VOICE ONE:

This is SCIENCE IN THE NEWS in VOA Special English. I'm Bob Doughty.

VOICE TWO:

And I'm Faith Lapidus. This week, we will tell about an agreement to limit temperatures in Earth's atmosphere. We will tell about an incident that brought attention to climate change disputes. And we will report on a study of China's giant pandas.

(MUSIC)

VOICE ONE:

The World Meteorological Organization says 2009 was probably the fifth warmest year since 1850. It also says the past ten years may be the warmest ten-year period ever measured.

Controlling rising temperatures was the subject of an international conference last month in Copenhagen, Denmark. The United Nations called the conference to replace a 1997 agreement, the Kyoto Protocol. The protocol contains measures designed to fight climate change.

VOICE TWO:

Almost 200 countries were represented at the conference. In the end, only five of them were able to negotiate an agreement. They are Brazil, China, India, South Africa and the United States. The agreement is known as the Copenhagen Accord. It asks major polluting countries to voluntarily reduce gases linked to what scientists call the greenhouse effect.

Scientists say Earth's atmosphere acts like a greenhouse. Carbon dioxide and other gases in the atmosphere trap heat from the sun. They prevent the heat from escaping into outer space. This balanced system makes it possible for plants, animals and people to survive on Earth. However, the balance is changing. Human activities are producing increased amounts of carbon dioxide and other gases. Burning fuels like oil and coal is a major cause. Clearing forests for agriculture is another.

VOICE ONE:

The Copenhagen Accord sets a goal of 100 billion dollars a year in aid to help poor nations with climate control by 2020. The accord states that limiting temperature increases to no more than two degrees Celsius is necessary to stop the worst effects of climate change.

Many small nations wanted a stronger agreement. One hundred nations supported a target of keeping temperature increases below 1.5 degrees. The nations also say they regret that the Copenhagen Accord has no force of law. Instead, it is voluntary.

VOICE TWO:

China vetoed proposals calling for 50 percent cuts in greenhouse gases. It also vetoed 80-percent cuts by developed countries by the middle of the century. Chinese Premier Wen Jiabao praised the accord. He said that his government took an important and helpful part at the conference.

Environmental activists said the accord is a declaration that small and poor countries are not important. The representative from the Pacific island nation of Tuvalu made an emotional appeal for a treaty with legal force. Tuvalu is the world's second smallest country. Rising seas and warming conditions threaten its existence.

Lumumba Di-Aping was the chief negotiator for G-77, a group of mostly poor countries. He said the agreement is, in his words, a suicide pact.

VOICE ONE:

British Prime Minister Gordon Brown criticized the negotiation process at the conference. But both he and U.N. Secretary-General Ban Ki-moon said the agreement provides a hopeful beginning.

The administration of President Obama says the Copenhagen Accord represents progress. Some reports say the president was responsible for a compromise that made the accord possible. Without his efforts, the reports say, other countries would have gone home without any agreement.

The United States and China are the biggest producers of greenhouse gases. Some commentators say both sides acted in recognition of political conditions in their countries. For example, President Obama wants Congress to take steps against global warming. But the American economy is weak, and 2010 is an election year. Political observers say the idea faces strong opposition.

(MUSIC)

VOICE TWO:

Last year, an incident in Britain brought attention to disagreements about climate change. Private e-mails and other documents were hacked from the Climatic Research Unit at the University of East Anglia. The stolen materials included more than 1,000 e-mails and 2,000 documents. The information was placed on the Internet. Police are investigating the thefts. The university opened an investigation of the Climatic Research Unit. The head of the C.R.U., Phil Jones, temporarily left his position.

VOICE ONE:

The stolen materials intensified questions about global warming. Are climate changes real? If so, were human activities mainly to blame? Most scientists involved in climate research answer "yes" to both questions. Even opposing scientists say human-influenced global warming has become widely accepted by the scientific community.

Some scientists, however, do not believe the evidence for warming. Or, they say the Earth may be warming, but human activity is not responsible.

Instead, these experts say, our planet is experiencing a normal series of temperature changes. They say such changes are events that have always happened.

VOICE TWO:

American researcher Patrick Michaels questions the evidence supporting human-influenced global warming. He said the stolen e-mails prove that the evidence is not correct.

Critics also noted an e-mail written more than ten years ago by Professor Jones of the C.R.U. In the e-mail, he used the words "trick" and "hide the decline" when writing about a graph showing rising temperatures. The image appeared in several scientific publications.

The critics say his wording showed purposeful misrepresentation. But other experts offered technical explanations of how the wording was not meant to hide a drop in temperatures. They say the word "trick" can mean a shortened and effective way to express complex findings.

VOICE ONE:

A few of the stolen e-mails showed open dislike for scientists who oppose the idea of human-influenced global warming. American scientist James Hansen suggested that some of the e-mails showed poor judgment. But he said such comments should be separated from the scientific research.

(MUSIC)

VOICE TWO:

Finally, an international group of researchers has produced a map of the panda's genetic material. Scientists from the Beijing Genomics Institute led the study. The genetic map, or genome, of the panda is the first for a member of the bear family. And, it is the second genome for a member of the Carnivora group, after dogs. A report about the study was published last month in Nature magazine.

VOICE ONE:

Scientists have long known that giant pandas mainly eat just one kind of plant: bamboo. The animals are also known for a low rate of reproduction.

Pandas are also threatened by a loss of land and illegal hunting. It is estimated that less than 2,000 of the animals live in the wild. They are mostly found in southwestern China. Another 120 pandas live in zoos and research centers, mainly in China.

VOICE TWO:

The researchers identified the genetic structure of a three-year old female panda named Jingjing. The study showed that pandas have been in existence for up to three million years. Yet their genetics have caused pandas to develop more slowly than human beings and other mammals.

Pandas are a subspecies of Ursidae, the bear family. But the study showed a high genetic similarity between pandas and dogs. The panda genome is smaller than the human genome. The human one has about three billion base pairs of deoxyribonucleic acid. The panda genome has about 2,500 million base pairs.

VOICE ONE:

Another finding was that the panda's genetic material differed in many places. Researcher Jun Wang says this tells scientists that the decrease in the panda population is not a result of inbreeding. Mating by individuals with similar genes was thought to be a problem.

One unusual finding was the structure of the panda's taste gene. This, scientists say, can affect the ability to taste meat and other foods high in protein. Because pandas likely have all the genes needed for breaking down meat, scientists believe an inability to taste meat may have led to their all-bamboo diet.

(MUSIC)

VOICE TWO:

This SCIENCE IN THE NEWS was written by Jerilyn Watson and Brianna Blake, who was also our producer. I'm Faith Lapidus.

VOICE ONE:

And, I'm Bob Doughty. Join us again next week for more news about science in Special English on the Voice of America.

accord: a formal agreement between two organizations, countries, etc. 协议；条约

genome: the complete set of genes in a cell or living thing 基因组；染色体组

deoxyribonucleic acid: 脱氧核糖核酸

Related stories:

How Earth is cracked like a giant eggshell

Time -- one of the great mysteries of our universe

In Egypt, King Tut's tomb getting a makeover

How you look in pictures tells a lot about you

(来源：VOA 编辑：陈丹妮）