VOA标准英语2011--Mega-Fires Pose Threat to Environment, E

Mega-Fires Pose Threat to Environment, Economy

Experts gathered this week in Sun City, South Africa, to discuss wildfires. But a new report also focused on a growing phenomenon called mega-fires.
The report describes mega-fires as "extraordinary conflagrations¹ unprecedented² in the modern era for their deep and long-lasting social, economic and environmental impact. They're ignited with the help of climate change and may contribute to it as well.
"As a consequence of climate change, climates are getting dryer³ in many parts of the world. And by becoming dryer, the risk of a fire increases. And [in] most of the mega-fires which we looked at, drought was a contributing factor," said Pieter van Lierop, forestry⁴ management officer for the U.N. Food and Agriculture Organization, the FAO.
Black Dragon
The FAO commissioned the mega-fire study. The research was led by Jerry Williams, former national director of Fire and Aviation Management of the U.S. Forest Service. He's credited with the concept of mega-fires.
It's believed the mega-fire era began in 1987 with China's Great Black Dragon Fire. The flames killed more than 200 people and blackened 1.2 million hectares. Scientists still find it difficult to calculate the loss in biodiversity or the amount of greenhouse gas emissions⁵ released.
Van Lierop, who took part in the study, said the emissions are believed to contribute to climate change.
"The other side of the story is how fires or mega-fires, in general, contribute to climate change through carbon emissions. It seems to all of us there's a very logical relation, but we don't have hard statistical⁶ data."
Nature or man?
The study says firefighters often have little chance of controlling mega-fires until they get a favorable change in the weather or the fire begins to run out of fuel. Mega-fires are not always a single wildfire. They can be a complex of fires inter-acting over a wide area.
While the fires are often perceived as an "accident of nature," that's often not the case.
"Mega-fires, like most other wildfires, are in most cases caused by man – on purpose or out of neglect. There are many reasons for this," said van Lierop.
Other factors include poor forest management and a lack of awareness⁷ among the population of the causes of wildfires.
The FAO study examined mega-fires from 1997 to 2010 in eight countries: Indonesia, Brazil, the United States, Greece, Botswana, Australia, Russia and Israel.
The Indonesian mega-fire in 1997 was an act of arson⁸ and burned nearly 10 million hectares. A hectare equals 10,000 square meters. It's estimated the fire also pumped 700 million tons of greenhouse gas emissions into the atmosphere.
More to come
The report said urgent action is required because mega-fires are becoming more common.
"If we know that drought is one of the main contributing factors to the mega-fires, and we know that we're getting to a time of climate change where many parts of the world the climate will become dryer, we can expect a lot more mega-fires than we've had until now. Unless, of course, we look at ways [of] how we can better deal with vegetation of forest and landscape in general by maintaining them in a different way and treating them in a different way," said van Lierop.
For example, the building of communities, road systems and recreation areas as part of logging and mining operations lead to efforts to prevent or suppress fires. However, these developments may be located in areas where fires have played a major ecological⁹ role over the centuries. Flammable natural materials build up, setting the stage for mega-fires.

1 conflagrations   

n.大火（灾）( conflagration的名词复数 )

参考例句：

• Friction makes sparks and sparks start great creative conflagrations. 摩擦产生星星之火，星星之火点燃伟大创意的燎原巨焰。 来自互联网

2 unprecedented   

adj.无前例的，新奇的

参考例句：

• The air crash caused an unprecedented number of deaths.这次空难的死亡人数是空前的。
• A flood of this sort is really unprecedented.这样大的洪水真是十年九不遇。

3 dryer   

n.干衣机，干燥剂

参考例句：

• He bought a dryer yesterday.他昨天买了一台干燥机。
• There is a washer and a dryer in the basement.地下室里有洗衣机和烘干机。

4 forestry   

n.森林学；林业

参考例句：

• At present, the Chinese forestry is being at a significant transforming period. 当前, 我国的林业正处于一个重大的转折时期。
• Anhua is one of the key forestry counties in Hunan province. 安化县是湖南省重点林区县之一。

5 emissions   

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。

6 statistical   

adj.统计的，统计学的

参考例句：

• He showed the price fluctuations in a statistical table.他用统计表显示价格的波动。
• They're making detailed statistical analysis.他们正在做具体的统计分析。

7 awareness   

n.意识，觉悟，懂事，明智

参考例句：

• There is a general awareness that smoking is harmful.人们普遍认识到吸烟有害健康。
• Environmental awareness has increased over the years.这些年来人们的环境意识增强了。

8 arson   

n.纵火，放火

参考例句：

• He was serving a ten spot for arson.他因纵火罪在服十年徒刑。
• He was arraigned on a charge of arson.他因被指控犯纵火罪而被传讯。

9 ecological   

adj.生态的，生态学的

参考例句：

• The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
• Each animal has its ecological niche.每种动物都有自己的生态位.