Posts tagged oceans.

kateoplis:

Bay of Biscay’s blooming Phytoplankton

  05/17/13 at 06:20pm via Flickr / gsfc

A primer on ocean acidification. What it is. How it works. And its impacts on the ocean. From the Arctic Monitoring and Assessment Programme.

AMAP is one of five Working Groups of the Arctic Council.

The primary function of AMAP is to advise the governments of the eight Arctic countries (Canada, Denmark/Greenland, Finland, Iceland, Norway, Russia, Sweden and the United States) on matters relating to threats to the Arctic region from pollution, and associated issues.

  05/12/13 at 10:21am

dendroica:

As predicted by chemistry, change in the Arctic Ocean is accelerating as temperatures warm faster than the global average, as the sea ice melts, as northern rivers run stronger and faster, delivering more fresh water farther into the northernmost ocean, and as we continue blasting an ever increasing quantity of greenhouse gases into the atmosphere.

The Arctic Ocean Acidification Assessment, a new report from the Arctic Monitoring and Assessment Program (AMAP), presents these 10 key findings:

10 Key Findings From a Rapidly Acidifying Arctic Ocean | Mother Jones

  05/08/13 at 07:41am via Mother Jones

Arctic Ocean 'acidifying rapidly' ›

Scientists estimate that the average acidity of surface ocean waters worldwide is now about 30% higher than before the Industrial Revolution.

The researchers say there is likely to be major change to the Arctic marine ecosystem as a result. Some key prey species like sea butterflies may be harmed. Other species may thrive. Adult fish look likely to be fairly resilient but the development of fish eggs might be harmed.

  05/07/13 at 12:40pm

colchrishadfield:

A heraldic Spring dragon of ice roars rampant off the coast of Newfoundland.

This is Astronaut Chris Hadfield’s newest shot from the space station. Melting ice caught in currents on the ocean off the coast of Newfoundland.

Trailer for Chasing Ice, an insane enviromentary that has swept-up dozens of awards. Scientists risk their lives over three-years to record the death of several of the world’s last remaining glaciers. Our glaciers are melting, disappearing faster than thought possible, and all due to a warming earth.

  05/03/13 at 11:16am

The Artic’s Shrinking Ice Cover

Sea ice is any form of ice found at sea that originated from the freezing of sea water. It is the most visible feature of the Arctic Ocean, with its extent waxing and waning with the seasons. Ice thickness is highly variable, ranging from a thin veneer to tens of meters. While the existence of sea ice reflects the cold conditions inherent to high latitudes, sea ice also strongly modulates the energy budget and climate of the Arctic and beyond, particularly because it is white, and hence reflects much of the sun’s energy back to space (it has a high albedo) and also through acting as a lid, insulating the underlying ocean from a generally much colder atmosphere.

Historically, at its maximum extent in March, Arctic sea ice covered an area more than 15 million square kilometers, somewhat less than twice the size of the contiguous United States. The minimum extent, occurring in September, the end of the melt season, was typically around 7.0 x106 km2. However, as assessed over the modern satellite record spanning 1979 to the present, Arctic sea ice extent exhibits downward linear trends for all months, weakest in winter and strongest for September. The downward September trend appears to have accelerated over the past decade. Through 2001, the September trend stood at -7.0% per decade. Through 2012, it was more than twice as large at -14.3% per decade. The six lowest September extents in the satellite record have all occurred in the past six years, with September of 2012 setting a new low mark. Decreased summer ice extent has been accompanied by large reductions in winter ice thicknesses that are primarily explained by changes in the ocean’s coverage of thick multiyear ice (MYI). MYI is ice that has survived at least one summer melt season. In the mid-1980s, MYI accounted for 70% of total winter ice extent, whereas by the end of 2012 it had dropped to less than 20%. At the same time the proportion of ice older than 5 years declined from 50% of the MYI pack to less than 8%.

Ice loss is also contributing to strong rises in Arctic air temperature during autumn and winter, not just at the surface, but extending through a considerable depth of the atmosphere. As discussed, sea ice acts as a lid, insulating the underlying ocean from a generally much colder atmosphere. With less ice, the insulating effect is weaker, so heat can readily be transferred from the ocean to the atmosphere above. This strong warming, termed Arctic amplification, is starting to extend beyond areas of ice loss to influence Arctic land areas.

Continued loss of the ice cover is in turn likely to impact on patterns of atmospheric circulation and precipitation not just within the Arctic, but into middle latitudes; there is evidence that this is already occurring. The basic reason for this is that the outsized warming of the Arctic changes the atmospheric stability and temperature differences between the Arctic and lower latitudes. Finally, as the ice cover retreats, the Arctic is becoming more accessible for marine shipping as well as oil and natural gas exploration, increasing the economic and strategic importance of the region.

  04/28/13 at 10:18am

We’re looking into how changes in ocean currents (e.g., thermohaline circulation) could impact existing oil pipelines on the ocean floor. The concern is that untrenched (exposed) lines and subsea systems (see engineering image, above) are underprepared for future turbulence, among other things.

The above “pipelay” ships are designed for one task - to weld and deliver various sized pipes onto the ocean floor. Most pipelines are connected to a series of special drills and platforms (see second image above) and are located in shallow water. And many lines are buried under the seabed by special trench digger robots (funtrue!). But some lines are in very deep oceans, and currents could be messing with their stability due to shifting ocean currents. 

As I was researching and answering reader mail (hello AK!), I got sidetracked to how some recent lines were originally designed and built. There are only a few specialized ships that handle the deepwater lines, so those are what I’m most interested in.

The first ship, above, is called the Solitaire. It’s massive. Built in 1998, and at 980 feet long(!), it’s among the largest pipelay ships on the planet! It’s also one of the most productive.

Here’s a video of how how Solitaire works! The first couple of minutes is an animated overview of the process. The next segment is live coverage of the inner workings. You can see workers, machines, and robots weld and piece the pipes together. The pipe is welded and ‘fed’ onto a spool that delivers the pipe onto the floor. It is amazing to see how flexible these pipes are. Really amazing stuff.

Do you want to read about these ships? If so, click here (careful, it is a huge, browser crushing PDF). It’s a poster describing 60 different pipely ships. It describes their owners, capacities, lay methods, and depths.

Yep, this is how I’m spending my Saturday night…

  04/27/13 at 11:29pm

Women climate scientists conquer Antarctica ›

Excellent read!

  04/27/13 at 03:52pm

foreignaffairsmagazine:

Gallery: Choking on China

China’s pollution problem in photos

Sea level rise causes salt water to mix with fresh water inland, creating a toxic saline that kills trees, destroys aquifers, and corrodes soils. These banana trees died from salt water inundation.

From the excellent slide show on climate impacts on Kiribati islands:

Kiribati enters the end game against climate change - in pictures

Father Martin, parish priest on the island of Abaiang walks through the wasteland that used to be the village of Tebunginako garden. Rising sea water made the soils heavily saline and unable to support the Bananas and Taro vital to the villagers’ survival

  04/16/13 at 09:09am

‘Citizen archaeologists’ needed for Orkney’s eroding coastal heritage

archaeologicalnews:

image

If you enjoy the coast, know about your local heritage – or want to explore it further, you could make a real contribution to a national project which is being run by The SCAPE Trust and the University of St Andrews.

The Scotland’s Coastal Heritage at Risk project is looking for volunteers who can visit threatened coastal archaeological and historical sites in their local areas to take photographs, record their current condition and contribute information to a national database of coastal archaeological sites.

Of the 1,000 archaeological sites around Scotland short-listed as the highest priority for action because of their importance and risk of loss as a result of erosion, nearly a quarter are in Orkney. Read more.

Would love to be in Scotland to help out.

watershedplus:

The FLoating Instrument Platform (FLIP) is a naval research station designed in 1962. It is towed horizontally to open water then flips vertically to provide a stable platform mostly immune to wave action.

The tilting is actioned by directing water into ballast tanks. The position is reversed by sending compressed air in the tanks. Because the bulkhead becomes the deck, FLIP has rooms with doors mounted on the floor, portholes in the ceiling, and sinks and toilets mounted for both configurations.

Developed during the cold war, it continues to provide a uniquely stable platform for research missions that include ocean acoustics, marine mammal studies, geophysics, meteorology, physical oceanography, and laser propagation experiments.

Read more here and here.

  03/31/13 at 10:04am via watershedplus

roomthily:

ice fractures on the Beaufort Sea

via Earth Observatory

timzimmermann:

Those Crazy Plastic Cleaning Machines”: Pushback on oceanic vacuums.

View Post

Yesterday, I wrote a few reasons why this project is not feasible. Legal protections for marine species and moral hazard are two obvious examples. Above, Zimmerman rounds up a few of the more sophisticated criticisms of the project.

  03/28/13 at 11:43pm via timzimmermann