Humanity is ‘cutting down the tree of life’, warn scientists

The Guardian reports:

Humanity’s ongoing annihilation of wildlife is cutting down the tree of life, including the branch we are sitting on, according to a stark new analysis.

More than 300 different mammal species have been eradicated by human activities. The new research calculates the total unique evolutionary history that has been lost as a result at a startling 2.5bn years.

Furthermore, even if the destruction of wild areas, poaching and pollution were ended within 50 years and extinction rates fell back to natural levels, it would still take 5-7 million years for the natural world to recover.

Many scientists think a sixth mass extinction of life on Earth has begun, propelled by human destruction of wildlife, and 83% of wild mammals have already gone. The new work puts this in the context of the evolution and extinction of species that occurred for billions of years before modern humans arrived.

“We are doing something that will last millions of years beyond us,” said Matt Davis at Aarhus University in Denmark, who led the new research. “It shows the severity of what we are in right now. We’re entering what could be an extinction on the scale of what killed the dinosaurs.

“That is pretty scary. We are starting to cut down the whole tree [of life], including the branch we are sitting on right now.” Ecosystems around the world have already been significantly affected by the extermination of big animals such as mammoths, he said. [Continue reading…]

Limiting global warming to 1.5°C will require deep emissions cuts

Climate Central reports:

The Paris Climate Change Agreement set a goal of “holding the increase in the global average temperature to well below 2°C (3.6°F) above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C (2.7°F).” In that agreement, world leaders asked the IPCC, the preeminent climate science body, “to provide a Special Report in 2018 on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways.” After being formally approved by all the UN country representatives, that special report was released this week.

Human activities have already warmed the planet about 1°C (1.8°F) since the pre-industrial era, defined by the IPCC as the latter half of the 19th century. At the current rate of warming, Earth would reach the 1.5°C threshold between 2030 and 2052. Limiting warming to 1.5°C is not easy and requires drastic changes to our energy, transportation, food, and building systems. Net CO2 emissions need to drop 45 percent from their 2010 levels by 2030, and reach net-zero by 2050 (meaning that any remaining CO2 emissions would need to be offset by removing carbon dioxide from the atmosphere).

Meeting this goal involves a large jump in renewables for the global energy supply, providing 70-85 percent of electricity use by 2050. Moreover, because CO2 remains in the atmosphere for centuries, we have already committed to future warming with our historical emissions. As a result, even with drastic emissions cuts, meeting this 1.5°C goal likely means a brief exceedance, or overshoot, of the 1.5°C threshold before returning to that level for the longer term and requires some removal of CO2 from the atmosphere — either via reforestation, soil carbon sequestration, or technological advancements enabling direct capture of carbon from the atmosphere. [Continue reading…]

A growing wave of extinctions is sweeping across the continents

The Guardian reports:

Spix’s macaw, a brilliant blue species of Brazilian parrot that starred in the children’s animation Rio, has become extinct this century, according to a new assessment of endangered birds.

The macaw is one of eight species, including the poo-uli, the Pernambuco pygmy-owl and the cryptic treehunter, that can be added to the growing list of confirmed or highly likely extinctions, according to a new statistical analysis by BirdLife International.

Historically, most bird extinctions have been small-island species vulnerable to hunting or invasive species but five of these new extinctions have occurred in South America and are attributed by scientists to deforestation.

Stuart Butchart, BirdLife International’s chief scientist, said the new study highlighted that an extinction crisis was now unfolding on large continents, driven by human habitat destruction.

“People think of extinctions and think of the dodo but our analysis shows that extinctions are continuing and accelerating today,” he said. “Historically 90% of bird extinctions have been small populations on remote islands. Our evidence shows there is a growing wave of extinctions washing over the continent driven by habitat loss from unsustainable agriculture, drainage and logging.”

More than 26,000 of the world’s species are now threatened, according to the latest “red list” assessment, with scientists warning that humans are driving a sixth great extinction event. [Continue reading…]

Wildlife preservation depends on saving animals, their habitats, and their cultures

Ed Yong writes:

In the 1800s, there were so many bighorn sheep in Wyoming that when one trapper passed through Jackson Hole, he described “over a thousand sheep in the cliffs above our campsite.” No such sights exist today. The bighorns slowly fell to hunters’ rifles, and to diseases spread from domestic sheep. Most herds were wiped out, and by 1900, a species that once numbered in the millions stood instead in the low thousands.

In the 1940s, the Wyoming Game and Fish Department began trying to move bighorns back into their historic habitats. Those relocations continue today, and they’ve been increasingly successful at restoring the extirpated herds. But the lost animals aren’t just lost bodies. Their knowledge also died with them—and that is not easily replaced.

Bighorn sheep, for example, migrate. They’ll climb for dozens of miles over mountainous terrain in the spring, “surfing” the green waves of newly emerged plants. They learn the best routes from one another, over decades and generations. And for that reason, a bighorn sheep that’s released into unfamiliar terrain is an ecological noob. It’s not the same as an individual that lived in that place its whole life and was led through it by a knowledgeable mother.

“The translocated animals were literally let out of a livestock trailer and started looking around at their new environment,” says Matthew Kauffman from the University of Wyoming. “And they almost entirely failed to migrate.”

Kauffman knows this because the translocated sheep were often fitted with radio collars, allowing him and his colleagues to compare their movements to those of bighorns that lived in the same place for centuries. Within those longstanding herds, between 65 and 100 percent of the sheep migrated. But in the translocated herds, fewer than 9 percent migrated—only the sheep that had been moved into established populations that already knew the land. [Continue reading…]

Mollie Tibbetts’ father: Don’t distort her death to advance the racism she opposed

Rob Tibbetts writes:

As I write this, I am watching Sen. John McCain lie in state in the Capitol Rotunda and know that evil will succeed only if good people do nothing. Both Mollie and Senator McCain were good people. I know that both would stand up now and do something.

The person who is accused of taking Mollie’s life is no more a reflection of the Hispanic community as white supremacists are of all white people. To suggest otherwise is a lie. Justice in my America is blind. This person will receive a fair trial, as it should be. If convicted, he will face the consequences society has set. Beyond that, he deserves no more attention.

To the Hispanic community, my family stands with you and offers its heartfelt apology. That you’ve been beset by the circumstances of Mollie’s death is wrong. We treasure the contribution you bring to the American tapestry in all its color and melody. And yes, we love your food.

My stepdaughter, whom Mollie loved so dearly, is Latina. Her sons — Mollie’s cherished nephews and my grandchildren — are Latino. That means I am Hispanic. I am African. I am Asian. I am European. My blood runs from every corner of the Earth because I am American. As an American, I have one tenet: to respect every citizen of the world and actively engage in the ongoing pursuit to form a more perfect union.

Given that, to knowingly foment discord among races is a disgrace to our flag. It incites fear in innocent communities and lends legitimacy to the darkest, most hate-filled corners of the American soul. It is the opposite of leadership. It is the opposite of humanity. It is heartless. It is despicable. It is shameful. [Continue reading…]

Courageous grassroots leaders provide the best hope to a troubled world

Zeid Ra’ad Al Hussein, the UN High Commissioner for Human Rights, who steps down tomorrow, writes:

Across the world, in both the northern and southern hemispheres, there are politicians who are too self-serving, or too spiteful, to care for and protect the most vulnerable. They are not just cowardly but profoundly foolish, because in producing these stress fractures [– the result of decades of mediocre leadership –], they place at risk not only their own futures, but everyone else’s as well.

If we do not change course quickly, we will inevitably encounter an incident where that first domino is tipped—triggering a sequence of unstoppable events that will mark the end of our time on this tiny planet.

Can we swerve in time?

My hope lies in a set of people not widely known internationally, but familiar to those in the human rights community. Unlike the self-promoters—the elected xenophobes and charlatans—these people do have courage. They have no state power to hide behind: instead, they step forward. They are the leaders of communities and social movements, big and small, who are willing to forfeit everything—including their lives—in defence of human rights. Their valour is unalloyed; it is selfless. There is no discretion or weakness here. They represent the best of us, and I have had the privilege of knowing some of them personally, while others are well known to my office.

This is what true leaders look like. Bertha Zuniga Caceres from Honduras, the young daughter of the murdered environmental activist, Bertha Caceres, who has bravely continued her mother’s struggle. Dr Sima Samar in Afghanistan, who leads the country’s independent human rights commission and is utterly fearless, even when threats to her personal safety abound. The same could be said of Senator Leila de Lima in the Philippines, who has now been arbitrarily imprisoned without trial for 18 months. Pierre Claver Mbonimpa from Burundi, a gentle yet principled soul, undeterred even after his son was murdered and he himself survived repeated attacks.

I have also been deeply impressed by the dignity and courage of Denis Mukwege from the Democratic Republic of Congo, an extraordinary human being by any measure. Likewise, I have been humbled by the determination of Angkhana Neelapaijit from Thailand, whose husband, a lawyer, disappeared in 2004 leaving her to become a most courageous activist, fighting against enforced disappearances.

There are others too, from Bahrain for example: the Khawaja family, Nabeel Rajab, Maytham Al Salman and Ebtisam Al Sayegh, who have all have shown extraordinary courage in the face of considerable adversity. Hatoon Ajwad Al Fassi and Samar Badawi in Saudi Arabia: courageous leading voices for the rights of Saudi women, both currently in detention. Amal Fathy in Egypt and Radhya Al Mutawakel in Yemen are also two brave individuals who have put their own safety at risk as they have spoken out against injustice and on behalf of victims of human-rights violations.

Likewise, Ludmila Popovici, an activist against torture in Moldova. In Poland, Barbara Nowacka has been active in organising protests against measures to pull back women’s rights. Sonia Viveros Padilla in Ecuador is fighting for the rights of people of African descent. Close by, in El Salvador, Karla Avelar, the courageous transgender activist, deserves high praise—as does the Peruvian Maxima Acuna, a well-known environmental human rights defender.

I could continue. There are grassroots leaders of movements against discrimination and inequalities in every region. These names are just a sample of the real store of moral courage and leadership that exists among us today. [Continue reading…]

Climate change will make hundreds of millions more people suffer from nutritional deficiencies

The Guardian reports:

Rising levels of carbon dioxide could make crops less nutritious and damage the health of hundreds of millions of people, research has revealed, with those living in some of the world’s poorest regions likely to be hardest hit.

Previous research has shown that many food crops become less nutritious when grown under the CO2 levels expected by 2050, with reductions of protein, iron and zinc estimated at 3–17%.

Now experts say such changes could mean that by the middle of the century about 175 million more people develop a zinc deficiency, while 122 million people who are not currently protein deficient could become so.

In addition, about 1.4 billion women of childbearing age and infants under five years old will be living in regions where there will be the highest risk of iron deficiency. [Continue reading…]

The human domination of the face of the Earth

By Rhett A. Butler

Despite ongoing deforestation, fires, drought-induced die-offs, and insect outbreaks, the world’s tree cover actually increased by 2.24 million square kilometers — an area the size of Texas and Alaska combined — over the past 35 years, finds a paper published in the journal Nature. But the research also confirms large-scale loss of the planet’s most biodiverse ecosystems, especially tropical forests.

The study, led by Xiao-Peng Song and Matthew Hansen of the University of Maryland, is based on analysis of satellite data from 1982 to 2016. The researchers broke land cover into three categories: tall vegetation consisting of trees of at least five meters (16 feet) in height; short vegetation under five meters in height including shrubs, grass, and agricultural crops; and “bare ground”, including urban areas, sand, tundra, and rock. While the classification may seem simplistic, powerful conclusions can be drawn from the data, including assessing agricultural expansion, climate-driven expansion and contraction of ecosystems, and forest clearing and recovery.

“The results of this study reflect a human-dominated Earth system,” the researchers write. “Direct human action on landscapes is found over large areas on every continent, from intensification and extensification of agriculture to increases in forestry and urban land uses, with implications for the maintenance of ecosystem services.”

[Read more…]

More than 2 billion people lack safe drinking water. That number will only grow

Science News reports:

Freshwater is crucial for drinking, washing, growing food, producing energy and just about every other aspect of modern life. Yet more than 2 billion of Earth’s 7.6 billion inhabitants lack clean drinking water at home, available on demand.

A major United Nations report, released in June, shows that the world is not on track to meet a U.N. goal: to bring safe water and sanitation to everyone by 2030. And by 2050, half the world’s population may no longer have safe water.

Will people have enough water to live?

Two main factors are pushing the planet toward a thirstier future: population growth and climate change. For the first, the question is how to balance more people against the finite amount of water available.

India has improved water access in rural areas, but remains at the top of the list for sheer number of people (163 million) lacking water services. Ethiopia, second on the list with 61 million people lacking clean water, has improved substantially since the last measurement in 2000, but still has a high percentage of total residents without access.

Short of any major but unlikely breakthroughs, such as new techniques to desalinate immense amounts of seawater (SN: 8/20/16, p. 22), humankind will have to make do with whatever freshwater already exists.

Most of the world’s freshwater goes to agriculture, mainly to irrigating crops but also to raising livestock and farming aquatic organisms, such as fish and plants. As the global population rises, agricultural production rises to meet demand for more varied diets. In recent decades, the increase in water withdrawal from the ground or lakes and rivers has slowed, whether for agriculture, industries or municipalities, but it still outpaced the rate of population growth since 1940.

That means every drop is increasingly precious — and tough choices must be made. Plant your fields with sugarcane to make ethanol for fuel, and you can’t raise crops to feed your family. Dam a river to produce electricity, and people downstream can no longer fish. Pump groundwater out for yourself, and your neighbor might just want to fight over it. Researchers call this the food-water-energy nexus and say it is one of the biggest challenges facing our increasingly industrialized, globalized and thirsty world. [Continue reading…]

Heat — the next big inequality issue

The Guardian reports:

When July’s heatwave swept through the Canadian province of Quebec, killing more than 90 people in little over a week, the unrelenting sunshine threw the disparities between rich and poor into sharp relief.

While the well-heeled residents of Montreal hunkered down in blissfully air conditioned offices and houses, the city’s homeless population – not usually welcome in public areas such as shopping malls and restaurants – struggled to escape the blanket of heat.

Benedict Labre House, a day centre for homeless people, wasn’t able to secure a donated air-conditioning unit until five days into the heatwave. “You can imagine when you have 40 or 50 people in an enclosed space and it’s so hot, it’s very hard to deal with,” says Francine Nadler, clinical coordinator at the facility.

Fifty-four Montreal residents were killed by this summer’s heat. Authorities haven’t so far specified whether any homeless people were among them, but according to the regional department of public health, the majority were aged over 50, lived alone, and had underlying physical or mental health problems. None had air conditioning. Montreal coroner Jean Brochu told reporters that many of the bodies examined by his team “were in an advanced state of decay, having sometimes spent up to two days in the heat before being found”.

It was the poor and isolated who quietly suffered the most in the heat – a situation echoed in overheated cities across the world. In the US, immigrant workers are three times more likely to die from heat exposure than American citizens. In India, where 24 cities are expected to reach average summertime highs of at least 35C (95F) by 2050, it is the slum dwellers who are most vulnerable. And as the global risk of prolonged exposure to deadly heat steadily rises, so do the associated risks of human catastrophe.

Last year, Hawaiian researchers projected that the share of the world’s population exposed to deadly heat for at least 20 days a year will increase from 30% now to 74% by 2100 if greenhouse gas emissions are allowed to grow. (It will rise to 48% with “drastic reductions”.) They concluded that “an increasing threat to human life from excess heat now seems almost inevitable”. [Continue reading…]