Greenland climate during the last ice age was very unstable, the researchers say, characterized by a number of large, abrupt changes in mean annual temperature that each occurred within several decades. These so-called "Dansgaard-Oeschger events" took place every few thousand years during the last ice age. Temperature changes in Antarctica showed an opposite pattern, with Antarctica cooling when Greenland was warm, and vice versa.

The ocean sucks up heat-trapping carbon dioxide (CO2) building up in our atmosphere with help from tiny plankton.

Like plants on land, plankton convert CO2 into organic carbon via photosynthesis and then can sink into the deep ocean, carrying carbon with them. They decompose when bacteria convert their remains back into CO2.

This "biological pump," if it operated 100 percent efficiently, would mean nearly every atom of carbon drawn into the ocean would be converted to organic carbon, sink into the deep ocean, and remain sequestered from the atmosphere for millennia. But like hail stones that melt before reaching the ground, some carbon never makes it to the deep ocean, allowing CO2 to leak back into the upper ocean and ultimately exchange with the atmosphere.

We are still trying to fully understand the extent of the damage caused by the Deepwater Horizon oil spill five years ago, one of the worst environmental disasters in US history.

Though some studies have linked icebergs to abrupt climate change cycles during the last glacial period - by introducing fresh water to the surface of the ocean and changing ocean currents, which changes climate - new findings present a contradictory narrative and suggest that icebergs generally arrived too late to trigger marked cooling across the North Atlantic.

Abrupt climate change, characterized by transitions between warm and cold conditions across the North Atlantic, is a pervasive feature of the Late Pleistocene - the most recent period of repeated glacial cycles. 

The one common element in recent American weather has been its diversity. The West Coast has been drier than usual while the East Coast has had more snow. Fish are swimming into new waters and so hungry seals that don't follow them aare washing up on California beaches. 

A long-lived patch of warm water off the West Coast, about 1 to 4 degrees Celsius (2 to 7 degrees Fahrenheit) above normal, is part of what's wreaking much of this mayhem, according to two papers Geophysical Research Letters. No, that warm blob was not caused by climate change, though it has many of the same effects for West Coast weather. 

Methane is a greenhouse gas with more warming impact than carbon dioxide but also fortunately a much shorter life in the atmosphere.

Due to the popularity of much cleaner natural gas, which has caused CO2 emissions to drop, there are concerns about methane but the big source is nature herself - decomposition of organic material, a complex process involving bacteria and microbes, is a big culprit.

A new study demonstrates for the first time how elemental carbon became an important construction material of some forms of ocean life after one of the greatest mass extinctions in the history of Earth more than 252 million years ago. 

As the Permian Period of the Paleozoic Era ended and the Triassic Period of the Mesozoic Era began, more than 90 percent of terrestrial and marine species became extinct.

Various proposals have been suggested for this extinction event, including extensive volcanic activity, global heating, or even one or more extraterrestrial impacts.

Crocus and daffodil blossoms mean spring has arrived on land and a similar "greening" event, a massive phytoplankton bloom, unfolds each spring in the Atlantic Ocean.

But, what happens to all that organic material produced in the surface ocean? 

The ocean is a huge reservoir of dissolved organic molecules, many of them stable against microbial utilization for hundreds and even thousands of years.  They contain a similar amount of carbon as compared to carbon dioxide (CO2) in the atmosphere and the origin of these persistent molecules has been something of an enigma.

Though the developed world is concerned about greenhouse gas emissions implicated in climate change and global warming, reactions in nature have been less consistent.

Polar bears have been increasingly forced on shore due to sea ice loss, where they eat berries, birds and eggs, while ice seals, the usual lipid-rich prey of bears, couldn't be happier that thinner ice has made them harder to get to.