50年后的天气情况是怎么样的?

Today, a climate scientist in the U.K. responds to critics of computer modeling. Critics claim that if forecasts of weather just days away are often wrong, how can scientists claim to know what climate will be like 50 years out?

今天，来自英国的气候学家回应了那些质疑计算机建模的评论家。那些评论家声称科学家们连近几天的天气都预报不准，怎么能夸下海口说知道50年后的天气情况呢。

Vicky Pope: We can look at the range of possible outcomes. We’re not saying that there is only one possible future if you do particular emissions. We say there’s a range of possible futures, and that range is representative of the uncertainty in the science.

维琦．波普：我们能看到一串可能的结果。我们并没说未来天气的预测结果只有一种可能性。我们会得到一个范围区间，范围内的波动代表了科学中的不确定因素。

That’s Vicky Pope talking about the range of possible risks of climate change. She heads climate change science for the Hadley Centre of the Met Office, the United Kingdom’s national weather service. The Hadley Centre produces some of the world’s most-used climate models. They crunch numbers that simulate the processes that drive Earth’s climate, like incoming sunlight and the circulation and composition of the ocean and atmosphere.

维琦．波普正在谈论气候变化风险评估结果的波动范围。她是英国国家气象局哈德利中心研究气候科学的领头人。哈德利中心研发出了世界最常用的气候模型。他们综合日射日光、海洋和大气的成分及流通的有关数据，模拟影响地球气候变化的过程。

Vicky Pope: The models are based on the laws of physics. So they’re solving the equations represent those laws. We also run the model every day as a weather forecast. We test it that way. And we compare models’ past climate with the observed climate, not just in terms of temperature, but in terms of the physical processes that are important for climate change – like cloud feedbacks, for example.

维琦．波普：这些模型都是以物理定律为基础建立上。它们实际在解这些定律的方程。我们每天都会用该模型预测天气。这样就可以测试模型是否准确。我们把模型提前预测好的天气和实际观测的天气的情况对比，对比的参数不仅限于温度，还有那些对气候变化至关重要的物理过程，比如云反馈作用。

Dr. Pope said the computer models aren’t perfect but do the best humanity has for predicting future climate.

波普博士说计算机模型不是完美的，但为人类预测天气做出最大的努力。