Environment

Amazon Mining

An Amazon nature reserve created in 1984 by Brazil’s then-military government, and believed to be rich in gold and other minerals, was at least temporarily saved from being abolished.

A federal court in the capital of Brasilia blocked President Michel Temer’s decree that would have opened up about 30 percent of the area to mining.

The mining and energy ministry said that the reserve’s protected forest and areas inhabited by indigenous people in relative isolation would not have been affected.

Conservation groups and opposition politicians denounced the president’s attempt as “the biggest attack on the Amazon of the last 50 years.”

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Global Warming

Climate Change Is Causing Fish to Shrink

Fishermen over the past several years have noted that fish appear to be shrinking. That observation was validated in 2014 by research that found commercially important fish stocks in the North Sea, such as sole, herring, and haddock, have decreased in maximum body size over a 40-year period.

New research published in the journal Global Change Biology explains that these species and many others are ectotherms, meaning that their body temperature depends on environmental temperature.

As the oceans warm up, their bodies will do so as well. Higher temperature within the scope that the fish can tolerate generally increases the rate of biochemical reactions in the fish’s body and thus increases their body metabolic rate. Metabolic rate refers to an animal’s oxygen consumption, which also naturally increases as fish grow into adulthood because their body mass becomes larger.

One might wonder why fish and other marine ectotherms aren’t just taking in ever more oxygen to coincide with this natural growth due to maturation and the rise of ocean temperatures. They don’t because at a certain point they cannot keep up.

The researchers point out that the surface area of an animal’s gills — where oxygen is obtained — does not grow at the same pace as the rest of its body. This is because gills, in order to work, must function as a two-dimensional surface — width by height — and thus cannot grow as fast as the three-dimensional volume — width by height by depth — they have to supply with oxygen.

The reductions will be in the range of 20–30 percent if ocean temperatures continue to climb due to climate change. At the higher end of that range is one of the world’s most important commercial fish: tuna.

Tunas are active, mobile, and fast-swimming animals that need a lot of oxygen to maintain their lifestyle. They have to keep swimming non-stop in order to get more water through their gills to obtain sufficient oxygen. Thus, when temperature increases, they are particularly susceptible to not having sufficient oxygen to support their body growth.

For a 2 degree Celsius (3.6 degree Fahrenheit) increase in water temperature, which is approximately what is expected to occur in oceans around the world by the mid-21st century, tunas such as the Atlantic bluefin tuna will potentially decrease in body size by 30 percent.

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Global Warming

Climate Change is disrupting the ‘birds and the bees’

Over the last two decades, scientists have found that warmer temperatures are quietly spoiling the mood, making it harder for plants and animals to reproduce.

While humans and many other animals determine sex genetically, many reptiles and some fish use the incubation temperature of the eggs to set the gender of their offspring. This means that changing global temperatures could alter the ratio of sexes produced, making it harder for these animals to find mates.

Eastern three-lined skunk females can partially compensate for temperature increases by digging deeper nests and laying earlier in the season. Nevertheless, according to a study published in 2009, their nests still warmed by 1.5C over 10 years. This shifted the sex ratio towards females.

Not every species is as badly affected. Australian water dragon females have been shown to buffer temperature differences of 4C by nesting in sunnier or shadier locations. When it comes to climate change, behavioural flexibility is often a big advantage.

In the plant world, temperature can influence sex ratios in more subtle ways. For example, the tobacco root plant, which lives in alpine meadows in North America, has been producing ever more male plants over the last 40 years. This may be due to reduced water availability, since females require more water to develop. So far, the extra males have actually boosted seed production, but if the trend continues, the lack of females could eventually leave male tobacco roots feeling a little lonely.

Meanwhile, the majority of the world’s sea turtles use temperature to set the sex of their offspring. “Embryos are laid with no gender,” says Graeme Hays of Deakin University in Australia. “They can develop into males or females.” Warmer eggs develop into females, cooler eggs into males. “Temperature during the middle third of incubation controls the sex,” says Hays, by switching on and off the genes that trigger development into either a male or a female.

The difference between male and female is just a couple of degrees. That means even slight changes in the climate could skew the sex ratio, making males harder to find. Incubation temperatures above 29C are predicted to produce increasingly female-biased clutches.

There is evidence that this shift is already underway. Over the last century, the sex ratios of green turtles, hawksbill turtles and leatherback turtles have become increasingly sex-biased. By 2030, the percentage of male green turtles produced has been predicted to drop to just 2.4%. “All else being equal, a warming climate will produce more female sea turtle hatchlings,” says Hays.

One solution for sea turtles and other reptiles with temperature-based sex determination is to breed at different times of year. This is called a “phenological shift”. “Earlier nesting may mean that sea turtles avoid incubation conditions that are too hot,” says Hays.

Phenological shifts are common, because many animals use environmental cues like temperature and rainfall to time key events like migration, flowering and breeding. Climate change is changing the timing and strength of the seasons, and as these cues change, the annual ebb and flow of the natural world is being disrupted.

In fact, one of the first pieces of evidence for the effect of climate change on living things was the discovery that plants are flowering earlier and earlier each year. In 2002, a landmark study showed that 385 British plant species were flowering on average 4.5 days earlier than in the 1990s. The same story is playing out across the globe: a 2008 meta-analysis looked at 650 temperate plant species in Europe, Asia and North America, and found that spring flowering had advanced by 1.9 days per decade on average.

The biggest concern is that plants and their pollinators might respond differently to climate change, leading to a mismatch that could significantly affect plant reproduction. For instance, in Japan the flowering of the plant Corydalis ambigua has advanced faster than the emergence of its bumblebee pollinators, resulting in a mismatch that reduces seed production in years with an early spring. Such mismatches could have a major impact on certain crop plants.

Environment

Death Valley Breaks Record for Hottest Month Ever in the US

July temperatures in Death Valley have incinerated previous records.

With an average daily high temperature of 107.4 degrees Fahrenheit (41.9 degrees Celsius), July was the valley’s hottest month on record, blazing through the former record of 107.2 degrees F (41.8 degrees C) set in 1917.

Temperatures in Death Valley in July blazed into the record books not only as the hottest month in the desert valley in eastern California but also as the hottest month ever recorded in the United States.

During July, temperatures were at their lowest at around 5 a.m. local time, averaging about 95 degrees F (35 degrees C).

Death Valley’s highest temperatures during July were 127 degrees F (52.8 degrees C) on July 7; 126 degrees F (52.2 degrees C) on July 8; and 125 degrees F (51.7 degrees C) on July 31,

Global Warming

Temperature and salinity double in Mediterranean

The Mediterranean is responding very quickly to global warming and the rate of evaporation is higher than precipitation and fluvial supply. Temperatures and salinity is also increasing at two and a half times the rate at the midway point in the twentieth century and higher than that of the oceans, according to research published in Scientific Reports.

The data of the study shows that since the end of 1993 until today, the temperature and salinity of the water coming from the eastern Mediterranean, between 300 and 600 meters below sea level, have experienced significant variations. In particular, the rapidity with which they are increasing is two and a half times that seen in the eastern Mediterranean in the second half of the twentieth century and is much higher than that seen in oceans.

Environment

Sizzling Shanghai, China

Shanghai registered on July 21 its hottest day since records began in 1872 as a stubborn heat wave baked much of China. The new record of 40.9 degrees Celsius (106 F) broke the previous record of 40.8 set in 2013.

Chinese meteorologists say Shanghai is getting hotter, with eight of the 12 highest temperatures over the past century occurring during the past five years.

Shanghai’s weather bureau blamed the heat on a stubborn subtropical high and southwesterly winds that are predicted to last until early August. That’s when the typhoon season typically arrives in eastern China.

Atomic Paradise

Even though it’s still unsafe for people to live on Bikini Atoll, marine life is thriving 60 years after a series of 23 atomic blasts left it saturated with radiation.

Scientists from Stanford University say coconut crabs, coral and other species that have managed to re-emerge on Bikini show barely any genetic differences from those living in uncontaminated parts of the Pacific.

Lead researcher Stephen Palumbi believes that at least the coral have mechanisms to protect their genetic information from radiation.

Environment

Humans Have Produced Whopping 9 Billion Tons of Plastic

A new study, which is the first global analysis of all mass-produced plastics ever made, finds that since large-scale manufacturing of plastics took off in the 1950s and until 2015, humans have produced approximately 9 billion tons (8.3 billion metric tons) of plastic.

To put that in perspective, all that plastic would be equivalent to 85,567 aircraft “supercarriers” like the USS Gerald R. Ford, which weighs 107,000 tons (97,000 metric tons).

Of those 9 billion tons, half was made in the last 13 years, said Roland Geyer, an associate professor of industrial ecology at the University of California, Santa Barbara, and lead author of the new study, which was published online today (July 19) in the journal Science Advances.

As of 2015, about 7 billion tons (6.3 billion metric tons) of plastic have been disposed of as waste, with only 9 percent of it recycled, 12 percent incinerated, and a whopping 79 percent finding its way into landfills, the researchers report.

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Environment

Longevity Barrier?

New research suggests the maximum human lifespan could far exceed the 115-year limit cited in a previous study, after decades of increasing longevity.

Geneticist Jan Vijg of New York’s Albert Einstein College of Medicine authored a controversial report last year that says humans have reached our maximum allotted lifespan for the first time.

But other researchers quickly argued that Vijg’s findings were skewed by flawed calculations.

Siegfried Hekimi from Montreal’s McGill University argues that under more optimistic interpretations of longevity data, the oldest person alive in 2300 would be about 150 years old.

Environment

Sixth mass extinction

Many scientists say it’s abundantly clear that Earth is entering its sixth mass-extinction event, meaning three-quarters of all species could disappear in the coming centuries.

But that’s not even the full picture of the “biological annihilation” people are inflicting on the natural world, according to a study published Monday in the Proceedings of the National Academy of Sciences. Gerardo Ceballos, an ecology professor at the Universidad Nacional Autónoma de México, and his co-authors, including well-known Stanford University biologist Paul Ehrlich, cite striking new evidence that populations of species we thought were common are suffering in unseen ways.

Their key findings: Nearly one-third of the 27,600 land-based mammal, bird, amphibian and reptile species studied are shrinking in terms of their numbers and territorial range. The researchers called that an “extremely high degree of population decay.”

The scientists also looked at a well-studied group of 177 mammal species and found that all of them had lost at least 30% of their territory between 1900 and 2015; more than 40% of those species “experienced severe population declines,” meaning they lost at least 80% of their geographic range during that time.

Looking at the extinction crisis not only in terms of species that are on the brink but also those whose populations and ranges are shrinking helps show that “Earth’s sixth mass extinction is more severe” than previously thought, the authors write. They say a major extinction event is “ongoing.”

Global Warming

Oozing Methane Blasts Holes in Siberian Tundra

Escaping methane gas has blown at least two new holes in the Siberian tundra in the past few months, according to eyewitness accounts to the Siberian Times and the Russian Academy of Sciences.

Reindeer herders northwest of the village of Seyakha in Siberia’s far north reported seeing an eruption of fire and smoke on the morning of June 28 — an event caught on seismic sensors at 11 a.m. local time, according to The Siberian Times. Scientists visiting the site photographed a fresh crater blown into the banks of a river.

Researchers also discovered a second, previously unknown crater in the Tyumen region of Siberia this month.

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Global Warming

Ozone Killer

The slow healing of Earth’s ozone hole is being held back by the use of an unregulated chemical that continues to damage the UV protection layer 30 years after most ozone-destroying compounds were banned.

Scientists at the University of Lancaster say atmospheric levels of dichloromethane, a short-lived, ozone-depleting substance used in paint strippers, are on the rise. It isn’t covered under the 1987 Montreal Protocol.

Global Warming

Coastal Louisiana Is Sinking Faster Than Expected

The rich wetlands of southern Louisiana are sinking faster than previously thought, new data reveals, worsening a decades-long ecological disaster that authorities are struggling to reverse.

“What previous studies have called the worst case is the case that right now is the average,” said Jaap Nienhuis, a geologist at Tulane University in New Orleans.

Nienhuis and his colleagues at Tulane have found the coast is subsiding on average about 9 mm (1/3 inch) a year. Some areas, such as those near the mouth of the Mississippi and the Atchafalaya River delta to the west, are settling closer to 12 mm a year.

Periodic flooding of the Mississippi River used to dump fresh soil into those marshes, bolstering the wetlands. But the levees that now prevent those floods keep that soil straitjacketed in the river. The area is also home to a major oil and natural gas industry, and canals cut through the marshes allowed salt water to kill grasses that held the land in place.

As a result, coastal Louisiana has been losing a roughly Manhattan-sized chunk every year to a combination of sea-level rise, erosion, and subsidence. That threatens a rich ecosystem that provides more than 1 billion pounds of seafood a year and provides a buffer when hurricanes spin onto shore from the Gulf of Mexico.

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Environment

The Gulf of Mexico’s ‘Dead Zone’

The oxygen-poor “dead zone” in the Gulf of Mexico may be the biggest on record this year, nearly doubling in size to cover an area of ocean as large as Vermont, scientists at Louisiana State University estimate.

The dead zone develops when nitrogen-rich runoff from the Midwestern farm belt pours into rivers and out into the Gulf. That runoff is loaded with fertilizer, as well as nutrients from animal and human waste, and it fuels the growth of algae that die, sink, and decompose, depleting oxygen levels offshore. That drives away marine life in the zone — or kills species that can’t escape.

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Global Warming

Drowning Communities

Isle de Jean Charles, a small island in southeastern Louisiana’s bayous, is drowning as the Gulf of Mexico rises. Twenty-nine homes remain, housing 100 people, but they are all being relocated because the flooding is unstoppable. The island has already lost 98% of its land since 1955, making it one of the most visible victims of climate change — so far. The residents can either leave their homes or die in them, and they are leaving.

Climate change is affecting larger coastal areas in the U.S., from Alaska down to Florida and Louisiana. Climate-induced migration is now a concrete reality for US citizens, not an abstract idea for politicians to talk about.

Global Warming

Hotter Cities

New research finds that a combination of global warming and localized heating due to the urban heat island (UHI) effect could cause some of the world’s cities to be as much as 14 degrees Fahrenheit warmer by the end of this century.

The UHI effect occurs as buildings, roadways and other man-made structures store far more heat than natural settings, especially after the sun goes down. This amplifies the local warming effects of climate change, according to a report published in the journal Nature Climate Change.

Scientists recommend painting roofs a reflective white and planting more trees to limit urban warming.