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Occasional Thoughts on Climate Change


donsutherland1
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On 2/9/2024 at 9:25 PM, donsutherland1 said:

It’s an interesting paper and it confirms “tipping” behavior related to the AMOC. Tipping abruptly from one stable state into another one has been found elsewhere, so I don’t believe it is too surprising that researchers found that the same could hold true for the AMOC. IMO, had they found against tipping, that would have been a more surprising outcome.

The full paper is here:

https://www.science.org/doi/10.1126/sciadv.adk1189

 

Below is an interview with the lead author, which provides good background for understanding the study implications. The unrealistic modeling scenario is needed because current models are inadequate. Not the best position to be in with the system trending toward less stability.

.

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6 hours ago, LibertyBell said:

yep, grass fires and brush fires I just didn't know fires like that can get so BIG and so extensive.  There has to be a strong wind component too

 

I think dry grasses and brush are among the fastest burning fuels.  That's one of the tricks the deniers do by saying wildfires were worse in the 1800s.  Most of the Plains were still pristine grasslands, and there was no fire prevention effort. So dry grassfires could swallow vast acreage quickly in the typically windy Plains. It's literally impossible to have fires on that scale today, since it's all agricultural land. But these fires wouldn't have produced anywhere near the quantities of smoke from the recent conflagrations in western and northern North America.

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This is an important new study which highlights how quickly the WAIS could go if warm water gets underneath.


https://www.cnn.com/2024/02/08/climate/west-antarctic-ice-sheet-melt-collapse-climate-intl/index.html


 

CNN — 

Evidence from a 2,000-foot-long ice core reveals that the West Antarctic Ice Sheet shrank suddenly and dramatically around 8,000 years ago, according to new research — providing an alarming insight into how quickly Antarctic ice could melt and send sea levels soaring.

Part of the ice sheet thinned by 450 meters (1,476 feet) — a height greater than the Empire State Building — over a period of just 200 years at the end of the last Ice Age, according to the study published Wednesday in the journal Nature Geoscience.

It’s the first direct evidence that shows such a rapid loss of ice anywhere in Antarctica, according to the study’s authors.

While scientists knew the ice sheet was bigger at the end of the last Ice Age than today, much less was known about when exactly that shrinking happened, said Eric Wolff, a glaciologist at the University of Cambridge in the UK and a study author.

This study changes that, he told CNN. “We’ve been able to say exactly when it retreated, but we’ve also been able to say how fast it retreated.”

Now it’s clear the ice sheet retreated and thinned very rapidly in the past, Wolff said, the danger is that it could begin again. “If it does start to retreat, it really will do it very fast,” he added.

That could have catastrophic consequences for global sea level rise. The West Antarctic Ice Sheet holds enough water to raise sea levels by about 5 meters – more than 16 feet — which would cause devastating flooding in coastal towns and cities around the world.

The study is “an excellent piece of detective work” about a major part of the Antarctic ice sheet, said Ted Scambos, a glaciologist at the University of Colorado Boulder.

The key message is “the amount of ice stored in Antarctica can change very quickly — at a pace that would be hard to deal with for many coastal cities,” he told CNN.

It was a surprise when the data revealed just how quickly the ice had thinned at the end of the last Ice Age, Wolff said. “We actually spent a lot of time checking that we hadn’t made a mistake with the analysis.”

The West Antarctic Ice Sheet is particularly vulnerable to climate change, because the land under it is below sea level and slopes downward. When warm water gets underneath, it can melt very fast. “It can have a runaway process, and that’s evidently what happened 8,000 years ago,” Wolff said.

What makes the findings so alarming, said Isobel Rowell, an ice core scientist at the British Antarctic Survey and a study co-author, is that once that runaway happens “there’s really very little, if anything, that we can do to stop it,” she told CNN.

The crucial thing “is not to test it too far,” Wolff said, and that means tackling climate change. “We can avoid these tipping points still,” he said.

The new data will help improve the accuracy of the models scientists use to predict how the ice sheet will respond to future global heating, the report says.

David Thornalley, an ocean and climate scientist at University College London, said the study’s data was “striking.” He cautioned that as the study looked at a period 8,000 years ago, when climate conditions were different, the results aren’t a direct example of what could happen today. But, he added, they are still able to offer an “insight into the way that ice sheets can collapse.”

The study comes as scientists continue to sound the alarm about what is happening to the Earth’s most isolated continent.

For example, the Thwaites Glacier, also in West Antarctica, is melting rapidly. A 2022 study said the Thwaites — dubbed the Doomsday Glacier for the catastrophic impact its collapse would have on sea level rise — was hanging on “by its fingernails” as the planet warms.

This new study adds to these concerns, Scambos said. “(It) shows that the very same processes we are seeing just beginning now, in areas like Thwaites Glacier, have played out before in similar areas of Antarctica and indeed, the pace of ice loss was equal to our worst fears about a runaway ice loss.”

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16 hours ago, bluewave said:

This is an important new study which highlights how quickly the WAIS could go if warm water gets underneath.


https://www.cnn.com/2024/02/08/climate/west-antarctic-ice-sheet-melt-collapse-climate-intl/index.html


 

CNN — 

Evidence from a 2,000-foot-long ice core reveals that the West Antarctic Ice Sheet shrank suddenly and dramatically around 8,000 years ago, according to new research — providing an alarming insight into how quickly Antarctic ice could melt and send sea levels soaring.

Part of the ice sheet thinned by 450 meters (1,476 feet) — a height greater than the Empire State Building — over a period of just 200 years at the end of the last Ice Age, according to the study published Wednesday in the journal Nature Geoscience.

It’s the first direct evidence that shows such a rapid loss of ice anywhere in Antarctica, according to the study’s authors.

While scientists knew the ice sheet was bigger at the end of the last Ice Age than today, much less was known about when exactly that shrinking happened, said Eric Wolff, a glaciologist at the University of Cambridge in the UK and a study author.

This study changes that, he told CNN. “We’ve been able to say exactly when it retreated, but we’ve also been able to say how fast it retreated.”

Now it’s clear the ice sheet retreated and thinned very rapidly in the past, Wolff said, the danger is that it could begin again. “If it does start to retreat, it really will do it very fast,” he added.

That could have catastrophic consequences for global sea level rise. The West Antarctic Ice Sheet holds enough water to raise sea levels by about 5 meters – more than 16 feet — which would cause devastating flooding in coastal towns and cities around the world.

The study is “an excellent piece of detective work” about a major part of the Antarctic ice sheet, said Ted Scambos, a glaciologist at the University of Colorado Boulder.

The key message is “the amount of ice stored in Antarctica can change very quickly — at a pace that would be hard to deal with for many coastal cities,” he told CNN.

It was a surprise when the data revealed just how quickly the ice had thinned at the end of the last Ice Age, Wolff said. “We actually spent a lot of time checking that we hadn’t made a mistake with the analysis.”

The West Antarctic Ice Sheet is particularly vulnerable to climate change, because the land under it is below sea level and slopes downward. When warm water gets underneath, it can melt very fast. “It can have a runaway process, and that’s evidently what happened 8,000 years ago,” Wolff said.

What makes the findings so alarming, said Isobel Rowell, an ice core scientist at the British Antarctic Survey and a study co-author, is that once that runaway happens “there’s really very little, if anything, that we can do to stop it,” she told CNN.

The crucial thing “is not to test it too far,” Wolff said, and that means tackling climate change. “We can avoid these tipping points still,” he said.

The new data will help improve the accuracy of the models scientists use to predict how the ice sheet will respond to future global heating, the report says.

David Thornalley, an ocean and climate scientist at University College London, said the study’s data was “striking.” He cautioned that as the study looked at a period 8,000 years ago, when climate conditions were different, the results aren’t a direct example of what could happen today. But, he added, they are still able to offer an “insight into the way that ice sheets can collapse.”

The study comes as scientists continue to sound the alarm about what is happening to the Earth’s most isolated continent.

For example, the Thwaites Glacier, also in West Antarctica, is melting rapidly. A 2022 study said the Thwaites — dubbed the Doomsday Glacier for the catastrophic impact its collapse would have on sea level rise — was hanging on “by its fingernails” as the planet warms.

This new study adds to these concerns, Scambos said. “(It) shows that the very same processes we are seeing just beginning now, in areas like Thwaites Glacier, have played out before in similar areas of Antarctica and indeed, the pace of ice loss was equal to our worst fears about a runaway ice loss.”

What is interesting about the WAIS science is the aspect of momentum in the system.  It is theorized that the faltering structural integrity continues for some time ... even if/when returning to the previous colder state of the ambient hemisphere. 

The reasoning behind:  these so-called trigger points and threshold ... when they are crossed they're not linearly responsive in nature.  They are problematically very difficult to actually reverse once that happens.  Speaking very broad brushed conceptual, it is as though they fight against the change until the forcing becomes overwhelming ...then, "accept" the change all at once - the new paradigm than needs an equal opposing momentum to get the system in question to accept going back.  At which point it is not really about regressing back to a prior state - we have to look at the return, not as a return, but as a whole new paradigm.  

It's a peculiar arithmetic at these very large systemic/planetary scales.  

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On 3/10/2024 at 1:01 PM, Typhoon Tip said:

What is interesting about the WAIS science is the aspect of momentum in the system.  It is theorized that the faltering structural integrity continues for some time ... even if/when returning to the previous colder state of the ambient hemisphere. 

The reasoning behind:  these so-called trigger points and threshold ... when they are crossed they're not linearly responsive in nature.  They are problematically very difficult to actually reverse once that happens.  Speaking very broad brushed conceptual, it is as though they fight against the change until the forcing becomes overwhelming ...then, "accept" the change all at once - the new paradigm than needs an equal opposing momentum to get the system in question to accept going back.  At which point it is not really about regressing back to a prior state - we have to look at the return, not as a return, but as a whole new paradigm.  

It's a peculiar arithmetic at these very large systemic/planetary scales.  

We might have to start dumping all this extra water into space.... maybe ship it to Mars for the new colony?

 

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On 3/9/2024 at 7:33 PM, bluewave said:

This is an important new study which highlights how quickly the WAIS could go if warm water gets underneath.


https://www.cnn.com/2024/02/08/climate/west-antarctic-ice-sheet-melt-collapse-climate-intl/index.html


 

CNN — 

Evidence from a 2,000-foot-long ice core reveals that the West Antarctic Ice Sheet shrank suddenly and dramatically around 8,000 years ago, according to new research — providing an alarming insight into how quickly Antarctic ice could melt and send sea levels soaring.

Part of the ice sheet thinned by 450 meters (1,476 feet) — a height greater than the Empire State Building — over a period of just 200 years at the end of the last Ice Age, according to the study published Wednesday in the journal Nature Geoscience.

It’s the first direct evidence that shows such a rapid loss of ice anywhere in Antarctica, according to the study’s authors.

While scientists knew the ice sheet was bigger at the end of the last Ice Age than today, much less was known about when exactly that shrinking happened, said Eric Wolff, a glaciologist at the University of Cambridge in the UK and a study author.

This study changes that, he told CNN. “We’ve been able to say exactly when it retreated, but we’ve also been able to say how fast it retreated.”

Now it’s clear the ice sheet retreated and thinned very rapidly in the past, Wolff said, the danger is that it could begin again. “If it does start to retreat, it really will do it very fast,” he added.

That could have catastrophic consequences for global sea level rise. The West Antarctic Ice Sheet holds enough water to raise sea levels by about 5 meters – more than 16 feet — which would cause devastating flooding in coastal towns and cities around the world.

The study is “an excellent piece of detective work” about a major part of the Antarctic ice sheet, said Ted Scambos, a glaciologist at the University of Colorado Boulder.

The key message is “the amount of ice stored in Antarctica can change very quickly — at a pace that would be hard to deal with for many coastal cities,” he told CNN.

It was a surprise when the data revealed just how quickly the ice had thinned at the end of the last Ice Age, Wolff said. “We actually spent a lot of time checking that we hadn’t made a mistake with the analysis.”

The West Antarctic Ice Sheet is particularly vulnerable to climate change, because the land under it is below sea level and slopes downward. When warm water gets underneath, it can melt very fast. “It can have a runaway process, and that’s evidently what happened 8,000 years ago,” Wolff said.

What makes the findings so alarming, said Isobel Rowell, an ice core scientist at the British Antarctic Survey and a study co-author, is that once that runaway happens “there’s really very little, if anything, that we can do to stop it,” she told CNN.

The crucial thing “is not to test it too far,” Wolff said, and that means tackling climate change. “We can avoid these tipping points still,” he said.

The new data will help improve the accuracy of the models scientists use to predict how the ice sheet will respond to future global heating, the report says.

David Thornalley, an ocean and climate scientist at University College London, said the study’s data was “striking.” He cautioned that as the study looked at a period 8,000 years ago, when climate conditions were different, the results aren’t a direct example of what could happen today. But, he added, they are still able to offer an “insight into the way that ice sheets can collapse.”

The study comes as scientists continue to sound the alarm about what is happening to the Earth’s most isolated continent.

For example, the Thwaites Glacier, also in West Antarctica, is melting rapidly. A 2022 study said the Thwaites — dubbed the Doomsday Glacier for the catastrophic impact its collapse would have on sea level rise — was hanging on “by its fingernails” as the planet warms.

This new study adds to these concerns, Scambos said. “(It) shows that the very same processes we are seeing just beginning now, in areas like Thwaites Glacier, have played out before in similar areas of Antarctica and indeed, the pace of ice loss was equal to our worst fears about a runaway ice loss.”

I think at some point, we'll have to start pumping all this excess water off the planet....

 

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4 hours ago, LibertyBell said:

wow it's not even summer yet, what are the implications for the summer for these places?

 

Don't have much info on Africa, but this could be the warm season for at least some of area. A portion of Africa is in the SHemi and the rest is tropical, with sun overhead at the spring equinox.

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I have been working with the great folks at the Delaware Environmental Observing System (Thanks to Chris!!) to add even more weather observation points and stations across Chester County PA. With the updated data and summer coming I thought I would run an analysis of Summer (June-August) temperatures across the County from 1895 through last summer (now with 25 Chester County Stations at least partially in the data since 1895 and 15 current observation sites included). Overall in the non-adjusted data there is only as expected normal cyclical warm and cool cycles but I thought I would show you a comparison of the post observation adjustment applied by the the National Center of Environmental Information (NCEI) who have applied an incredible 111 consecutive years of post observation adjustments to chill the actual observations to each and every summer from 1895 through 2005 and have now every year since 2005 now applied a warming adjustment. As you can see in the trend lines the orange non-adjusted and blue adjusted paint a far different rate of our rate of warming. My friend Charlie will of course tell us these 111 straight years of cooling adjustments and now 20 years of warming are science based.....

image.thumb.png.a1fce6d223d9b60662d1cf1a1e4bb8f6.png

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14 hours ago, ChescoWx said:

I have been working with the great folks at the Delaware Environmental Observing System (Thanks to Chris!!) to add even more weather observation points and stations across Chester County PA. With the updated data and summer coming I thought I would run an analysis of Summer (June-August) temperatures across the County from 1895 through last summer (now with 25 Chester County Stations at least partially in the data since 1895 and 15 current observation sites included). Overall in the non-adjusted data there is only as expected normal cyclical warm and cool cycles but I thought I would show you a comparison of the post observation adjustment applied by the the National Center of Environmental Information (NCEI) who have applied an incredible 111 consecutive years of post observation adjustments to chill the actual observations to each and every summer from 1895 through 2005 and have now every year since 2005 now applied a warming adjustment. As you can see in the trend lines the orange non-adjusted and blue adjusted paint a far different rate of our rate of warming. My friend Charlie will of course tell us these 111 straight years of cooling adjustments and now 20 years of warming are science based.....

image.thumb.png.a1fce6d223d9b60662d1cf1a1e4bb8f6.png

I don’t understand this obsession with using flawed data. Why would you use the unadjusted numbers when they have known biases? How does that make more sense than adjusting for the biases?

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It's important to note when people complain about adjustments to the temperature record, what they are really saying is that they want to use flawed data because it gives them a more favored result. Time of observation makes a HUGE difference, especially in the summertime when weather variance tends to be at an annual minimum. We know this, and we correct for it.

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4 hours ago, TheClimateChanger said:

It's important to note when people complain about adjustments to the temperature record, what they are really saying is that they want to use flawed data because it gives them a more favored result. Time of observation makes a HUGE difference, especially in the summertime when weather variance tends to be at an annual minimum. We know this, and we correct for it.

Time bias does not make a material difference as long as consistent obs are taken over 365 days - while making post observation chilling adjustments for 111 straight years and then warming the last 20 does not give anyone comfort in the data and trends is purports to show. I actually went back and recast my observations from 8pm to the current 24 hours for 3 years of data. The difference was less than 0.002 degrees.

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12 hours ago, ChescoWx said:

Time bias does not make a material difference as long as consistent obs are taken over 365 days - while making post observation chilling adjustments for 111 straight years and then warming the last 20 does not give anyone comfort in the data and trends is purports to show. I actually went back and recast my observations from 8pm to the current 24 hours for 3 years of data. The difference was less than 0.002 degrees.

As usual you are jumping to the wrong conclusion based on lousy analysis. You aren't controlling for differences in average temperature  between stations. Every time you change the stations included in your County average, you get a different result. To get a cooler result add in some relatively cool stations. I don't see any recent "warming adjustment" for NOAA when I compare to your own Chescowx series. Quite the contrary NOAA and Chescowx are in good agreement on the warming rate over the past 54 years. Good news for your post-1970 data.

NOAAChescowx.PNG.ff9d0ef802cc24b2e8006944ce0183b4.PNG

As for the older pre-1970 data, yes we know you get a different answer for the raw vs bias adjusted. You are beating a dead horse by making the same comparison over and over again. We have a handful of older stations in Chester County. Adjustments for each station are published and not close to the "adjustments" you are coming up with in your latest. All the adjustments are based on comparison to other stations. If time of observation bias (TOB)  didn't impact a particular station it won't contribute to that stations' bias adjustment. There are many reasons for bias adjustment besides TOB: shelter, aspiration, digital vs analog, moving equipment, broken instrument, a tree growing nearby, a tree cut down, etc. 

Deniers have been complaining about "science-based" station adjustments for decades. But they never complete the technical analysis needed to provide evidence in a scientific forum. Without submitting material to a scientific forum your complaints about adjustments are a waste of time. You can whine all you want on a weather board but it isn't going to move the scientific needle.

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Hi all - I'm usually in the NYC Metro boards watching for snow.  I was hoping to please get some insights on something I read today.

I read a tweet from someone named Chris Martz who stated the following: "In 2009, experts told CBS News that the Arctic will be ice-free within 10-years' time. As of yesterday, there is more sea ice in the Arctic than there was when this prediction was made, and it has been tracking higher than 2005 just about every day this year."

It seems like I'm always hearing totally divergent things about the level of Arctic sea ice  - that it's at record lows, that it's above normal, etc.  The tweet above is just the latest example.

Why is there always (or seems to be always) such a wide range of news regarding Arctic sea ice, and how does it actually look currently compared to say 10, 25, 50 years ago?

Thanks in advance..

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12 hours ago, chubbs said:

As usual you are jumping to the wrong conclusion based on lousy analysis. You aren't controlling for differences in average temperature  between stations. Every time you change the stations included in your County average, you get a different result. To get a cooler result add in some relatively cool stations. I don't see any recent "warming adjustment" for NOAA when I compare to your own Chescowx series. Quite the contrary NOAA and Chescowx are in good agreement on the warming rate over the past 54 years. Good news for your post-1970 data.

NOAAChescowx.PNG.ff9d0ef802cc24b2e8006944ce0183b4.PNG

 

 

So let's correct your above with the actual raw data analysis below. What you call ChescoWx above let's break it into just the actual 3 stations (not the up to 24 stations we have in the actual data) Coatesville 1E / Coatesville 2W and East Nantmeal averaged together vs. the NCEI adjustments. You can clearly see the warming adjustment - now up to 0.77  degrees in the most recent complete decade!  So they cooled the first 8 decades and warmed the last 4 - voila that gives you the blue warming line vs. the actual data not warming at all and in fact showing cooling.

 

image.png.6ae217c376e76b7ded85642f9191e615.png

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And again below is all stations with up to 17 actual reporting sites included in the most recent 2 decades. The same pattern of large chilling adjustments for 111 years and now increasing warming adjustments as you can clearly see during the past 2 decades. Why the post observation warming adjustments of 0.3 degrees in the 2010's? Is it time of obs? bad equipment? Do we know the exact answer??

 

image.png.9dd8ad498f2ecb700bff7a6bed9e4191.png

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21 hours ago, ChescoWx said:

And again below is all stations with up to 17 actual reporting sites included in the most recent 2 decades. The same pattern of large chilling adjustments for 111 years and now increasing warming adjustments as you can clearly see during the past 2 decades. Why the post observation warming adjustments of 0.3 degrees in the 2010's? Is it time of obs? bad equipment? Do we know the exact answer??

 

image.png.9dd8ad498f2ecb700bff7a6bed9e4191.png

Your county averaging method doesn't agree with your own Chescowx series and the year-to-year differences are probably even larger; smoothed somewhat by the decade averaging. Not surprising because you aren't controlling for differences in average temperature between stations. Every time you add or subtract a station you change the average.

chesavg.PNG.c2168cca308a8a88d1ae6f8cfff20d49.PNG

 

NOAA on-the-other-hand agrees very well with the ERA5 re-analysis developed by EMWCF, both on year-to-year temperature changes and on the overall warming since 1950. NOAA and ERA5 are completely independent using different datasets and methods, so agreement at the County level increases confidence in both series. Bottom-line - scientists have a good handle on Chester County temperature trends. If you aren't matching NOAA or ERA5 you aren't getting an accurate depiction of our local climate.  Below is a link which provides background on ERA5, which has land temperature data back to 1950. Note that I can only get ERA data for a lat/long square that approximates Chesco.

https://climate.copernicus.eu/climate-reanalysis

eranoaa.PNG.6cdd000cd018aebbf172e06966e6b40e.PNG

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