英语 英语 日语 日语 韩语 韩语 法语 法语 德语 德语 西班牙语 西班牙语 意大利语 意大利语 阿拉伯语 阿拉伯语 葡萄牙语 葡萄牙语 越南语 越南语 俄语 俄语 芬兰语 芬兰语 泰语 泰语 泰语 丹麦语 泰语 对外汉语

VOA慢速英语2013 不断上升的气温可能会意味着更多的森林大火

时间:2013-09-13 14:20来源:互联网 提供网友:nan   字体: [ ]
    (单词翻译:双击或拖选)

 

AS IT IS 2013-09-11 Rising Temperatures Could Mean More Wildfires 不断上升的气温可能会意味着更多的森林大火

From VOA Learning English, welcome to As It Is! I’m Mario Ritter.

On our show today, we hear from two weather experts. We hear from one scientist who gets close to tornadoes2 to learn more about the destructive storms.

“I invented the Doppler on Wheels back in the 1990s because I was frustrated3 that we couldn’t see enough detail inside tornados4 and hurricanes.

But first we hear how climate change may affect wildfires. One, soon-to-be-released report says huge fires may become more common in the future.

Could Warming Temperatures Mean Fiercer Wildfires?

Powerful, intense fires have been burning out of control in parts of the western United States.

In a new report, scientists are predicting more and bigger wildfires over bigger areas and for longer periods in the western United States. But, some people say rising temperatures on our planet could be partly to blame for the severity of wildfires.

Steve Ember has more from a report by VOA’s Rosanne Skirble.

Fires in the United States have gotten worse since the 1970s. Scientists at Harvard University in Massachusetts looked at past weather conditions and wildfires to find out why. Atmospheric5 chemist Loretta Mickley is a researcher and helped to organize a new study. She says high temperatures and rainfall in other years can create the conditions for large fires.

“In some regions, like the Rocky Mountains, really, temperature is the driving force, but elsewhere variables like relative humidity can play a role. If one year is particularly moist, for example, in the Great Basin, Nevada, Utah area, then that will foster a lot of vegetation growth and then the following year all that vegetation can feed wildfires and their spread.”  

She and other researchers examined 15 climate models from the Intergovernmental Panel on Climate Change. The panel is the leading international organization that measures climate change. The models predicted average temperature increases of between two and 2.5 degrees Celsius6 by 2050.

Loretta Mickley says her team’s research suggests that rising temperatures are linked to fire activity.  

“So we found, as in the past, temperature is really driving the changes that we predict for the future.” 

She says the measurements suggest that the chance of large wildfires will increase by two or three times. Currently, the fire season, the period when most fires take place, is a little over four months. Loretta Mickley says that, by 2050, it will be three weeks longer. She says in the Rocky Mountains, the area burned by fires could increase by as much as four times.

Fires do more than burn forests. Air quality is also harmed by the huge amounts of smoke produced. In the past 20 years, air quality in many parts of the United States has improved greatly because of federal laws and better technologies. But, Loretta Mickley says, air pollution is an unexpected result of longer lasting7, widespread wildfires.

“But these increases in wildfires could totally disrupt our efforts to clean the air. Last weekend there was an area the size of some states in the eastern U.S. blanketed with unhealthy air over California and Nevada. And, we call this increase in smoke an important climate penalty on air quality.”

That penalty would be air that is two times as smoky as it is today. Ms. Mickley says these estimates suggest the need for better forest management. And, she adds, they send a warning sign to lawmakers and the public to reduce fossil fuel emissions8 that many scientists believe are warming the planet.

A report on the study will appear next month in the journal Atmospheric Environment. I’m Steve Ember.

A Scientist Who Gets Very, Very Close to a Tornado1

Weather experts are able to predict bad weather better than ever before thanks to satellites, high-altitude balloons and radar9 stations. But for many years these experts have incorrectly predicted tornado formation giving false warnings about 75 percent of the time.

So, scientists are working to improve their tornado predictions.

--------------June Simms reports.

Doppler is a type of radar that identifies weather conditions based on the flow and speed of objects through the air.

Scientist Joshua Wurman was the first to put Doppler radar equipment on a vehicle and drive it into the path of a tornado.

“I invented the Doppler on Wheels back in the 1990s because I was frustrated that we couldn’t see enough detail inside tornados and hurricanes. We had blurry10 images of all these things and in order to really understand the physics -- the math of what is going on inside a tornado, how exactly are they forming, how strong are the winds right at the surface are -- we need to get up very, very, close.”

Mr. Wurman heads the Center for Severe Weather Research in Boulder11, a city in the western state of Colorado. He has put his Doppler radar equipment on large trucks. The high-powered antennas12 continuously turn in circles. They send out radio waves that hit objects in the air -- like raindrops, and birds. Mr. Wurman and his colleagues sit inside the truck and study the computer images formed by the signals that return.

“I’m seeing it through the computers and through the radar screens, which are making three-dimensional images of the wind and the debris13 and the rain and hail, flowing around the storm.”

Using information from satellites, stationary14 radar networks, and computer models, the team finds a storm that could become a tornado and drives the truck right into that area. Doppler on Wheels has been close to over 200 tornados so far.

“When we get up close to a storm while it’s in the process of making a tornado we can look at the evolution of the winds near the surface, how that relates to the winds aloft, how the precipitation, the rain and the hail influences whether the air is going up or down, whether it’s cold or warm and how that is causing or not causing a tornado to form.”

The examination combines the Doppler-created images, 3-D maps and information gathered by measuring instruments on the ground in the path of a storm.

Information gathered by the instruments could help builders design stronger homes in areas where such dangerous storms are common.

Scientists are learning more about which storms develop into tornados by studying them from start to end. Mr. Wurman says that radar information has taught them that a “wind surge” could be what causes a storm to turn into a tornado. 

I’m June Simms.

Finally, September 11th is Patriot15 Day in the United States. It is the day when Americans remember the over 3,000 people killed and the thousands injured during the September 11th, 2001 terrorist attacks against the United States.


点击收听单词发音收听单词发音  

1 tornado inowl     
n.飓风,龙卷风
参考例句:
  • A tornado whirled into the town last week.龙卷风上周袭击了这座城市。
  • The approaching tornado struck awe in our hearts.正在逼近的龙卷风使我们惊恐万分。
2 tornadoes d428421c5237427db20a5bcb22937389     
n.龙卷风,旋风( tornado的名词复数 )
参考例句:
  • Tornadoes, severe earthquakes, and plagues create wide spread havoc. 龙卷风、大地震和瘟疫成普遍的毁坏。 来自互联网
  • Meteorologists are at odds over the working of tornadoes. 气象学者对龙卷风的运动方式看法不一。 来自互联网
3 frustrated ksWz5t     
adj.挫败的,失意的,泄气的v.使不成功( frustrate的过去式和过去分词 );挫败;使受挫折;令人沮丧
参考例句:
  • It's very easy to get frustrated in this job. 这个工作很容易令人懊恼。
  • The bad weather frustrated all our hopes of going out. 恶劣的天气破坏了我们出行的愿望。 来自《简明英汉词典》
4 tornados 64f19dd0af7a26fe4bcdede94053f93c     
n.龙卷风,旋风( tornado的名词复数 )
参考例句:
  • And the national weather service reports several tornados touch down. 国家气象中心报告预测龙卷风将来袭。 来自互联网
  • They had stock footage of lightning, tornados, and hurricanes. 他们存有关于闪电、龙卷风和飓风的电影胶片。 来自互联网
5 atmospheric 6eayR     
adj.大气的,空气的;大气层的;大气所引起的
参考例句:
  • Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
  • Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。
6 Celsius AXRzl     
adj.摄氏温度计的,摄氏的
参考例句:
  • The temperature tonight will fall to seven degrees Celsius.今晚气温将下降到七摄氏度。
  • The maximum temperature in July may be 36 degrees Celsius.七月份最高温度可能达到36摄氏度。
7 lasting IpCz02     
adj.永久的,永恒的;vbl.持续,维持
参考例句:
  • The lasting war debased the value of the dollar.持久的战争使美元贬值。
  • We hope for a lasting settlement of all these troubles.我们希望这些纠纷能获得永久的解决。
8 emissions 1a87f8769eb755734e056efecb5e2da9     
排放物( emission的名词复数 ); 散发物(尤指气体)
参考例句:
  • Most scientists accept that climate change is linked to carbon emissions. 大多数科学家都相信气候变化与排放的含碳气体有关。
  • Dangerous emissions radiate from plutonium. 危险的辐射物从钚放散出来。
9 radar kTUxx     
n.雷达,无线电探测器
参考例句:
  • They are following the flight of an aircraft by radar.他们正在用雷达追踪一架飞机的飞行。
  • Enemy ships were detected on the radar.敌舰的影像已显现在雷达上。
10 blurry blurry     
adj.模糊的;污脏的,污斑的
参考例句:
  • My blurry vision makes it hard to drive. 我的视力有点模糊,使得开起车来相当吃力。 来自《简明英汉词典》
  • The lines are pretty blurry at this point. 界线在这个时候是很模糊的。 来自《简明英汉词典》
11 boulder BNbzS     
n.巨砾;卵石,圆石
参考例句:
  • We all heaved together and removed the boulder.大家一齐用劲,把大石头搬开了。
  • He stepped clear of the boulder.他从大石头后面走了出来。
12 antennas 69d2181fbb4566604480c825f4e01d29     
[生] 触角,触须(antenna的复数形式)
参考例句:
  • Marconi tied several antennas to kites. 马可尼在风筝上系了几根天线。 来自超越目标英语 第3册
  • Radio astronomy today is armed with the largest antennas in the world. 射电天文学拥有世界上最大的天线。
13 debris debris     
n.瓦砾堆,废墟,碎片
参考例句:
  • After the bombing there was a lot of debris everywhere.轰炸之后到处瓦砾成堆。
  • Bacteria sticks to food debris in the teeth,causing decay.细菌附着在牙缝中的食物残渣上,导致蛀牙。
14 stationary CuAwc     
adj.固定的,静止不动的
参考例句:
  • A stationary object is easy to be aimed at.一个静止不动的物体是容易瞄准的。
  • Wait until the bus is stationary before you get off.你要等公共汽车停稳了再下车。
15 patriot a3kzu     
n.爱国者,爱国主义者
参考例句:
  • He avowed himself a patriot.他自称自己是爱国者。
  • He is a patriot who has won the admiration of the French already.他是一个已经赢得法国人敬仰的爱国者。
本文本内容来源于互联网抓取和网友提交,仅供参考,部分栏目没有内容,如果您有更合适的内容,欢迎点击提交分享给大家。
------分隔线----------------------------
TAG标签:   VOA慢速英语
顶一下
(1)
100%
踩一下
(0)
0%
最新评论 查看所有评论
发表评论 查看所有评论
请自觉遵守互联网相关的政策法规,严禁发布色情、暴力、反动的言论。
评价:
表情:
验证码:
听力搜索
推荐频道
论坛新贴