冰盖的改革如果它们消失了吗?- 江南体育网页版- - - - -地球科学堆江南电子竞技平台栈交换 最近30从www.hoelymoley.com 2023 - 04 - 05 - t18:39:16z //www.hoelymoley.com/feeds/question/10503 https://creativecommons.org/licenses/by-sa/4.0/rdf //www.hoelymoley.com/q/10503 5 冰盖的改革如果它们消失了吗? joshisanonymous //www.hoelymoley.com/users/8281 2017 - 06 - 01 - t16:44:12z 2019 - 03 - 13 - t05:10:48z < p >原谅我的无知。我印象中有各种类型的在两极的冰,但我不知道区别或每种类型的重要性,因此,在任何实际上是融化在这些地区由于气候变化,这是可能的,它可以回来如果温室气体排放被淘汰或类似的东西?基本上,我假设冰帽是必要的为了维护地球可居住的人类,所以有某种阈值的融化基本上算是只能进不能退的地步还是总是看到冰帽的可能性回归安全水平? < / p > //www.hoelymoley.com/questions/10503/-/10504 # 10504 2 回答约翰冰盖的改革如果它们消失了吗? 约翰 //www.hoelymoley.com/users/7080 2017 - 06 - 01 - t21:07:56z 2017 - 06 - 02 - t03:32:18z < p >是的他们可以改革即使完全融化,他们这样做在地质的过去,你只需要足够地球降温。< / p > < p >你只需要两件事情对于地球上的冰帽,大陆在正确的位置(在两极附近)和足够低的温度。当前南极冰盖在约3400万年前同时形成的。< / p > //www.hoelymoley.com/questions/10503/-/10507 # 10507 8 回答由jeffronicus冰盖的改革如果它们消失了吗? jeffronicus //www.hoelymoley.com/users/7314 2017 - 06 - 01 - t23:34:11z 2017 - 06 - 05 - t03:57:35z < p >是的,极地冰川融化——值得注意的是,如果不完全,大量对人类文明的影响。它可以稳定和恢复,但问题是什么速度相对于人类文明。< / p >

There are generally three types of polar ice:

Sea ice is usually 1-2 meters thick; shelf ice is 100-200 meters thick; sheet ice is one to several kilometers thick.

The poles differ significantly. It's often pointed out that the Arctic is an ocean surrounded by land and the Antarctic is land surrounded by ocean. The North Pole is occupied by sea ice, about half of which melts every summer and reforms every winter.

At the other extreme are the ice "caps," more or less the ice sheets in Greenland and Antarctica that extrude ice in the form of glaciers and ice shelves that continuously flow into the ocean, breaking apart and melting.

To take just Greenland: Greenland has had some degree of glaciation for ~38 million years, but lost much or almost all of its ice during a warming period about 400,000 years ago, suggesting that the current ice sheet was created in that time.

The evidence suggests nearly total ice-sheet loss may result from warming of more than a few degrees above mean 20th century values, but this threshold is poorly defined (perhaps as little as 2 °C or more than 7 °C).]5

(That melt ice is equivalent to about 7.3 meters of global sea level rise.)

So, yes, the ice sheets can melt away; how quickly they can melt will be driven by the amount and pace of CO2 emissions; the extent of that melting will be affected by the duration of that CO2 in the atmosphere and the impact of potential feedbacks.

The formation of an ice sheet -- glaciation -- can occur relatively rapidly in the correct conditions, according to this IPCC Assessment report on paleoclimate, which notes glaciation occurring in some regions of the world within a period of centuries.

In the short term, the most obvious impact we're seeing from global warming is the steady decline in the extent of Arctic Sea ice, at about 2.6 per decade since the satellite record began in 1979. Research suggests that this ice can come back, eventually:

The central finding of this study is that sea ice loss is fully reversible in a state-of-the-art GCM over a range of CO2 concentrations from the 1990s level to nine times higher. We find no evidence for threshold behavior in the summer or winter ice cover in either hemisphere. Thus if tipping points exist for future sea ice retreat in nature, it is for subtle reasons, i.e., through processes that are absent or inadequately represented in this model.

However, this team of researchers suggested an extensive project to prevent a worst-case scenario:

This loss of sea ice represents one of the most severe positive feedbacks in the climate system, as sunlight that would otherwise be reflected by sea ice is absorbed by open ocean. It is unlikely that CO2 levels and mean temperatures can be decreased in time to prevent this loss, so restoring sea ice artificially is an imperative. Here we investigate a means for enhancing Arctic sea ice production by using wind power during the Arctic winter to pump water to the surface, where it will freeze more rapidly.

//www.hoelymoley.com/questions/10503/-/10512 # 10512 2 答案由安德鲁·乔恩·多兹冰盖改革如果它们消失了吗? 安德鲁·乔恩·多兹 //www.hoelymoley.com/users/8217 2017 - 06 - 02 - t08:11:12z 2017 - 06 - 02 - t08:11:12z < p >冰盖不是必不可少的适宜居住的行星,在地质历史,他们通常缺席。融化他们会麻烦许多人类,不过,有一个很好的计算器< a href = " http://www.floodmap.net/ " rel = " nofollow noreferrer " >在< / > < / p > < p > Jeffronicus回答最多的,但作为一个直接的回答问题的一部分,在< a href = " http://www.nature.com/nclimate/journal/v2/n6/full/nclimate1449.html " rel = " nofollow noreferrer " >格陵兰冰盖< / >可能是亚稳态,在今天如果你神奇地删除它,它不会再生,除非气候明显冷却器。南极西部冰盖可能已经动摇——这是接地低于海平面,一旦它开始又是不可阻挡的,但它可以长回来。< / p >
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