Environment

Light pollution – Chile

It seems nothing can escape the inexorable spread of light pollution — not even the giant telescopes probing the heavens above northern Chile, a region whose pristine dark skies, long considered a paradise for astronomers, are under increasing threat.

The Atacama desert, 1,200 kilometers (750 miles) north of the capital Santiago, provides ideal conditions where astronomers study the stars in darkness so profound they appear like diamonds on velvet.

Scientists estimate that by 2020, Chile — a critically important country for optical and radio astronomy — will host 70 percent of the globe’s astronomical infrastructure.

But the ever-expanding use of cheap light-emitting diode (LED) lighting in the booming South American country is starting to concern astronomers desperately trying to safeguard some of the world’s darkest skies.

“Unfortunately, as we have more and more white lights, the deterioration of the skies has increased by up to 30 percent compared to the end of the last decade,” said scientist Pedro Sanhueza.

Chile takes the problem of light pollution so seriously that Sanhueza heads up an organization called the Office for the Protection of Quality of the Sky (OPCC).

Its main task is to make the people of northern Chile aware of the particularly high night-sky quality and the negative impacts of light pollution.

At the Paranal Observatory deep in the Atacama desert, staff are doing all they can to limit light leaking out into the atmosphere

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Global Warming

First ship crosses Arctic in winter without an icebreaker

A ship has made a winter crossing of the Arctic without an icebreaker for the first time during the coldest period of winter as global warming causes the region’s ice sheets to melt.

The tanker, containing liquefied natural gas, is the first commercial vessel to make such a crossing alone during the winter months.

The voyage is a significant moment in the story of climate change in the Arctic and will be seized on by those with concerns about thinning polar ice and its implications for the environment.

Environment

Global Temperature Extremes

The week’s hottest temperature was 112 degrees Fahrenheit (44.4 degrees Celsius) in Boulia, Queensland.

The week’s coldest temperature was minus 62.0 degrees Fahrenheit (minus 52.2 degrees Celsius) at Vostok, Antarctica.

Temperatures were tabulated from the more than 10,000 worldwide synoptic weather stations. The United Nations World Meteorological Organization sets the standards for weather observations, and provides a global telecommunications circuit for data distribution.

Global Warming

Fiji – Rising Waters

In Fiji, villages need to move due to climate change.

The headman of Vunidogoloa village was born here in 1960 on a river estuary in Natewa Bay, on Fiji’s second-largest island, Vanua Levu.

Today, all that remains of his childhood home is the concrete bathroom foundation and three wooden stumps sticking out of the dark, muddy sand. The beach is just a few metres wide, precariously situated between a grassy elevation leading to the main part of the old village and the bay.

By 2006, regular flooding, soil erosion and the unabated rise of water surrounding their community forced the villagers to ask the Fijian government for help.

In January 2014, Vunidogoloa moved two kilometres inland, becoming the first village in Fiji to relocate because of the effects of climate change.

For much of the world, climate change is a catastrophe unfolding in slow motion, with consequences that can still seemingly be ignored.

But in island nations across the Pacific, climate change has well and truly arrived and is already posing an existential threat to communities.

Rising sea levels have swallowed up five of the Solomon Islands since the mid-20th century.

For Kiribati, a small island nation made up of coral atolls, rising waters pose a threat so dire that in 2014 the government purchased a 20-square-kilometre piece of land in Fiji, to be used to re-settle climate refugees.

Fiji itself has recorded a six-millimetre sea level increase each year since 1993.

Global Warming

Warming is accelerating sea level rise as Greenland and Antarctic ice sheets melt

Melting ice sheets in Greenland and Antarctica are speeding up the already fast pace of sea level rise, new satellite research shows.

At the current rate, the world’s oceans on average will be at least 2 feet (61 cm) higher by the end of the century compared to today, according to researchers who published in Monday’s Proceedings of the National Academies of Sciences.

Sea level rise is caused by warming of the ocean and melting from glaciers and ice sheets. The research, based on 25 years of satellite data, shows that pace has quickened, mainly from the melting of massive ice sheets.

Of the 3 inches (7.5 cm) of sea level rise in the past quarter century, about 55 percent is from warmer water expanding, and the rest is from melting ice.

But the process is accelerating, and more than three-quarters of that acceleration since 1993 is due to melting ice sheets in Greenland and Antarctica, the study shows.

Like weather and climate, there are two factors in sea level rise: year-to-year small rises and falls that are caused by natural events and larger long-term rising trends that are linked to man-made climate change.

Global sea levels were stable for about 3,000 years until the 20th century when they rose and then accelerated due to global warming caused by the burning of coal, oil and natural gas.

Greenland has caused three times more sea level rise than Antarctica so far, but ice melt on the southern continent is responsible for more of the acceleration.

Global Warming

Sun Expected to Dim by 2020

A periodic solar event called a “grand minimum” could overtake the sun perhaps as soon as 2020 and lasting through 2070, resulting in diminished magnetism, infrequent sunspot production and less ultraviolet (UV) radiation reaching Earth — all bringing a cooler period to the planet that may span 50 years.

The last grand-minimum event — a disruption of the sun’s 11-year cycle of variable sunspot activity — happened in the mid-17th century. Known as the Maunder Minimum, it occurred between 1645 and 1715, during a longer span of time when parts of the world became so cold that the period was called the Little Ice Age, which lasted from about 1300 to 1850.

But it’s unlikely that we’ll see a return to the extreme cold from centuries ago, researchers reported in a new study. Since the Maunder Minimum, global average temperatures have been on the rise, driven by climate change. Though a new decades-long dip in solar radiation could slow global warming somewhat, it wouldn’t be by much, the researchers’ simulations demonstrated. And by the end of the incoming cooling period, temperatures would have bounced back from the temporary cooldown.

Environment

Global Temperature Extremes

The week’s hottest temperature was 109 degrees Fahrenheit (42.8 degrees Celsius) in Twee Riviere, South Africa.

The week’s coldest temperature was minus 60.0 degrees Fahrenheit (minus 51.1 degrees Celsius) at Verhoyansk, Siberia.

Temperatures were tabulated from the more than 10,000 worldwide synoptic weather stations. The United Nations World Meteorological Organization sets the standards for weather observations, and provides a global telecommunications circuit for data distribution.

Global Warming

A key part of the Earth’s ozone layer is failing to heal – and Scientists don’t know why

The rescue of the planet’s protective ozone layer has been hailed as one of the great success stories of modern environmental regulation – but on Monday, an international team of 22 scientists raised doubts about whether ozone is actually recovering as expected across much of the world.

“We’ve detected unexpected decreases in the lower part of the stratospheric ozone layer, and the consequence of this result is that it’s offsetting the recovery in ozone that we had expected to see,” said William Ball, a scientist with the Physical Meteorological Observatory in Davos, Switzerland.

In 1987, countries of the world agreed to the Montreal Protocol, a treaty designed to phase out chlorofluorocarbons, or CFCs, responsible for destroying ozone in the stratosphere. The protocol has worked as intended in reducing these substances, and early healing of the ozone “hole” over Antarctica has been subsequently hailed by scientists.

But the study by Ball and his colleagues – a team of scientists including researchers based in the United States, Britain, Canada, Switzerland, Sweden and Finland – focused instead on the lower latitudes where the vast majority of humans live.

There, the scientists found a relatively small but hard-to-explain decline of ozone in the lower part of the stratosphere, the layer of the atmosphere that extends from about six miles to 31 miles above the planet’s surface, since the year 1998. Meanwhile, the upper stratosphere has been recovering.

Environment

A Ticking Time Bomb of Mercury Is Hidden Beneath Earth’s Permafrost

According to a new study published Feb. 5 in the journal Geophysical Research Letters, theremay be more than 15 million gallons (58 million liters) of mercury buried in the permafrost of the Northern Hemisphere — roughly twice as much mercury as can be found in the rest of Earth’s soils, ocean and atmosphere combined. And if global temperatures continue to rise, all that mercury could come pouring out.

In geology, permafrost is defined as any soil that has been frozen for more than two years. In the Northern Hemisphere, permafrost accounts for about 8.8 million square miles (22.79 million square kilometers) of land — or roughly 24 percent of exposed Earth, according to the National Snow and Ice Data Center. Over time, naturally occurring compounds in the atmosphere, such as mercury and carbon dioxide, can bind with organic material in the soil and be frozen into permafrost, potentially remaining trapped underground for thousands of years before it thaws.

Using the mercury contents of 13 cores drilled in various sites across the North American permafrost as a springboard, the researchers estimated the total amount of mercury sealed away below North American permafrost to be roughly 793 gigagrams — or more than 15 million gallons.

Global Warming

Climate Change Affecting USA Military Bases

Military leaders are sounding another alarm about the dangers of climate change, saying in a new report that half of U.S. military sites have already been affected by floods, wildfires, droughts and other weather extremes that are exacerbated by rising global temperatures.

Following a request from Congress, the Defense Department studied climate risks to all 3,500 U.S. military sites around the world. It found nearly 800 had been affected by droughts, 350 by extreme temperatures, 225 by storm surge-related flooding and more than 200 by wildfires, among other weather events.

Climate scientists say those types of extreme weather events have already become more common as global temperatures increase. Sea levels are rising, storms are getting more intense, dry regions are getting drier and fire seasons are getting longer, research shows.

The Defense Department’s report released last week says the military “looks at climate through the lens of its mission,” and that “changes in climate affect national security in several ways.”

Environment

Global Temperature Extremes

The week’s hottest temperature was 110 degrees Fahrenheit (43.3 degrees Celsius) in Moomba, South Australia.

The week’s coldest temperature was minus 55.0 degrees Fahrenheit (minus 48.3 degrees Celsius) at Batamay, Siberia.

Temperatures were tabulated from the more than 10,000 worldwide synoptic weather stations. The United Nations World Meteorological Organization sets the standards for weather observations, and provides a global telecommunications circuit for data distribution

Global Warming

China to develop ‘Polar Silk Road’

China on Friday outlined its ambitions to develop a “Polar Silk Road” of new Arctic shipping lanes opened up by global warming.

Releasing its first official Arctic policy white paper, China said it would encourage enterprises to build infrastructure and conduct commercial trial voyages, paving the way for Arctic shipping routes. China, despite being a non-Arctic state, is increasingly active in the polar region and became an observer member of the Arctic Council in 2013.

The white paper said China is also eyeing development of oil, gas, mineral resources and other non-fossil energies – such as fishing and tourism – in the region.

Global Warming

Ice-Free Yukon

Unusually warm conditions in northwestern Canada have for a second winter in a row prevented a seasonal “ice bridge” from forming over the Yukon River to connect Dawson City with West Dawson.

During summer, the two sides are connected by a ferry, but in winter, residents have to wait for the water to freeze over to make the crossing. The ice bridge has historically been open to traffic by mid-December.

Crews worked for a week to create an “ice Band-Aid” by spraying a cold mist to cap a 300-foot-wide stretch of the river with ice. But the project proved impractical when daytime temperatures didn’t stay below freezing.

The typical Dawson high temperature for January is about minus 8 Fahrenheit.

Environment

‘Doomsday Clock’ Stands at 2 Minutes to Midnight

The “Doomsday Clock,” a hypothetical timepiece that measures humanity’s proximity to destruction by our own actions, hovers perilously close to midnight, the time that denotes global Armageddon.

Today (Jan. 25), the clock has crept even closer to the zero hour. This morning, the Bulletin of the Atomic Scientists (BAS) — an organization of science and policy experts who assess human scientific advancement and risk — revealed the clock’s new “time,” with the hands now standing at 2 minutes to midnight.

The time has only ever been this close to midnight in 1953, following hydrogen bomb tests by both the U.S. and the U.S.S.R., ushering in the era of the first nuclear arms race. In 2018, it reflects the breakdown of global efforts to reduce reliance on and risk of nuclear weapons; increased posturing and threats regarding the use of nuclear weapons; and an insufficient response worldwide to curb the impacts of climate change.

Environment

Global Temperature Extremes

The week’s hottest temperature was 115 degrees Fahrenheit (46.1 degrees Celsius) in Moomba, South Australia.

The week’s coldest temperature was minus 72.0 degrees Fahrenheit (minus 57.8 degrees Celsius) at Majsk, Russia.

Temperatures were tabulated from the more than 10,000 worldwide synoptic weather stations. The United Nations World Meteorological Organization sets the standards for weather observations, and provides a global telecommunications circuit for data distribution.