极地的动物将何去何从?

Marika Holland: If you lose sea ice it leads to more warming, which leads to more sea ice loss, which leads to more warming. So there’s this vicious cycle that sets up when you start losing sea ice cover.

玛丽卡．霍兰德：如果海冰消融，全球气候就会变暖，气候变暖反过来也会使海冰消融。所以当海冰开始消融时，地球环境就进入一个恶性循环。

You’re listening to Marika Holland, a scientist at the National Center for Atmospheric Research. She and other scientists are researching whether there might be a ‘tipping point’ for Arctic sea ice – a point at which sea ice will disappear and never recover, even if the climate cools. So far though she hasn’t found evidence for that tipping point.

今天节目组采访了美国国家大气研究中心科学家玛丽卡．霍兰德。她与同事致力于研究对于北冰洋上的海冰是否存在一个不可逆转的“消融点”，一旦达到该点即使气候转凉海冰也无法恢复原来的覆盖量。目前为止，她还没有找到该点存在的证据。

Marika Holland: So there’s been a lot of speculation from some scientists that we could have already passed a tipping point, or be close to a tipping point. And I’m trying to investigate this using climate models.

玛丽卡．霍兰德：一些科学家就此进行了种种推测，他们认为实际上海冰的消融已经达到了不可逆转的程度，或者与之非常接近。而我所做的就是采用气候模型对此进行调查。

Holland’s models look at the physical response of sea ice to different levels of greenhouse gas emissions.

霍兰德的模型能够反映出不同的温室气体排放量对海冰覆盖面及厚度造成的影响。

Marika Holland: We’re still on this path of decreasing sea ice cover, but if things were stabilized in terms of greenhouse gas concentrations, we might be able to stabilize the sea ice cover as well.

玛丽卡．霍兰德：目前海冰仍在日益消融，但假如温室气体排放量能够稳定下来，也许海冰的覆盖面也将维持稳定。

In other words, Holland’s research suggests that summertime sea ice – which is predicted to disappear by mid-century – could possibly recover to its previous extent and thickness.

换句话说，霍兰德的研究表明，原本预计本世纪中期完全消失的夏季海冰有可能恢复原来的覆盖面和厚度。

Marika Holland: I think it’s a strong suggestion that reducing emissions of greenhouse gases, fossil fuel burning can actually have an impact on Arctic sea ice cover, that not all hope is lost.

玛丽卡．霍兰德：我觉得这充分说明了，减少温室气体排放量和化石燃料燃烧确能阻止北冰洋海冰消融，我们仍然存有一线希望。