Earth ChangesS


Better Earth

Sounds Travel Farther Underwater As World's Oceans Become More Acidic

It is common knowledge that the world's oceans and atmosphere are warming as humans release more and more carbon dioxide into the Earth's atmosphere. However, fewer people realize that the chemistry of the oceans is also changing - seawater is becoming more acidic as carbon dioxide from the atmosphere dissolves in the oceans.

increasing carbon dioxide
© MBARI; Base image courtesy of David FiersteinThis illustration shows how increasing carbon dioxide in the atmosphere leads to an increase in the acidity of seawater, which in turn allows sounds (such as whale calls) to travel farther underwater.
According to a paper to be published this week by marine chemists at the Monterey Bay Aquarium Research Institute, these changes in ocean temperature and chemistry will have an unexpected side effect - sounds will travel farther underwater.

Conservative projections by the Intergovernmental Panel on Climate Change (IPCC) suggest that the chemistry of seawater could change by 0.3 pH units by 2050 (see below for background information on pH and ocean acidification). In the October 1, 2008 issue of Geophysical Research Letters, Keith Hester and his coauthors calculate that this change in ocean acidity would allow sounds to travel up to 70 percent farther underwater. This will increase the amount of background noise in the oceans and could affect the behavior of marine mammals.

Igloo

Ancient Arctic Ice Could Tell Us About Future Of Permafrost

Researchers have discovered the oldest known ice in North America, and that permafrost may be a significant touchstone when looking at global warming.

"Previously it had been thought that permafrost completely melted out of the interior of Yukon and Alaska about 120,000 years ago, when climate was warmer than today," said Duane Froese, an assistant professor in the Department of Earth and Atmospheric Science and lead author of the study.

Evil Rays

Powerful quake hits off New Zealand

A powerful earthquake with a 7.3 magnitude struck off New Zealand early Tuesday, the US Geological Survey said, but there were no early reports of casualties or significant damage.

Bizarro Earth

Floods, landslides kill 50 in Vietnam, Thailand

Flash floods and landslides have killed 50 people in Vietnam and Thailand, swept away thousands of homes and inundated farmland, official reports said on Sunday. In Vietnam, the death toll from typhoon Hagupit, which struck the Philippines and China earlier in the week, has jumped to 32 with another five people missing.

Thousands of homes were either washed away or destroyed by heavy rains and landslides in northern Vietnam, the government's storm and flood prevention committee said.

Hagupit, which means "lashing" in Filipino, killed at least eight people in the Philippines and three in China where it triggered a "once-in-a-century storm tide."

Target

2 strong quakes rock Philippine capital

Manila, Philippines - Two strong earthquakes rocked the Philippine capital and nearby provinces nearly simultaneously Saturday, but no damage or tsunami alerts were reported, a senior seismologist said.

Renato Solidum, director of the Philippine Institute of Volcanology and Seismology, said a "moderately strong" tremor struck late morning Saturday followed by a "stronger one" five minutes later.

Roses

UK: Give a bee a home

The threat of extinction for British bees has prompted gardeners across the country to build new hives.

Home Hives
©Unknown

The beekeepers of Coventry are huddled around one of their hives at Ryton Gardens, in Warwickshire, headquarters of the charity Garden Organic. Dressed a little like astronauts, in protective white suits and hoods, they carefully lift one bee-coated frame after another to inspect them.

You might expect a bee-friendly organic garden to be a meadow dotted with dandelions and daisies, but Ryton is a series of well-kept beds with a herb garden, a rose garden and all the other trappings of formal horticulture. "A garden doesn't have to be a mess of wild flowers to seduce bees," says Peter Spencer, of the Warwickshire Beekeepers' Association. "It can be as neat and stylish as you like, but it must be planted with certain flowers." This is an excellent time to plant bee-friendly perennials, rich in easily accessible nectar and pollen, and get them established before winter sets in.

Roses

US: University of Minnesota researchers hope to revitalize the honey bee



Smoking beehive
©Unknown
Michael Simone squeezes smoke on the top of a bee colony before removing the honeycomb frame. Simone hypothesizes that the smoke disrupts the bees' chemical cues, confusing them and diverting their attention from the intruder.

Disease, mites and Colony Collapse Disorder all are threats to honey bee colonies, and helped cause 35 percent of U.S. bee colonies to die last winter alone.

Entomology Professor Marla Spivak is trying to change the 20-year decline in honey bee populations.

Fish

No Oxygen In Eastern Mediterranean Bottom-water

Research from Utrecht University shows that there is an organic-rich bed of sediment in the floor of the Eastern Mediterranean. This bed formed over a period of about 4000 years under oxygen-free bottom-water conditions.

Image
©Netherlands Organization for Scientific Research
A sediment sample used for this research. The dark-green bed is organic-rich sediment from sapropel S1.

A wet climatic period was responsible for the phenomenon. According to climate scenarios, the climate may become wetter in this area, potentially giving rise again to a period of oxygen-free bottom-water.

Alternating organic-rich and organic-poor beds have been deposited on the floor of the Eastern Mediterranean. These deposits coincide with the alternation of wet and dry climatic periods. Researchers believe that the organic-rich beds, called sapropels, can originate in two ways:
More organisms live in the surface water because, for example, rivers introduce more nutrients. As a result, more organisms sink to the bottom when they die.

The organic material is better preserved. If dead organisms sink to an oxygen-free bottom, the organic material breaks down less well.

Crusader

'Chemical equator' protects Antarctica's clean air



Image
©Hamilton et al./AGU
An invisible barrier separates the carbon-monoxide-rich air of South-East Asia from the pristine air of the Southern Ocean

Scientists have discovered a "chemical equator" just north of Australia that divides polluted air from South-East Asia from the largely uncontaminated atmosphere of the Southern Ocean that surrounds Antarctica.

The discovery will help researchers create accurate simulations of how pollutants move in the atmosphere and assess their impact on climate.

Bizarro Earth

6.0 Magnitude Earthquake Jolts Southern Tibet

An earthquake measuring 6.0 on Richter Scale hit southwestern Tibet Thursday near the Nepal-Tibet border. The earthquake struck at 9:47 a.m. (0147 GMT), according to the U.S. Geological Survey.

There were no immediate reports of damage or casualties from the quake, which hit Zhongba county in Shigatse (Xigaze) prefecture. The epicenter of the quake lied 250 miles (400 kilometers) northwest of Katmandu, Nepal's capital.