VOA慢速英語(yǔ):世界衛(wèi)生組織：每年數(shù)百萬(wàn)人死于空氣污染

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From VOA Learning English, this is Science in the News.

I’m Anna Matteo.

And I’m Christopher Cruise.

Today on the program, we look at our natural world.

We report on the price of air pollution on human lives. We have details from adifferent report that says last year was one of the warmest ever. We look at the effect wind farms could be having on the severity of ocean storms. And we tell how scientists are hoping to use the power of the ocean to produce energy.

Millions Die Every Year from Air Pollution

The World Health Organization says air pollution is now the world’s single-largest environmental health risk. A new report from the WHO says seven million people died in 2012 because of air pollution. That is more than two times as many as the number estimated in 2008.

Air pollution is an international problem. The World Health Organization says one in eight people die from air pollution, from both inside buildings and outside. It says new information shows air pollution is partly to blame for people dying at an early age from heart disease or stroke. It says other causes of death include cancer and chronic -- or long-term -- diseases of the lungs and breathing passages.

Girls wearing masks ride bicycles amid the heavy haze in Beijing February 22, 2014.

The WHO report says most deaths from air pollution take place in low- and middle-income countries in Southeast Asia and the western Pacific Ocean.About half of the world’s population lives in those countries. Many people who live there use open fires or simple equipment to cook food and heat their homes.

Health officials say 4.2 million people died at an early age in 2012 because of the burning of coal and biomass fuels -- such as wood, crop waste and animal wastes. They say 3.7 million others died in cities and rural areas because of outside air pollution.

Carlos Dora is the WHO’s Public Health, Environmental and Social Determinants of Health coordinator. He says countries must work together to reduce air pollution because what happens in one country can affect lives in another country.

“To resolve this issue, it’s quite important that countries, nations, take action which is more or less coordinated, and the reason for that is the air -- shared.Small particles travel thousands of kilometers, normally around the hemisphere traveling east. So, pollution in one country will affect a number of other countries downwind.”

Dr. Dora says at one time, air pollution was worse in developed countries than in developing ones. But he notes developed countries -- especially Britain and the United States -- have taken steps to greatly reduce air pollution during the past 10 years.

“We know that those interventions work on energy especially. On transportation, better engines, cleaner fuels, more-efficient energy technologies, reduction in the need for use, for the use of energy, insulation of houses, etc. Clean energy, solar, wind, energy that doesn’t use combustion is better than those that do use combustion.”

He says measures that help cut air pollution can be costly. But he says they may save money in the long term by lowering health care costs.

Last Year Was One of the Warmest Ever

The World Meteorological Organization says 2013 was the sixth-warmest year since weather officials began collecting temperature records.

Recently, the United Nations agency released a report called The Status of the Climate. It shows that many extreme weather events took place across the planet last year.

The World Meteorological Organization says 13 of the 14 warmest years on record have happened in this century. And it says each of the past three decades has been warmer than the one before it. A decade is defined as a period of 10 years. The WMO says the 10 year period from 2001 to 2010 was the warmest decade ever measured.

Michel Jarraud is secretary-general of the WMO. He told VOA the temperature records show our planet is growing warmer.

"Since 2001 -- the first year of this new century -- the coldest year that we have observed since 2001 is actually warmer than any year before 1998. So I don’t think this, this can be used in seeing a contradiction of the stop in the climate change. The climate change is not stopping.”

There were low temperatures in parts of the United States and Canada last year. But Mr. Jarraud says that does not mean the Earth is not getting warmer. He says many other areas had higher temperatures than normal.

The WMO climate report provides details of ice cover, ocean warming, rising sea levels and gases linked to climate change. It says these events are all linked, and show that our world is changing.

The report says many parts of Asia received more rain than usual in 2013. And it says Britain received more rain than at any time in the past 250 years.

The report says there was little rainfall in the American state of California, in the Sahel area of Africa and in parts of southern Africa. And it notes extremely dry weather was linked to record high temperatures in Australia.

Michel Jarraud says weather events such as more intense heat and heavier rainfall or snow are what one would expect as a result of human-produced climate change.

Can Offshore Wind Farms Weaken Hurricanes?

Wind energy is one of the fastest-growing sources of new electricity around the world. In 2012, more than 150,000 wind turbines were reported to be operating in 90 countries.

These turbines use wind energy to produce electricity. Many energy experts support wind farms, which are areas where one or more of the turbines are placed. They say wind turbines help protect the environment while producing energy.

Now, researchers say turbines placed in waters near the ocean coast might help lower deaths and damage from ocean storms. Mark Jacobson is an engineering professor at Stanford University in California. He studies hurricanes -- the most severe ocean storm. A report on his recent work appeared in the journal Nature Communications.

Over many years, Mark Jacobson developed a computer program to study air pollution, energy, weather and climate. He recently used the program to answer an important question: Can the severity of hurricane winds be lessened by these offshore wind farms?

The study examined three of the most-powerful hurricanes to hit the eastern and southeastern coasts of the United States in recent years. The computer program showed what would happen if large wind farms with tens of thousands of turbines had been in the path of the storms.

The study found that large numbers of offshore wind turbines could affect hurricanes. Professor Jacobson says he learned that a hurricane’s “surge”could be lowered by up to 79 percent and wind speeds could be cut in half or more. A surge happens when winds traveling a long distance over water push waves over land. These surges can severely threaten life and property.

Cristina Archer of the University of Delaware helped write the report on the study. She says walls or islands can also slow or cut a storm surge. But she says the research shows the wind turbines can also help. Professor Archer says the wind farms could help prevent storm damage while also reducing pollution from fossil fuels.

For example, she noted that placing wind farms near the American state of Louisiana could have helped protect the city of New Orleans from Hurricane Katrina in 2005.

Hurricane Katrina was the most destructive natural disaster in American history. Thousands of people died as a result of the storm.

The study suggests that a wind farm would pay for itself over time. There search says it would do so by making power and by lowering hurricane damage. But there has been political and social opposition in the United States to placing even a few hundred wind turbines offshore.

Professor Archer says policymakers, emergency officials and the wind industry could develop partnerships. She says this could lead to new power and protection for coastal areas, and save lives.

Using Ocean Waves to Produce Energy

An often-ignored form of renewable energy is the power of ocean waves.American scientists say energy from the movement of large amounts of water could provide low-cost electricity and drinking water for coastal communities.

The endless line of waves hitting a coastline represents a seemingly never-ending source of energy. But it is not easy to capture that energy because the water in waves moves up and down. It is not easy to turn this movement into a force pushing only one way -- like a river or a blowing wind.

Scientists in California have created an underwater device that they believe solves the problem of capturing the movement of the waves. They think it may also solve another problem -- making drinking water from ocean water.Marcus Lehman is a researcher at the University of California, Berkeley.

“Our device has the advantage that we do not directly convert into electricity. We can decide ourself if we want to produce fresh water or electricity.”

Their device moves up and down, just as the waves do. It creates pressure,bringing seawater towards the coastline. This pressurized water can be used to operate turbines, which then create electricity. Or it can be pushed through special filtering equipment that removes the salt and creates fresh water.

Marcus Lehmann says larger versions of the device could provide power to small coastal areas. He says the ocean could meet growing demand for electricity.

“So in general the available resource of wave energy is in the order of 15 percent of the global energy demand -- which is a lot.”

This Science in the News was written and produced by Christopher Cruise.

I’m Anna Matteo.

And I’m Christopher Cruise.

Join us again next week for more news about science on the Voice of America.