|
Post by Ratty on Jul 25, 2020 13:20:25 GMT
|
|
|
Post by missouriboy on Jul 27, 2020 16:11:42 GMT
CO2 Explains Everything Historic carbon dioxide decline could hold clues for future climate
by Australian National University phys.org/news/2020-07-historic-carbon-dioxide-decline-clues.htmlCredit: Pixabay A new study led by researchers at The Australian National University (ANU) provides a clearer snapshot of conditions during the last ice age—when global ice sheets were at their peak—and could even lead to better models for future climate projections. The study demonstrates a new way of recreating ocean conditions in the Atlantic during the Last Glacial Maximum (LGM)—around 20,000 years ago. Lead author Dr. Jimin Yu says scientists have been trying to reconstruct ocean circulation for this time period for decades, because of the clues it offers about past CO2 levels and changes in climate. "The LGM was a time of much lower CO2 levels, lower global temperature and lower sea levels," Dr. Yu said. The researchers say old ocean models cannot explain recently published data on the LGM, meaning a change in thinking was needed. Using marine sediments to reconstruct deep-water carbonate ion—which traces reflecting seawater acidity—the group generated a first-of-its kind map showing water conditions for the last glacial Atlantic. This map reveals a new glacial deep Atlantic circulation model. "We found that carbon-rich Pacific Deep Water extended northward up to about 20° S in the South Atlantic at three to four kilometers depth during the Last Glacial Maximum," Dr. Yu said. "This may have contributed critically to the decline in atmospheric CO2, thereby helping to initiate the glacial maximum." According to Dr. Yu, ocean circulation is a key regulator of climate, storing and transporting heat, carbon and nutrients. "This study suggests as waters shifted during the LGM, carbon was stored in the deep ocean, lowering atmospheric CO2 levels," Dr. Yu said. This information could also help improve or test the performance of various climate models. "If a model is able to reproduce the data—a method known as hindcasting or backtesting—it might give us confidence in the model's ability to map out future climate conditions," Dr. Yu said.
|
|
|
Post by nautonnier on Jul 27, 2020 16:38:27 GMT
CO2 Explains Everything Historic carbon dioxide decline could hold clues for future climate
by Australian National University phys.org/news/2020-07-historic-carbon-dioxide-decline-clues.htmlCredit: Pixabay A new study led by researchers at The Australian National University (ANU) provides a clearer snapshot of conditions during the last ice age—when global ice sheets were at their peak—and could even lead to better models for future climate projections. The study demonstrates a new way of recreating ocean conditions in the Atlantic during the Last Glacial Maximum (LGM)—around 20,000 years ago. Lead author Dr. Jimin Yu says scientists have been trying to reconstruct ocean circulation for this time period for decades, because of the clues it offers about past CO2 levels and changes in climate. "The LGM was a time of much lower CO2 levels, lower global temperature and lower sea levels," Dr. Yu said. The researchers say old ocean models cannot explain recently published data on the LGM, meaning a change in thinking was needed. Using marine sediments to reconstruct deep-water carbonate ion—which traces reflecting seawater acidity—the group generated a first-of-its kind map showing water conditions for the last glacial Atlantic. This map reveals a new glacial deep Atlantic circulation model. "We found that carbon-rich Pacific Deep Water extended northward up to about 20° S in the South Atlantic at three to four kilometers depth during the Last Glacial Maximum," Dr. Yu said. "This may have contributed critically to the decline in atmospheric CO2, thereby helping to initiate the glacial maximum." According to Dr. Yu, ocean circulation is a key regulator of climate, storing and transporting heat, carbon and nutrients. "This study suggests as waters shifted during the LGM, carbon was stored in the deep ocean, lowering atmospheric CO2 levels," Dr. Yu said. This information could also help improve or test the performance of various climate models. "If a model is able to reproduce the data—a method known as hindcasting or backtesting—it might give us confidence in the model's ability to map out future climate conditions," Dr. Yu said. And as every climate 'scientist' will tell you correlation IS causation. ![;-|](//storage.proboards.com/forum/images/smiley/squint.png) Downwelling Infrared (if such a thing exists) cannot warm water indeed it may even cool water due to enhancing surface evaporation. Therefore, reducing infrared could even lead to a warmer SST due to reduced evaporative cooling Does anyone do actual hands on modeling of real systems these days rather than parameterized apps that are coded to show the results that the researchers want?
|
|
|
Post by missouriboy on Jul 27, 2020 16:39:02 GMT
Best find of the year ... in the eyes of a data junkie. ![:)](//storage.proboards.com/forum/images/smiley/smiley.png) Now where can I get that data series? Man, I love it when two totally separate datasets line up in such an excellent fashion. I’d say that the Colle Gnifetti ice core tracks the northern hemisphere temperature very well. The only real anomaly is recent when the two diverge. No idea what that’s about. (sense of dry humor indicator) The hockey stick lost its shaft! Must be hiding in some dark region. ![](https://i2.wp.com/wattsupwiththat.com/wp-content/uploads/2020/07/gnifetti-and-berkeley-1750-to-2006.png?w=689&ssl=1)
|
|
|
Post by missouriboy on Jul 27, 2020 22:44:50 GMT
Compare the GISP2 chart to the Central Alps chart. Although the resolution is finer and the temperature deviation range is somewhat different, the major trends hold together very well. Don't know how fine the sampling range was on the GISP2, but it covers 10,000+ years versus ~1200 years in the Alps. One would also expect the climate ranges to be a bit different from Greenland to Central Europe. The fact that the major peaks, troughs and trends across the data sets are similar says a lot. ![](https://i1.wp.com/wattsupwiththat.com/wp-content/uploads/2020/07/gnifietti-biennial-temps-plus-gaussian.png?w=689&ssl=1) ![](http://dl.dropbox.com/s/7tz3o5px4qf1qrz/GISP2-alley-2004.jpg?dl=0)
|
|
|
Post by Ratty on Jul 28, 2020 3:22:02 GMT
CO2 Explains Everything Historic carbon dioxide decline could hold clues for future climate
by Australian National University phys.org/news/2020-07-historic-carbon-dioxide-decline-clues.htmlCredit: Pixabay A new study led by researchers at The Australian National University (ANU) provides a clearer snapshot of conditions during the last ice age—when global ice sheets were at their peak—and could even lead to better models for future climate projections. The study demonstrates a new way of recreating ocean conditions in the Atlantic during the Last Glacial Maximum (LGM)—around 20,000 years ago. Lead author Dr. Jimin Yu says scientists have been trying to reconstruct ocean circulation for this time period for decades, because of the clues it offers about past CO2 levels and changes in climate. "The LGM was a time of much lower CO2 levels, lower global temperature and lower sea levels," Dr. Yu said. The researchers say old ocean models cannot explain recently published data on the LGM, meaning a change in thinking was needed. Using marine sediments to reconstruct deep-water carbonate ion—which traces reflecting seawater acidity—the group generated a first-of-its kind map showing water conditions for the last glacial Atlantic. This map reveals a new glacial deep Atlantic circulation model. "We found that carbon-rich Pacific Deep Water extended northward up to about 20° S in the South Atlantic at three to four kilometers depth during the Last Glacial Maximum," Dr. Yu said. "This may have contributed critically to the decline in atmospheric CO2, thereby helping to initiate the glacial maximum." According to Dr. Yu, ocean circulation is a key regulator of climate, storing and transporting heat, carbon and nutrients. "This study suggests as waters shifted during the LGM, carbon was stored in the deep ocean, lowering atmospheric CO2 levels," Dr. Yu said. This information could also help improve or test the performance of various climate models. "If a model is able to reproduce the data—a method known as hindcasting or backtesting—it might give us confidence in the model's ability to map out future climate conditions," Dr. Yu said. Beware the ANU, a woke organisation in a woke city. ![B-|](//storage.proboards.com/forum/images/smiley/notamused.png)
|
|
|
Post by missouriboy on Jul 28, 2020 5:49:31 GMT
Beware the ANU, a woke organisation in a woke city. ![B-|](//storage.proboards.com/forum/images/smiley/notamused.png) They need a nap.
|
|
|
Post by missouriboy on Jul 28, 2020 21:49:46 GMT
ACID. Maybe I've asked this before. But, in your roamings through the nether climate data regions, have you yet come across a historical data set of jetstream lineations ... or something that would serve as a proxy? What I'm looking for is something that could quantify loopiness over time and space. NAO of course gives a feel for one longitudinal swath ... a surface proxy.
|
|
|
Post by acidohm on Jul 29, 2020 9:13:22 GMT
ACID. Maybe I've asked this before. But, in your roamings through the nether climate data regions, have you yet come across a historical data set of jetstream lineations ... or something that would serve as a proxy? What I'm looking for is something that could quantify loopiness over time and space. NAO of course gives a feel for one longitudinal swath ... a surface proxy. Not off the top of my head, but i can ask someone who knows more then i do.
|
|
|
Post by nautonnier on Jul 29, 2020 9:35:19 GMT
ACID. Maybe I've asked this before. But, in your roamings through the nether climate data regions, have you yet come across a historical data set of jetstream lineations ... or something that would serve as a proxy? What I'm looking for is something that could quantify loopiness over time and space. NAO of course gives a feel for one longitudinal swath ... a surface proxy. As they were only really discovered around the time of the 2nd World War, anything earlier than 1950's would need to be proxies. Sounds like a good PhD project.
|
|
|
Post by Ratty on Jul 29, 2020 12:43:25 GMT
ACID. Maybe I've asked this before. But, in your roamings through the nether climate data regions, have you yet come across a historical data set of jetstream lineations ... or something that would serve as a proxy? What I'm looking for is something that could quantify loopiness over time and space. NAO of course gives a feel for one longitudinal swath ... a surface proxy. What indicators would serve as a proxy for the jetstream? Tree rings on a Siberian peninsula? ![;)](//storage.proboards.com/forum/images/smiley/wink.png)
|
|
|
Post by nautonnier on Jul 29, 2020 13:46:50 GMT
ACID. Maybe I've asked this before. But, in your roamings through the nether climate data regions, have you yet come across a historical data set of jetstream lineations ... or something that would serve as a proxy? What I'm looking for is something that could quantify loopiness over time and space. NAO of course gives a feel for one longitudinal swath ... a surface proxy. What indicators would serve as a proxy for the jetstream? Tree rings on a Siberian peninsula? ![;)](//storage.proboards.com/forum/images/smiley/wink.png) Or perhaps A Tree 's rings on a Siberian peninsula
|
|
|
Post by nautonnier on Jul 29, 2020 14:20:50 GMT
|
|
|
Post by missouriboy on Jul 29, 2020 21:39:29 GMT
ACID. Maybe I've asked this before. But, in your roamings through the nether climate data regions, have you yet come across a historical data set of jetstream lineations ... or something that would serve as a proxy? What I'm looking for is something that could quantify loopiness over time and space. NAO of course gives a feel for one longitudinal swath ... a surface proxy. Not off the top of my head, but i can ask someone who knows more then i do. I did a test play with meteociel which allows one to grab an annimated gif. Their coverage options include pressures and anomalies at 500 hPa. Unfortunately, there online archives, which they show going back to 2007, are really only available from several years later. The 2 gifs below are pressure anomalies for 6 to 192 hours on January 15 and January 29, 2018. ![](https://images.meteociel.fr/im/2902/anim_nbb5.gif) ![](https://images.meteociel.fr/im/8966/anim_koz4.gif)
|
|
|
Post by acidohm on Jul 30, 2020 5:02:58 GMT
Not off the top of my head, but i can ask someone who knows more then i do. I did a test play with meteociel which allows one to grab an annimated gif. Their coverage options include pressures and anomalies at 500 hPa. Unfortunately, there online archives, which they show going back to 2007, are really only available from several years later. The 2 gifs below are pressure anomalies for 6 to 192 hours on January 15 and January 29, 2018. ![](https://images.meteociel.fr/im/2902/anim_nbb5.gif) ![](https://images.meteociel.fr/im/8966/anim_koz4.gif) An analysis of pressure systems via wetterzentral which goes back to mid 1800 is likely the best decent picture on jet behaviour??
|
|