First came "The Day After" which was the movie in which WWIII came so everyone wound up radioactive and died. Not a single politician of note except for Bernie Sanders gave a moment's credence to the collective wisdom of the world scientists which was inherent in the movie.
"The Day After Tomorrow" came after "The Day After" as is Hollywood's wont to do and in this one the new Ice Age came because of disturbance of the circulation of the global ocean currents.
The current research doesn't forecast anything so extreme but they do know the deep water circulation of the ocean is changing. (Science Daily: Antarctic bottom waters freshening at unexpected rate)
In some places along the Antarctic coast, ice formation causes seawater to grow saltier and therefore denser, so that it sinks to the sea floor. Known as the Antarctic Bottom Waters (AABW), these deep, cold waters play a critical role in regulating circulation, temperature, and availability of oxygen and nutrients throughout the world's oceans.
Credit: Eric Taylor, Woods Hole Oceanographic Institution
- SD
The puzzle itself isn't new: past studies suggest that AABW has been undergoing significant changes for decades. Since the 1990s, an international program of repeat surveys has periodically sampled certain ocean basins around the world to track the circulation and conditions at these spots over time. Along one string of sites, or "stations," that stretches from Antarctica to the southern Indian Ocean, researchers have tracked the conditions of AABW -- a layer of profoundly cold water less than 0°C (it stays liquid because of its salt content, or salinity) that moves through the abyssal ocean, mixing with warmer waters as it circulates around the globe in the Southern Ocean and northward into all three of the major ocean basins.
- SD
It's likely this research which inspired "The Day After Tomorrow" and the current research further extends the contention there are serious changes taking place. The change they observe is dramatic.
The team found that the previously detected warming trend has continued, though at a somewhat slower pace. The biggest surprise, however, was its lack of saltiness: AABW in this region has grown fresher four times faster in the past decade than it did between 1994 and 2007.
"I thought, 'Oh wow!' when I saw the change in salinity," said Menezes. "You collect the data and sometimes you spend 2 to 3 years to find something, but this time we knew what we had within hours, and we knew it was very unexpected."
- SD
The first question coming to the Rockhouse is why should the change accelerate so quickly but the researchers can't yet answer it although they have a theory.
Questions remain around the cause of the shift. Menezes and Macdonald hypothesize that the freshening could be due to a recent landscape-changing event. In 2010, an iceberg about the size of Rhode Island collided with Antarctica's Mertz Glacier Tongue, carving out a more-than-1,000-square-mile piece and reshaping the icescape of the George V/Adelie Land Coast, where the AABW observed in this study is thought to form. The subsequent melting dramatically freshened the waters there, which may have in turn freshened the AABW as well. Future studies could use chemical analysis to trace the waters back to the site of the collision and calving and confirm the hypothesis.
- SD
Read the article for the fullness of it but there's nothing being omitted in terms of oh, my God, we're all going to freeze and die. However, there is certain evidence of changes politicians have been denying ever since "Silent Spring" in the Sixties.
Ed: not all of them!
Fair enough but you see the thinking which prevails now. Rejecting climate science comes from the same bloody mindedness as the rejection of the threat from nukes insofar as it makes a much better profit to wreck the world than fix it.
"The Day After Tomorrow" came after "The Day After" as is Hollywood's wont to do and in this one the new Ice Age came because of disturbance of the circulation of the global ocean currents.
The current research doesn't forecast anything so extreme but they do know the deep water circulation of the ocean is changing. (Science Daily: Antarctic bottom waters freshening at unexpected rate)
In some places along the Antarctic coast, ice formation causes seawater to grow saltier and therefore denser, so that it sinks to the sea floor. Known as the Antarctic Bottom Waters (AABW), these deep, cold waters play a critical role in regulating circulation, temperature, and availability of oxygen and nutrients throughout the world's oceans.
Credit: Eric Taylor, Woods Hole Oceanographic Institution
- SD
The puzzle itself isn't new: past studies suggest that AABW has been undergoing significant changes for decades. Since the 1990s, an international program of repeat surveys has periodically sampled certain ocean basins around the world to track the circulation and conditions at these spots over time. Along one string of sites, or "stations," that stretches from Antarctica to the southern Indian Ocean, researchers have tracked the conditions of AABW -- a layer of profoundly cold water less than 0°C (it stays liquid because of its salt content, or salinity) that moves through the abyssal ocean, mixing with warmer waters as it circulates around the globe in the Southern Ocean and northward into all three of the major ocean basins.
- SD
It's likely this research which inspired "The Day After Tomorrow" and the current research further extends the contention there are serious changes taking place. The change they observe is dramatic.
The team found that the previously detected warming trend has continued, though at a somewhat slower pace. The biggest surprise, however, was its lack of saltiness: AABW in this region has grown fresher four times faster in the past decade than it did between 1994 and 2007.
"I thought, 'Oh wow!' when I saw the change in salinity," said Menezes. "You collect the data and sometimes you spend 2 to 3 years to find something, but this time we knew what we had within hours, and we knew it was very unexpected."
- SD
The first question coming to the Rockhouse is why should the change accelerate so quickly but the researchers can't yet answer it although they have a theory.
Questions remain around the cause of the shift. Menezes and Macdonald hypothesize that the freshening could be due to a recent landscape-changing event. In 2010, an iceberg about the size of Rhode Island collided with Antarctica's Mertz Glacier Tongue, carving out a more-than-1,000-square-mile piece and reshaping the icescape of the George V/Adelie Land Coast, where the AABW observed in this study is thought to form. The subsequent melting dramatically freshened the waters there, which may have in turn freshened the AABW as well. Future studies could use chemical analysis to trace the waters back to the site of the collision and calving and confirm the hypothesis.
- SD
Read the article for the fullness of it but there's nothing being omitted in terms of oh, my God, we're all going to freeze and die. However, there is certain evidence of changes politicians have been denying ever since "Silent Spring" in the Sixties.
Ed: not all of them!
Fair enough but you see the thinking which prevails now. Rejecting climate science comes from the same bloody mindedness as the rejection of the threat from nukes insofar as it makes a much better profit to wreck the world than fix it.
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