Oceanography

Think global warming might change things a little? You haven't seen anything compared to 50 million years ago.

Though Antarctica is year-round one of the coldest places on Earth, and the continent's interior is the coldest place, with annual average land temperatures far below zero degrees Fahrenheit, during the Eocene epoch, 40-50 million years ago, there was a period with high concentrations of atmospheric CO2 and consequently a greenhouse climate.  


Google Earth Mystery Object? - Hardly!

What is it that you can see in this snapshot of Google Earth in the vicinity of Amsterdam Island?


If you think it's a special antenna for transmitting earthquake waves in the general direction of people that a Secret Government AgencyTM hates, or if you just know that it's a secret underwater base you are probably a conspiracy theorist.

If you think it's Atlantis you are probably some kind of new age hippie.

If you think it's an image artifact you are probably very good at image analysis.  But wrong.

How is nitrogen removed from the ocean? Some new findings may provide answers.

The debate centers on how nitrogen, one of the most important food sources for ocean life and a controller of atmospheric carbon dioxide, becomes converted to a form that can exit the ocean and return to the atmosphere where it is reused in the global nitrogen cycle. 

Researchers have argued over which of two nitrogen-removal mechanisms, denitrification and anammox, is most important in the oceans. The question is not just a scientific curiosity, but has real world applications because one mechanism contributes more greenhouse gases to the atmosphere than the other.


Speculation goes that part of the problem for the RMS Titanic, which set out on its maiden voyage 102 years ago today, was bad luck; an exceptional number of icebergs.

Not really, according to a new analysis. There are more icebergs now.

Previously it had been suggested that the seas which sank the famous cruise ship had an exceptional number of icebergs, caused by lunar or solar effects, but using data on iceberg locations dating back to 1913 – recorded to help prevent a repeat of the Titanic – they have shown that 1912 was a significant ice year but not extreme.

Some of the carbon, like the black soot and charcoal residue of fires, that finds its way into Earth's oceans stays there for thousands for years, and some of the black carbon breaks away and hitches a ride to the ocean floor on passing particles.

Virtually all black carbon results from combustion. Soot, the airborne version of black carbon, is a key element of smoke. Charcoal is another form of black carbon. Each form is produced naturally by wildfires, as well by industry and other human activities.


The deepest areas of the Baltic Sea have always had a low oxygen content. The inflow of fresh water is actually limited by low thresholds at the entrance to the Baltic Sea.

At the same time, there is a relatively fresh layer above the denser and saltier water in the deep layer of the sea.

This results in an effective stratification of the water column, which prevents the mixing of water masses necessary to transfer oxygen to the water at the bottom.


Six glaciers in West Antarctica are moving faster than they did 40 years ago.

The amount of ice draining collectively from those half-dozen glaciers increased by 77 percent from 1973 to 2013, causing global sea level to rise, according to new research. 


It is said that nothing dies of old age in the ocean, that everything gets
eaten and all that remains of anything is waste.

But that waste is pure gold to
oceanographer David Siegel, director of the Earth Research Institute at U.C. Santa
Barbara.

In a study of the ocean's role in the global carbon cycle, Siegel and his colleagues used those nuggets to their advantage. They incorporated the lifecycle of phytoplankton
and zooplankton — small, often microscopic animals at the bottom of the food chain —into a novel mechanistic model for assessing the global ocean carbon export. 


Research using satellite observations and ice thickness measurements gathered by NASA's Operation IceBridge is giving new insight into one of the processes causing Greenland's ice sheet to lose mass.

A team of scientists calculated the rate at which ice flows through Greenland's glaciers into the ocean, which gives a clearer picture of how glacier flow affects the Greenland Ice Sheet and shows that this dynamic process is dominated by a small number of glaciers.

Operation IceBridge has been measuring the thickness of many of Greenland's glaciers, which allowed researchers to make a more accurate calculation of ice discharge rates. Researchers calculated ice discharge rates for 178 Greenland glaciers more than one kilometer (0.62 miles) wide.


Temperature has been driving the fluctuating size of Peru's Quelccaya Ice Cap, not snowfall, according to a new analysis.  The Quelccaya Ice Cap is the largest ice mass in the tropics and sits 18,000 feet above sea level in the Peruvian Andes. The dramatic shrinkage of the tropical glacier in recent decades has made it a poster child for global climate change.

The findings support suspicions that tropical glaciers are shrinking because of a warming climate, and could help scientists to better understand the natural variability of past and modern climate and to refine models that predict tropical glaciers' response to future climate change.