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所在平台: Coursera |
课程主页: https://www.coursera.org/learn/arctic-present-past-future
课程评论：没有评论
课程名称：变化中的北极：现在、过去与未来 概述：本课程深入探讨北极环境中正在发生的显著变化，包括北极海冰覆盖的减少、陆地冰体的缩小、永冻土的融化以及对北极生态系统的连锁影响。在回顾过去的北极气候后，课程将关注北极气候和环境的可能未来。 课程大纲： 1. **改变的可见指标** - 本模块介绍北极气候变化的一些显著可见指标，如海冰覆盖的减少和北极的强烈变暖现象（称为“北极放大”）。还将探讨永冻土的变暖与融化，以及与海冰损失、海洋变暖和永冻土变暖相关的沿海侵蚀问题。 2. **陆地冰体的缩小** - 北极包含格林兰冰盖，这是地球上仅有的两个冰盖之一（另一个是南极冰盖）。大多数冰体正在失去质量，导致海平面上升。本模块将讨论格林兰冰盖的质量平衡复杂过程及1980年代被研究的小冰盖消失的悲剧。 3. **变暖北极的连锁影响** - 本部分将探讨北极变化对区域外的影响，包括北极放大如何可能影响中纬度的天气模式。北极正经历极端天气事件，且草木稀疏的苔原正被灌木取代，海冰的减少对从浮游植物到北极熊等顶级捕食者的海洋食物链产生了连锁影响。 4. **学习过去** - 理解北极近期气候变化和未来走向的关键在于研究过去气候（古气候学）。本模块探讨古气候学的科学、不同类型的古气候数据以及过去气候变化的原因，尤其专注于过去百万年及现代的气候变化，铺垫未来的讨论。 5. **未来的北极** - 虽然气候模型是预测未来北极变化的重要工具，但它们也存在偏差和不确定性。本模块将探讨预计的气温、降水量和海冰变化。同时，课程强调这些变化的 magnitude 将在很大程度上取决于人类行为，尤其未来化石燃料消费的速度。最后，我们将查看永冻土碳反馈及其对全球变暖的潜在影响。
Part: 1
Title:Visible Indicators of Change
Description:The Arctic is home to some of our planet's most visible indicators of climate change and we'll learn all about them in this module. Notable among these are the shrinking Arctic sea ice cover and the stronger warming of the Arctic compared to the rest of the globe, a phenomenon known as "Arctic Amplification". We'll then look at how the Arctic permafrost - perennially frozen ground - is warming and thawing. Finally, attention will turn to a direct threat to Arctic residents - coastal erosion and how it is tied to sea ice loss, ocean warming and warming permafrost.
Part: 2
Title:Shrinking Land Ice
Description:The Arctic is home to the Greenland ice sheet, one of the planet's two ice sheets (the other is the Antarctic ice sheet) as well as many ice caps and glaciers. With few exception, these ice bodies are losing mass and contributing to sea level rise. Here we'll learn all about the Arctic's shrinking land ice, including the complexity of processes affecting the mass balance of the Greenland ice sheet, and the sad story of the disappearance of the two small ice caps that your instructor studied back in the early 1980s.
Part: 3
Title:Cascading Impacts of a Warming Arctic
Description:Here, we'll discover how changes in the Arctic are having cascading effects not just within the Arctic, but beyond the region. There is is evidence, albeit still controversial, that the strong warming of the Arctic, known as Arctic amplification, can influence weather patterns in middle latitudes. We'll see that the Arctic itself is experiencing extreme weather events. We'll also explore how treeless, windswept tundra is being taken over by shrubs, and how the loss of sea ice is is having impacts cascading through the marine food chain from phytoplankton to top predators like the polar bear.
Part: 4
Title:Learning from the Past
Description:A key part of understanding recent climate change in the Arctic, as well as where the Arctic may be headed, is to understand climates of the past - the realm of paleoclimatology. Here, we'll learn about the science of paleoclimatology, different types of paleoclimate data and some of the causes of past climate changes. The Arctic turns out to be a rich course of paleoclimate data. Then we'll focus on climates from the past million years up to the modern period, noting the tremendous changes that have occurred in the Arctic and elsewhere, setting the stage for a peek into the future.
Part: 5
Title:The Future Arctic
Description:In this module, we'll first learn that while climate models are a key tools for making projections about the future Arctic, they also have biases and uncertainties. We'll then take a look at projected changes in temperature, precipitation and sea ice. We'll see that the Arctic is expected to continue to warm more strongly than the rest of the planet, that Arctic precipitation is likely to increase and that the sea ice cover will continue to shrink. However, it will also become clear that the magnitude of these changes will very much depend on human behavior - specifically, future rates of fossil fuel burning. Finally, we'll look at the permafrost carbon feedback, and its potential to lead to further warming of the planet.
This course takes a detailed look at the remarkable changes unfolding in the Arctic environment, including the shrinking Arctic sea ice cover, shrinking land ice, thawing permafrost and cascading impacts on Arctic ecosystems. After a review of Arctic climates of the past, attention turns to the possible future of the Arctic’s climate and environment.
