Tag: Earths

Without oxygen, Earth’s early microbes relied on arsenic to sustain life

Credit: CC0 Public Domain

Much of life on planet Earth today relies on oxygen to exist, but before oxygen was present on our blue planet, lifeforms likely used arsenic instead. These findings are detailed in research published today in Communications Earth and Environment.

A key component of the oxygen cycle is where plants and some types of bacteria essentially take sunlight, water, and CO2, and convert them to carbohydrates and oxygen, which are then cycled and used by other organisms that breathe oxygen. This oxygen serves as a vehicle for electrons, gaining and donating electrons as it powers through the metabolic processes. However, for half of the time life has existed on Earth, there was no oxygen present, and for the first 1.5 billion years, we really don’t how these systems worked, says lead author of the study and UConn Professor of Marine Sciences and Geosciences Pieter

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A Giant Leap Towards Defeating Astronomy’s Greatest Enemy: Earth’s Atmosphere

In astronomy, seeing farther and fainter than ever before requires three simultaneous approaches.

1.) Building bigger telescopes, gathering more light and yielding higher resolutions.

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Famed NYC clock is counting down to Earth’s climate change ‘deadline’

Anyone who has walked through New York City’s Union Square and managed to look up has seen it: A large, multi-numeral digital clock embedded on the side of a sky scraper. 

The public art project known as Metronome typically counts the hours, minutes, and seconds to and from midnight. But as of Saturday, it began telling a different sort of time. It now marks the years, days, hours, minutes, and seconds that the world has to limit carbon emissions before we reach a critical tipping point.

Artists Andrew Boyd and Gan Golan reprogrammed the clock to coincide with the beginning of Climate Week in NYC. The “climate clock,” as they call it, will display on Metronome through the end of Climate Week, Sept. 27.

The “deadline” they’ve set is based on calculations from the Mercator Research Institute on Global Commons and Climate Change. It is largely understood that 1.5 degrees

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The Enduring Mystery of Earth’s Water

You have to go to extreme lengths to find places on Earth that don’t reveal that they’re part of a water-rich planet. Even the highest and driest deserts, like the Atacama Plateau in South America, still get a minimum of a couple of millimeters of annual precipitation on average (although there are places where we don’t yet know what the average is because it’s simply not rained for years). And if you whip out your handy mass spectrometer on a desert walkabout the chances are that you’ll be able to detect at least a few atmospheric water molecules.

Go elsewhere, and it’s hard to imagine anything but a water-logged world. More than 70 percent of Earth’s surface is covered in oceans and roughly 97 percent of the surface water is in those oceans, leaving a scant 1 percent as freshwater. Water is also seldom static, whether it’s flowing in ocean

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Earth’s Van Allen radiation belts double as particle accelerator

Sept. 10 (UPI) — Electrons in the radiation belts surrounding Earth can be accelerated to extreme speeds across short distances, according to a study published Thursday in the journal Nature Communications.

The Earth’s magnetic field traps high energy particles — mostly from the sun — in what are known as the Van Allen radiation belts, named for the astronomer who discovered them.

In 2012, NASA launched a pair of spacecraft, called the Van Allen Probes, to study the mechanics of the magnetosphere. The probes observed plasma waves and measured the speed and trajectory of a wide range of particles.

Data collected by the Van Allen Probes showed electrons in the radiation belts can achieve ultra-relativistic energies — or reach high speeds. Because the electrons move so fast, their energy of motion is greater than their energy of rest, causing the flow of time to significantly slows down for these particles.

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New insight on the impacts of Earth’s biosphere on air quality

Credit: CC0 Public Domain

A new study led by a team of University of Minnesota researchers provides the first global satellite measurements of one of the most important chemicals affecting Earth’s atmosphere.

Isoprene is a natural hydrocarbon emitted to the atmosphere in vast quantities—approximately 500 billion kg per year—by plants and trees. Isoprene is chemically reactive, and once in the atmosphere it combines with human-caused pollutants to adversely affect air quality. Isoprene also reacts with the main atmospheric oxidizing agent—called OH radicals—and therefore reduces the capacity of the atmosphere to scrub itself of pollutants and greenhouse gases.

Scientists look to atmospheric models to predict current and future atmospheric composition and air quality, as well as to diagnose the atmosphere’s ability to remove greenhouse gases and air pollutants. But isoprene emission rates are highly uncertain due to sparse ground-based measurements, and scientists are also unsure of the extent to which isoprene

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Earth’s ice sheets tracking worst-case climate scenarios

The Greenland and Antarctic ice sheets, which hold enough frozen water to lift oceans 65 metres, are tracking the UN’s worst-case scenarios for sea level rise, researchers said Monday, highlighting flaws in current climate change models.

Mass loss from 2007 to 2017 due to melt-water and crumbling ice aligned almost perfectly with the Intergovernmental Panel for Climate Change’s (IPCC) most extreme forecasts, which see the two ice sheets adding up to 40 centimetres (nearly 16 inches) to global oceans by 2100, they reported in Nature Climate Change.

Such an increase would have a devastating impact worldwide, increasing the destructive power of storm surges and exposing coastal regions home to hundreds of millions of people to repeated and severe flooding.

That is nearly three times more than mid-range projections from the IPCC’s last major Assessment Report in 2014, which predicts a 70-centimetre rise in sea level from all sources, including mountain

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