Earth ChangesS


Last chance for Tuna - Tagging the tigers of the sea

Pablo Cermeño balances at the back of the small boat, legs braced, harpoon at the ready. Beneath him in the crystal waters his target is clearly visible: a shimmer of metallic turquoise that tacks left, right, left again as it is hauled inexorably towards the surface. The fisherman grunts and sweats as he does battle with the giant fish, reeling, pulling and reeling again.

Better Earth

Are Our Oceans Made of Extraterrestrial Material?

© Michele HoganPacific ocean.
Contrary to preconceived notions, the atmosphere and the oceans were perhaps not formed from vapors emitted during intense volcanism at the dawning of our planet. Francis Albarède of the Laboratoire des Sciences de la Terre (CNRS / ENS Lyon / Université Claude Bernard) suggests that water was not part of the Earth's initial inventory but stems from the turbulence caused in the outer Solar System by giant planets. Ice-covered asteroids thus reached the Earth around one hundred million years after the birth of the planets.

The Earth's water could therefore be extraterrestrial, have arrived late in its accretion history, and its presence could have facilitated plate tectonics even before life appeared. The conclusions of the study carried out by Albarède feature in an article published on the 29 October 2009 in the journal Nature.

Space agencies have got the message: wherever there is life there has to be water. Around 4.5 billion years ago, the Earth was bequeathed with sufficient water for oceans to form and for life to find favorable niches in the seas and on the continents resulting from plate tectonics. In comparison, the Moon and Mercury are dry, mortally cold deserts, Mars dried up very quickly and the surface of Venus is a burning inferno.

Bizarro Earth

5.6 Earthquake Hits Mindanao, Philippines

A moderate earthquake measuring 5.6 on the Richter scale occurred in Mindanao, the Philippines at 9.48pm on Wednesday night.

The Malaysian Meteorological Department said in a statement that the quake's epicentre was located 231km southeast of Cebu, the Philippines and 934km northeast of Sandakan, Sabah.

However, the earthquake did not pose any tsunami threat.


Elephant Seals Sleep While Diving, Study Suggests

© Karen SeagleA pair of elephant seals takes an afternoon snooze on the beach near San Simon, California
Migrating northern elephant seals slowly drift downward to rest in the ocean depths, according to a new study of the animals' dive patterns.

Moving from their breeding colonies in California to their wintering areas in the mid-Pacific and around Alaska, the seals spend two to eight months at sea without a single pit stop.

There's no land to climb on along the roughly 2,000- to 3,000-mile (3,200- to 4,800-kilometer) voyage, and the seabed is often miles below the surface.

The marine mammals' grueling trek had many researchers wondering: When and how do elephant seals sleep?

It's long been known that, during the seals' epic migrations, the animals engage in repetitive dives down to depths of 984 feet (300 meters) or more.

Now a study of young elephant seals has revealed that during some of these dives, elephant seals roll on their backs and allow themselves to sink.


Hurricane Ida Kills 152 in El Salvador

© RIA Novosti
The death toll from mudslides and flooding in El Salvador caused by hurricane Ida has risen to 152 with many more missing, national media quoted rescuers as saying on Wednesday.

Over 13,000 people were left homeless as mudslides destroyed about 2,000 houses in the small Central American country, amid torrential rains triggered by the hurricane.

The mayor of San Vicente, Medadro Hernandez Lara, said that around 500 people are missing.

Addressing an extraordinary Cabinet meeting on Monday, President Mauricio Funes described the damage inflicted by the hurricane as "uncountable." He also said that $150 million will be allocated for cleanup and rescue operations.

International humanitarian packages have started arriving in the country. Venezuela has sent a planeload of food, while Guatemala and Nicaragua have provided relief workers and rescue equipment. The United States has channeled $100,000 into the construction of temporary housing.

Bizarro Earth

Blizzard Hits North China, Paralyzes Major Cities

© ShanghaiDailyA man walks on a snow-covered street in Shijiazhuang, capital of north China's Hebei Province, today.
Heavy snow blanketed Shijiazhuang, capital of north China's Hebei Province, for a second day today and paralyzed all transport, including aviation and highway services, provincial authorities said today.

Meteorological officials said city recorded 74 mm of snow in the 24 hours till 6 am today, with the accumulated snow 48 mm thick in most areas.

It was the heaviest snow fall in the city since 1955 when the city began to make meteorological records.

Xinhua reporters saw no traffic on roads in the city, and pedestrians struggled through knee-high snow. All middle and primary schools were informed they could suspend classes if necessary.

All flights from and to the city have been canceled, and all local sections of the six expressways traversing the city, including the Beijing-Shijiazhuang, Zhangjiakou-Shijiazhuang,Shijiangzhuang-Huanghua, and Qingdao-Yinchuan expressways were closed, said transport authorities.


Philippines: Mayon Volcano Erupts

More ash explosions seen

The Philippine Institute of Volcanology and Seismology recorded an ash explosion in Mayon Volcano early Wednesday, which caused ash fall in Albay towns located southwest and northwest of the volcano.

"The explosion, which occurred at around 1:58 a.m., is a clear sign of magma intrusion toward the summit crater of the volcano," said Alex Baloloy, Phivolcs science research analyst.

The explosion, which lasted for about three minutes, was accompanied by rumbling sounds. Residents in the towns of Camalig, Guinobatan, Polangui, Oas, and Ligao City reported experiencing the ash fall.

Baloloy said, however, that the height of the ash column was not recorded because clouds covered the view of the volcano and it was still dark when the explosion happened.

Arrow Down

Koalas Face Extinction Within 30 years

Australia's koalas could be become extinct within 30 years unless urgent action is taken to halt a decline in the population, researchers say.

Development, climate change and bushfires have all contributed in reducing the numbers of wild koalas. The sexually transmitted disease chlamydia has also played a part in the animal's demise. In the past six years alone the population may have dropped by half according to a survey carried out by the Australian Koala Foundation.

Previous estimates put the number of koalas at more than 100,000. However recent estimates show there may be as few as 43,000. The foundation collected field data from 1,800 sites and 80,000 trees to calculate the numbers. In one area in northern Queensland estimated to have 20,000 koalas a decade ago, a team of eight people could not find a single animal in four days of searching.

Bizarro Earth

5.0 Earthquake Hits Western Indonesia

An earthquake measuring 5.0 on the Richter scale rocked West Sumatra province in the western parts of Indonesia on Wednesday, the Meteorology and Geophysics Agency said.

The quake occurred at 10:14 a.m. Jakarta time (0314 GMT) with the epicenter at 69 km southeast of Siberut of Mentawai island of the province and at a depth of 15 km, the agency said.

Indonesia has been conducting reconstruction in the province after the 7.6 magnitude quake on Sept. 30 killed more than 1,000 people.


New Fossil Plant Discovery Links Patagonia to New Guinea in a Warmer Past

Foliage of Papuacedrus prechilensis
© P. Wilf.The monotypic genus Papuacedrus is today restricted to montane rainforests of New Guinea and the Moluccas, but its scarce fossil record includes Tasmania and Antarctica.
How revising an ancient species can change what we know of a lineage's historical distribution and the climate in which it lived

Fossil plants are windows to the past, providing us with clues as to what our planet looked like millions of years ago. Not only do fossils tell us which species were present before human-recorded history, but they can provide information about the climate and how and when lineages may have dispersed around the world. Identifying fossil plants can be tricky, however, when plant organs fail to be preserved or when only a few sparse parts can be found.

In the November issue of the American Journal of Botany, Peter Wilf (of Pennsylvania State University) and his U.S. and Argentine colleagues published their recent discovery of abundant fossilized specimens of a conifer previously known as "Libocedrus" prechilensis found in Argentinean Patagonia. This plant was first described in 1938 based on one fossil vegetative branch whose characteristics were said to most closely match those of a living South American dry, cold-climate conifer found in the study area: Austrocedrus (Libocedrus) chilensis, the Cordilleran Cypress.

However, numerous characteristics of the leaves, including their distinctive shape and stomatal arrangements, as well as seed cone details of the newly discovered specimens entirely match those of extant Papuacedrus, a closely related genus, currently found only in tropical, montane New Guinea and the Moluccas.