Environment – Page 4 – The Progressive Democrat

Hummingbirds: hovering on the brink of extinction

I have been fascinated by hummingbirds ever since I was given a pack of wild animal cards in hospital while my tonsils were removed and fell in love with Heliothrix aurita, a speck of fire and jade. And also wine-red Topaza pella, perched in a jungle whisking a crimson tail.

I still have those cards. Their pictures seem crude now, but when I was eight I was enraptured. The Aztecs said the Earth’s first flower was fathered by the god of poetry in the shape of a hummingbird; and everything about hummingbirds seems tailor-made for a poet.

Birds see ultraviolet light, and female hummingbirds have a taste for iridescence, so males have turned themselves into flying jewels. Their metallic sheens, glancing as soap bubbles, are reflected in equally iridescent names for which taxonomists have plundered all the shimmer in the lexicon.

There are more than 300 species: words such as emerald, copper, bronze, gold, fire, sapphire, lazuline, emerald and sunbeam spill like Aladdin’s treasure through the list: amethyst woodstar, blue-headed sapphire, Brazilian ruby, buff-winged starfrontlet – you marvel not only at nature’s capacity for spangly variation but the human urge to match it in language.

Hummingbird nests – the size of a nutshell, spun out of plant down, covered with lichen, bound by spider’s silk – are works of art straight out of A Midsummer Night’s Dream. Hummingbird tongues, almost transparent, are liquid-trapping miracles of bioengineering that change shape as they flick in and out of the nectar. Their tips are forked: the V’s inside edges have feathery tufts that draw in nectar by capillary action. When hummingbirds sleep they fall into hibernation-like torpor. Metabolism drops, temperature zooms to near-hypothermic levels and breathing slows so drastically that if you find a sleeping hummingbird you think it’s dead. Which, in the Peruvian Andes, makes it a symbol of resurrection.

Monarch butterfly numbers drop to new lows

Few monarchs in eastern Canada this year

The number of monarch butterflies now on their migration to Mexico appear to to be at record lows. A monarch feeds on silky red milkweed, in a monarch way station as part of Monarch Watch, a continental effort to create backyard habitats for the butterflies along their migratory routes. (Steve Smedley/The Pantagraph/Associated Press)

Monarch butterflies appear headed for a perhaps unprecedented population crash, according to scientists and monarch watchers who have been keeping tabs on the species in their main summer home in Eastern and Central North America.

There had been hope that on their journey north from their overwintering zone in Mexico, the insects’ numbers would build through the generations, but there’s no indication that happened.

Only a small number of monarchs did make it to Canada this summer to propagate the generation that has now begun its southern migration to Mexico, and early indications are that the past year’s record lows will be followed by even lower numbers this fall.

Elizabeth Howard, the director and founder of Journey North, a citizen-scientist effort that tracks the migrations of monarchs and other species, says one indicator for the robustness of the monarchs is the number of roosts they form in late August and September, something Journey North monitors throughout the migration periods.

Overpopulation Is Still the Problem | Alon Tal

Overpopulation remains the leading driver of hunger, desertification, species depletion and a range of social maladies across the planet. Recently, a spate of op-ed essays have filled the pages of some of world’s top newspapers and blogs — from the Guardian to the New York Times — challenged this view, declaring that overpopulations is not, nor has ever been, a problem. To make progress in the most recent round of the age-old debate between technological optimists and Malthusian realists, it’s important to establish criteria and characterize consequences.

On what basis are these newest cornucopian assurances made? In the New York Times piece, for instance, Ellis Erle asserts that after studying the ecology of agriculture in China and talking to archaeologists, he reached the conclusion that technologies have always been able to overcome any anticipated exceedance of carrying capacity. A key corroboration marshaled for this view refers to a retrospective assessment of Chinese farming by archaeologists. It purportedly claims that new and more efficient technologies invariably enabled local farmers to overcome any anticipated exceedance of carrying capacity.

On what basis are these newest cornucopian assurances made? In the New York Times piece, for instance, Ellis Erle asserts that after studying the ecology of agriculture in China and talking to archaeologists, he reached the conclusion that technologies have always been able to overcome any anticipated exceedance of carrying capacity. A key corroboration marshaled for this view refers to a retrospective assessment of Chinese farming by archaeologists. It purportedly claims that new and more efficient technologies invariably enabled local farmers to overcome any anticipated exceedance of carrying capacity.

Conservative estimates report that China’s most recent food crisis, between 1958 and 1961, led to the starvation of over twenty million people, in part due to the erosion of China’s natural capital. Uncontrolled human fertility led to a depletion of the land’s fertility. Previous famines were worse. Over the years, hundreds of millions died a horrible death of hunger. Their misery should teach a sobering lesson about insouciant disregard for the balance between human numbers and natural resources.

Conservative estimates report that China’s most recent food crisis, between 1958 and 1961, led to the starvation of over twenty million people, in part due to the erosion of China’s natural capital. Uncontrolled human fertility led to a depletion of the land’s fertility. Previous famines were worse. Over the years, hundreds of millions died a horrible death of hunger. Their misery should teach a sobering lesson about insouciant disregard for the balance between human numbers and natural resources.

Overpopulation: Why ingenuity alone won’t save us – latimes.com

We are running out of tricks to squeeze more from a planet already bursting its seams.

Children at Dadaab receive a supplemental meal in an effort to give them caloric intake they need to grow and survive. (Los Angeles Times)

It’s easy to grasp that in a national park, balance must be maintained between predators and prey, lest the ecosystem crash. But when we’re talking about our own species, it gets harder. The notion that there are limits to how much humanity this parkland called Earth can bear doesn’t sit easy with us.

The “nature” part of human nature includes making more copies of ourselves, to ensure our genetic and cultural survival. As that instinct comes in handy for building mighty nations and dominant religions, we’ve set about filling the Earth, rarely worrying that it might one day overfill. Even after population quadrupled in the 20th century, placing unprecedented stress on the planet, it’s hard for some to accept that there might be too many of us for our own good.

A recent essay in the New York Times by University of Maryland geographer Erle C. Ellis, argued that population growth is actually the mother of invention, that it inspires new technologies to sustain ever more humans and to coax more from the land. And as Pope Benedict XVI wrote in his 2009 encyclical “Caritas in Veritate,” “On this Earth there is room for everyone … through hard work and creativity.”

In 2011, I visited the Vatican’s Pontifical Academy of Sciences, which had warned in 1994 that it was “unthinkable to sustain indefinitely a birthrate beyond 2.3 children per couple…. The contrary demographic consequences would be unsustainable to the point of absurdity.” Nevertheless, the church still encouraged population growth.

With a billion humans already malnourished, I asked the academy’s director where would we get food for nearly 10 billion by midcentury? Clearing more forests for farming would be disastrous. Beset by floods and erosion, China alone has been spending $40 billion to put trees back. And force-feeding crops with chemistry has backfired on us, with nitrogen runoff that fouls rivers, deadens New Jersey-sized chunks of the oceans and emits large quantities of two greenhouse gases: carbon dioxide and nitrous oxide.

The answer, I was told, would be through increased yields using new genetically modified crops from the centers of the Green Revolution: the International Maize and Wheat Improvement Center in Texcoco, Mexico, and the International Rice Research Institute in the Philippines.

The Green Revolution’s high-yield, genetically selected strains more than doubled grain harvests during the 1960s. It is often cited as having triumphed over dire predictions of famines caused by population growth outpacing food production, which were famously made by economist Thomas Robert Malthus in “An Essay on the Principle of Population” and echoed by his latter-day analogues, Paul and Anne Ehrlich, who wrote “The Population Bomb.”

However, when I went to the maize center in Texcoco and to the rice institute in the Philippines, I found no food scientists who agreed with that triumphalist scenario. Instead, I learned, Green Revolution founder Norman Borlaug had warned in his 1970 Nobel Peace Prize acceptance speech that his work essentially had only bought the world time to resolve overpopulation.

Alan Weisman: Just by existing, we’re contributing to the problem – Salon.com

The only way we can keep living on Earth, the author writes in his new book, is if there are fewer of us

In his 2007 book “The World Without Us,” Alan Weisman took on an ambitious thought experiment: What if mankind were to suddenly disappear from the planet? It was an apocalyptic scenario, to be sure, but it arguably pales in comparison to the alternative: What if, instead of going anywhere, we just keep making more of ourselves?

“Countdown,” which hits shelves today, takes on that scenario, as a reality that’s quickly approaching. This time, the question for Weisman isn’t just about what could happen — it’s about what we could possibly do to prevent it.

Technology isn’t going to fix this problem, Weisman found. And though the book’s subtitle is phrased as a question (“Our Last, Best Hope for a Future on Earth?”) the answer is clear: If we want to keep going, he argues, there needs to be fewer of us. Weisman spoke with Salon about our cross-cultural impulse to be fruitful and multiply, and his quest to find a more sustainable mantra for humanity. This interview has been lightly edited for length and clarity.

Timing a Rise in Sea Level

The fast-retreating Sheldon Glacier in Antarctica. A collapse of a polar ice sheet could result in a jump in sea level.

Thirty-five years ago, a scientist named John H. Mercer issued a warning. By then it was already becoming clear that human emissions would warm the earth, and Dr. Mercer had begun thinking deeply about the consequences.

His paper, in the journal Nature, was titled “West Antarctic Ice Sheet and CO2 Greenhouse Effect: A Threat of Disaster.” In it, Dr. Mercer pointed out the unusual topography of the ice sheet sitting over the western part of Antarctica. Much of it is below sea level, in a sort of bowl, and he said that a climatic warming could cause the whole thing to degrade rapidly on a geologic time scale, leading to a possible rise in sea level of 16 feet.

While it is clear by now that we are in the early stages of what is likely to be a substantial rise in sea level, we still do not know if Dr. Mercer was right about a dangerous instability that could cause that rise to happen rapidly, in geologic time. We may be getting closer to figuring that out.

An intriguing new paper comes from Michael J. O’Leary of Curtin University in Australia and five colleagues scattered around the world. Dr. O’Leary has spent more than a decade exploring the remote western coast of Australia, considered one of the best places in the world to study sea levels of the past.

The paper, published July 28 in Nature Geoscience, focuses on a warm period in the earth’s history that preceded the most recent ice age. In that epoch, sometimes called the Eemian, the planetary temperature was similar to levels we may see in coming decades as a result of human emissions, so it is considered a possible indicator of things to come.

Examining elevated fossil beaches and coral reefs along more than a thousand miles of coast, Dr. O’Leary’s group confirmed something we pretty much already knew. In the warmer world of the Eemian, sea level stabilized for several thousand years at about 10 to 12 feet above modern sea level.

The interesting part is what happened after that. Dr. O’Leary’s group found what they consider to be compelling evidence that near the end of the Eemian, sea level jumped by another 17 feet or so, to settle at close to 30 feet above the modern level, before beginning to fall as the ice age set in.

In an interview, Dr. O’Leary told me he was confident that the 17-foot jump happened in less than a thousand years — how much less, he cannot be sure.

This finding is something of a vindication for one member of the team, a North Carolina field geologist, Paul J. Hearty. He had argued for decades that the rock record suggested a jump of this sort, but only recently have measurement and modeling techniques reached the level of precision needed to nail the case.

5 Terrifying Statements in the Leaked Climate Report | Mother Jones

In the long run, global sea level rise could easily exceed 5 meters. Brendan Howard/Shutterstock

Climate Desk has obtained a leaked copy of the draft Intergovernmental Panel on Climate Change’s 2013 Summary for Policymakers report, which other media outlets are also reporting on. The document is dated June 7, 2013. We recognize, as we’ve previously reported, that this document is not final, and is in fact certain to change.

Most media outlets are focusing on the document’s conclusion that it is now “extremely likely”—or, 95 percent certain—that humans are behind much of the global warming seen over the last six decades. But there is much more of note about the document—for instance, the way it doesn’t hold back. It says, very bluntly, just how bad global warming is going to be. It gives a sense of irreversibility, of scale…and, of direness.

In particular, here are five “holy crap” statements from the new draft report:

We’re on course to change the planet in a way “unprecedented in hundreds to thousands of years.” This is a general statement in the draft report about the consequences of continued greenhouse gas emissions “at or above current rates.” Unprecedented changes will sweep across planetary systems, ranging from sea level to the acidification of the ocean.