Antarctic Melting Faster, Jacksonville still has no plan

[stephendare]

http://www.washingtonpost.com/wp-dyn/content/article/2008/01/13/AR2008011302753_pf.html

Escalating Ice Loss Found in Antarctica
Sheets Melting in an Area Once Thought to Be Unaffected by Global Warming

By Marc Kaufman
Washington Post Staff Writer
Monday, January 14, 2008; A01

Climatic changes appear to be destabilizing vast ice sheets of western Antarctica that had previously seemed relatively protected from global warming, researchers reported yesterday, raising the prospect of faster sea-level rise than current estimates.

While the overall loss is a tiny fraction of the miles-deep ice that covers much of Antarctica, scientists said the new finding is important because the continent holds about 90 percent of Earth's ice, and until now, large-scale ice loss there had been limited to the peninsula that juts out toward the tip of South America. In addition, researchers found that the rate of ice loss in the affected areas has accelerated over the past 10 years -- as it has on most glaciers and ice sheets around the world.

"Without doubt, Antarctica as a whole is now losing ice yearly, and each year it's losing more," said Eric Rignot, lead author of a paper published online in the journal Nature Geoscience.

The Antarctic ice sheet is shrinking despite land temperatures for the continent remaining essentially unchanged, except for the fast-warming peninsula.

The cause, Rignot said, may be changes in the flow of the warmer water of the Antarctic Circumpolar Current that circles much of the continent. Because of changed wind patterns and less-well-understood dynamics of the submerged current, its water is coming closer to land in some sectors and melting the edges of glaciers deep underwater.

"Something must be changing the ocean to trigger such changes," said Rignot, a senior scientist with NASA's Jet Propulsion Laboratory. "We believe it is related to global climate forcing."

Rignot said the tonnage of yearly ice loss in Antarctica is approaching that of Greenland, where ice sheets are known to be melting rapidly in some parts and where ancient glaciers have been in retreat. He said the change in Antarctica could become considerably more dramatic because the continent's western shelf, an expanse of ice and snow roughly the size of Texas, is largely below sea level and has broad and flat expanses of ice that could move quickly. Much of Greenland's ice flows through relatively narrow valleys in mountainous terrain, which slows its motion.

The new finding comes days after the head of the Intergovernmental Panel on Climate Change said the group's next report should look at the "frightening" possibility that ice sheets in Greenland and Antarctica could melt rapidly at the same time.

"Both Greenland and the West Antarctic ice sheet are huge bodies of ice and snow, which are sitting on land," said Rajendra Pachauri, chief of the IPCC, the United Nations' scientific advisory group. "If, through a process of melting, they collapse and are submerged in the sea, then we really are talking about sea-level rises of several meters." (A meter is about a yard.) Last year, the IPCC tentatively estimated that sea levels would rise by eight inches to two feet by the end of the century, assuming no melting in West Antarctica.

The new Antarctic ice findings are based on mapping of 85 percent of the continent over the past decade using radar data from European, Japanese and Canadian weather satellites. Previous studies had detected the beginning of ice loss in West Antarctica and substantial loss along the peninsula, but the current research found significantly greater changes.

Rignot and his team found that East Antarctica, which holds a majority of the continent's ice, has not experienced the same kind of loss -- probably because most of the ice sits atop land rather than below sea level, as in the west. In several coastal areas of East Antarctica, however, small but similar losses have been detected, he said.

In all, snowfall and ice loss in East Antarctica have about equaled out over the past 10 years, leaving that part of the continent unchanged in terms of total ice. But in West Antarctica, the ice loss has increased by 59 percent over the past decade to about 132 billion metric tons a year, while the yearly loss along the peninsula has increased by 140 percent to 60 billion metric tons. Because the ice being lost is generally near the bottom of glaciers, the glacier moves faster into the water and thins further, as a result. Rignot said there has been evidence of ice loss going back as far as 40 years.

The new findings come as the Arctic is losing ice at a dramatic rate and glaciers are in retreat across the planet. At a recent annual meeting of the American Geophysical Union, Ohio State University professor Lonnie Thompson delivered a keynote lecture that described a significant speed-up in the melting of high-altitude glaciers in tropical regions, including Peru, Tibet and Mount Kilimanjaro in Kenya.

Thompson, who has studied the Quelccaya glacier in the Peruvian Andes for 30 years, said that for the first half of that period, it retreated on average 20 feet per year. For the past 15 years, he said, it has retreated an average of nearly 200 feet per year.

"The information from Antarctica is consistent with what we are seeing in all other areas with glaciers -- a melting or retreat that is occurring faster than predicted," he said. "Glaciers, and especially the high-elevation tropical glaciers, are a real canary in the coal mine. They're telling us that major climatic changes are occurring."

While the phenomenon of ice loss worldwide is well documented, the dynamics in the Antarctic are probably the least understood. Glaciers and ice sheets are sometimes miles deep, and researchers do not know what might be happening at the bottom of the ice -- but it clearly is being lost along the peninsula and West Antarctic coast.

Rignot theorizes that the warmer water of the Antarctic Circumpolar Current is the cause. Douglas Martinson, a senior research scientist fellow at the Lamont-Doherty Earth Observatory of Columbia University, has studied the issue and agrees.

Martinson said the current, which flows about 200 yards below the frigid surface water, began to warm significantly in the 1980s, and that warming in turn caused wind patterns to change in ways that ultimately brought more warm water to shore. The result has been an increased erosion of the glaciers and ice sheets.

Martinson said researchers do not have enough data to say for certain that the process was set in motion by global warming, but "that is clearly the most logical answer."

Pachauri, the IPCC's chief of climate science, will visit Antarctica this week with Norwegian Prime Minister Jens Stoltenberg to get a firsthand view of the situation.

"You can read as much as you want on these subjects, but it doesn't really enter your system. You don't really appreciate the enormity of what you have," Pachauri said.

[RiversideGator]

All this ice loss, but the water levels look to be exactly the same to me at least in the St. Johns.   

[second_pancake]

I saw this on the news.  Pretty scary.

RG:  And we all know that by looking at something every single day means you notice every little change, right?  lol.  Btw, we wouldn't see water levels elevate to the point that it would affect us until it's too late.  The levels increase gradually.  It's not like the ocean is an 8oz cup of ice filled over the rim, where the melting ice causes a huge mess.  There is more water on the planet than land, so to have ice plates and ice bergs melting causes increases to the levels of water in minute measurements, that through time equate to feet which is devestating for places like FL that are below sea-level.  Anyway, the St. John's is used as a primary water source for residents in our area and beyond, so if we're sucking water out at the same rate that water is going in, there wouldn't be any change. 

But, if you truly want to see something with your naked eye, just take a trip down to Ponte Vedra Beach or Vilano Beach and watch the houses falling into the ocean. 

[Lunican]

RG's feet are dry so he's doing just fine thank you.

[gatorback]

But, if you truly want to see something with your naked eye, just take a trip down to Ponte Vedra Beach or Vilano Beach and watch the houses falling into the ocean. 

Some snaps please?

[Midway ®]

I have converted my house to an Ark, so either way I win. On the one hand, I have a home with a cool nautical motif if there is no flood, and on the other hand, I can fulfill a biblical prophecy should there be a flood. As it turns out, this is a no lose proposition, at least for me and the several animals I have collected.

[Midway ®]

All this ice loss, but the water levels look to be exactly the same to me at least in the St. Johns.   

The St. Johns River flows North, so its immune to level change from the ice melting in the ocean because its flowing away from Antartica, so thats why you don't see it going up.

[midnightblackrx]

in all seriousness guys, the ice is tired of the cold and is in search of warmer weather.   

[gatorback]

All this ice loss, but the water levels look to be exactly the same to me at least in the St. Johns.  

The St. Johns River flows North, so its immune to level change from the ice melting in the ocean because its flowing away from Antartica, so thats why you don't see it going up.

And what degree has been conferred to you to make That statement?  Are you a scientist or do you just have a friend over at the psyhic network?   Because, the last time I check the St. John's river has "tidal" flows.  And it's these "tidal" flows that raise and lower the level of the river itself.  Now unless, your psyhic friend sees something I don't, then I'm affraid your psyhic friend is wrong and you are wronger. 

[RiversideGator]

I saw this on the news.  Pretty scary.

RG:  And we all know that by looking at something every single day means you notice every little change, right?  lol.  Btw, we wouldn't see water levels elevate to the point that it would affect us until it's too late.  The levels increase gradually. 

No kidding.  Sea level changes are gradual??  Perhaps y'all are unable to detect sarcasm even with the  icon following my post.

The point is sea level changes are very gradual and probably not caused by man.  Here is a chart of sea level changes from 1900 to 2003 at various US points:



A rise of 250 millimeters (9.84 inches) over 100 years is not something I am going to lose sleep over.  And, we are coming off a glacial period so a rise in sea levels is not particularly surprising.  See this chart for changes over the last 9,000 years:

But, if you truly want to see something with your naked eye, just take a trip down to Ponte Vedra Beach or Vilano Beach and watch the houses falling into the ocean.

You do understand the difference between a sea level rise and coastal erosion, dont you?  Since it is apparent that you do not, I would suggest you read this:

Coastal erosion (see also beach evolution) is the wearing away of land or the removal of beach or dune sediments by wave action, tidal currents, wave currents, or drainage. Waves, generated by storms or fast moving motor craft, cause coastal erosion, which may take the form of long-term losses of sediment and rocks, or merely in the temporary redistribution of coastal sediments; erosion in one location may result in accretion nearby. The study of erosion and sediment redistribution is called 'coastal morphodynamics'. It may also be caused by hydraulic action, abrasion, and corrosion.

http://en.wikipedia.org/wiki/Coastal_erosion

[RiversideGator]

All this ice loss, but the water levels look to be exactly the same to me at least in the St. Johns.   

The St. Johns River flows North, so its immune to level change from the ice melting in the ocean because its flowing away from Antartica, so thats why you don't see it going up.

The St Johns River is heavily influenced by sea level and tides.  Just wait till the next hurricane comes through with a storm surge up the mouth of the River for confirmation of this.  Still, this Gorean sea level rise has caused no problems for coastal Jacksonville.  Maybe if we wait around for 500 years we will start to notice some problems.   

[Midway ®]

How do you know what the sea level was 9000 years ago? Were you there? Did you see it? And besides, the earth is only 6000 years old anyway.

[Ocklawaha]

When I read these posts I had a fesh glass full of ice and tea. When the Ice melted the glass wasn't nearly as full as when I sat it there... Wouldn't the North Pole effect be the same since Ice contains o2 ? Water expands as it freezes, so it follows that it contracts as it thaws. So could Florida GROW?

Now I haven't made a study of this, and certainly the South Pole is on land and mountains, but is one more land of seasons and flowing rivers REALLY going to drown Jacksonville? My guess is, if it is, our problems are going to be much bigger then just water worrys. It would be the end of the World as we know it.

Ocklawaha

[Ocklawaha]

Thanks Stephendare, you know the old hippie syndrome...

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ


Ocklawaha

[RiversideGator]

When I read these posts I had a fesh glass full of ice and tea. When the Ice melted the glass wasn't nearly as full as when I sat it there... Wouldn't the North Pole effect be the same since Ice contains o2 ? Water expands as it freezes, so it follows that it contracts as it thaws. So could Florida GROW?

Now I haven't made a study of this, and certainly the South Pole is on land and mountains, but is one more land of seasons and flowing rivers REALLY going to drown Jacksonville? My guess is, if it is, our problems are going to be much bigger then just water worrys. It would be the end of the World as we know it.

Welcome to the ball game, Ock.

Late, but welcome all the same.

and no. there is no chance of the sand bar that we live on growing.  Only 500 years ago it was all underwater, and that was with a minor difference in sea levels.

What is being discussed is a twenty foot rise from the antarctic alone.  If Greenland melts, add another 20 feet to that.

Florida was under water 500 years ago??  This might come as a surprise to the Spanish who first set foot on Florida soil 495 years ago in 1513 and to the Indians who inhabited the peninsula for at least the 13,000 years before that.
http://en.wikipedia.org/wiki/History_of_Florida

BTW, I think Florida was underwater perhaps 30,000 years ago.
http://www.keyshistory.org/keysgeology.html

Thanks for the insight though Professor Dare.