Greenland's Glaciers Are Moving Faster, Melting Faster Into the Sea
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This is SCIENCE IN THE NEWS in VOA Special English. I'm Faith Lapidus. And I'm Bob Doughty. This week: Climate warming and the effects on ocean levels ...
The effects of war on soldiers ...
Marriage through sickness and health ...
And fighting chronic diseases.
A new study has examined the loss of ice from glaciers in Greenland. It found that the amount of ice that drops into the Atlantic Ocean has increased almost one hundred percent in the past five years.
Glaciers are slow-moving mountains of ice. Researchers say the ones in southern Greenland are melting faster because they are moving faster. They say rising temperatures appear to be the cause.
The American study used recent changes in glacier speed to estimate the ice loss for almost all of Greenland. The results appeared in Science magazine. They were also reported last month at the yearly meeting of the American Association for the Advancement of Science.
Eric Rignot is a researcher in the Jet Propulsion Laboratory at the California Institute of Technology. He says glaciers take a long time to form and melt, but they can react quickly to temperature changes.
He says he is concerned that current estimates of Greenland's ice loss fail to consider the speed of glacial ice falling into the sea. This means ocean levels could rise faster than scientists have estimated.
Mr. Rignot and Pannir Kanagaratnam of the University of Kansas used satellite observations to confirm the glacial speeds. They found that ice from Greenland is responsible for a rise of about one-half millimeter in ocean levels every year. Worldwide, ocean levels are rising about three millimeters a year.
The air temperature in southeastern Greenland has risen by three degrees Celsius during the past twenty years. For the past ten years, the glaciers in southeastern Greenland have been largely responsible for increases in glacier flow from the island. Mr. Rignot says glaciers farther north have increased speed since the year two thousand. He says the northward spread of mild weather might be responsible.
He also notes that scientists do not yet fully understand the complex processes by which glaciers gain speed.
Social connections are important to a person's health. A study with older people demonstrates this. It shows how the health of one person in a marriage can affect the health of the other.
The study is the largest of its kind to look at how sickness in one person affects the risk of death in the other. It involved more than one million people in the United States. They were between the ages of sixty-five and ninety-eight.
Researchers at Harvard Medical School and the University of Pennsylvania did the study. They examined the effect of a major sickness in one person on the risk of death in a care-giving partner. They also examined the effect of the death of a wife or husband on the risk of death in the other person.
The researchers considered these two effects together. They studied cases where a husband or wife was sick enough to require hospital treatment. They found that some conditions affect a partner more than others do.
For example, the study found almost no effect on a man's risk of death if his wife had colon cancer. But if she had heart disease, the man's risk of death was twelve percent higher than if his wife were healthy. And the risk increased twenty-two percent if his wife were being treated for dementia, a mental disorder.
The scientists say they found similar effects in women whose husbands were being treated. But there was a difference. The scientists found that if a husband became mentally disabled, the effect on his wife was even worse than if he had died.
The study confirmed that sickness or death in one partner has an especially large effect on the other person within the first thirty days. This risk of dying early in reaction to a partner's death is commonly known as the "widower effect."
The New England Journal of Medicine published the results. The research began in nineteen ninety-three and continued for nine years. The National Institute on Aging supported the study.
Paul Allison is chairman of the Sociology Department at the University of Pennsylvania. He says it was surprising that highly deadly diseases, like lung cancer, had little effect on the risk of death for a partner. By comparison, mental disorders led to big increases in the partner's risk of death. The explanation is that having to care for someone with a mental condition places a great responsibility on the partner.
In a separate but related study, Harvard sociologists Felix Elwert and Nicholas Christakis looked at race in connection with the widower effect. They say that while it is common in whites, they saw no effect in African-Americans. They say this could suggest that blacks families are more densely connected and help care for the surviving partner.
You are listening to SCIENCE IN THE NEWS in VOA Special English. Researchers have gone back in time to examine the physical and emotional effects of war on soldiers.
They studied soldiers who fought in the American Civil War. They chose that war because the medical history is complete. All of the soldiers are dead. The Civil War took place from eighteen sixty-one to eighteen sixty-five. The Union army defeated the Confederacy in the South.
Researchers from the University of California, Irvine, did the study. The Archives of General Psychiatry published the results.
The researchers studied medical and military records of fifteen thousand Union soldiers. All of the soldiers received physical examinations before they joined the army. Government doctors also recorded the medical history of soldiers after the war.
Conditions are named in words of the time. For example, doctors used the term "soldier's heart" to describe the physical and emotional effects of the war. Now, they would call it post-traumatic stress disorder.
Military companies with higher rates of soldiers killed had higher rates of disorders among the survivors. The study found that these soldiers were fifty-one percent more likely to develop heart, stomach and nervous system disorders.
The researchers say the youngest men had the worst medical records. These were men who had joined the army when they were seventeen or younger. After the war, the youngest men had the highest risk of dying early.
Some soldiers joined the army when they were as young as nine. Others joined when they were seventy or older.
The researchers say the effects seen in the nineteenth century are likely to be true for twenty-first century soldiers as well.
Professor Roxane Cohen Silver led the study. She says the records show that horrible war experiences are linked to what she calls "a lifetime of increased physical disease and mental health difficulties."
The World Health Organization says chronic diseases lead to about seventeen million early deaths each year. Chronic diseases are the world's leading cause of death. These include heart disease, stroke, cancer, diabetes and lung disorders. The W.H.O. expects them to claim to more than three hundred eighty million lives by two thousand fifteen.
The United Nations health agency says about eighty percent of the deaths will happen in developing nations. Victims are often in their most productive years. Experts point out that more middle-aged people die from chronic diseases in poorer countries than in wealthier ones.
The W.H.O. is seeking international action to reduce deaths from chronic diseases. Up to eighty percent of these deaths are considered preventable. Health officials say one important tool for governments is to restrict the marketing of alcohol and tobacco to young people. Also, more programs are needed to urge healthy eating and more physical activity.
The goal is to save thirty-six million lives by two thousand fifteen.
SCIENCE IN THE NEWS was written by George Grow and Cynthia Kirk. Avi Arditti was our producer. I'm Faith Lapidus. And I'm Bob Doughty. Internet users can read and listen to our programs at voaspecialenglish.com. Join us again next week for more news about science in Special English on the Voice of America.