared as the start of the Meghalayan period of the Holocene geological epoch. It is thought to have disrupted climate systems around the world, including the summer monsoon rainfall the Harappan depended on. Nick Scroxton at University College Dublin, Ireland, and his colleagues are now challenging this idea after analysing 10 recently reported palaeoclimate records. These come mostly from stalagmites from cave sites around the Indian Ocean, including one from Madagascar and a sediment core from the Arabian Sea. Together, they provide a region-specific view of the evolving climate during the rise and fall of the Harappan. Scroxton and his team found some evidence of a relatively sudden drought starting around 4260 years ago. Rather than affecting summer monsoons though, the analysis suggests the Harappan faced a sharp decrease in winter rain. “The civilisation suffered, that’s for sure,” says Scroxton. But that wasn’t the end of the Harappan. Archaeological findings suggest they abandoned their grand cities in the Indus valley and continued living in the south around present-day Indian state of Gujarat. Botanical evidence suggests the Harappan also switched from winter crops like barley and wheat to those like millet that favour summer rain conditions. “Their politics might change, the crops might change, the location of their cities changes, but they adapt,” says Scroxton. Some 300 years later, however, just as the winter rains were starting to recover, a tropical drought kicked off. This was a gradual reduction in the summer monsoon rains over several centuries. Scroxton and his colleagues say this second drought transformed the Harappan into a rural, agrarian society that eventually faded away. The conclusions are quite plausible, says Peter Clift at Louisiana State University and fit with other records from Rajasthan in western India and the Indus river delta. He is a little concerned about the study being based largely on stalagmites, however, pointing to some in China that were recently shown to be unreliable. Julien Emile-Geay at the University of Southern California says the study offers a well-constructed argument and adds a more-refined view of the changing climate at that time. Journal reference: Climate of the Past, DOI: 10.5194/cp-2020-138 More on these topics: |
URL | 查看原文 |
来源平台 | NewScientist |
文献类型 | 新闻 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/305333 |
专题 | 资源环境科学 气候变化 |
推荐引用方式 GB/T 7714 | admin. Double climate disaster may have ended ancient Harappan civilisation. 2020. |
条目包含的文件 | 条目无相关文件。 |
个性服务 |
推荐该条目 |
保存到收藏夹 |
查看访问统计 |
导出为Endnote文件 |
谷歌学术 |
谷歌学术中相似的文章 |
[admin]的文章 |
百度学术 |
百度学术中相似的文章 |
[admin]的文章 |
必应学术 |
必应学术中相似的文章 |
[admin]的文章 |
相关权益政策 |
暂无数据 |
收藏/分享 |
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。
修改评论