Earth’s Natural Climate Control Keeps Planet Livable

Posted March 19th, 2014 at 11:03 pm (UTC+0)
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(Atmospheric Infrared Sounder via Wikimedia Commons)

(Atmospheric Infrared Sounder Wikimedia Commons)

A new hypothesis explains why Earth has remained habitable despite natural events that have robbed other planets in our solar system of their ability to host and sustain life.

As the character Goldilocks exclaimed in the classic fairytale, The Story of the Three Bears, Earth is the one planet in our solar system that’s “just right” to maintain the ideal conditions for life to exist, unlike, for example, Mars that’s “too cold” or Venus that’s “too hot.”

Researchers gathered documented evidence to support their new theory said that one reason Earth has stayed livable is because of the various geologic cycles it’s gone through over millions of years and continues to undergo today.

The scientists, from the University of Southern California in Los Angeles and Nanjing University in China, write in the journal Nature that they have found that the geologic cycles — which alternately release and then absorb atmospheric carbon dioxide — act as a form of climate control to keep Earth in balance.

1912 Illustration of Goldilocks running from the 3 bears - from the fairytale (Wikimedia Commons)

1912 Illustration of Goldilocks running from the three bears – from the fairytale (Wikimedia Commons)

Scientists already understood that new or “fresh” rock pushed up through the Earth’s surface when the world’s mountains formed, acting as sort of a sponge, soaking up carbon dioxide, a common greenhouse gas.

However, researchers also noted that if this process of absorbing greenhouse gas continued unabated without any kind of cut-off switch, levels of atmospheric CO2 levels would have been drained to a level that would have caused the Earth to fall into an endless winter a few million years after major mountain ranges such as the Himalayas began to form. Fortunately for all of us, this unrestrained absorption of atmospheric carbon dioxide did not take place.

Researchers involved with this study said that the same fresh rock that served as a sponge to soak up CO2 also produced carbon through a chemical weathering process which replenishes the atmospheric carbon dioxide at a similar rate.

The Himalayas as seen from the International Space Station (NASA)

The Himalayas as seen from the International Space Station (NASA)

“Our presence on Earth is dependent upon this carbon cycle. This is why life is able to survive,” said the Mark Torres, from USC, lead author of the study.

The researchers studied samples of rock taken from the Andes Mountains in Peru.  They noticed an abundance of pyrite or “fool’s gold” among the samples and noted that the chemical breakdown of pyrite produces acids that in turn release CO2 from surrounding minerals.

They realized the fresh rock’s weathering processes, aided by the acid release by surrounding pyrite, produced more carbon than was estimated previously. This led researchers to consider the worldwide consequences of CO2 release brought on by the formation of major mountain ranges about 60 million years ago during the Cenozoic period.

To further explore the link between releases of atmospheric CO2 from weathering rock the researchers looked at marine records of long-term carbon cycles.

Researcher Josh West treks through a valley in Peru in search of evidence of chemical weathering of rocks as they erode. (Photo/courtesy of Mark Torres

Researcher Josh West treks through a valley in Peru in search of evidence of chemical weathering of rocks as they erode. (Mark Torres)

With this information, they were then able to reconstruct the balance between the discharge of CO2 into the atmosphere and absorption of the greenhouse gas from the production of fresh rocks brought on by the uplift of the Earth’s surface during the formation of large mountain ranges.

They found that weathering rock might have played a rather significant, but until now, unseen role in regulating the amount of carbon dioxide released into the atmosphere over the last 60 or so million years.

Lately, a lot of attention has focused on the harm caused to Earth’s climate by increased human-generated atmospheric carbon dioxide, but  the researchers who conducted the US/China study say Earth’s natural geologic system has kept things in balance for millions of years.

Happy Pi Day!

Posted March 14th, 2014 at 6:51 pm (UTC+0)
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Pi Symbol (MarianSigler via Wikimedia Commons)

Pi Symbol (MarianSigler via Wikimedia Commons)

Today, March 14, is a special day for those who are into mathematics or science.  It’s “Pi Day” or “Π Day”, the annual worldwide celebration of the ancient mathematical constant. It’s also the birthday of Albert Einstein who was born on March 14, 1879.

Pi Day has been commemorated in one way or another since physicist Larry Shaw organized the first celebration back on March 14, 1988, while working at a San Francisco museum called the Exploratorium.

Pi, a letter in the Greek alphabet, stands for the ratio of a circle’s circumference to its diameter. Rounded out, it is equal to approximately 3.14.

Historians have tracked the use of a constant ratio in making mathematical calculations as far back as the ancient Babylonians and Egyptians about 4,000 years ago.

In calculating the area of a circle, the ancient Babylonians used a formula that took three times the square of its radius. Some of these calculations set pi to equal 3 and while others have it as 3.125.

According to an ancient Egyptian papyrus, the builders of the Great Pyramids calculated the area of a circle with a formula that set the estimated value of pi as 3.1605.

It's a Pi Pie, created at Delft University of Technology in the Netherlands (Wikimedia Commons)

It’s a Pi Pie, created at Delft University of Technology in the Netherlands (Wikimedia Commons)

It wasn’t until the ancient Greek mathematician Archimedes approximated the area of a circle by using the Pythagorean Theorem that pi was first calculated. He determined pi was equal to a number between 3 1/7 (3.14285714) and 3 10/71 (3.14084507).

Historians have also pointed to calculations made by Zu Chongzhi, a brilliant Chinese mathematician and astronomer who lived about 200 to 300 years before Archimedes. Not much is known about Zu Chongzhi, books of his works have been lost, but he was said to have calculated the value of the ratio of the circumference of a circle to a diameter as 355/113 or approximately 3.14159292.

The use of the Greek letter π to signify the ratio of the circumference of a circle to its diameter was introduced in 1706, by Welsh mathematician William Jones, a close friend of Sir Isaac Newton.

Part of pi’s charm and mystique comes from the fact that it’s a number that can never be fully calculated to an exact value, because it goes on and on indefinitely without repeating or establishing any kind of regular pattern.

Over the centuries, mathematicians, scientists and others have enjoyed the challenge of trying to calculate π to as far of a decimal point as possible.

The current world’s record for calculating pi was set on December 28, 2013, by math enthusiasts and computer scientists Alexander J. Yee of the US and Shigeru Kondo of Japan. The two, using a computer they built, calculated pi to 12.1 trillion digits past the decimal point.

Albert Einstein circa 1947 (Photo: Library of Congress via Wikimedia Commons)

Happy Birthday Albert Einstein! (Library of Congress via Wikimedia Commons)

March 14 is an extra-special day in Princeton, New Jersey. Not only is it Pi Day, but they also celebrate the birth of a famous former resident, physicist and creator of the theories of relativity, Albert Einstein who lived and worked there for over 21 years.

In 1933, as Adolf Hitler and the Nazis were rising to power in Germany, Einstein, who was Jewish, fled his homeland  and settled in Princeton to work at the Institute for Advanced Study.

This year, Pi Day/Albert Einstein’s Birthday in Princeton is a 3-day celebration featuring a Pizza Pi “Top Chef” competition, an Albert Einstein lookalike contest and a Rubik’s Cube demonstration.

So whether it’s a gathering of friends enjoying a Pi Pie, participating in pie-throwing contests, or taking part in competitions to calculate pi to the largest decimal place, have fun! After all, Pi Day only comes once a year.

Are Oceans of Water Hiding Beneath Earth’s Surface?

Posted March 12th, 2014 at 6:32 pm (UTC+0)

Photomicrograph of a grown ringwoodite blue crystal (Jasperox via Wikimedia Commons)

Photomicrograph of a man-grown ringwoodite blue crystal (Jasperox via Wikimedia Commons)

Scientists have discovered the first-ever earthly sample of a water-rich mineral they say provides new proof that there are vast oceans of water deep beneath the Earth’s surface.

The team, led by Graham Pearson from Canada’s University of Alberta, found a mineral called ringwoodite in a sample of rock taken from a Brazilian riverbed. Ringwoodite is a form of the gem-quality mineral peridot. Scientists believe there’s a sizable amount of peridot in part of Earth’s mantle called the transition zone, a high-pressure area located between the lower and upper mantle.

While ringwoodite has been found in meteorites, it hadn’t been previously detected in earthen samples. Its color can range from deep blue to red, violet, or it can even be colorless. Scientists have not been able to do the kind of research to locate ringwoodite because of the depths that would be involved in searching for and retrieving the mineral from its theorized location. The sample of ringwoodite found by the research team was designated a water-rich mineral after the scientists conducted an analysis that indicated that 1.5 percent of its total weight is water.

Researchers said the presence of this water confirms the theories that there are vast bodies of water being held somewhere between 410 and 660 kilometers below the surface of the Earth.

“This sample really provides extremely strong confirmation that there are local wet spots deep in the Earth in this area,” said Pearson. “That particular zone in the Earth, the transition zone, might have as much water as all the world’s oceans put together.”

Graham Pearson holds a diamond that contains the water-rich mineral "ringwoodite" (Richard Siemens - University of Alberta)

Graham Pearson holds a diamond that contains the water-rich mineral “ringwoodite” (Richard Siemens – University of Alberta)

Pearson said that their discovery almost didn’t happen since he and his team were originally looking for another mineral when they first obtained a little hunk of what they referred to as a “three-millimeter-wide, dirty-looking, commercially worthless brown diamond” in 2009. They didn’t spot the ringwoodite until they happened to dig beneath the diamond’s surface.

“It’s so small, this inclusion, it’s extremely difficult to find, never mind work on,” Pearson said, “so it was a bit of a piece of luck, this discovery, as are many scientific discoveries.”

The brown diamond sample Pearson’s team worked with was found in shallow river gravels by Brazilian miners in 2008. The scientists believe the diamond made it to Earth’s surface via a volcanic rock called kimberlite, which has been known to contain diamonds.  Formation of kimberlite takes place deep within the Earth’s mantle and is considered to be one of the deepest of all volcanic rocks.

The research team analyzed their sample of ringwoodite for several years. Among the techniques that were used to confirm the find were Raman and infrared spectroscopy as well as X-ray diffraction.  The team measured the water content of the mineral at Pearson’s Arctic Resources Geochemistry Laboratory at the University of Alberta.

Scientists have debated the structure of Earth’s transition zone; some say the region of the mantle is full of water, while others insist is dry.

(University of Alberta)

(University of Alberta)

Pearson and his team say being able to provide some proof that water does exists deep within the Earth will provide insight to those who study volcanism as well as plate tectonics.

“One of the reasons the Earth is such a dynamic planet is the presence of some water in its interior,” Pearson said. “Water changes everything about the way a planet works.”

The Pearson team’s research and findings are featured in Nature.

Scientists Identify Four New Ozone Depleting Gases in Atmosphere

Posted March 10th, 2014 at 6:46 pm (UTC+0)
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The false-color view of total ozone over the Antarctic pole (l) and Arctic pole (r) on March 6, 2014. The purple and blue colors are where there is the least ozone, and the yellows and reds are where there is more ozone. (NASA)

The false-color view of total ozone over the Antarctic pole (l) and Arctic pole (r) on March 6, 2014. The purple and blue colors are where there is the least ozone, and the yellows and reds are where there is more ozone. (NASA)

Scientists have identified four new man-made gases in the atmosphere that they say are helping to destroy Earth’s protective ozone layer.

Writing in Nature Geoscience, the researchers said that there are about 74,000,000 kilograms of three newly identified chlorofluorocarbons (CFCs) – compounds that only contain the atoms of carbon, fluorine and chlorine – and one new hydrochlorofluorocarbons (HCFC) – hydrogen, carbon, fluorine and chlorine – that have been released into our atmosphere.

The ozone layer, located between the upper troposphere and lower stratosphere, contains a high concentration of an inorganic compound called ozone or trioxygen in the atmosphere.  The ozone layer provides all life on Earth with protection from the harmful effects of the Sun’s radiation.

Model of a Chloroflurocarbon (CFC) molecule (NASA)

Model of a Chloroflurocarbon (CFC) molecule (NASA)

The gasses were identified by the group of scientists as CFC-112 (Tetrachloro-1, 2 – difluoroethane or Freon-112), CFC-112a (Tetrachloro-1, 1 – difluoroethane or Freon-112a), CFC-113a (1, 1, 1 – Trichloro – 2, 2, 2 – trifluoroethane or Freon-113a) and HCFC-133a (Monochlorotrifluoroethane).

The HCFCs are a group of man-made gases that were developed to replace CFC gases as refrigerants and aerosol propellants.  The production of HCFCs grew in the 1980s after nations agreed to phase out the use of CFCs.

While they were considered to be less harmful to the environment than CFCs, HCFCs sometimes referred to as “super greenhouse gases” are also very potent greenhouse gases, despite being in very low concentrations in the atmosphere.

The researchers were able to make their findings by comparing samples of today’s air with air that has been trapped within polar “firn snow”, or the accumulation of snow leftover from previous years, as well as unpolluted air that was sampled between 1978 and 2012 in Tasmania.  The scientists say the polar “firn snow” provided them with a natural archive of the atmosphere that dates back to about a century ago.

Measurements taken by the scientists indicated that all four of the new ozone layer-destroying gases have been released into the atmosphere recently but two them are amassing greatly.

The researchers said that the increase in emissions of the CFCs they studied have not been observed with any other CFC gases since the 1990s when stricter controls were introduced. But they do add that the current emissions are nowhere near the 1980s when the discharge of CFCs was at their peak with around 100,000,000 kilograms of the gases released each year.

“Our research has shown four gases that were not around in the atmosphere at all until the 1960s which suggests they are man-made,” said the study’s lead researcher  Johannes Laube from University of East Anglia..

The ozone cycle (Wikimedia Commons)

The ozone cycle (Wikimedia Commons)

CFC compounds have been identified as the key source of the hole in the ozone layer over Antarctica.

In order to protect the ozone layer, a number of nations around the world signed or ratified the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987 and the agreement went into effect in 1989.  The international agreement sought to reduce and eventually phase out the use of CFCs by 2010.

Many consider the Montreal Protocol to be one of the most successful international agreements ever reached. The atmospheric concentrations of the most harmful CFCs have leveled off or at least have been decreased as a result, but there are various loopholes in the legislation that still allow usage of the CFCs for exempted purposes.

“The identification of these four new gases is very worrying as they will contribute to the destruction of the ozone layer,” said Laube. “We don’t know where the new gases are being emitted from and this should be investigated. Possible sources include feedstock chemicals for insecticide production and solvents for cleaning electronic components.”

Laube said that even if CFC emissions were to stop immediately, their presence would still be detected for many decades to come.

Hubble Watches and Records Rare Asteroid Disintegration

Posted March 7th, 2014 at 7:29 pm (UTC+0)

This series of Hubble Space Telescope images reveals the breakup of an asteroid over a period of several months starting in late 2013. The largest fragments are up to 180 meters in radius. (NASA, ESA, D. Jewitt/UCLA)

This series of Hubble Space Telescope images reveals the breakup of an asteroid over a period of several months starting in late 2013. (NASA, ESA, D. Jewitt/UCLA)

NASA’s Hubble Space Telescope has captured some amazing and breathtaking images since it began scanning the cosmos in 1990.  But, from late last year into early this year, the space telescope was able to capture and record something that, until now, had never been seen before; the breakup of an asteroid located in the asteroid belt between Mars and Jupiter.

Sure, many astronomers have been able to watch comets break apart as they come close to the sun, but they’re much more fragile than asteroids.  Comets, which are basically dirty snowballs, are made mostly of ice and dust.  Asteroids, on the other hand, are chunks of solid rock made of more durable material such as clay, silicate and nickel-iron.  So asteroids are less likely to simply break apart than comets.

“This is a rock, and seeing it fall apart before our eyes is pretty amazing,” said David Jewitt of the University of California at Los Angeles, who led the astronomical forensics investigation.

Designated P/2013 R3, by the International Astronomical Union (IAU), the disintegrating asteroid, was first spotted on September 15, 2013 as an unusual and fuzzy-looking object by astronomers with the Catalina and Pan STARRS sky surveys located in Tucson, Arizona and Maui, Hawaii respectively.

Following-up on these observations about two weeks later scientists with the W. M. Keck Observatory, located atop Mauna Kea, a dormant volcano located on the island of Hawaii, spotted three astronomical bodies moving together and were enveloped in a cloud of dust that was as big as the diameter of Earth.

“The Keck Observatory showed us this thing was worth looking at with Hubble,” said Jewitt. “With its superior resolution, space telescope observations soon showed there were really 10 embedded objects, each with comet-like dust tails. The four largest rocky fragments are up to 400 yards (365.76 meters) in diameter, about four times the length of a (American) football field.”

The Hubble provided data that indicated that the asteroid fragments slowly wandered away from each other at a speed of nearly 1.6093 kilometers-per-hour.

Astronomers said that the P/2013 R3 actually began breaking apart sometime early last year, but newer images of the broken-up asteroid have shown it to split into even more pieces since.

The breakup of asteroid P/2013 R3 (NASA/ESA Hubble Space Telescope)

The break-up of the asteroid, according to those who’ve been observing it, is not likely due to it colliding with another asteroid, because if it had the fragmentation would have been quicker and much more violent compared to its slow and gradual destruction.

The astronomers also noted that such a smash-up of two asteroids would produce debris that would probably travel much faster than what they had observed.

They also don’t think the asteroid became unglued and fell apart because of the pressure of its interior ices warming and vaporizing.

So, this left the astronomers to consider something that’s been discussed before, but never directly observed.  Perhaps the asteroid disintegrated because of what was described as a subtle effect of sunlight, which gradually speeds up the asteroid’s rotation rate.  As the asteroid continues to spin faster and faster, centrifugal force kicks and causes the asteroid to gradually pull itself apart.

For this self-destruct scenario to work, astronomers say that the P/2013 R3 had to have had a weak and fractured interior that was most likely caused by a number of non-destructive collisions with other asteroids.

Scientists are now figuring that most small asteroids in our solar system were probably severely damaged in this way. The break-up of the P/2013 R3, they said, was most likely due to such an asteroid to asteroid collision that took place sometime within the last billion years.

The asteroid belt (shown in white) is located between the orbits of Mars and Jupiter. Other groups of asteroids (in green) (Wikimedia Commons)

The asteroid belt (shown in white) is located between the orbits of Mars and Jupiter. Other groups of asteroids (in green) (Wikimedia Commons)

Looking back at another occasion when they saw six tails springing from asteroid P/2013 P5 along with what they’ve observed with P/2013 R3, astronomers said that they are finding more proof that the pressure of sunlight could very well be the primary factor that has caused our solar system’s small asteroids, those less than 1.6 kilometers across, to disintegrate.

Those following the destruction of P/2013 R3 figure that the remaining debris from the now broken-up asteroid probably weighs about 181,437 metric tons and will mostly likely become a source of future meteoroids.

Astronomers’ figure that most of the remaining debris will eventually plunge into the sun, but a small amount of what’s left of asteroid P/2013 R3 may someday provide a spectacular show for us as they blaze across the sky as meteors.

Have Saturated Fats Been Unjustly Vilified?

Posted March 5th, 2014 at 11:32 pm (UTC+0)
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A big juicy hamburger with bacon, egg and all the trimings (Marshall Astor via Flickr/Creative Commons)

A big juicy hamburger with bacon, egg and all the trimmings (Marshall Astor via Flickr/Creative Commons)

You’d really love to eat a nice juicy hamburger, wouldn’t you?

But maybe you resist the temptation because you’re watching your weight and your doctor wants you to cut down on saturated fats in order to prevent heart disease.

We’re not recommending that you go ahead and splurge on that burger, but a US cardiovascular research scientist says saturated fats have been unfairly vilified and points to carbs as the real health culprit.

Dr. James DiNicolantonio says refined carbohydrates—and not saturated fats—are to blame for the current surge in obesity and diabetes that leads to heart disease.

Writing in the British Medical Journal’s Open Heart cardiology journal, DiNicolantonio says the long-held advice to switch from saturated fats to foods with carbohydrates or omega 6-rich polyunsaturated fats is based on flawed and incomplete data that dates back to 1952.

Starchy foods like breads, pasta and rice are rich in refined carbohydrates (Wikimedia Commons)

Starchy foods like breads, pasta and rice are rich in refined carbohydrates. (Wikimedia Commons)

The 1952 study linked a high-fat diet to deaths from heart disease. DiNicolantonio says the author of that study reached his conclusions based on data from only six out of 22 countries researched and chose to ignore the data from the other 16 nations, because it didn’t match up with the researcher’s hypothesis.

Later analysis of the research data that included all 22 nations actually disproved the study’s conclusions, he says.

The removal of saturated fats from our daily diets got a big boost after US President Dwight D. Eisenhower, who was 64 then, had a heart attack in 1955.

That incident help foster the belief that since saturated fats increase a person’s total cholesterol, then they must also increase the risk of heart disease. Therefore cutting back on saturated fat intake would naturally curb obesity, diabetes and metabolic syndrome.

While he does agree that a low fat-diet may help lower LDL, or “bad” cholesterol, DiNicolantonio points out that there are two types of this bad cholesterol to consider.

He suggests that switching to foods rich with refined carbs could increase one type of cholesterol called “pattern B (small density) LDL,” which can be more dangerous to heart health than “pattern A (large buoyant) LDL.” This, he says, would create a more harmful overall lipid profile, which is the level of compounds in the blood that includes waxes, oils, sterols, triglycerides, phosphatides, and phospholipids.

DiNicolantonio says there are other studies that have shown following a diet low in carbohydrates is better for weight loss and leads to a more improved lipid profile than following a low-fat diet. He also points out that large observational studies have not found any irrefutable proof that a low-fat diet cuts the risk of cardiovascular disease.

(Open Clipart)

(Open Clipart)

Several of the dietary guidelines developed since 1952 also recommend not only a cut in saturated fats, but also an increase in the intake of polyunsaturated fat.

DiNicolantio says an analysis of published trial data has shown that simply replacing saturated fats and trans-fatty acids with foods containing omega 6 fatty acids, without a matching rise in omega 3 fatty acids, seems to increase the risk of death from coronary heart and cardiovascular diseases.

“We need a public health campaign as strong as the one we had in the 70s and 80s demonizing saturated fats, to say that we got it wrong,” said DiNicolantonio.

He considers a diet low in refined carbohydrates, sugars and processed foods to be the best for maintaining good heart health.

He also recommends that anyone who’s had a heart attack not replace saturated fatty foods with those that contain refined carbs or omega 6 fatty acids, especially those that are found in processed vegetable oils that are comprised of large amounts of corn or safflower oil.

Report Provides Further Evidence People Cause Climate Change

Posted March 3rd, 2014 at 7:47 pm (UTC+0)

Cover page to new climate change report (Royal  Society/US National Academy of Science)

Cover page to new climate change report (Royal Society/US National Academy of Science)

New evidence suggests climate change is human caused and that if the release of greenhouse gases continues unabated, changes to the world’s climate will greatly exceed those that have taken place so far.

The new joint report from the US National Academy of Sciences and the Royal Society, the national science academy of the UK, is called Climate Change: Evidence and Causes.  It predicts Earth’s temperature will rise between 5-to-9 degrees Fahrenheit by the end of the century.

“As two of the world’s leading scientific bodies, we feel a responsibility to evaluate and explain what is known about climate change, at least the physical side of it, to concerned citizens, educators, decision makers and leaders, and to advance public dialogue about how to respond to the threats of climate change,” said the USNAS President Ralph  Cicerone.

Even if the release of greenhouse gases were stop immediately temperatures would continue to rise, according to the report.

Arctic ice melt impacts nature (Agrant141 via Wikimedia Commons)

Arctic ice melt impacts nature (Agrant141 via Wikimedia Commons)

“If greenhouse gas emissions were to suddenly stop, the earth would not cool to preindustrial levels for thousands of years,” said Inez Fung, the U.S. lead author of the report from the University of California, Berkeley. “The actions of today have long-term effects. Stopping emissions now doesn’t mean we can remove the carbon dioxide that is already in the atmosphere. The accumulation of CO2 in the atmosphere causes continued rises in temperatures and sea levels.”

The report is written in easy-to-understand English, addresses 20 important issues in a question-and-answer format, and explains which characteristics of climate change are well established and documented as well as those that aren’t which require further investigation.

“Climate change is a dividing issue of our times,” said Paul Nurse, head of the Royal Society. “Policy decisions are made on the world stage. This is a simple but authoritative account of the major issues of climate change. It’s a reliable guide to the science – a guide that’s necessary for an informed debate.”

This visualization shows a running five-year average global temperature, as compared to a baseline average global temperature from 1951-1980. (NASA GISS)

This visualization shows a running five-year average global temperature, as compared to a baseline average global temperature from 1951-1980. (NASA)

According to the report, current atmospheric C02 levels have risen to a level that hasn’t been seen in about 800,000 years. A review of observational data dating back to the mid-19th century has shown a definite long-term warming trend. Researchers have found that, since 1900, Earth’s average surface air temperature has increased by about 1.4 degrees Fahrenheit and that much of that rise took place in the mid-1970s.

Measurements made by the American and British teams that prepared the report show the increase of atmospheric C02 has been mostly caused by combustion of fossil fuels and not due to naturally occurring phenomena such as changes in the sun’s output as some have suggested.

Two people brave the extreme cold temperatures in Chicago (wind chills of -40 degrees F) on 1/6/14 when a whirlpool of frigid dense air known as a "polar vortex" descended Monday into much of the U.S. Some scientists suggest the extreme winter weather is a result of climate change. (AP Photo/Charles Rex Arbogast)

Two people brave the extreme temperatures in Chicago on Jan. 6, 2014, when a “polar vortex” descended on much of the U.S.(AP)

The reduction in Arctic sea ice, a rise in ocean temperatures as well as changes in nature like the movement of temperature-sensitive species of fish, mammals, insects toward the poles, provide irrefutable evidence of planetary-scale warming, said the report authors.

A number of people living along the East Coast have questioned climate change after being hit with extreme weather conditions this winter brought on by polar vortices. Even with spring only a couple of weeks away, the mid-Atlantic region of the US is being hit today by a major winter storm that has brought with it very cold temperatures as well as treacherous accumulations of snow and ice.

But Fung suggests that climate change may be responsible for the harsh winter weather as well as other forms of extreme weather such as record heat, drought or rainfall.

“A warmer atmosphere can hold more moisture so when it rains, there’s more rain,” she said. “Rainfall will be more intense. Heat waves will become more frequent. We expect droughts, when they occur, will be more severe. There will always be cold nights and cold days in this warming trend, but they will be rarer and rarer.”

NASA, ESA Ramp Up Planet-hunting Missions

Posted February 28th, 2014 at 8:33 pm (UTC+0)
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Artist concept depicts multiple-transiting planet systems - stars with more than one planet orbiting it - that have been discovered recently by NASA's Kepler mission. )(NASA)

Artist conception of multiple transiting planet systems – stars with more than one planet orbiting it – discovered recently by NASA’s Kepler mission. (NASA)

NASA’s planet-hunting Kepler mission stirred up excitement this week when mission officials announced they’d hit the proverbial jackpot – discovering and confirming a record 715 new planets orbiting 305 stars.

Nearly 95 percent of these newly found planets are smaller than Neptune, but four are about 2.5 times bigger than Earth and are located within what scientists call the habitable zone, meaning they are just the right distance from their parent stars for liquid surface water, an important element of life, to form.

Artist rendering of NASA's TESS - Transiting Exoplanet Survey Satellite in space (NASA)

Artist rendering of NASA’s TESS – Transiting Exoplanet Survey Satellite in space (NASA)

Even though the spacecraft was hobbled last summer after experiencing problems with accurately pointing its telescope, Kepler accumulated so much observational data during its operational time that astronomers will have plenty of information to wade through which could lead to possible new discoveries.

Meantime, NASA and the European Space Agency (ESA) aren’t wasting any time preparing the next generation of planet-hunting missions.

NASA plans a 2017 launch of its Transiting Exoplanet Survey Satellite (TESS). The TESS space telescope, which will be equipped with an array of telescopes, will conduct an all-sky survey.

TESS will be on the lookout for a variety of transiting exoplanets – planets that are detected when their host stars dim as they pass – that orbit the nearest and the brightest stars the sky.

TESS will look for and identify gas giant planets as well as Earth-like planets orbiting within their host stars’ habitable zone.

WFIRST-AFTA (Wide Field Infrared Survey Telescope - Astrophysics Focused Telescope Assets) rendering of on-orbit situation. (Mark Melton, NASA/GSFC)

Artist rendering of WFIRST – Wide Field Infrared Survey Telescope (NASA)

Sometime in the early 2020s, NASA plans to launch an ambitious mission called The Wide Field Infrared Survey Telescope (WFIRST).

The WFIRST is an infrared space observatory that will not only join the search for potentially habitable extrasolar planets, but will help scientists learn more about the nature of dark energy and why the universe is rapidly expanding.

Scientists are also hoping WFIRST will help them learn more about how stars, galaxies and black holes form and evolve.

Just last week, ESA announced it has green-lighted an initial six-year mission that will join the search for alien planets orbiting within neighboring star systems.

The Planetary Transits and Oscillations of stars (PLATO), a space-based observatory, will launch on a Soyuz rocket from Europe’s Spaceport in Kourou, French Guiana, sometime between 2022 and 2024.

An artist's drawing of one of ESA's proposed PLATO space telescopes - notice the bank of 34 telescopes.(© ESA)

An artist’s drawing of one of ESA’s proposed PLATO space telescopes. Notice the bank of 34 telescopes.(© ESA)

PLATO will feature 34 separate telescopes  searching for planets among up to a million stars.

ESA said PLATO will observe and monitor stars that are relatively nearby and will look for planets, especially those that are Earth-like and super-Earth-like, that transit in front of them.

Along with looking for planets located in a star’s habitable zone, PLATO will also examine seismic activity in a discovered planet’s host star enabling scientists to learn more factors such as its mass, radius and age.

ESA officials are also planning to couple various measurements made by PLATO along with ground-based radial velocity observations. Joining data from these two sources should help scientists calculate an exoplanet’s mass and radius so they can get an idea its composition.

Ancient Zircon Reveals Age of Earth’s Crust

Posted February 26th, 2014 at 5:43 pm (UTC+0)

A 4.4 billion-year-old zircon crystal, the oldest confirmed piece of the Earth's crust, is providing new insight into how the early Earth cooled from a ball of magma and formed continents just 160 million years after the formation of our solar system, much earlier than previously believed.  (John Valley)

A 4.4 billion-year-old zircon crystal provides insight into how the early Earth cooled from a ball of magma 160 million years after the solar system formed. (John Valley)

A tiny sliver of ancient zircon reveals the crust of our planet formed at least 4.4 billion years ago—160 million years after the birth of the solar system, according to a new study.

Earth itself is believed to be about 4.5 billion years old.

The researchers examined some of the oldest materials ever found on the planet to reach their conclusions, which were published in Nature Geoscience.

They say the ancient zircon provides evidence Earth cooled from a blazing ball of fire covered by a magma ocean much more quickly than previously thought.

“This confirms our view of how the Earth cooled and became habitable,” said research leader John Valley, a professor of geoscience at the University of Wisconsin, Madison. “This may also help us understand how other habitable planets would form.”

Valley said that his team’s study provides further support for the “cool early Earth” theory which suggests the planet’s temperatures dropped low enough to allow liquid water to accumulate and pool into oceans soon after Earth’s crust formed from molten rock..

The team’s work follows up previous studies which used lead isotopes to date the zircon crystals found in the Jack Hills region of Western Australia.

Research from Valley’s team showed the zircons crystallized some 4.4 billion years ago as Earth cooled from its previous molten state. They were also able to confirm the Australian zircon crystals they studied were the oldest known material of any kind to form on Earth.

“The study reinforces our conclusion that Earth had a hydrosphere before 4.3 billion years ago,” and possibly life not long after,  Valley said.

 A timeline of the history of our planet places the formation of the Jack Hills zircon and a   "cool early Earth" at 4.4 billion years. (Andree Valley)

A timeline of the history of our planet places the formation of the Jack Hills zircon and a
“cool early Earth” at 4.4 billion years ago. (Andree Valley)

The researchers used a new technique called atom-probe tomography, as well as secondary ion mass spectrometry, to make their findings.

These research methods allowed the team to calculate the mass of individual atoms of lead contained within the zircon sample.

In doing so, the researchers were able to precisely measure both the zircon’s age as well as its thermal history.

Valley said he and his team noticed the lead atoms were clustered together, rather than being randomly scattered throughout the sample, as had been predicted.

They were like “raisins in a pudding,” he said.

The researchers found those clumps of lead atoms formed one billion years after the zircon crystallized. The lead atoms themselves, according to the scientists, had been created by the radioactive decay of uranium and were then disbursed into clusters within the zircon when the crystals were reheated.

Location of the Jack Hills in Australia where the oldest piece of Earth's crust was found (NASA Earth Observatory)

Location of the Jack Hills in Australia where the oldest piece of Earth’s crust was found (NASA)

“The zircon formed 4.4 billion years ago, and at 3.4 billion years, all the lead that existed at that time was concentrated in these hotspots,” Valley said. “This allows us to read a new page of the thermal history recorded by these tiny zircon time capsules. The Earth was assembled from a lot of heterogeneous material from the solar system.”

Early in its existence, Earth underwent an intense bombardment of meteors and about 4.5 billion years ago, also collided with an object the size of Mars.

This massive collision “formed our moon, and melted and homogenized the Earth. Our samples formed after the magma oceans cooled and prove that these events were very early,” said Valley.

Scientist Proposes New DNA-based Naming System for All Living Organisms

Posted February 21st, 2014 at 10:00 pm (UTC+0)
1 comment

DNA helix

DNA helix

All living organisms on Earth could soon have a new name if a Virginia Tech professor has his way.

Boris Vinatzer has developed a system that classifies and names organisms based on their genome sequence.

His study was published today in PLoS One.

Vinatzer says his new system would provide scientists and others with a much more precise and clear “universal language” that could make communicating about all life on Earth easier.

Adopting his system would provide each of Earth’s organisms, whether it’s a bacterium, plant, fungus or animal, with a heartier, more detailed and useful name, according to Vinatzer.

The naming system is based on the one devised in the 18th century by Carl Linnaeus (aka Carl von Linné), a Swedish botanist, physician, and zoologist, who is often referred to godfather of genus (taxonomic rank). The Linnaeus classification system has been used by scientists worldwide for more than 200 years.

Carl Linnaeus is a botanist who in the 18th century devised a system for classifying living things that is still used today. (Wikimedia Commons)

Carl Linnaeus is a botanist who in the 18th century devised a system for classifying living things that is still used today. (Wikimedia Commons)

Genome sequencing technology has progressed immensely in recent years and it now allows us to distinguish between any bacteria, plant, or animal at a very low cost,” said Vinatzer, who is with Virginia Tech’s Fralin Life Science Institute. “The limitation of the Linnaeus system is the absence of a method to name the sequenced organisms with precision.”

Rather than completely change the current naming convention of biological classification, Vinatzer sees his system more as a way to add more specific defining data to the classification of every organism within its already named species.

Since the naming system would depend on an organism’s specific genetic code, he says it would allow for a much quicker and more universal way of identifying new life forms.

The system begins with the sampling and sequencing of an organism’s DNA.

The sequenced DNA is then used to produce unique code that is specific to that individual organism, but is also based on its similarity to other like organisms that have already been sequenced.

Scientist Boris Vinatzer at work in his lab ( Virginia Tech)

Scientist Boris Vinatzer at work in his lab ( Virginia Tech)

Unlike the current method of biological classification where the names of organisms may change and vary over time, Vinatzer says the code system would make names  permanent and standardized.

He also says that naming life forms based on his proposed code system would be faster than today’s long and detailed process that requires analyzing one organism’s physical characteristics compared to another’s.

Back in 2009, Vinatzer and a colleague had success with using genome sequencing to trace a pathogen that was devastating kiwifruit crops around the world back to China.

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