1742. Desperation Drives Gazans Over a Fence and Into Israeli Prisons

By Jodi Rudoren and Majid Al Wahidi, The New York Times, February 17, 2015

Ibrahim al-Awawda, 15, crossed a fence into Israel and was promptly captured and soon returned to Gaza. Many Palestinian youths have been trying to cross to escape the poverty in the territory. Credit Wissam Nassar for The New York Times

EL BUREIJ, Gaza Strip — It was not much of an escape.

Moments after Ibrahim al-Awawda climbed over the nine-foot fence separating the Bureij refugee camp on Gaza’s eastern edge from Israel, he was surrounded by six Israeli soldiers. They arrested him, interrogated him and, after he spent a month in two Israeli prisons, sent him back to the poverty, death and destruction in Gaza that had led him to flee.

“I knew they would capture me,” said Ibrahim, 15, whose father was killed in an Israeli strike in 2002 and who has since lived through three wars between Israel and Gaza militants, including last summer’s bloody 50-day battle. “The war shook me,” he added. “I told myself I may find a better life. They served me good food, but later, they threw me back to Gaza.”

Ibrahim is one of an increasing number of young Palestinians from Gaza who have been caught trying to cross into Israel in the nearly six months since the latest conflagration subsided. Though he carried nothing with him, others were armed with knives or grenades.

The crossings have shaken residents on Israel’s side of the fence who are still psychologically scarred from the series of tunnel invasions by Palestinian militants that punctuated last summer’s conflict. But military officials and others see the growing phenomenon as less about terrorism than about desperation.

Several fence jumpers, and human rights workers who track their cases, compared their despondency to that of the roughly 300 Gazans who died in a September shipwreck as they were being smuggled across the Mediterranean Sea: They just wanted out, no matter the risk.

Some are shot in the process. Some are harassed upon their return by Hamas, the Islamist faction that dominates Gaza, as suspected collaborators with Israel. Still, many fantasize about finding work in Israel and see even the all-but-inevitable time behind bars as worth it, given that it comes with a monthly stipend the Palestinian Authority pays all its prisoners.

Compared with Gaza, “the prison in Israel is like a five-star hotel,” said Youssef Abbas, 21, who did stints there after crossing the border in 2010 and 2008. He said he headed toward the fence twice more in September but was turned back, once by Gaza security forces and once by a call from his fiancée.

“I was thinking of two choices: death or prison,” Mr. Abbas said. “Because there were so many problems in my life, I was so tired, I had this idea.”

The Israeli military said 84 Palestinians were arrested after hopping the fence from September to January, along with nine more in the first nine days of this month. The military would not provide comparable figures for the first half of 2014 or previous years, but it confirmed a report in the Israeli daily newspaper Haaretz that the prewar monthly average was 13, less than half the 27 arrested in November.

“It’s a slight increase,” said the Israeli military spokesman, Lt. Col. Peter Lerner, “not necessarily a game changer, as far as we’re concerned at this stage.” Still, Colonel Lerner said: “Each and every infiltration we address as a potential terrorist attack. All it takes is for one to come in with a weapon, with a grenade, with a suicide belt and so on. So that’s our concern.”

Separately, the military announced last week that it had destroyed the Israeli side of a tunnel discovered during the summer fight with Hamas.

The military wing of Hamas ran a dozen training camps last month in which 17,000 boys and men aged 15 to 21 learned to climb ropes and fire assault rifles in preparation for the next confrontation with Israel.

For the Israelis living in the tiny communities near the barrier, reports of each illegal crossing are jittery reminders of last summer.

At Kibbutz Sufa, about a mile from where 13 gunmen from Gaza emerged from a tunnel on July 17 — an episode that led to Israel’s ground invasion of Gaza — “people are reliving the fear,” said Eyal Brandeis, a longtime member of the 300-person kibbutz’s emergency team and a professor of political science at Bar-Ilan University.

Rony Kissin, community manager of Kibbutz Kerem Shalom, just half a football field’s length from the fence, said that residents with permits were carrying their pistols more often than before. Children in the community are acting more violently, she said, and mothers are more worried.

“We can’t see them, because we have not just a fence — we have a wall around three-quarters of the kibbutz, so we don’t really see the border,” said Ms. Kissin, 49. “Sometimes I don’t want to know. If the army catches him seconds after he crosses the border, I don’t think I should know, because it really makes the tension more high.”

In Gaza, men who had crossed said Israeli security officials had questioned them, sometimes for hours, about whether Hamas or any other group had sent them, how they had planned their escape, what they intended to do in Israel and, broadly, what was happening back home in the war’s aftermath. When they returned to Gaza, they said, Hamas security officials questioned them, sometimes for hours, about what they had told the Israelis.

Iyad al-Buzom, the spokesman for Gaza’s Interior Ministry, said it had taken “serious measures to prevent border sneaking” since the war and was considering “more harsh procedures and punishments to stop those who think of crossing the fence.” He said officials worried that crossers would be pressured into revealing information to Israeli intelligence upon their arrest, or be hurt as they tried to get to the other side.

Data from the United Nations’ Office for the Coordination of Humanitarian Affairs show that Israeli soldiers killed six Palestinians near the fence in 2014, all but one before the war. That was double the number in 2013, but significantly fewer than the average of 22 annually in the previous four years. Thirty-nine Gaza residents were wounded by Israeli fire and tear gas from September through January, the data show, some while protesting or throwing stones, others while trying to cross.

Ateya al-Nabahin, 15, was shot in the neck as he tried to sneak into Israel in November, and he returned home in January after being treated in two Israeli hospitals. “Now, he is lying on his bed like the dead,” Ateya’s brother, Fadi, said in a recent interview. “He cannot walk or even talk like normal people.”

Looking back, Hasan and Salwa al-Zawara’a see plenty of signs that their 20-year-old son, Noor, was planning to cross before he disappeared Oct. 27 from their home in Johor al-Deek, a village next to the Bureij camp.

Three days earlier, his mother recalled, Noor asked for a copy of his identity card. That morning, he changed clothes several times before settling on jeans and a black shirt. He had almost never had a decent night’s sleep since the war, his father said, and he had been asking a sister’s husband who had spent six years in Israeli prison what life was like there.

Now he knows. The younger Mr. Zawara’a, who left school after 11th grade and worked occasionally harvesting olives or in construction, calls once a day from the jail in Beersheba where he is awaiting trial on Feb. 23 for entering Israel illegally.

“The prison is good, because all of them live in a sense of safety,” said Ms. Zawara’a, who has visited her son twice in jail. “After the war, he got really depressed. He started to feel like there is no life and there is no money, no employment.”

“All the people in this place, in each house, you can find someone who tried to cross,” she added. “When I was traveling in the bus, the Israelis were asking us: ‘What’s wrong? Suddenly, the whole neighborhood is coming to us.’ ”

1741. Reinventing Cuban Culture

By Dariela Aquique, Havana Times, February 18, 2015

Abel Prieto, Special Advisor to Raul Castro. Photo: havanaradio.cu

The other day, I read somewhere that Abel Prieto, President Raul Castro’s advisor and Cuba’s former Minister of Culture, had expressed concerns over what he calls the “Americanization” of culture.

For some time now, Cuban authorities have expressed their preoccupation over how certain sectors of the population, particularly the new generations, are strongly attracted by all things foreign and tend to undervalue local culture.

On the street, we see people wearing T-shirts, caps, belts, kerchiefs and wallets bearing the flags of the United States, Great Britain, Spain, Italy and a whole series of other countries. It is becoming more and more difficult to run into someone wearing something that invokes Cuba as a country.

Young people imitate foreign customs and throw Halloween-styled parties. Girls refer to sleep-overs as “pajama parties” and want to put together cheerleading squads. Teenagers go out to private discos where DJs and electronic music replace casino dancing.

Cuban society is straying from its traditional customs. Boys and girls are given foreign names like Jonathan, Jordan, Christian or Stephanie. In a country with such a limited and restricted access to the Internet, people are increasingly interested in owning sophisticated, cutting-edge wireless technologies – sometimes only to boast about it.

In a country where saving any money is a true ordeal, people are buying expensive pets, throwing ballroom parties for Sweet 15 celebrations and arranging pompous weddings (with a master of ceremonies and all), invoking a “high life” which the revolution was meant to have abolished, a lifestyle that appears to rise from the ashes like the Phoenix.

At home, families prefer to pay for the so-called “weekly package” and watch these shows on their DVDs than to sit through Cuban television programming.

Why is this taking place?

It’s simple, Abel Prieto. This “Americanization” of society or “cult of the foreign”, whatever you want to call it, is the logical response to the many years of politicization of Cuban culture.

What respect towards local culture can one expect from a country that decided to impose Pello el Afrokan on people and forbade them from listening to the Beatles? It’s not that the Afrokan had no merits as a performer, but to deny people the greatest musical phenomenon of the past century was a sacrilege and a blatant show of ignorance.

A lot of literature, cinema and music could not be read, seen or heard in Cuba for decades, only because these were produced by artists who did not support the government or, worse still, because the government didn’t like them. On the other hand, those in line with government policy were promoted, even when they were mediocre artists, as was quite often the case.

Has Abel Prieto forgotten that, in the 70s and 80s, Cuban culture was sovietized? That the T-shirts of the time had photos of Yuri Gagarin or pictures of Misha the Bear? That more than half of the people from my generation are named Alexei, Mikhail, Vladimir, Natasha or Nadia? That I know more than two black men named Volodia?

Yes, it’s true that young people today prefer to wear T-shirts with the shields of Spain’s Barca or Real Madridsoccer teams, or with images of the New York Yankees or St. Louis Cardinals, rather than put on a shirt with an Industriales, Pinar del Rio or Santiago baseball team logo. This is so, first of all, because the former have better designs and are of better quality, and one’s money is better spent on these than on second-rate items sold at hard-currency or peso stores at exorbitant prices.

The communist government senselessly repressed everything it considered a throw-back to bourgeois culture, such as beauty contests (calling these “puerile competitions”), events that were nothing less than social customs in pre-revolutionary Cuba. Cuban women went from wearing cosmetics, putting on fancy clothes and strolling down the cat-walk to heading up mountains to teach people to read and write, going to countryside schools, doing volunteer work and practicing their aim at shooting ranges, to defend the homeland against any aggression by the enemy.

Entire generations grew up surrounded by political slogans and propaganda (present at all sporting, artistic and cultural events), and this has made people reject these almost involuntarily. As Marx said, the law exhausts itself through its compliance, and all things forbidden bid their time, waiting for the moment to resurface. What was forbidden has returned like a boomerang following Cuba’s so-called “social liberalization.”

The worst part is that this wave brings bad things along with the good. People in Cuba may know how to read and write, but their aesthetic education is fairly questionable. That is why a fair number of people opt for the banality of Mexican and Venezuelan soap operas, Colombian TV series, where the main character is always a drug dealer, reality shows, silly game-shows, sensationalist news programs and other demons.

Though we cannot deny that a good part of Cuba’s television programming aims at the didactic and the promotion of the arts, the precarious set-design and lighting and the cursed intrusion of political messages everywhere have made these programs lose much of their audience.

The specter of political subversion and the fear of individual wealth have been the pretexts and reasons invoked to take down highly valuable cultural projects. Let us recall the case of poet Heberto Padilla and his forced confession more than 40 years ago, or, more recently, the closing down of the Pedro Pablo Oliva Visual Arts Workshop – or the shutting down of baritone Ulises Aquino’s restaurant and cultural venue El Cabildo, to name only a few cases.

Cubans face an uncertain future. Social uncertainty and political crisis are translated into the search of an identity that was distorted.

Now the president’s advisor, Abel Prieto, fears the “Americanization” of culture, but, following the Words to Intellectuals, what we had was the “Castroization” of culture. Then came the sovietization of culture. Today, some talented people of good faith are creating art. Others lose themselves in mediocrity and mimicry. Both, in their own way, are reinventing our culture.

1740. Unlocking the Mystery of the First Billion Years of the Universe

By Steven Tingay, The Conversation, February 17, 2015

More than 100 million years has been wiped off the age of the first stars but there is still the question of what happened in the first billion years of the universe.

Earlier this month the European Space Agency’s Planck mission team announced that the first stars formed some 560 million years after the Big Bang.

This is approximately 140 million years later than previously thought. It is an interesting result because it helps us to understand how structures such as stars and galaxies formed and evolved after the Big Bang.

The Planck team were studying the Cosmic Microwave Background (CMB), the radiation left over from the Big Bang, the origin of our universe. The CMB can be traced to events that occurred only approximately 380,000 years after the Big Bang.

Polarisation of the Cosmic Microwave Background across the sky, the latest data from the ESA Planck mission. ESA and the Planck Collaboration, CC BY

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Since the CMB discovery about 50 years ago, astrophysicists have been analysing it to better understand the early evolution of our universe, accurately measure its age (approximately 13.8 billion years) and help us realise that the laws of physics do not properly describe approximately 95% of the universe that we live in.

A short time after the Big Bang, almost all the ordinary matter created took the form of protons and electrons that, after 380,000 years, settled into hydrogen atoms (each atom is one proton and one electron bound together). Hydrogen is the simplest atom possible and the basic building block for everything we humans can see and touch in the universe (ordinary matter).

The Planck result means that over the first 560 million years, under the influence of gravity, this hydrogen gas collapsed into stars.

Inside stars, hydrogen atoms get combined into helium, oxygen, nitrogen, carbon and other elements. These elements end up in new stars, planets, oceans, DNA, iron ore deposits and so on. Quite useful stuff for humans. Stars really are the engines of life.

What happened next?

But we currently know little about what happened after the first stars formed. If we fast forward the universe 500 million years, we know that galaxies were forming, because we can see a few of them, such as UDFy-38135539, at the limits of powerful telescopes such as the Hubble Space Telescope.

If we fast forward again, another few billion years, the universe looks a lot like it does now, 13.8 billion years after the Big Bang.

So how exactly did the universe go from hydrogen, to stars, to galaxies and to life?

A Spitzer Space Telescope image of Messier 81, a spiral galaxy something like what our galaxy, the Milky Way, might look like if seen from the outside. Such a galaxy would contain billions of stars. NASA/JPL-Caltech/S. Willner (Harvard-Smithsonian Center for Astrophysics)

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Planck has narrowed things down for us with an exciting result – no stars before about 560 million years, and the universe is starting to look vaguely familiar roughly 500 million years after that.

But those first billion years remain the last great unexplored period in the evolution of our universe (aside from the future of the universe).

So how do we go about uncovering these mystery years of the early universe? Even powerful telescopes such as Hubble cannot examine the formation of the first stars as they are too distant and faint, and stars do not produce visible light until they turn on.

Radio astronomy holds the key to the early universe

Happily, astronomers have a different and powerful set of tools to crack this nut. Atoms of hydrogen emit radio waves with a specific wavelength of 21cm (similar wavelength to what your mobile phone uses).

The hydrogen formed in the early universe produced these radio waves. By the time the radio waves travel all the way to us on Earth, through an expanding universe, they change their wavelength from 21cm to several metres (similar wavelength to what your FM radio uses).

If we can “tune in” to the radio waves, we can watch what the hydrogen gas is doing in the early universe, 100 million, 200 million, 500 million or a billion years after the Big Bang.

We can watch how the hydrogen gas forms into stars, how the stars are distributed, how long they take to form, how much energy they produce, and how galaxies start to form.

As the stars turn on, their radiation breaks apart the surrounding hydrogen atoms, leaving a “Swiss cheese” pattern (see below) in the radio emitting gas for astronomers to detect and analyse.

The Big Bang is at the left of this diagram. We live in a galaxy at the right of the diagram, 13.8 billion years after the Big Bang. NASA/CXC/SAO

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Facilities in Australia are at the forefront

This is a challenge that astronomers are now embracing, by building massive telescopes capable of collecting these radio waves, such as the Murchison Widefield Array (MWA).

The MWA is located in the middle of Murchison Shire in Western Australia, well away from sources of human-made radio wave interference (mobile phones, microwave ovens, FM radio stations and cars) where we can pick up these faint radio whispers from the early universe.

Over the past two years, we have used the MWA to collect 4 petabytes of data (the equivalent of over 5,700 hours of full HD video) and have produced more than 50 scientific papers from the data already.

Part of the Murchison Widefield Array radio telescope, Western Australia. Curtin University

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Our data are stored at the Pawsey supercomputer centre in Perth and we are sifting carefully through them using millions of supercomputer hours to obtain the first hints of the formation of the first stars and galaxies.

Competition to make the first detection of these radio signals comes from other telescopes in the US, The Netherlands and South Africa. So unlocking the mysteries of the first billion years of the universe is a big scientific prize.

But the MWA is only the first step needed to fill the gaps that Planck has so elegantly defined. A much larger radio telescope is needed, and that’s where the Square Kilometre Array (SKA) comes in.

The MWA is a A$50-million science and engineering precursor for the SKA, specifically the low frequency SKA, which will be approximately 100 times bigger than the MWA.

The SKA, when it’s switched on sometime in the next decade, will fill in the first billion year gap in detail and help us understand how the universe transformed from hydrogen gas into us. The MWA is designed to light the trail for the SKA.

Part of what the low frequency SKA may look like in the future. Hundreds of thousands of simple low frequency antennas spread over 10s of kilometres of the Western Australian outback.SKA/Curtin University/LFAA consortium/Swinburne University of Technology

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The great news for Australia is that this much bigger SKA facility will be built on the same site as the MWA, in Western Australia, learning from our solid and hard won experience, placing Australian science and engineering on page one of the next exciting multi-decade chapter in the unfolding story of cosmic discovery

Steven Tingay is professor of Radio Astronomy at Curtin University, Australia.

1739. Americans Are Heading to Cuba for Medical Tourism

By William Neuman, The New York Times, February 17, 2015

Institute of Cardiology and Cardiovascular Surgery, Havana, Cuba

HAVANA — Anuja Agrawal jumped on the phone. President Obama had just announced that he would restore diplomatic relations with Cuba — and Ms. Agrawal, who runs a medical tourism company in Orlando, Fla., did not want to miss her opening.

She reached a health care administrator in Cuba, agreeing to move ahead with a deal that they had been discussing for months in the hope that American patients could soon start traveling to the island for medical treatment.

“There was a lot of excitement about it,” said Ms. Agrawal, the chief executive of Health Flights Solutions, adding that if Americans start traveling to Cuba for affordable medical treatments, it could mean a big economic boost for the country’s health system. “For them, they’re looking at it literally like winning the lottery.”

As the Obama administration chips away at the economic isolation of Cuba, whittling at an embargo that is older than most people on this island, industries of many kinds are trying to figure out what the easing of tension will mean for them, and exactly how much wiggle room there will be.

Thousands of people from other countries go to Cuba each year for what is known as medical tourism: travel abroad for surgery or other medical care, often because the treatment is less expensive there or is not available where patients live.

Now, the Obama administration has relaxed restrictions on travel to Cuba. Americans can come here for a range of reasons, including family visits, academic conferences, public performances, and religious and educational activities. While tourism or traveling to receive health care are still not allowed, the administration lifted a restriction requiring many Americans to travel with authorized groups or get a license in advance to visit the island.

“It’s a relaxation, a loosening of the restrictions,” Ms. Agrawal said, adding that once the door is open, “I always think it’s going to get looser and looser.”

In practice, the changes could mean that many more people will feel free to travel to Cuba, even for purposes outside the allowed categories. Thousands of Americans already travel to Cuba for tourism or other reasons that fall outside the guidelines, and even before the changes, many Cuban-Americans visiting family would take the opportunity to schedule medical treatments, many people here said.

A Treasury Department spokeswoman said that Americans wishing to travel to Cuba for reasons that fell outside the authorized activities could apply for permission, known as a special license, and that such requests would be evaluated on a case-by-case basis.

But the spokeswoman, who said she was authorized to speak only on background, said that Americans traveling to Cuba were required to keep records of their trip for five years and could be subject to audits to show that their travel met the guidelines.

Jonathan Edelheit, the chief executive of the Florida-based Medical Tourism Association, said some hospitals in the United States had expressed interest in forming partnerships with Cuban medical institutions, which could include the training of Cuban doctors. Such partnerships in other countries often go hand in hand with medical tourism, and that could eventually be the case in Cuba, he said.

“You’re going to see a tremendous amount of movement, whether it’s travel agents or medical tourism facilitators, so once it does normalize, they can start sending patients over there,” Mr. Edelheit said.

Cuba made health care a priority after its 1959 revolution, and it has earned a reputation for providing good, mostly free care to its people. Thousands of Cuban doctors also work abroad, in Venezuela, Brazil and other developing countries, in an exchange that provides the government of President Raúl Castro with hard currency or goods, such as oil, in return.

Mr. Edelheit said Cuban health care would be likely to appeal to some Americans because the island is so close, about an hour’s flight from Miami to Havana.

But for now, the most popular destinations for Americans who travel abroad for health care are Canada, the United Kingdom, Israel, Singapore and Costa Rica, according to a study by the Medical Tourism Association. It found that some of the most common procedures included spinal, weight-loss and cosmetic surgery, and cancer treatment.

Ms. Agrawal said she had been speaking to a Cuban health care facility for months, anticipating an eventual opening between the two countries.

“In terms of being a viable destination, what was holding it back, of course, was the travel restrictions and embargo,” she said of Cuba. “Now, with some of that opening up, they’ve got extremely good health care. They’re very close in terms of travel.”

Unlike Americans, Canadians do not have travel restrictions, and Cuba is a popular vacation destination; many Canadians travel there for health care as well.

David McBain, 47, a Toronto landscaper who fractured his spine in a car accident, went to Cuba three times last year for extensive physical therapy.

“The physiotherapists and the doctors are extremely knowledgeable and well trained in Cuba, and you just can’t beat the price,” Mr. McBain said. “The price is a fraction of what it would be in Canada or the U.S. for a therapist.”

Mr. McBain, who is partly paralyzed and uses a wheelchair, said he was treated for several weeks during each visit at a Havana facility. He said the treatment in Cuba cost about $200 a day, which includes about six hours of physical therapy daily, a comfortable room and board. Canada’s national health system does not provide for the type of therapy he needs, he said, and a private neurological physical therapist would charge about $93 an hour.

Mr. McBain arranged for his care in Cuba through a Toronto company called Global HealthQuest. Ben Soave and Rosemary Toscani, who run the company, said they regularly sent patients to Cuba for physical therapy, drug and alcohol rehabilitation, and for treatment of an eye disease called retinitis pigmentosa.

The eye surgery and related treatments, pioneered at a Cuban clinic, are not available in Canada or the United States, and they have stirred controversy. Independent studies have raised questions about the effectiveness of the treatments, and doctors at the clinic have been criticized for not publishing the results of studies in peer-reviewed medical journals.

“If you’re not presenting your results and publishing, then there’s something not right,” said Dr. Byron L. Lam, a specialist in the disease at the Bascom Palmer Eye Institute in Miami.

Mr. Soave said patients gave good reviews of the care they received in Cuba, although they sometimes complained about other aspects.

“There’s other things that are not so great, like the food, the accommodations, the lack of some of the things we consider basic services, like the Internet, the phones, that sort of thing,” he said. “In terms of medical care, it has been excellent.”

He also said the patients he had worked with did not seek out treatment in Cuba because they had political sympathies with its socialist government.

“We have people asking, ‘Where can we go to get the best care?’ ” Mr. Soave said. “They’re thinking health, not politics.”

While Cuba is well known for its government-run health care, the system also struggles with problems. Doctor appointments and hospital stays are free, but most patients must pay for their own medicines, which can be difficult on the island’s typically low salaries.

Some medicines are hard to find or unavailable, and hospitals may lack up-to-date equipment, although doctors said the government had recently been investing in modernizing some facilities. Health care workers also received a significant salary increase last year, with some of the higher-paid doctors seeing their monthly wages rise to $67 from $26.

Gail Reed, an American who edits a medical journal here in Havana, said she hoped that additional income from Americans traveling to Cuba for medical care would be invested back into the Cuban health care system.

“Any injection of real, new sources of funding into the health system would be a boon to Cuba and Cubans,” Ms. Reed said.

1738. A Biofuel Debate: Will Cutting Trees Cut Carbon?

By Eduardo Porter, The New York Times, February 10, 2015

Does combating climate change require burning the world’s forests and crops for fuel?

It certainly looks that way, judging from the aggressive mandates governments around the globe have set to incorporate bioenergy into their transportation fuels in the hope of limiting the world’s overwhelming dependence on gasoline and diesel to move people and goods.

While biofuels account for only about 2.5 percent today, the European Union expects renewable energy — mostly biofuels — to account for 10 percent of its transportation fuel by 2020. In the United States, the biofuel goal is about 12 percent by early in the next decade. The International Energy Agency envisions using biofuels to supply as much of 27 percent of the world’s transportation needs by midcentury.

The reasons for such ambitions are clear: It is nearly impossible under current technology to run cars, trucks, ships and jet planes on energy generated from wind or sun.

There is a big problem with this strategy, though. An economist would say that it ignores the “opportunity costs” of deploying vegetation as a source of energy. Others call it double counting.

“Dedicating land to bioenergy always comes at a cost because that land cannot produce plants for other purposes,” said Timothy Searchinger, a researcher at Princeton and the World Resources Institute and a co-writer of a recent report that calls for a rollback of crops dedicated to biofuels.

In a nutshell, says Mr. Searchinger, the energy from forests and fields is not, in fact, carbon-free.

The argument for aggressive deployment of bioenergy assumes that it is carbon-neutral because plants pull CO₂ back from the air when they grow, offsetting the carbon emitted from burning them as fuel. But diverting a cornfield or a forest to produce energy requires not using it to make food or, just as important, to store carbon.

“Burning biomass instead of fossil fuels does not reduce the carbon emitted by power plants,” a group of 78 scientists wrote on Monday to Gina McCarthy, the E.P.A.’s director, warning against the new power plant policy. “Burning biomass, such as trees, that would otherwise continue to absorb and store carbon comes at the expense of reduced carbon storage.”

If the critics are right, the hunt for biomass on a large scale could vastly change the world’s land use, food supply and ecosystems while helping little to prevent climate change.

The argument for caution has so far mostly fallen on deaf ears. The reason is that policy makers see little choice.

Last year, the Intergovernmental Panel on Climate Change rendered its latest assessment of scientists’ collective understanding of how to slow the pace of global warming. Riddled with the usual uncertainties of science, it seemed pretty certain of one thing: Doing it without biofuels would be much harder.

Absent a big increase in bioenergy supplies, the climate change panel’s analysis reported, it would cost about two-thirds more, on average, to prevent the earth’s temperature from rising more than 2 degrees Celsius above preindustrial levels, generally considered the tipping point for climatic upheaval.

The availability of biofuels makes more difference to the ultimate price tag, the panel concluded, than whether electricity generation can be harnessed successfully to the sun and wind. Only carbon capture and storage technology is more important.

In most of the climate change panel’s models that bring temperatures back under the 2-degree ceiling by the end of the century, biofuels are assumed to produce about 250 to 350 exajoules of energy a year.

To put that in context, 300 exajoules is over half the world’s current energy consumption. Today, the energy content of all the biomass harvested for food, fodder and everything else amounts to about 220 exajoules.

The question is, Where will the land to produce all this additional vegetation come from?

As a committee of the European Environmental Agency noted, to reduce the amount of CO₂ in the air, bioenergy production “must increase the total amount of plant growth, making more plants available for energy use while preserving other benefits.”

André Faaij, an expert on energy systems at the University of Groningen in the Netherlands and author of many important assessments used by the panel on the potential for bioenergy, argues that it is definitely feasible.

The world could feed 35 billion people (the earth’s current population is seven billion) if only the productivity of agriculture and livestock in the developing world were brought to developed country standards, he said. “Mozambique could feed all of Africa if it just increased its productivity to that of the Netherlands.”

That could free up a lot of land. Deploying just 10 percent of the world’s five billion hectares currently used for crops and pastures to grow biofuels could generate 100 to 150 exajoules by the end of the century. An additional 60 to 70 could be had from planting biofuels on currently degraded land. The rest could come from better harvesting of forests and the use of organic waste.

In a recent research article, Professor Faaij and colleagues calculated that it would be technically possible to get about 100 exajoules by 2050 from what they call “surplus forest growth,” meaning the bits of forest that are neither protected nor already exploited for wood, and wood waste.

This sort of calculation drives Mr. Searchinger up the wall. “Surplus forest growth” he said, is already pulling CO₂ from the air. Harvesting it for energy will provide no further benefit for climate change. The same could be said of idled agricultural land, where forest usually starts regrowing soon, capturing carbon from the air.

“In many contexts, allowing a forest to grow will do more to reduce carbon dioxide in the atmosphere for decades than producing bioenergy,” he told me.

And he finds the estimates of future agricultural productivity unbelievable when applied to any reasonable understanding of the real world. Indeed, it will be hard to maintain the productivity growth of the last several decades, he says, let alone substantially increase it.

“Because the world needs to produce 70 percent more of virtually all the products of land — crops, grasses and wood — by 2050, there is no additional room for bioenergy, and any capacity to increase crop yields and to make better use of any underutilized land is already needed for these other purposes,” Mr. Searchinger said.

Professor Faaij says the skeptics are wrong, arguing that the alternatives to a huge increase in biofuel production would be even more difficult to achieve.

But it could be possible to produce the zero-carbon energy the world will need without incurring such steep opportunity costs. Much of the transport fleet could be electrified, reducing demand for liquid fuels. Solar power could be used to produce hydrogen to burn in fuel cells.

There is probably a limited role for biofuels from waste products. But the biofuels juggernaut — which has helped garner the support of agribusiness in the battle against climate change — could end up doing more harm than good.

The United States used to rely heavily on bioenergy for transport: 100 years ago, tens of millions of acres were devoted to growing feed for pack animals. Since then, much of this land has reverted to forest. Razing it again for fuel is not the best idea.