Freak Storms Likely in Coming Years

We define ‘grey swan’ tropical cyclones as high-impact storms that would not be predicted based on history but may be foreseeable using physical knowledge together with historical data.

reaching_critical_mass_m

The analysis by Ning Lin of Princeton University and a colleague showed that surges generated by grey swans striking Tampa or Cairns could reach six metres (20 feet), and four metres for Dubai.

The damage caused by grey swans, as with all cyclones and hurricanes, is mostly from storm surges, which can be enhanced by higher water levels and tides.

Hurricane Katrina, which left 1,500 people dead and caused some $75 billion (68 billion euros) in damages in 2005, exemplified the destructive potential of such surges.

nclimate2777-f1

Here we apply a climatological–hydrodynamic method to estimate grey swan tropical cyclone storm surge threat for three highly vulnerable coastal regions. We identify a potentially large risk in the Persian Gulf, where tropical cyclones have never been recorded, and larger-than-expected threats in Cairns, Australia, and Tampa, Florida.

Grey swan tropical cyclones striking Tampa, Cairns and Dubai can generate storm surges of about 20 feet, 19 feet and 13 feet, respectively, with estimated annual exceedance probabilities of about 1/10,000. With climate change, these probabilities can increase significantly over the twenty-first century (to 1/3,100–1/1,100 in the middle and 1/2,500–1/700 towards the end of the century for Tampa).

20011120en1

Worse grey swan tropical cyclones, inducing surges exceeding 36 feet in Tampa and 23 feet in Dubai, are also revealed with non-negligible probabilities, especially towards the end of the century.

Posted in Earth Science, Extreme Weather | Tagged , ,

New Study Shows Deep Mantle Flow and Earthquakes

Earth is made up of a solid inner core, surrounded by a liquid outer core, in turn covered by a thicker or more viscous mantle, and ultimately by the solid crust beneath our feet.

*Interview with Professor Gary A Glatzmaier at bottom

earth-layers7_m

The magnetic field is generated by the motions of the liquid iron alloy in the outer core beneath Earth’s crust. These motions occur because the core is losing heat to the overlying solid mantle that extends up to the crust on which we live.

The mantle itself is also in motion. This mantle motion is responsible for the drifting of the continents at the surface – and also responsible for earthquakes, volcanoes, and temporal changes in the climate.

mantle_flow

In the past decade or so, researchers have focused on three possible mechanisms driving earthquakes. One is variations in gravitational potential energy, another is changes in thickness of the Earth’s crust along the Intermountain Belt and the third is changes in strength of the lithosphere; that is, the crust and upper mantle.

“In continental interiors, we know little about the forces that drive the earthquake cycle,” says Utah State University geophysicist Tony Lowry. “We rely mostly on the history of past earthquakes to assess hazards. But, because seismic observations cover only a tiny fraction of the time between the largest earthquakes, we can easily miss important parts of the story.”

earth_core_eq_trench_combo_m

Using new seismic and GPS data available from the massive NSF-funded Earthscope array across the western United States, the researchers looked at these observations simultaneously and found some surprises. “We’ve explored various aspects of how and why rocks break and flow, but this is the first time we’ve recognized the importance of deep mantle flow,” says Lowry. “This developing model gives us a new tool for understanding what makes earthquakes tick.”

____________________

Professor Gary A Glatzmaier – Solar Physicist – Gary’s recent research has focused on the Earth’s core. He produced the first dynamically-consistent computer simulations of the geo-dynamo, the mechanism in the Earth’s fluid outer core that maintains the geomagnetic field. The simulations span several millions of years, using an average numerical time step of 15 days. At the surface of the model Earth, the simulated magnetic field has an intensity, an axial dipole dominated structure, and a westward drift of the non-dipolar structure that are all similar to the Earth’s.
Website: http://www.es.ucsc.edu/~glatz/

AUDIO FILE HERE

 

 

Posted in Earth Science, Earthquakes | Tagged , , ,

New Horizons Locks Onto Next Target – Kuiper Belt

The New Horizons spacecraft completed its primary mission by making a flyby of the dwarf planet Pluto and taking extensive photographs and measurements about the little system and its collection of moons. It collected so much data, they will be downlinking the data into the Fall of 2016 – But like every NASA mission, the space agency likes to squeeze as much science as possible out of every gram of robot and drop of propellent.

kuiper-belt23

The extended mission has not yet been funded, but to be fuel-efficient the team needs to pick a target and adjust New Horizons’ trajectory now. 2014 MU69, nicknamed PT1 for Potential Target 1, is a tiny, dim world (magnitude 26.8) of an estimated 30 to 45 kilometers (19 to 28 miles) diameter, which is roughly the size of Pluto’s mid-sized moons Hydra and Nix and ten times larger than most comets.

By mass it’s 1,000 times larger than Rosetta’s Comet 67P/Churyumov–Gerasimenko and 1/10,000th the mass of Pluto. MU69 is easier to get to than the other lead contender, 2014 PN70, which means the team will have more flexibility to tweak the trajectory when closer to the object. But most importantly, it’s a totally different type of Kuiper Belt Object than Pluto is, giving us our first up-close look at a different type of object. New Horizons Principal Investigator Alan Stern gushes over the selection.

NewHorizons

“2014 MU69 is a great choice because it is just the kind of ancient KBO, formed where it orbits now, that the Decadal Survey desired us to fly by. Moreover, this KBO costs less fuel to reach [than other candidate targets], leaving more fuel for the flyby, for ancillary science, and greater fuel reserves to protect against the unforeseen”, says Stern.

New Horizons was originally designed to fly beyond the Pluto system and explore additional Kuiper Belt objects. The spacecraft carries extra hydrazine fuel for a KBO flyby; its communications system is designed to work from far beyond Pluto; its power system is designed to operate for many more years; and its scientific instruments were designed to operate in light levels much lower than it will experience during the 2014 MU69 flyby.

“Because we think that Kuiper Belt Objects haven’t been heated or changed much in the 4.6 billion year history of our Solar System, we’re optimistic that this little world will be a timecapsule into what the outer edges looked light while planets were busy colliding and accreting in the inner solar system.” New Horizons science team member John Spencer explains:

“There’s so much that we can learn from close-up spacecraft observations that we’ll never learn from Earth, as the Pluto flyby demonstrated so spectacularly. The detailed images and other data that New Horizons could obtain from a KBO flyby will revolutionize our understanding of the Kuiper Belt and KBOs.”

The New Horizons spacecraft will be making a series of burns in late October and early November to set it on a trajectory to encounter MU69. The closest approach is anticipated for January 1, 2019, although that may shift with later corrections.The closest approach of the flyby will when the object is nearly 6.5 billion kilometers (43.4 AU) from the Sun; we’re expecting that New Horizons will skim by the world even closer than it did to Pluto this summer.

We only discovered the world on June 26, 2014 as part of an intensive search for candidates for a New Horizons flyby. It’s so new to us that we aren’t even sure how long a year is for MU69! (We think it takes 293 Earth-years for it to make a single trip, but with a healthy margin of ±24 Earth-years error.) It also marks the shortest time between the discovery of a world and its exploration. Planetary astronomer Jason Cook teases that it’s downright rare for a discoverer to get to see their new worlds. More pragmatically, it’ll be interesting to see if the International Astronomical Union hustles to name it faster than its usual plodding process.

Along the way, New Horizons will be making opportunistic observations of any other Kuiper Belt Objects we can. Stern anticipates we might be able to see up to fifty other Kuiper Belt Objects. The observations will be simple – basic population characteristics, searching for binary objects, estimated sizes, and if we’re very lucky a few occultations of stars.

The extended mission to actually keep New Horizons operating with a human support team and time to send back data on the Deep Space Network isn’t actually approved yet. The science team will be writing and submitting a research proposal in 2016 for external review. John Grunsfeld, astronaut and chief of the NASA Science Mission Directorate, cautions:

Even as the New Horizon’s spacecraft speeds away from Pluto out into the Kuiper Belt, and the data from the exciting encounter with this new world is being streamed back to Earth, we are looking outward to the next destination for this intrepid explorer. While discussions whether to approve this extended mission will take place in the larger context of the planetary science portfolio, we expect it to be much less expensive than the prime mission while still providing new and exciting science.

Many space exploration missions do get extended missions – the Mars Opportunity rover’s primary mission ended after 90 days, and Cassini’s primary mission finished after four years back in 2008. However, if you want to help NASA get the political power of clear and loud public support, here’s how you can write to your Congressional representatives about approving the New Horizons extended mission.

After the flyby, the team hopes to keep New Horizons operating as it continues beyond the Kuiper Belt, following in the spirit of Voyager 1 and Voyager 2 as it discovers what lays beyond the edges of our Solar System.

Posted in Uncategorized | Tagged , ,

New Discovery Finds the Making of Gamma Ray Burst in Progress

Why is this important? Because the Earth has been hit by the surge of cosmic rays from a quasar (or supernova) at least 5 times in our historical past, and once in recent history during the year 774/775 AD (or CE). This event resulted in a stream of charged particles made up of cosmic rays and gamma radiation causing a “global” damage to Earth’s atmosphere.

gamma-ray-tree-rings

A new discovery by astronomers using NASA’s Hubble Space Telescope have found that Markarian 231 (Mrk 231), the nearest galaxy to Earth is powered by two central black holes furiously whirling about each other producing the inevitable result of a ‘gamma ray burst’.

Scientists looked at Hubble archival observations of ultraviolet radiation emitted from the center of Mrk 231 to discover what they describe as “extreme and surprising properties.” say Xinyu Dai of the University of Oklahoma.

binary_charged funnel_m

Gamma ray bursts are the most powerful explosions known in the universe. They can discharge as much energy as our Sun during its entire 10 billion year lifetime in anywhere from millisecond to a minute or more.

In March 2013, a similar finding was disclosed in the constellation Sagittarius with a forming gamma ray burst known as WR 104 which is even closer to Earth. What makes this a most distressing find, is the view of a nearly perfect spiral as viewed from Earth – “It could only appear like that if we are looking nearly exactly down on the axis of the binary system,” says Peter Tuthill, an astronomer at the University of Sydney.

gammarayburst55

“This is the first object that we know of that might release a gamma ray burst at us,” said astrophysicist Adrian Melott at the University of Kansas in Lawrence, who did not participate in this study. “And it’s close enough to do some damage.”

This binary system is about 8,000 light years away, roughly a quarter of the way to the center of the Milky Way Galaxy. While this might seem far away, research suggests a gamma ray burst with its funnel in-line with Earth would be devastating  with unknown consequences.

More interviews will be posted next…

This is a Free article. If you find it useful you can donate any amount you wish. This is a new service for ECM.

paypal_banner

Posted in Galaxy, Uncategorized | Tagged , , , , ,

CERN Finds New Hints of Lepton Particles

The Standard Model of particle physics, which explains most of the known behaviors and interactions of fundamental subatomic particles, has held up remarkably well over several decades. This far-reaching theory does have a few shortcomings, however–most notably that it doesn’t account for gravity.

lepton_particles

In hopes of revealing new, non-standard particles and forces, physicists have been on the hunt for conditions and behaviors that directly violate the Standard Model.

Now, a team of physicists working at CERN’s Large Hadron Collider (LHC) has found new hints of particles–leptons, to be more precise–being treated in strange ways not predicted by the Standard Model. The discovery, scheduled for publication in the September 4, 2015 issue of the journalPhysical Review Letters, could prove to be a significant lead in the search for non-standard phenomena.

The team, which includes physicists from the University of Maryland who made key contributions to the study, analyzed data collected by the LHCb detector during the first run of the LHC in 2011-12. The researchers looked at B meson decays, processes that produce lighter particles, including two types of leptons: the tau lepton and the muon. Unlike their stable lepton cousin, the electron, tau leptons and muons are highly unstable and quickly decay within a fraction of a second.

According to a Standard Model concept called “lepton universality,” which assumes that leptons are treated equally by all fundamental forces, the decay to the tau lepton and the muon should both happen at the same rate, once corrected for their mass difference. However, the team found a small, but notable, difference in the predicted rates of decay, suggesting that as-yet undiscovered forces or particles could be interfering in the process.

“The Standard Model says the world interacts with all leptons in the same way. There is a democracy there. But there is no guarantee that this will hold true if we discover new particles or new forces,” said study co-author and UMD team lead Hassan Jawahery, Distinguished University Professor of Physics and Gus T. Zorn Professor at UMD. “Lepton universality is truly enshrined in the Standard Model. If this universality is broken, we can say that we’ve found evidence for non-standard physics.”

The LHCb result adds to a previous lepton decay finding, from the BaBar experiment at the Stanford Linear Accelerator Center, which suggested a similar deviation from Standard Model predictions. (The UMD team has participated in the BaBar experiment since its inception in 1990’s.) While both experiments involved the decay of B mesons, electron collisions drove the BaBar experiment and higher-energy proton collisions drove the LHC experiment.

“The experiments were done in totally different environments, but they reflect the same physical model. This replication provides an important independent check on the observations,” explained study co-author Brian Hamilton, a physics research associate at UMD. “The added weight of two experiments is the key here. This suggests that it’s not just an instrumental effect–it’s pointing to real physics.”

“While these two results taken together are very promising, the observed phenomena won’t be considered a true violation of the Standard Model without further experiments to verify our observations,” said co-author Gregory Ciezarek, a physicist at the Dutch National Institute for Subatomic Physics (NIKHEF).

“We are planning a range of other measurements. The LHCb experiment is taking more data during the second run right now. We are working on upgrades to the LHCb detector within the next few years,” Jawahery said. “If this phenomenon is corroborated, we will have decades of work ahead. It could point theoretical physicists toward new ways to look at standard and non-standard physics.”

With the discovery of the Higgs boson–the last major missing piece of the Standard Model–during the first LHC run, physicists are now looking for phenomena that do not conform to Standard Model predictions. Jawahery and his colleagues are excited for the future, as the field moves into unknown territory.

“Any knowledge from here on helps us learn more about how the universe evolved to this point. For example, we know that dark matter and dark energy exist, but we don’t yet know what they are or how to explain them. Our result could be a part of that puzzle,” Jawahery said. “If we can demonstrate that there are missing particles and interactions beyond the Standard Model, it could help complete the picture.”

| Tagged , , , ,

Astrophysicists Find Supermassive Black Holes in Quasar Nearest Earth

Astronomers using NASA’s Hubble Space Telescope have found that Markarian 231 (Mrk 231), the nearest galaxy to Earth that hosts a quasar, is powered by two central black holes furiously whirling about each other.

mrk231_m

The finding suggests that quasars—the brilliant cores of active galaxies—may commonly host two central supermassive black holes that fall into orbit about one another as a result of the merger between two galaxies. Like a pair of whirling skaters, the black-hole duo generates tremendous amounts of energy that makes the core of the host galaxy outshine the glow of the galaxy’s population of billions of stars, which scientists then identify as quasars.

Scientists looked at Hubble archival observations of ultraviolet radiation emitted from the center of Mrk 231 to discover what they describe as “extreme and surprising properties.”

If only one black hole were present in the center of the quasar, the whole accretion disk made of surrounding hot gas would glow in ultraviolet rays. Instead, the ultraviolet glow of the dusty disk abruptly drops off towards the center. This provides observational evidence that the disk has a big donut hole encircling the central black hole. The best explanation for the observational data, based on dynamical models, is that the center of the disk is carved out by the action of two black holes orbiting each other. The second, smaller black hole orbits in the inner edge of the accretion disk, and has its own mini-disk with an ultraviolet glow.

“We are extremely excited about this finding because it not only shows the existence of a close binary black hole in Mrk 231, but also paves a new way to systematically search binary black holes via the nature of their ultraviolet light emission,” said Youjun Lu of the National Astronomical Observatories of China, Chinese Academy of Sciences.

“The structure of our universe, such as those giant galaxies and clusters of galaxies, grows by merging smaller systems into larger ones, and binary black holes are natural consequences of these mergers of galaxies,” added co-investigator Xinyu Dai of the University of Oklahoma.

The central black hole is estimated to be 150 million times the mass of our Sun, and the companion weighs in at 4 million solar masses. The dynamic duo completes an orbit around each other every 1.2 years.

The lower-mass black hole is the remnant of a smaller galaxy that merged with Mrk 231. Evidence of a recent merger comes from the host galaxy’s asymmetry, and the long tidal tails of young blue stars.

The result of the merger has been to make Mrk 231 an energetic starburst galaxy with a star-formation rate 100 times greater than that of our Milky Way galaxy. The infalling gas fuels the black hole “engine,” triggering outflows and gas turbulence that incites a firestorm of star birth.

The binary black holes are predicted to spiral together and collide within a few hundred thousand years.

Posted in Uncategorized | Tagged , , , , ,

Exploring the Limits of ‘Life’ in the Universe

Bizarre creatures that go years without water. Others that can survive the vacuum of open space. Some of the most unusual organisms found on Earth provide insights for Washington State University planetary scientist Dirk Schulze-Makuch to predict what life could be like elsewhere in the universe.

expo_planet3

NASA’s discovery last month of 500 new planets near the constellations Lyra and Cygnus, in the Milky Way Galaxy, touched off a storm of speculation about alien life. In a recent article in the journal Life, Schulze-Makuch draws upon what is known about Earth’s most extreme lifeforms and the environments of Mars and Titan, Saturn’s moon, to paint a clearer picture of what life on other planets could be like. His work was supported by the European Research Council.

“If you don’t explore the various options of what life may be like in the universe, you won’t know what to look for when you go out to find it,” said Schulze-Makuch, a professor in the WSU School of the Environment.

For example, on Earth, a species of beetle called bombardier excretes an explosive mix of hydrogen peroxide and other chemicals to ward off predators.“We do not propose that these organisms exist but like to point out that their existence would be consistent with physical and chemical laws, as well as biology,” he said.

harp

“On other planets, under gravity conditions similar to those present on Mars, a bombardier beetle-like alien could excrete a similar reaction to propel itself as much as 300 meters into the air,” Schulze-Makuch said.

While explorers to Mars might find creatures similar to those on Earth, life on a Titan-like planet would require a completely novel biochemistry. Such a discovery would be a landmark scientific achievement with profound implications.

Life on Mars

Earth life, with its unique biochemical toolset, could feasibly survive on a Mars-like planet with a few novel adaptations.

First, organisms would need a way to get water in an environment that is akin to a drier and much colder version of Chile’s Atacama Desert. A possible adaptation would be to use a water-hydrogen peroxide mixture rather than water as an intracellular liquid, Schulze-Makuch said.

Hydrogen peroxide is a natural antifreeze that would help microorganisms survive frigid Martian winters. It is also hygroscopic, meaning it naturally attracts water molecules from the atmosphere.

During the daytime, plant-like microorganisms on a Martian-like surface could photosynthesize hydrogen peroxide. At night, when the atmosphere is relatively humid, they could use their stored hydrogen peroxide to scavenge water from the atmosphere, similar to how microbial communities in the Atacama use the moisture that salt brine extracts from the air to stay alive.

Schulze-Makuch speculates that a larger, more complex alien creature, maybe resembling Earth’s bombardier beetle, could use these microorganisms as a source of food and water. To move from one isolated patch of life-sustaining microorganisms to another, it could use rocket propulsion.

Life on Titan

Due to its greater distance from the Sun, Titan is much colder than Earth. Its surface temperature is on average -290 degrees F. Additionally, there is no liquid water on the surface nor carbon dioxide in the atmosphere. The two chemical components are essential for life as we know it.

If life does exist on Titan or a Titan-like planet elsewhere in the universe, it uses something other than water as an intracellular liquid. One possibility is a liquid hydrocarbon like methane or ethane. Non-water based lifeforms could feasibly live in the liquid methane and ethane lakes and seas that make up a large portion of Titan’s surface, just as organisms on Earth live in water, Schulze-Makuch said.

Due to their frigid environment, these organisms would have huge (by Earth standards) and very slowly metabolizing cells. The slow rate of metabolism would mean evolution and aging would occur much slower than on Earth, possibly raising the life span of individual organisms significantly.Such hypothetical creatures would take in hydrogen in place of oxygen and react it with high energy acetylene in the atmosphere to produce methane instead of carbon dioxide.

“On Earth, we have only scratched the surface of the physiological options various organisms have. But what we do know is astounding,” Schulze-Makuch said. “The possibilities of life elsewhere in the universe are even more staggering.

“Only the discovery of extraterrestrial life and a second biosphere will allow us to test these hypotheses,” he said, “which would be one of the grandest achievements of our species.”

Posted in Uncategorized | Tagged , , ,