Earthquakes

Magnitude 5+ Earthquakes – Global

5.2 Earthquake hits Mindanao in the Philippines.

Global Warming

727 People on Chesapeake Bay Island Could Become America’s First ‘Climate Refugees'

The Chesapeake Bay's Tangier Island, the site of the town of Tangier (population 727), will become uninhabitable under a midrange estimate of sea level rise due to climate change by 2063, researchers report in the Dec. 10 issue of the journal Scientific Reports.

Already, more than 500 lower-level islands in the Chesapeake Bay have vanished since Europeans first arrived in the area in the 1600s, said study leader David Schulte, an oceanographer with the U.S. Army Corps of Engineers Norfolk District. Engineering efforts could shore up Tangier, but saving the island and its neighbours will ultimately require action on climate.

Tangier is one of the Tangier Islands, a series of grassy spits of land about 14 miles (22 kilometers) east of mainland Virginia, within the Chesapeake Bay. Tangier is the southernmost of the islands, which also include Goose Island, Uppards Island and Port Isobel.

Thirty-nine islands in the Chesapeake Bay were once habitable, Schulte said. Today, Tangier and Smith Island in Maryland are the only two that remain so. Erosion and sea level rise (and, to some extent, other factors like land subsidence due to groundwater pumping) have eaten away at the rest.

Melting glaciers blamed for subtle slowing of Earth’s rotation

The melting of glaciers caused by the world’s rising temperatures appears to be causing a slight slowing of the Earth’s rotation in another illustration of the far-reaching impact of global climate change, scientists said on Friday.

The driving force behind the modest but discernible changes in the Earth’s rotation measured by satellites and astronomical methods is a global sea level rise fuelled by an influx of meltwater into the oceans from glaciers, the researchers said.

“Because glaciers are at high latitudes, when they melt they redistribute water from these high latitudes towards lower latitudes, and like a figure skater who moves his or her arms away from their body, this acts to slow the rotation rate of the Earth,” Harvard University geophysicist Jerry Mitrovica said.

The movement of ice and meltwater is also causing a slight migration of the Earth’s axis, or north pole, in a phenomenon known as “polar wander.

“These are small effects,” but are another indication of the profound impact of human-induced climate change on the planet, Mitrovica said. The observed rotation slowdown does not pose a danger to the planet.

Environment

Earth: Magnetic Flip

NASA has found evidence that the Earth's magnetic fields have weakened significantly in the past 160 years and this could cause a magnetic pole shift that could cause catastrophic effects on humanity.

The weakening of the magnetic fields was prompted by a gradual reverse re-alignment of iron atoms in the Earth's liquid outer core. Researchers at NASA's Mars Atmosphere and Volatile Evolution (MAVEN) have indicated that the magnetic flip could happen in as early as 100 years and as long as 1,000 years.

Should this phenomenon happen, compasses pointing to the north could flip to the south but more than this, magnetic flips are feared because it was reportedly the cause of mass extinctions in the past.

According to the report, the Earth will be rendered defenseless against direct exposure to solar radiation, solar flares and coronal mass ejections (CMEs) as magnetic fields act as the planet's shield against these.

"When the polar shift happens, the Earth will have no magnetic field for about 200 years," NASA MAVEN's principal investigator Bruce Jakosky said.

However, Niemegk Geomagnetic Observatory at GFZ Potsdam's Monika Korte explained that the magnetic flip is a gradual process.

"It's not a sudden flip, but a slow process, during which the field strength becomes weak, very probably the field becomes more complex and might show more than two poles for a while, and then builds up in strength and [aligns] in the opposite direction."

According to scientists, this will not be the first time the Earth will experience a magnetic flip as it happened around 780,000 years ago and again during the Ice Age some 41,000 years ago.

Earthquakes

Magnitude 5+ Earthquakes – Global

6.2 Earthquake hits southern Xinjiang, China.

A strong earthquake hit a rural part of China's far western Xinjiang region on Friday, killing at least six people, injuring dozens and destroying or damaging thousands of homes, the government and state media said.

6.0 Earthquake hits the Philippine Islands.

5.8 Earthquake hits the Andaman Islands off India.

5.3 Earthquake hits eastern New Guinea, Papua New Guinea.

5.2 Earthquake hits the Kermedec Islands.

5.1 Earthquake hits southern Xinjiang, China.

5.0 Earthquake hits south of the Kermedec Islands.

Space Events

Asteroid

The chunk of space rock, about 50 metres wide, will give us such a near miss that it will skim our planet inside the geosynchronous orbits of many TV and communications satellites on 15 February.

And despite its small size, it will become visible to amateur astronomers in binoculars and small telescopes, with its rapid motion across the starry background, covering an area of sky greater than the apparent width of the Moon every minute, being quite obvious.

 

The asteroid, which was discovered last year, is labelled 2012 DA14 and is known as a Near-Earth Object because its orbit makes it a potential impact threat at some time in its history. Fortunately, it will not hit us this time or at any date in the predictable future.

Although the asteroid is small, if it were on a collision course with Earth, it would produce the equivalent of 2.5 megatons of TNT.

In December, a larger 5 km-wide asteroid called Toutatis sped by us at a distance of 7 million km and was imaged by Chaina's Chang'e 2 space probe and by radar by radio telescopes on Earth.

Asteroids

There are presently 1322 potentially hazardous asteroids that can come closer to Earth than 0.05 AU. Potentially Hazardous Asteroids (PHAs) are pieces of space rock generally larger than approximately 100m in diameter. None of the known PHAs is on a collision course with the Earth, although astronomers are finding new ones all the time.