NEREM: "And that is still very uncertain, which is why a paper like this is very interesting. Because we are really just now starting to get a handle of what the dynamics of these ice sheets are and the question is, they are almost certainly going to melt, but how quickly are they going to melt; you know, how much is going to melt in 100 years, in 1,000 years or 2,000 years."
If the entire Greenland ice sheet were to melt, Nerem says it contains enough water to cause a global sea-level rise of seven meters. For low-lying countries to prepare, Nerem says, scientists need to know how quickly the Greenland ice mass is melting.
NEREM: "If the meter in sea level rise were to happen very rapidly, say in 50 years, it will be very hard to build the infrastructure, you know the dykes – and the other things to hold back the water – quickly enough to prevent the inundation that would occur with a meter of sea-level rise. If it were to take hundreds of years, then that would probably be enough time for populated areas to build the protections that they need to combat this."
New measurements of sea level rise and ice loss in Greenland are published this week in the journal Science.
Site Tracks Global Warming Emissions Country by Country
A new website was launched in Barcelona last week, at the close of the final round of climate negotiations prior to Copenhagen. It's designed to help make the climate talks more accessible to the general public… and it's our website of the week. Climateactiontracker.org is a collaboration among two German-based research groups and the Potsdam Institute for Climate Impact Research. The website presents the proposed emission targets of 49 countries… and considers whether they keep global climate change at a safe level or not.
Niklas Hohne is Director of Energy and Climate Policy for Ecofys, one of the site's developers. He advises visitors to start on Climateactiontracker's 'Top-Ten' page.
HOHNE: …where we have ranked the countries in the different categories, and you will find a few countries in the sufficient category, a few in the medium category and unfortunately quite a few in the inadequate category.
…which means they are not planning enough reductions to curb global warming. Climateactiontracker.org collected data for 22 nations and the 27 countries in the European Union. Hohne says once all the information was compiled, a different picture emerged than what was expected.
HOHNE: "Most of the big developing countries, we rated them in the medium category. Most of the developing countries have quite ambitious plans on the table. We also found two countries which we categorized above sufficient, which is a role model. That's the Maldives and Costa Rica, which are two countries that want to be climate-neutral by around 2020."
That was the most ambitious goal set overall, even among industrialized nations. Hohne says climate data was harder to get for the world's poorest countries.
HOHNE: "Only a few developing countries provide future emission projections and the impact of their plans on total emissions so we had to aggregate them ourselves and that data quality is certainly a bit weaker. It would be much better that if the countries themselves would do that work."
South Korea and Brazil are expected to announce new emissions reduction targets soon. Hohne says those numbers will be posted on the climateactiontracker.org website, along with any other country announcement in the run-up to the Copenhagen summit.
Access to Clean Water Critical for HIV Care
In health news this week, we turn to the American Public Health Association meeting in Philadelphia, where Rose Hoban takes a closer look at HIV care in developing countries. While primarily focused on getting people access to medications and treatment, she explains that care can't be effective without clean water.
Rose Hoban reports:
There are some basic requirements to keep people with HIV healthy: good food to help them retain weight, medications to treat the virus, and clean water. But Renuka Bery, from the NGO Academy of Educational Development, says in many instances, people living with HIV in resource poor countries lack the most basic of these – access to good water.
BERY: "And it's kind of ironic, when you're taking anti-retrovirals and you're drinking it down with dirty water, and it will give you diarrhea. And also the anti-retrovirals will also induce diarrhea as well. And if you have a weakened immune system, the more diarrhea you have, the weaker you get, the less nutrients you get, so it becomes kind of a vicious circle.
Bery recently worked on projects in Ethiopia and Uganda to help people with HIV and their caregivers reduce the incidence of diarrhea, with better hand washing and water treatment. She and her colleagues came up with simple methods that these people could use to practice better sanitation.
One intervention, for instance, was teaching people how to make a 'tippy tap' for hand washing out of things usually thrown away.
BERY: "You can take a bottle, you can poke a hole and stick a straw in it and the pressure from opening the cap and closing the cap regulates the flow of water. So when you close it up, water stops flowing, when you open the cap, the pressure releases, and the water comes out. Voila, you have water-saving hand washing device, starts flowing. With just a few drops of water, you can wash your hands with soap or ash."
This method is far superior to the way that many people end up rinsing… by dipping their hands into water that's already been contaminated. Bery says health workers know that some methods of sanitation are ideal, but out of reach for people in such poor situations. So they coached HIV patients and their families to make incremental improvements:
BERY: "We've developed some materials where a health worker who's visiting a household, or a home-based care worker can take a chart and say, well, do you do open defecation? And then if you do that, do you think you could dig a pit and put your feces in a pit…? Digging a hole and putting it into the hole is better than nothing."
Bery says by teaching people with HIV and their caretakers simple methods to enhance sanitation, they improved the health of the patients – and the people around them. For example, better hand washing decreased diarrheal disease in patients with HIV by almost one half. Bery presented her project report at the annual meeting of the American Public Health Association, where this year's theme was 'Water and Public Health.'
Study Provides New Evidence for Genetic Basis of Language
The ability to communicate using complex spoken language is a uniquely human characteristic, but surprisingly little is known about how we developed language when our close primate relatives, like chimpanzees, did not. As Veronique LaCapra reports, a single gene may hold a big part of the answer.
Veronique LaCapra reports:
Dan Geschwind is a professor of neurology, psychiatry and human genetics at the University of California in Los Angeles.
GESCHWIND: "We don't know that much about how language evolved in humans, but it clearly is going to reside in changes in genes: either new genes, or changes in old genes that gives them new functions."
Genes carry hereditary biological information that determines much about who we are – from our height to our hair color to which hand we use to write with. Geschwind has been studying the function of one particular gene, called FOXP2.
GESCHWIND: "It's one of the few genes that's been very clearly tied to the capacity for human speech and language. And FOXP2 works in an interesting way. It's a kind of regulator gene, it turns other things on and off."
Specifically, it regulates other genes. In a cell, FOXP2 acts like a master switch, producing a protein that binds to other genes and increases or decreases their activity. In spite of FOXP2's apparent role in human speech, it turns out that our FOXP2 protein is almost identical to the version found in our closest primate relative, the chimpanzee.
GESCHWIND: "A protein like FOXP2 is made up of hundreds of amino acids, and just two of them are different between human and chimpanzee."
Previous work by other researchers had suggested that the amino acid composition of the human FOXP2 protein may have changed at about the same time in evolutionary history that humans started to speak. Could a difference in just two amino acids trigger enough changes in downstream gene function to create the capacity for language?
Genevieve Konopka, a postdoctoral fellow in the Geschwind lab, led a study to look into this question. Konopka looked at the effects of FOXP2 on human neurons, or brain cells, in cell cultures in the lab.
KONOPKA: "And so we manipulated these cells to then express [produce] either the human version of FOXP2 or the chimpanzee version of FOXP2. And then we used something called a microarray, which allows you to examine the expression of every gene in the genome."
Konopka found that the human and chimpanzee versions of FOXP2 did function differently in human brain cells, targeting different genes and triggering different levels of gene activity.
Dan Geschwind says similar differences in gene expression were observed in brain tissue samples taken from humans and chimps that died of natural causes. The samples were frozen soon after death to retain the characteristics of living tissue.
GESCHWIND: "We saw a very big overlap in [what the genes were doing] in the cell culture, and in the brains. And this gave us a lot of confidence that what we were actually seeing was relevant to brain function."
Geschwind says that many of the genes and proteins affected by FOXP2 are known to have functions in the brain, but that others may be involved in the development of the physical apparatus of speech, like the larynx and vocal chords.
GESCHWIND: "Because to have spoken language, two things have to happen. One is, there's a kind of change in the vocal anatomy: our vocal chords, tongue, and all of that changed to allow us to speak. But of course the major thing that happened was the changes in the brain that gave us the capacity for language. But these two things are very connected, and it's possible that […] at least one connection is via FOXP2."
Geschwind and Konopka say the next step in their research will be to look more closely at the genes FOXP2 regulates, and to investigate their possible role in disorders affecting speech and language. Their current study is published in the journal Nature.
Brown Pelicans Removed from Endangered Species List
Once on the brink of extinction, the brown pelican was removed this week from the U.S. Endangered Species list. U.S. Secretary of the Interior Ken Salazar called the recovery "a milestone of success."
SALAZAR: "It has taken 36 years, the banning of DDT and a lot of work by the U.S. government, the states, conservation organizations, dedicated citizens and partners, but today we can say that the brown pelican is back."
Hunted for its feathers and decimated by the pesticide DDT, brown pelicans numbered fewer than 10,000 when it was declared endangered in the early 1970s. With Endangered Species protections the population has swelled to 650,000 birds found across the Florida Gulf and Pacific coasts, the Caribbean and Latin America. U.S. Fish and Wildlife Service Director Sam Hamilton says central to its recovery has been a network of national and international partners.
HAMILTON: "We've been funding for 20 years habitat projects, monitoring surveys and tremendous training programs for natural resource managers throughout Latin America. I think that the model is that not any one individual, one agency or one government can actually achieve full recovery of a species that knows no [geographic] boundaries."
The Migratory Bird Treaty will continue to protect the brown pelican its nests and habitat. But U.S. Fish and Wildlife's Sam Hamilton says the birds' habitat is at risk if, as predicted, sea level rises. He says coastal restoration has become a priority in the battle against global warming.
HAMILTON: "One of the key things that we can do and many places like where we are today in coastal Louisiana is try to get the water and sediment right. That's the best defense against coastal marsh loss and brown pelican habitat loss is to try to restore the hydrology, sediment and integrity of those habitats."
In the long run the survival of the brown pelican - and other coastal species - will depend on how species can adapt to changes in coastal or inland habitat. In the de-listing the brown pelican joins other formerly endangered species including the bald eagle and the peregrine falcon.
And, that's our program for this week.
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Faith Lapidus is our editor. Our technical director is Felicia Butler. I'm Rosanne Skirble. Join us online at voanews.com/ourworld or on your radio next week at this same time with Art Chimes as we explore the latest in science and technology on Our World.