How to track a tornado - Karen Kosiba

如何追踪龙卷风—— Karen Kosiba

翻译人员: Cissy Yun 校对人员: Jenny Yang

So, I think all good tornado talks need to start

我认为所有关于龙卷风的精彩演讲

都得从一张令人叹服的龙卷风照片开始

with an awesome tornado shot.

And this is not that awesome tornado shot.

好吧，那不是一张很棒的龙卷风照片

That was the first tornado I ever saw, it was really cool, really scary,

其实，这是我见到的第一个龙卷风

它十分炫酷，但也十分恐怖

and I'm showing it to you guys

我之所以想把它展示给你们

是因为它让我第一次走近龙卷风

because that's why I got into the field in the first place.

所以，这虽然是一张很烂的照片

So even though it's a bad photograph,

it was really cool to be out there the first time.

置身于龙卷风旁还是十分的酷的

如今，我已经在拍摄一些专业的龙卷风视频了

But now I'm taking real tornado footage.

Fast forward a few years.

快进到几年前

This is a few years ago, during a field project called VORTEX2,

当年

在一个实地项目叫做VORTEX2(漩涡2)中

where myself and a bunch of other scientists were out there,

我与一 群科学家正处在龙卷风附近

用不同的仪器

surrounding tornadoes with different types of instrumentation

and trying to figure out how tornadoes form.

尝试找出龙卷风形成的原理

我们想找到 一个问题的答案

It's a big question we're trying to answer.

这听起来是一个十分基础的问题

It sounds like a very basic one,

but it's something we're still trying to figure out.

然而，如今我们依旧在寻求其答案

另一个我们想知道的问题是

We're also still trying to figure out what the winds are like near the surface.

靠近龙卷风表层的风是怎样吹的

We know what the winds are like above building level,

我们已经知道的是楼层高度以上的风是如何运作的

但依旧困扰我们的是龙卷风表层的风向运作

but we really don't know what they're like at the surface

以及它是如何与楼层高度之上的龙卷风 联系起来的

and how that relates to what we're seeing above building level.

大多数龙卷分都是由“超级单体雷暴”组成的

Most tornadoes form from what we call supercell thunderstorms.

这种“超级单体雷暴”

Supercell thunderstorms are what you commonly think of

就是你们所熟知的 引起龙卷风的风暴

as tornado-raising storms.

They're big, rotating thunderstorms

它们是一种十分巨大的，旋转型风暴

that happen a lot of times in the midsection of the United States.

多发生于美国中部地区

But the problem is that even though they're rotating up above,

但问题是

即使这种风暴的上部一直在旋转

it doesn't mean they're rotating at the surface.

并不代表它的表层风向也在旋转

And when we look at these storms

当我们观察这种风暴

观赏这些图片

and at these pictures and at the data we have,

并且研究这些数据时

they all kind of look the same.

它们是十分相像的

这种龙卷风存在很多不确定因素

And it's really problematic

if we're trying to make tornado forecasts or warnings,

当我们想要发出龙卷风预警

because we only want to warn or forecast about the storms

我们只是想要对这些风暴发出警告

或是发出将会造成

that are going to actually make a tornado.

龙卷风的风暴预警

One of the big, critical distinguishing features, we think, between these storms,

一个十分重要的

存在于这些风暴之间的区别

有关一种名为后侧下环流的风

is something about the rear-flank downdraft.

So these big rotating thunderstorms have this downdraft

这些旋转型风暴的

背部被这种倒灌风包裹着

that wraps around the rear edge of it,

hence the "rear-flank" downdraft.

所以被称为后侧下环流

But we think how warm that is, how buoyant that air is,

但当我们想到它的温度

它的浮力

and then also how strong the updraft it's wrapping into,

以及它的上环流风的力量

将这些总结起

也许就会形成

makes a big difference on whether or not it's going to make a tornado.

一个龙卷风

There's a lot more that goes into it --

当然，还有其他很多的因素

我一会儿告诉你们

I'll tell you about that in a second.

当你真的遇见一个龙卷风时

Once you actually get a tornado, again, the problem that we have

对于我们问题就是

is getting measurements near the surface.

如何去测量表层的一些数据

It's really hard to get measurements near the surface --

测量龙卷风表层数据是十分困难的

多数是因为人们不愿意靠近龙卷风

most people don't want to drive into tornadoes.

There are a few exceptions; you might have seen them on TV shows.

当然，也会有一些例外

也许你们在电视上也看到过一些这样的例子

But most people don't want to do that.

但大多数人不会这样做

Even getting instrumentation in the path of the tornado is pretty tricky, too.

即使是使用仪器研究龙卷风也会十分困难

Because, again, you don't want to be that close to a tornado

当然，你不会想离龙卷风太近

因为龙卷风附近的风也是十分强劲的

because sometimes the winds around the tornado are strong as well.

所以获取信息的关键的地点 对我们来说十分重要

So getting information, that critical location,

is key for us because, again, we don't know

因为，我们不知道

if the winds that we're seeing above ground level,

在地平线以上的风和

way above building level,

在楼层高度以上的风

actually map to the surface,

是否可以表层的风是有所比对

if they're stronger, weaker, or about the same

它们也许比其更强烈，也可能相对微弱

它们也可能和楼层高度以上的风 有相似的强度

as what we're seeing above buildings.

The way we get at answering a lot of these questions --

我们拥有寻找这些问题的答案的方法

我是一个观察师，所以我喜欢做实地考察

and I'm an observationalist; I love to get out in the field,

我也喜欢收集有关龙卷风的数据

and collect data on tornadoes --

我们编制了许多观测实例

we compile a lot of observations.

我与一组操控"车载雷达"的科学家一起工作

I work with this group who operates mobile radars,

and they're exactly what they say -- basically, a radar

正如其名

“车载雷达”基本上就是 安装在一辆蓝色卡车上的雷达

on the back of a big blue truck,

我们开着它靠近龙卷风

and we drive up really close to tornadoes to map out the winds.

勘察龙卷风以及规划我们的预测

We map out the precipitation.

We map out all these different things that are going on

我们将所有的的细节都记录下来

为的是更了解这些风暴的形成步骤

in order to better understand the processes in these storms.

And that bottom there, that's what a tornado looks like

看到左下方的这个图片

这就是龙卷风

when you're looking at it with a mobile radar, and really close.

在“车载雷达”中显示出的样子

“车载雷达”需靠龙卷风十分近

Also, what we do is a lot of modeling,

我们还会建立许多模型

so we do a lot of computer models and simulations,

我们会建立许多电脑模型和拟态

because the atmosphere is governed by the laws of physics.

因为大气层是由物理定律控制的

所以我们可以建立关于物理定律的模型

So we can model the laws of physics

and see where the tornado might go,

然后预测龙卷风的走向

where the storm might go,

风暴的走向

how strong the winds are near the surface

以及表层风的强度

and not actually have to go out in the field.

这样，我们不用去到实地 就可以完成这些考察

但是，我们希望建模和考察能够同时进行

But of course, we want to have both observations and modeling

这样会更科学

to move forward with the science.

这是一段视频 我前面也给你们看过

So, I showed you that video earlier that went real quick, too.

This is what it looks like, looking at it with a radar.

这就是通过雷达观测龙卷风时 其所呈现的形态

就是你们现在看到的

So you saw it visually,

but this is what I get really excited about when I see now in the field,

当时我在在实地考察中看到这个时

我感到很兴奋

可以以这种形态观察龙卷风

stuff that looks like this.

这是很振奋人心的一件事

The really exciting thing about looking at stuff like this

这个风暴

is that we caught this storm from when it didn't make a tornado

当我们捕捉到不同时期的龙卷风 有还未成形的

也有逐渐形成的龙卷风

to when it made a tornado and intensified

我们看着它渐渐地增强

然后逐渐地消散

and when it dissipated.

This is the one of the rare data sets that we have out there

所以，这是我们拥有的一个

十分少见的数据

它可以让我们研究龙卷风的整个形成周期

that were able to study the entire life cycle of a tornado.

I talked about how we think that rear-flank downdraft is important

我会讲到一种后飞倒灌风

它是一种对我们来说十分重要的风

because it tilts, there's a lot of spin in the atmosphere,

因为它会倾斜，并在大气层中不断旋转

but the problem with all this spin in the atmosphere

但问题是所以在大气层中的旋转

is it needs to be oriented vertically,

都需要是以垂直为中心点

because that's what tornadoes are doing,

这也是龙卷风所做的事

and it needs to orientated vertically near the ground.

它需要靠近地面作垂直旋转

So we think this rear-flank downdraft just pulses.

所以说，当我们想到后飞倒灌风时 我们会将它看作震动

我们觉得很重要的

And these pulses in this rear-flank downdraft, we think,

这些震动

are very important for converging that rotation,

可以收缩这些旋转

but also getting that rotation into the right place.

也会指引龙卷风向正确的方向旋转

Other things we've learned

我们学到的另一件事是

is that we have gotten a bunch of fortuitous measurements

我们得到了很多关于龙卷风附近

龙卷风表层

in the path of the tornadoes and very near the surface.

的一些偶然的数据

And we found out

我们发现靠近表层的风

that the winds near the surface are actually pretty comparable

是比得上

30，40米高度以上的风

to what we're seeing 30, 40 meters above ground level.

So there's not a big reduction in what we're seeing above the surface

所以，表层的风并不会比

楼房高度的风弱

to what we're seeing at house level.

And that was a pretty surprising finding for us,

这是一个比较惊奇的发现

因为，我们以前总是认定

because we kind of assumed that the winds decrease

接近表层的风力会相对变弱许多

pretty substantially near the surface.

我将会用这张图来结束我的演讲

I'm going to end with this real quick.

And this is not my last tornado I ever saw,

这并非是我见过的最后一个龙卷风

但我十分喜欢这个图片

but I really like this image,

because this was taken with one of those mobile radars I was talking about.

因为它是由我先前提到的“车载雷达” 所记录下来的

这是一个龙卷风，并非飓风

This is a tornado, not a hurricane,

这是当你十分靠近它时

and this is what it looks like when you're really close to it.

所呈现的样子

我觉得很惊奇的地方是

And I find this amazing,

我们可以运用技术

that we can actually take technology this close to these types of storms

来接近这种风暴

and see these inner workings.

观察它们的内部

如果你经常看龙卷风的图片

And for those of you who look at tornado images often,

you can see there's a lot going on -- there's rain spiraling,

你可以发现它包含许多内容

雨水急骤下落， 你甚至可以看到碎片云

and you can actually see the debris cloud associated with this tornado.

和龙卷风共存

我十分期望看到未来和新的技术

I look forward to the future and future technologies

and being able to learn a lot more about these storms,

我们可以运用它们来更好的研究这些风暴

as the world advances,

随着世界的进步

as you guys contribute to the science

当你们投身于科学之中

and we're able to really learn more about how tornadoes form.

我们将会获取更多关于龙卷风形成的知识

Thank you.

谢谢！

(Applause)