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Our World — 17 November 2007


MUSIC: "Our World" theme

Straight ahead on "Our World" ... Fighting the high cost of HIV/AIDS drugs ... a greenhouse gas that could amplify the effects of global warming ... And a cloned monkey embryo raises the prospect of duplicate humans.

LANZA: "Nobody in the field wants to clone an entire human being. So, it's only going to be a matter of time before you see a paper showing that this works in the human system."

Those stories, Hurricane Katrina's big carbon footprint, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

American scientists have cloned a monkey and then used the resulting embryos to grow valuable stem cells. The development is the first time a primate embryo has been created in the laboratory, leading experts to speculate that it's just a matter of time before human embryos are cloned to treat disease. VOA's Jessica Berman reports.

BERMAN: Researchers at Oregon Health and Science University used the DNA of skin cells from rhesus macaque monkeys to create embryos from which they extracted stem cells three days later.

In earlier research, the team successfully cloned mouse embryos.

Stem cells are master cells that scientists say can be coaxed to grow into any tissue in the body, making them valuable as a tool for potentially treating or curing human disease.

Robert Lanza is chief of Advanced Cell Technology, a biotechnology firm in Massachusetts.

LANZA: "It's enormously important and a giant step toward showing that human therapeutic cloning is indeed possible. And it proves once and for all that primate cloning is not impossible as many had thought."

BERMAN: In a study published in the journal Nature, researchers describe how they used 304 eggs from 14 rhesus monkeys before they succeeded in creating two embryos from which they grew the two stem cell lines.

Supporters of therapeutic stem cell research say the goal is not to make identical copies of animals, but to create embryos so organs can be grown from scratch using the stem cells.

Experts say the tissue grown from embryonic stem cells could potentially provide desperately needed organs to people who need transplants. They say such organs could also be matched to the recipient so the transplanted organ is not rejected.

Robert Lanza says the fact that a primate embryo has now been created means the cloning of a human embryo is a virtual certainty.

LANZA: "I think the race indeed is on for cloning human embryos for generating patient specific cells. Of course, nobody in the field wants to clone an entire human being. So, it's only going to be a matter of time before you see a paper showing that this works in humans."

BERMAN: The field of embryonic stem cell research has been marked by controversy. South Korean scientist Hoo Suk Hwang claimed falsely in 2004 to have created the first cloned human embryos, setting back the field.

And in the United States, opponents, led by President George W. Bush, feel strongly that it is wrong to use human embryos in this way. The opposition has led Mr. Bush to block attempts to expand federal funding for embryonic stem cell research. Jessica Berman, VOA News, Washington.

One of the great challenges facing poor countries trying to grapple with the AIDS epidemic has been the high cost of the drugs used to treat the disease. Anti-retrovirals remain expensive, even as they've become more widely available. Adding to the expense of AIDS drugs is the fact that patients need to take them for the rest of their lives. Details, now, from our health reporter, Rose Hoban.

HOBAN: Low-income countries have been helped by an international movement to reduce the price of anti-retrovirals or produce generic drugs to replace expensive brand-name medications. Generic drugs contain the same ingredients as brand-name drugs, but they're made by other companies and sold at lower cost.

Amy Nunn, a researcher at the Harvard School of Public Health, says that Brazil has been a worldwide leader in producing generic versions of drugs to treat AIDS.

NUNN: "Brazil has been producing generic drugs since the 1950s, and Brazil actually began producing generic AIDS drugs in the early 1990s. The first generic AIDS drugs in Brazil were actually manufactured in the private sector, and the technology was transferred to the Health Ministry."

HOBAN: In a recent issue of the online journal Public Library of Science: Medicine, Nunn traces the history of Brazil's effort to provide drugs for its AIDS patients.

NUNN: "Brazil said if you don't lower your prices, we will produce this drug locally and this will be legal under the World Trade Organization TRIPS agreement from 1995. Everything that Brazil has done has been legal, but they've gone about this entire strategy in a very clever way."

HOBAN: Nunn says this strategy has had a positive impact on AIDS patients in Brazil.

NUNN: "What this means is that Brazil has been able to provide antiretroviral drug treatment to over 180,000 people living with HIV/AIDS."

HOBAN: Nunn notes for the treatment program has helped more patients than in any other developing country with comparable drug programs for AIDS patients. And Nunn estimates that Brazil has saved over $1 billion on AIDS drugs, just since 2001.

But Nunn adds that prices for generic anti-retrovirals have been rising over the past few years. She says these rising prices will continue to produce challenges for Brazil as it tries to meet the needs of patients with AIDS. I'm Rose Hoban.

Brazil, of course, is home of the Amazon, where vast tracts of rain forest take in the greenhouse gas, carbon dioxide, and store it in the trees' wood fiber. As long as a tree lives, the CO2 stays safely in its fiber, where it does not contribute to global warming.

If the tree dies naturally, the carbon will eventually be released as bacteria and fungi — the decomposers — do their thing. The release of that carbon, in a process called flux, can contribute to global warming.

Jeff Chambers of Tulane University in New Orleans has been studying the process of carbon cycling in forests, mostly in the Amazon. But two years ago, when hurricane Katrina slammed into the U.S. Gulf Coast, he wondered about the impact of the storm on the carbon cycle, and figured out a way to combine data on the ground with satellite data in the same way he had been doing in Brazil. I reached Professor Chambers between flights at the noisy airport in Sao Paolo, Brazil, and I asked him to explain how he came up with the idea.

CHAMBERS: "So, while I was evacuated I thought, you know the exact same tools that I'm applying to look at wind disturbances in the Amazon could be applied to this Katrina question."

Q: And the methodology was pretty unusual. Can you describe it briefly?

CHAMBERS: "Sure. Usually when somebody wants to set up a forest inventory plot they go into the forest and they walk around and they say, okay I'll put a plot right here. And sometimes they might characterized the area with some ground surveys. But what we did was first, we analyzed satellite data to develop a metric of the gradient of the disturbance. So from the least disturbed sites to the most disturbed sites. And then we used that measure from the satellite data to direct our field sampling. And then in the field what we did was developed a relationship between the number of trees that were damaged or that died in the event with that satellite metric. And that allowed us to statistically extrapolate our ground measurements to the entire footprint of Katrina."

Q: So you did that, and what did you find?

CHAMBERS: "Well, we were surprised to discover that the number of trees that died or were severely damaged by the storm, that essentially, you know, live trees have a certain amount of carbon that they store, primarily in the wood and tissues of the tree. And the wood of the tree, that's were most of the carbon is stored. But the tree, the live tree, essentially protects that carbon from being eaten by the decomposers. And so when you get this big flux of wooden material from this live pool to the dead pool, it's consumed by the decomposers and that results in a carbon flux to the atmosphere. So what we found was these hundreds of millions of trees that either died or were severely damaged, the flux that will be associated with that dead pool will be more than all U.S. forest trees sequestered in one year, essentially. So that flux essentially offsets the gains in all the other forests of the U.S."

Q: Three hundred million trees or thereabouts is an enormous number. It certainly opened my eyes. Was that a surprising number to you? You work in this field.

CHAMBERS: "Yeah. It was very surprising. We expected there to be, you know, a significant number of trees that were impacted by the event. But for the number of trees to, essentially, offset all the other gains in all the other forests in the U.S. was pretty surprising. In fact, we had to re-do the analysis in five or six different ways using five or six different, you know, approaches to check and validate our results before we were convinced that this is the number."

Q: Can you put this in context? You're talking about a carbon sink — storage, essentially, of carbon. But how does the number that you came up with relate to the amount of carbon emissions that we get from power plants and vehicles and that sort of thing?

CHAMBERS: "Yeah, that's interesting, Art. To put that into context, the U.S. global emissions each year is something like 8 petagrams, and what we found was something like a tenth of a petagram, plus. [1 petagram = 1 billion metric tons.] So in terms of fossil fuel emissions, it's pretty small. But in terms of forest impact, and particularly by a single storm, it's pretty significant."

Prof. Jeff Chambers of Tulane University in New Orleans. His paper on the carbon footprint of hurricane Katrina was published this week in the journal Science. We reached him at the airport in Sao Paolo, Brazil.

And stay tuned, we'll have more on climate change later in Our World, but first ...

It's time again for our Website of the Week, when we showcase interesting and innovative online destinations.

Poetry probably doesn't have the prominence in American culture that it once had, or maybe that it still has in your country. But at our Website of the Week, they're not only keeping poetry alive, they're working to make it a vibrant part of 21st-century life.

WARN: "The Poetry Foundation seeks to find great poetry and place it before the largest possible audience. The goal of our website is to reach people with poetry on the Internet. We have an archive of 6,000 poems by more than 600 poets writing in English, and we try to get those poems all over the world."

Emily Warn is a poet, of course, and editor of PoetryFoundation.org. The Poetry Foundation is the publisher of Poetry magazine, which was founded in 1912, but now they're bringing a world of poetry to anyone with an Internet connection.

To find a favorite poem, or to help you discover a new one by a particular poet or on a particular topic, she suggests using the feature they call the Poetry Tool.

WARN: "For every single poem in our archive we've indexed them or categorized them according to a set number of categories. So: love poems, or sonnets, or nature poems, or poems about philosophy. And this has proven very successful. We deliver a huge number of poems every day to people."

The site also includes many other features, including a podcast, called Poetry Off the Shelf, and several other useful multimedia offerings.

WARN: "We also have an audio poem of the day that you can sign up for. We also are going to be launching a series of educational podcasts, similar to an audiobook. These will be very, very long podcasts that you can download and play in your car as you're driving and actually learn about poetry if you're interested in it and didn't have a chance to study it in school."

And Emily Warn says they've just posted their first video, featuring the new American poet laureate, Serbian-born Charles Simic.

A lot of readers are scared off by poetry. You don't have to be. Dig in to our very accessible and user-friendly Website of the Week, PoetryFoundation.org, or get the link from our site, voanews.com/ourworld.

MUSIC: La Bouche — "Poetry In Motion"

The reporting is solid and the writing is clean
on VOA's science and tech magazine.

It's Our World. I'm Art Chimes in Washington.

When it comes to greenhouse gases, you probably know about carbon dioxide. Maybe you know about the more potent effects of methane. But it might surprise you to learn that the biggest contributor to the greenhouse effect is water vapor.

Prof. Brian Soden of the University of Miami says unlike other greenhouse gases, the amount of water vapor in the atmosphere is not a direct result of activity on Earth.

SODEN: "Well, I think part of the reason that it's not hit the radar screen is because water vapor is a natural gas. The warmer the planet is, the atmosphere naturally holds more water vapor. And because of that, that in turn acts to amplify the surface warming even further because water vapor is such a powerful greenhouse gas."

Soden says water vapor accounts for 60 percent of the greenhouse effect, compared with 25 percent for carbon dioxide.

Now, a little greenhouse effect isn't a bad thing. Without it, heat would escape back out into space and Earth's average temperature would be about 30 degrees colder. The problem is that human activities — mainly burning fossil fuels like coal and oil — are increasing the concentration of greenhouse gases, leading to higher average temperatures on earth. That, in turn, could lead to a rise in sea level and other potentially disastrous consequences.

Soden says water vapor intensifies the impact of global warming.

SODEN: "As the Earth warms from increasing CO2, that additional warming creates more water vapor in the atmosphere. That additional water vapor in the atmosphere further amplifies the greenhouse effect. The stronger greenhouse effect heats the surface even further, and so you get into this feedback loop. But it's important to understand that water vapor doesn't initiate change, it acts to amplify that change. And that change can either be amplifying a warming trend from increasing CO2 or it can amplify a cooling event from, say, a La Niña or from a volcanic eruption."

Soden was one of several climate scientists who spoke at a recent seminar on Capitol Hill sponsored by the American Meteorological Society.

Climate scientists create models — computer simulations — of future trends based on what they know about how climate works. Each model is a little bit different, so they sometimes arrive at different projections of what will happen in the future. But Francis Zwiers of the Canadian government agency Environment Canada, says the models generally agree on how rising temperatures will affect rainfall and other precipitation.

ZWIERS: "So there's pretty strong consensus that we're going to get in the future more precipitation than at present at high latitudes, more precipitation on the equator, less precipitation in the dry subtropical regions that are already dry. So the wet will get wetter and the dry will get dryer. And we're seeing some evidence in the climate system that this is already happening."

That's what the Intergovernmental Panel on Climate Change suggested earlier this year

Researchers trying to get a handle on water vapor in the atmosphere and other aspects of climate change science say they are hampered by the lack of proper tools. Among them is Frank Wentz, whose company, Remote Sensing Systems, analyzes satellite data.

WENTZ: "If climate change is important, then this nation needs to step up to the plate and have some agency take the responsibility to study, measure and understand the climate. Right now it's sort of done partly by [the space agency] NASA, partly by NOAA [National Oceanic and Atmospheric Administration]. We have to piece together [data from] satellites that weren't designed to actually measure the climate. We're going to Mars right now. I think it's great to go to Mars but I think we have a higher priority, and that is to understand the planet we live on."

If climate change is a global problem, its effects will be felt locally, and nowhere more so than in the world's poorest countries — countries without the infrastructure to cope, countries whose residents already often live life close to the edge. At Columbia University in New York, experts gathered recently to consider the threat posed to developing nations in a warmer future. VOA's Adam Phillips was there.

PHILLIPS: More than 100 scientists and government policymakers focused on a wide range of issues: from hunger, poverty, and disease to poor education, bad water, inadequate sanitation, and more. But everyone agreed that climate change connects all these seemingly unrelated woes.

Haresh Bhojwani, of the International Institute for Research into Climate and Society, says that coping with the immediate effects of extreme weather events is especially difficult for poor nations. So, for example, when a massive hurricane hits…

BHOJWANI: "It means there are fewer ambulances in place to get to affected people. The roads are not built to withstand the type of event that just occurred, there are not the markets in place to get the food and the blankets, the basic requirements into place to help people."

PHILLIPS: Bhojwani adds that when one system of infrastructure breaks down, other systems can become overburdened, creating a downward spiral of dysfunction.

BHOJWANI: "Instead of having a very scary situation from which you recover a few days later because you have the resources in place to get people to hospitals, to get the neighborhoods back on their feet, to get villages back into production, you end up with a prolonged impact that can last [for] years."

PHILLIPS: Drought is a worsening worldwide problem. In Central and South America, for example, where the economies of over half the nations depend on agricultural exports, drought means a drop in foreign trade and exchange. Latin America depends on hydroelectric dams for more than half of its energy. When river levels fall, the cost of energy skyrockets, with potentially dire consequences for the region's economy.

Global warming may also be causing a significant increase in malaria, which kills up to two several million people annually.

PHILLIPS: In the United Republic of Tanzania, in southern Africa, the famous glacial snows of Mount Kilimanjaro are melting away. When it comes to responding to climate change in the developing world, Augustine Mahiga, Tanzania's ambassador to the U.N., draws an important distinction between short-term "mitigation" efforts and long-term adaptations.

MAHIGA: "Mitigations are short term measures to cope with the consequences that are manageable, like food shortages, droughts. But longer-term adaptation means transfer of appropriate technology that would, for example in the agricultural sector, entail high-yielding seeds, or developing such a seed technology in the country. It would entail new methods of water preservation, like extensive irrigation schemes, which are not [yet] there."

PHILLIPS: Mahiga says nations trying to respond to climate change would also have to consider the rising cost of energy and fuel in the world.

MAHIGA: "Because if you are addressing the agricultural sector, you need tractors which consume diesel; you need fertilizers which are derivatives of hydrocarbons. And the price of all these is going up and up. And for a country like Tanzania, which has 12 hours of sunshine every day, solar [energy] would be a most appropriate alternative. These are long term measure that would need additional funding. We need resources."

PHILLIPS: Experts at the Earth Institute's conference on Climate Change and Millennium Development Goals agreed that economics and politics are key factors in the global climate challenge. U.S. climate policy under President George W. Bush has resisted collective responses that could threaten American business interests. But developing nations contend that because the U.S. and other industrialized countries produce most of the greenhouse gases associated with climate change, they have a responsibility to share their expertise and financial resources with poorer nations which are most likely to bear the brunt of global warming. I'm Adam Phillips reporting from New York.

MUSIC: "Our World" theme

That's our show for this week. If you'd like to get in touch, email us at ourworld@voanews.com. Or use the postal address —

Our World
Voice of America
Washington, DC 20237 USA

Rob Sivak edited the program. Eva Nenicka is the technical director. And this is Art Chimes, inviting you to join us online at voanews.com/ourworld or on your radio next Saturday and Sunday as we check out the latest in science and technology ... in Our World.

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