This year’s first open thread on climate science topics. Usual rules apply – and let’s make a particular effort to stay substantive and not devolve into empty bickering (you still have Facebook for that).
Any expectations or predictions for climate science in 2019?
John Kelly says
Regarding ice and energy, I get that SLR from ice (not thermal expansion) is not just straight up melting, but more importantly ice sheet collapse from ice shelf melting resulting in increased flow into the sea. I was just curious about how the extra energy in the system compares to the amount of ice ultimately available for melting. I ended up looking it up myself, but from a variety of sources unfortunately from different dates. It is such a BOE thing I didn’t bother nailing everything down. Also my significant digits are off.
I got total ice on earth of 33mm km3, or 30,261 x 10’15 kg. At 334 kj to melt 1kg, I figured 10.107 x 10’24 j to melt all the ice on the planet. In a skeptical science post, I saw a 2012 estimate of 8 x 10’21 j of extra energy added to earth from AGW each year. At that rate, if all the energy was put to work melting ice, I figured it would take 1,263 years to melt all the planet’s ice.
Again, if 100% of the energy went to ice melt, each year 26,200 km3 of ice would melt. If 395 km3 ice melt yields 1mm of SLR, that would be 66mm of SLR per year. As a reasonableness check, if only 3% of the current energy goes to melting ice, that would be 2mm per year SLR. Given that current SLR is 3.4mm per year, including thermal expansion, I think I at least have my orders of magnitude right.
Taking it a step sideways and further, I figured it would take about 121 x 10’21 j to melt enough ice to raise SL 1 meter. Given that the current increase in OHC since 1940 is estimated at 427.3 x 10’21j, if you dropped (or slid) into the ocean enough ice from the sheets to raise SL 3.53 meters, the melting of those ice cubes would use up all of the extra OHC people are responsible for. Cooling the ocean might not be great for the coastlines, but it would work wonders for the coral reefs. Is this a thing, that melting massive ice discharge into the ocean would cool the ocean materially? It would seem reasonable to expect disruption of ocean currents, weather patterns, etc.
I realize most of this doesn’t have anything to do with the way the earth system absorbs and distributes heat, was just curious.
Hank Roberts says
Science — there’s always more to look into.
Research Letter
Spatiotemporal Variability in the Climate Growth Response of High Elevation Bristlecone Pine in the White Mountains of California
Andrew G. Bunn
Matthew W. Salzer
Kevin J. Anchukaitis
Jamis M. Bruening
Malcolm K. Hughes
First published: 29 November 2018
https://doi.org/10.1029/2018GL080981
MA Rodger says
Golly!!
A second worthwhile story for the “skyrocketeers” to start bleating about, this one from the Met Office (comment of which I hopefully post on the right thread ths time, unlike the last). Mind I hope they note that the Met Office prediction is for monthly MLO CO2 readings peaking in May at 414.7ppm, and perhaps also that they were a tad high with their predictions last year (by about 0.9ppm).
CO2 Carrie says
https://www.theguardian.com/environment/2019/jan/25/worrying-rise-in-global-co2-forecast-for-2019
Worrying’ rise in global CO2 forecast for 2019
Levels of the climate-warming gas are set to rise by near-record amounts, Met Office predicts
The Met Office has a good record of forecasting global CO2 levels and predicts that the average rise over 2019 will be 2.75 parts per million (ppm). That would put it among the highest annual rises in the 62 years since good records began.
Only years with strong El Niño events, 1998 and 2016, are likely to be higher. The rise in 2016 was 3.39ppm. In the decade after the first measurement on the Hawaiian volcano Mauna Loa in 1956, annual rises were less than 0.9ppm per year.
An El Niño event occurs when the tropical Pacific swings into a warm phase, causing many regions to have warmer and drier weather. Trees and plants are natural carbon sinks because they absorb CO2 as they grow, but this is reduced in El Niño years.
“This year we expect these carbon sinks to be relatively weak, so the impact of record high human-caused emissions will be larger than last year,” said Betts.
The Met Office forecasts an average CO2 level in 2019 of 411ppm. Monthly averages are expected to peak at 415ppm in May, before the growing season temporarily reduces levels to 408ppm in September, when CO2 will begin rising once again.
The level of CO2 in the atmosphere before the industrial revolution sparked the large-scale burning of coal, oil and gas was 280ppm.
carrie the tin can, can! says
194 MA Rodger says: “….. as you seem to be implying”
It’s all in your head. Dream on. Find another obsessive hobby, I’m taken thank you very much
Carrie says
193
mike says: “…. to see if we are seeing a plume of CO2 from approximately due east from MLO, originating from LA and the SW generally, that has been flowly directly to MLO and creating these spikey numbers.”
Isn’t that unlikely? I thought the air masses tended to flow west to east round the globe? Isn’t it too far from LA for an air pattern to move continental air that far west?
If something like that as behind these spikey numbers I’d be looking toward Chinas direction or maybe the forests of Borneo or Thailand or something (?) like that.
also imo emissions numbers are too unreliable with with too many ‘assumptions/estimates’ making them up. both recently and in years gone by to be able to fairly make any comparison to PPM.
Carrie says
PS besides the issue is CO2 levels. That’s what drives the temps up, no matter where that CO2 comes from human or natural sources.
It’s well known one of the consequences of higher human emissions leads to higher temps which must then lead to forcing of CO2 out of the natural reservoirs of vegetation and soils by various mechanisms through changes in max temps and drier conditions in hot spots.
For all we know atm maybe something like this happening somewhere without an el nino being the main/obvious driver this time. weather and climate has already changed substantially.
https://www.nasa.gov/press-release/nasa-pinpoints-cause-of-earth-s-recent-record-carbon-dioxide-spike
Ray Ladbury says
Barton@191
This is probably better suited to the Forced Variations section as it is way off topic for climate science. Look for a reply there, or I could email you–as this is a subject I have given a lot of thought to.
MA Rodger says
Our first global surface temperature record posted for December is Berkeley Earth as both NOAA & GISTEMP use ERSST which has been caught up in the tantrum of the child on Pennsylvania Ave. BEST uses HadSST so is unaffected.
BEST posts a December anomaly at +0.87ºC, a bit of a rise from November’s +0.74ºC and the third highest anomaly of 2018 (behind April October). The range of the monthly anomalies for the year was from +0.91ºC down to +0.69ºC.
It is 4th warmest December in BEST behind previous warm Decembers 2015 (+1.09ºC), 2017 (+0.90ºC) & 2016 (+0.89ºC).
December 2018 is the 25th warmest monthly anomaly on the full all-month BEST record.
As long expected, 2018 has come in as the 4th warmest year on the BEST record. The top ten warmest years on the BEST record are thus:-
1st .. 2016 … … 0.97ºC
2nd .. 2017 … … 0.85ºC
3rd .. 2015 … … 0.83ºC
4th .. 2018 … … 0.79ºC
5th .. 2010 … … 0.71ºC
6th .. 2014 … … 0.69ºC
7th .. 2005 … … 0.68ºC
8th .. 2007 … … 0.64ºC
9th .. 2009 … … 0.64ºC
10th .. 2013 … … 0.63ºC
Of the last 10 years, only two years are not in this top-ten, but they are not much cooler than tenth spot – 2012 (14th +0.60ºC) & 2011 (16th +0.59ºC).
Mal Adapted says
Kevin McKinney:
Good comment, Kevin. I’m also an atheist, in the classical or dictionary sense (can’t say I care much for the definitions of ‘strong’ and ‘weak’ atheism, however). I nonetheless recognize the need to assign subjective priority of preference to some states of the universe over others: a requirement that science can’t help with, other than to inform us of the range of likely states. It seems to me that belief as you’re describing it is only the conscious outcome of a lengthy and complex chain of unconscious cognitive processes, each with proximate and ultimate causes. For example, I have little doubt my personal ethical stance owes much to my instantiation of the Homo sapiens genome; to six years of Sunday school in my parents’ liberal protestant church, before digging in my heels at age 12; and to the rest of my upbringing as the son of a science professor in a university town. Then there’s everything that’s happened since!
I would say that ‘free will’ exists, but only within very limited behavioral ranges, under a narrow range of conditions. My participation on RC, for example 8^).
Hank Roberts says
https://www.abc.net.au/news/2019-01-25/heard-island-australias-mysterious-land-of-fire-and-ice/10713860
mike says
to Hank at 196: are you making things sound worse than they really are? You say “Antarctica gets ready to uncork a rush of glaciers to the sea, as sea ice disappears.” but the article says the rate of loss is close to 2005 and and 2010. Yes, it’s the fastest rate of loss in the satellite record, but do you really think Antarctica is getting ready to uncork a rush of glaciers to the sea? Is it that different from 2005 and 2010? I don’t track Antarctic sea ice and glacier loss. Maybe you are correct, but since you have urged folks here to not make too much of certain stories or measurements, I feel like it makes sense to ask you to be careful as well. Sound right?
to Carrie at 189: Better day on CO2, yoy increase dropped back down after a few pretty spikey days.
Daily CO2
January 23, 2019: 410.47 ppm
January 23, 2018: 408.85 ppm
co2.earth
I read somewhere that we are likely to move into EN conditions in 2019. If that turns out to be true, then we will see some big yoy comparisons. Emissions for 2018 were in rise mode, so it makes sense that we would be seeing a little jump, but the story remains unchanged: we need to see the CO2 rise number start dropping toward zero and I don’t see it yet. It would take several years (preferably 5-10) to be persuasive to me, but emission numbers for 2018 have probably made it more difficult to spot a positive trend like that for now. The emission and accumulation numbers are currently going in the wrong direction and I don’t think it’s possible to identify any change in the trend at this time. The CO2 numbers don’t need to “skyrocket” (whatever that means?) to be troubling. They are troubling numbers if they simply keep going up. 410 ppm is not where we want to be.
Cheers, chin up, everyone
Mike
Hank Roberts says
https://psmag.com/environment/are-we-headed-toward-the-worst-case-climate-change-scenario
Hank Roberts says
Oh, yeah, there’s more. Oops.
https://psmag.com/environment/are-we-headed-toward-the-worst-case-climate-change-scenario
Hank Roberts says
More phenology
from: WILDLIFE MATTERS
Center for Wildlife Monthly E-newsletter
Karsten V. Johansen says
Could some of the experts here comment on these numbers from BP which seem to be rather dubious:
https://www.bp.com/en/global/corporate/energy-economics/statistical-review-of-world-energy/co2-emissions.html
Omega Centauri says
Not an expert on air transport through still porous ice, but I would think that air has a hard time diffusing through meters of ice, so the trapped air is probably closer to the age of the surrounding ice than your estimates.
Killian says
The article includes the observation that food systems enhancement via human-managed polycultures persisted through climate changes.
A key aspect of what I would term regenerative systems is the extensive management of water.
I wonder to what degree the human-mediated infiltratiin of water affected droughts, forest extent changes, die-offs, etc?
https://www.nature.com/articles/s41477-018h-0205-y
John Kelly says
To answer my own question about ice melt materially cooling the ocean, of course the answer is yes. Hansen’s Ice Melt paper, figure 6, shows 2096 surface air temperature 0.33 C *below* an 1880-1920 baseline, assuming an aggressive ice melt doubling time of 10 years, which would equate to a 5m SLR by that time. If I’m reading the map right, the UK would be 10 C colder than the baseline, a different catastrophe than we’re used to considering.
mike says
wrt to sea ice loss, etc.: all we have to do is take immediate and drastic action to avoid the worst-case climate scenario.
per Kate Wheeling article headline: “A series of recent studies and reports suggest that, without immediate and drastic action, the worst-case climate scenario will become the rule rather than the exception.”
The emphasis on the worst-case scenariou can be disheartening to human beings. We need to stay optimistic and cheerful so that we do not lose momentum to build on the changes that we have already made. Apparently, we only have to step up our actions to a certain extent and we are in the clear.
I am not clear what exactly would qualify as immediate and drastic action. I think that needs to be spelled out so that we all know what needs to be done.
Chin up, everyone. Stay positive!
Thinks are looking good on recent noisy CO2 calculations:
Daily CO2
January 23, 2019: 410.47 ppm
January 23, 2018: 408.85 ppm
Keep up the good work! Immediate and drastic action! How hard can that be for a species like our own?
Cheers,
Mike
Mr. Know It All says
216 – Karsten
“Could some of the experts here comment on these numbers from BP which seem to be rather dubious:”
Karsten,
Those are the real numbers. They are not from BP. They are from the International Energy Agency. Not sure how they get the data, perhaps from energy companies like BP? Western nation data should be fairly accurate, but there would be no way to know the emissions from China due to the state control of the data – it could actually be 2 or 3 times the numbers we hear about – would not surprise me a bit; about as reliable as the emissions data from VWs. :)
https://www.iea.org/geco/
If you want to see the whole 15 page report click “Download the Full Report”.
Clearly the US emissions are falling while most of the rest of the world, including the EU with their carbon taxes, are rising. Emissions in China and perhaps India are exploding – mostly fueled by money from exports, much of that to the US. Clearly US has lifted the entire developing world from poverty in just the last few decades by outsourcing our manufacturing, and leaving many ‘Muricans with low-paying jobs, while China houses millions in concentration camps. That’s the harsh reality – quite the opposite to the rosy China picture painted by many in posts above.
Oil is on the way out, although slowly for now. Fracked wells are declining in output already, and the price of oil is low enough that there is a drop in drilling activity:
https://www.zerohedge.com/news/2019-01-26/shale-pioneer-hamm-output-growth-could-fall-50
NonScientist says
re #213, confused
” Hot water currents, like the Gulf Stream, carry warm water from the Equator toward the poles; when the warm water arrives around Greenland, it sinks. “If there’s a whole bunch of freshwater, it won’t want to sink…”
As my handle states, I’m no expert on this subject. I can’t understand how the above can be true.
Cold water should be denser, unless it’s right about freezing, such as ice –> meltwater and ii) at least the Arctic and now it seems the Antarctic are melting.
So
i)HOW can “warm water arrives around Greenland, it sinks” be true and
ii) how is more melting causing the Gulf current to sink less rather than more?
Mr. Know It All says
222 – NonScientist
I’ll take a shot at it. Sea water is more dense than fresh water because it contains dissolved salts. The warm Gulf Stream sea water moves on the surface of the ocean as it heads north, and as it heads north, it cools to the increasingly colder atmosphere. After it’s gone far enough north, it cools enough that it is now more dense than the water just below it, so it dives down into the ocean. However, with a warmer climate due to global warming, as the Gulf Stream goes by Greenland, it is mixed with more fresh water from melting glaciers than before warming occurred. The mixed Gulf Stream + fresh water is less dense than sea water because it is less salty. Thus, it stays on top of the ocean, does not dive down, and that shuts off the Gulf Stream. Al Gore explained this in his movie, “An Inconvenient Truth”.
Grade me – see how I did:
https://www.scientificamerican.com/article/earth-talk-getting-fresh/
Here’s Al Gore explaining it in his movie: (3 minutes)
https://www.youtube.com/watch?v=02NRKzemXYE
Here’s another short video on it:
https://www.youtube.com/watch?v=vGBaL3udkHI
Ray Ladbury says
NonScientist,
Whether water sinks or rises depends on its buoyancy, which in turn depends on its density. Seawater density depends mainly on its temperature and salinity. Warm water evaporates more than colder water, so its salinity increases. When it reaches polar regions, it cools, and the additional salinity is sufficient to raise its density above that of the surrounding water. Hence it sinks.
Ice water is fresh, so it dilutes the salinity, resulting in the Gulf Stream water remaining near the surface. This reduces the subsequent flow of the Gulf Stream, decreasing heat transport to the pole.
Look up thermohaline transport or global ocean current models.
MartinJB says
Here’s a (to me) new front in attacking conventional climate science: N2 and O2 are actually greenhouse gases too!
I first ran into this curious claim in the comments section of an article on climate change on FT.com. A comment by someone using the handle “Galileo’s Revenge” (of course, eye-roll) insisted that Raman spectroscopy shows that N2 and O2 also absorb in IR and that he was about to publish on the topic. Seemed a pretty obvious misunderstanding of how Raman spectroscopy works, and after explaining this I dismissed it.
And then just yesterday, someone on Facebook used this link (http://www.academia.edu/37577750/Quantum_Mechanics_and_Raman_Spectroscopy_Refute_Greenhouse_Theory) to suggest that our understanding of global warming was based on a fundamental misapprehension about greenhouse gases. I do believe the author of this “paper” is the same Galileo’s Revenge I ran into.
So there you have it. Raman spectroscopy (Which evidently no-one who has ever thought about climate change ever bothered to look into before… /HEAVY sarcasm) destroys the very underpinning of our understanding of global warming! /Even HEAVIER sarcasm
Kevin McKinney says
KIA, @221–
No, the US is not the champion, in general, of reduced CO2 emissions. Yes, it apparently had the biggest absolute reduction in 2017:
But famously, “one swallow does not a summer make”–nor does one year suffice to characterize a nation’s emissions trajectory.
Let’s start by quoting a little more extensively from the IEA report:
So the UK’s decrease was over 7x larger in percentage terms, and the relative long-term decline in CO2 emissions massively more significant–the US isn’t anywhere near its 1960 emissions levels. Mexico actually did a tad better than the UK:
Japan’s decline was also about 0.5%, so if we were giving Olympic-style medals based on relative emissions declines, Mexico would get the gold with the UK close behind for silver, and the US and Japan well back in a tie for third.
Now, let’s consider the statement that “Emissions in China and perhaps India are exploding.” The IEA report says that:
This is a little equivocal, but does not suggest ‘exploding emissions,’ especially when we consider that in recent years Chinese emissions had been pretty flat. If you consider the long term, and the structural changes in the Chinese energy economy that are occurring, it would seem that the Chinese economy is most likely in the process of plateauing. See for example this graph:
https://data.worldbank.org/indicator/EN.ATM.CO2E.KT?locations=CN
Clearly, emissions in the last several years are not behaving as was the case from ~2000-2010.
As to India, the IEA report says this:
Nothing equivocal about that–per the IEA, there’s nothing ‘splodey’ about Indian emissions over the last year or two. Like China, there is a structural transformation of the energy economy underway, with large numbers of coal plant projects cancelled, and large deployments of renewable energy coming instead.
Turning back to the European Union, it is true that 2017 was not a good year for emissions results. But that begs a little context. Here’s what the IEA folks have to say about that:
So the 2017 increase is not typical (though obviously it is unwelcome).
What about the long-term record? It’s shown here (unfortunately, several years out of date–if someone has a more up-to-date version, that would be nice):
https://www.c2es.org/content/international-emissions/
Since 1990:
–The gold medal for emissions reduction would go to the Russian Federation, whose emissions are down ~50%. Too bad about the economic collapse, though.
–The silver goes to the European Union, whose emissions are down ~20-25%.
–The bronze goes to the US, whose emission are up, but just slightly, from 1990 levels. (Hmm, maybe not quite as much manufacturing got offshored as is sometimes assumed.)
Of course, Chinese emissions really did ‘explode’ in the early part of this millennium, and are up something on the order of 300% since 1990. India’s increase has been slower and more gradual, but nevertheless has amounted to something like the relative increase seen in China, though from a much lower baseline level.
For more accurate estimates, if anyone cares enough, one could consult this:
https://data.worldbank.org/indicator/EN.ATM.CO2E.KT?locations=CN
If you hover above the graph trace, the value for the year will appear, so you can calculate precise increases.
For instance, selecting the India case (’cause I’m curious), you find that the 2014 emissions were 2,238,377 kt, whereas back in 1990 they clocked a mere 619,154. That puts the increase at ~361%.
https://data.worldbank.org/indicator/EN.ATM.CO2E.KT?locations=IN
Good thing there are some signs of change; were past Indian (quasi-exponential) trends to continue, we’d all be well and truly screwed. Even now, there’s reason for serious concern.
Oh, heck–one more from that site. Here’s the head-to-head between the US and European Union, since 1960:
https://data.worldbank.org/indicator/EN.ATM.CO2E.KT?locations=US-EU
Kind of a dramatic difference since 1982. Maybe the Kyoto Accord wasn’t such a failure, after all!
Mal Adapted says
NonScientist, I’m sure you’ll get lots of responses from actual experts, but my understanding is that the warm water of the Gulf Stream becomes denser as it cools and evaporates on its way northeast at the surface. Because density increases with both cooler temperatures and higher salinity, when the GS water reaches the vicinity of Iceland it sinks to the bottom. Greenland meltwater, even at 4 degrees C, is less dense, so that if it floods the North Atlantic the downwelling is interrupted, and the Gulf Stream grinds to a halt.
Mal Adapted says
NonScientist, I’m sure you’ll get lots of responses from actual experts, but my understanding is that the warm water of the Gulf Stream becomes denser as it both cools and evaporates on its way northeast at the surface. Because density increases with cooler temperatures and higher salinity, when the GS water reaches the vicinity of Iceland it sinks to the bottom. Greenland meltwater, even at 4 degrees C, is less dense, so that if it floods the North Atlantic the downwelling is interrupted, and the Gulf Stream grinds to a halt. Bummer.
mike says
at 222: let me google that for you:
https://www.hakaimagazine.com/news/greenland-ice-melt-could-push-atlantic-circulation-collapse/
decent primter on AMOC and Greenland melt. Of note, from the article:
“The effect of Greenland ice melt has not been widely included in previous studies of the AMOC because ice melt predictions are generally not included in climate models.”
and:
“Also complicating matters: scientists don’t fully understand the AMOC itself and how it might respond to not only an influx of fresh water, but also to shifting winds, rising sea levels, and changes in atmospheric and ocean temperatures.”
One word I would have for non scientist with his question about water temperature and how the streams flow and circulate is “salinity.” The flow is affected by many factors, but when you are considering what happens to the amoc near Greenland, you have to pay attention to the fact that Greenland ice melt delivers cold fresh water to the Labrador Sea and North Atlantic. I think that’s correct and accurate, but others will let us know if I have details wrong or have missed something big.
Google is your friend.
Cheers,
Mike
Hank Roberts says
LMGTF: https://www.google.com/search?client=firefox-b-1-d&q=how+does+thermohaline+circulation+work
Hank Roberts says
https://www.sandiegouniontribune.com/opinion/letters-to-the-editor/sd-military-climate-change-concerns-trump-denier-utak-20190127-story.html
San Diego (CA) Union-Tribune
Wednesday, January 23, 2019
OPINION
The awkward dance between Trump and the military over climate change
Hank Roberts says
https://www.space.com/40006-space-radiation-worse-than-expected.html
S.B. Ripman says
Lately the denialist choir has been singing a song that goes something like this:
Warm weather isn’t new,
We have an example for you,
Pay attention you alarmists,
What we say is quite true.
From the oughts to the forties,
The world warmed a lot,
From the forties to the seventies,
Not so much (earth didn’t get hot).
Sure there’s a rise after the seventies,
With that we agree.
But compared to the first one,
It’s just a matter of degree.
Calls for action are premature,
More proof needs to be found.
Who today can really say,
That temps won’t again rebound?
This argument has many weaknesses, obviously, but the central premise is worth thinking about: that when global land temperatures are displayed graphically, there appears to be an unexplained “lull” or “pause” from about 1940 to 1970 … and the lull makes it look like temperatures shot up once and then stopped their rise for a long time, and are now shooting up again (and because the lull is unexplained, who’s to say a cessation won’t happen again, any time?)
But another perspective exists, namely, that there has been an underlying, steady and increasing temperature rise from 1900 on … but that the continuous trend was dampened somewhat during 1940 to 1970 by hazes and reflectivity caused by industrial and vehicular air pollution (prior to the clean air advances of the 60’s and 70’s). This perspective is counter-intuitive: that humankind’s air pollution was of benefit and cleaning up the air pollution was bad for the planet. (Isn’t this history cited in support of global warming solutions that involve reflective geo-engineering?)
Anyway, I just wanted to express annoyance at the unpleasing noises coming from the choir, and ask whether the air pollution argument carries much weight.
Kevin McKinney says
#222, NonScientist–
The description that Hank cited is clearly *very* “dumbed down.” In other words, I think it was probably meant to be indicative, not really descriptive in any full sense. And from what reading I did, I suspect that the matter is not yet fully clarified for anyone, scientist or not.
See, for instance:
https://link.springer.com/article/10.1007/s00382-016-3467-y
Clearly, it is complicated, with many competing effects to untangle. One thing it does say pretty clearly, though, is that lower densities at depth in the Labrador Sea–off Southwestern Greenland–have been measured during the peak times of the ‘cold blob.’ Hold that thought for a bit!
Retreating to things I do understand, more or less, there are 2 main factors at work in driving the circulation of seawater. One is temperature, the other, salinity. Over most of the temperature range, colder water is denser than warmer water, and saltier water is always denser than freshwater–typically about 2-3%. The latter effect is what makes the meltwater from Greenland or Antarctica want to create a less-dense ‘lens’ of freshwater floating on the top of the saltier seawater beneath. (It will, of course, gradually mix.)
It takes a fairly wide temperature swing–~30 C–to induce a comparable density change in water. Looking at sea surface temperatures using the climate reanalyzer, you can see the temperature patterns associated with the Gulf Stream. The the main branch (warmth) really doesn’t get anywhere near Greenland; rather it is manifest in a fan-like warm swathe across much of the western coastal waters of the North Atlantic, extending more or less from Portugal to the British Isles. (I.e., the waters off Portugal are at 15 or 16 C, those off northern Scotland at maybe 8 or 9 C–and those off New York, which is more or less at the same latitude as Portugal, at maybe 5 C.) So the density swing associated with that cooling isn’t much.
But the Gulf Stream water isn’t just warmer; it’s saltier, too, since its surface has been subjected to high evaporation rates during its genesis in the tropics. So at some point the density overcomes temperature, so to speak, and the water sinks.
For the Gulf Stream the main ‘trunk’ is as I described it above, running from North American east coast to Europe. But there is an offshoot that diverges toward Greenland, creating an area of ‘deep water formation’–an area where this sinking occurs–southwest of Greenland. That’s the area they focus on in the paper I linked above–the area where the density decreases at depth were measured.
____________________________________________________________________________
That’s where things start to get uncertain for me. If you imagine the ‘lens’ of cold, fresh water as fairly discrete in comparison with the saltier Gulf Stream water, then you imagine the latter tending to dive under the former. But that would imply enhanced deep water formation, while Hank’s citation asserted the opposite–that is, *inhibited* deep water formation.
So, what if the water masses tend, for whatever reason, to mix? Presumably, you’d end up with a much thicker (deeper) layer with a much more gradual gradient profile. It might make sense that that setup could work against current strength.
And if the speed of the current drops, then less heat is being advected into the area, and the area will tend to cool. Likewise, salinity–if less salt is being advected in on average, then salinity, and therefore density, would presumably tend to drop, too.
So it might seem as if there is a potential feedback tending to stabilize the lower deep water formation setup. But all of that stuff below the line is really just speculation on my part.
Carrie says
PHOENIX—Leading climate scientists and meteorologists are banking on a new strategy for talking about climate change: Take the politics out of it.
That means avoiding the phrase “climate change,” so loaded with partisan connotations as it is. Stop talking about who or what is most responsible. And focus instead on what is happening and how unusual it is—and what it is costing communities.
That was a main takeaway at the American Meteorological Society’s annual meeting this month, where top meteorologists and environmental scientists from around the country gathered to hear the latest research on record rainfall and drought, debate new weather prediction models and digest all manner of analysis on climatic mutations.
https://www.politico.com/magazine/story/2019/01/27/climate-change-politics-224295
Yes, well OK. Denial, obfuscation, playing word games, and outright dishonesty might help. Or it won’t.
Carrie says
Up-to-date weekly average CO2 at Mauna Loa
Week beginning on January 20, 2019: 411.99 ppm +3.68 ppmv
Weekly value from 1 year ago: 408.31 ppm
https://www.esrl.noaa.gov/gmd/ccgg/trends/weekly.html
Oh, is that all? Daily’s back down at 410 to 411.
Unlikely to last very long before rising again to the 413s.
Al Bundy says
Once the warm water subducts it is no longer subject to evaporation and is subject to dillution so if it isn’t dense enough to hit bottom yet it probably never will be. The gyre will still go round – coriolis makes it go – but the northern leg that feeds the overturning current and warms the northern part of Europe can slow or stall. Does that slow Greenland’s melt, resulting in a stuttering pattern, perhaps in tune with the NAO? Dunno. Water is heavy and so has a lot of momentum. Changing a current has to be harder than turning a supertanker…
Ray Ladbury says
Hank@232,
I think that some of the nuance in that piece got garbled. Any time you have low solar activity, you will have increased galactic cosmic ray flux. The previous solar minimum was the wimpiest of the space era. It was deeper and lasted longer than any we’ve seen in the past 70 years. As a result GCR fluxes were 8-20% higher (depending on particle type). The Solar Minimum we are just entering looks as if it will be similarly wimpy, and the Solar Maximum just completed was quite wimpy as well, with relatively few big solar particle events.
Galactic cosmic rays are a significant concern for several reasons. They are more likely to cause electronics to malfunction (single-event effects), and they also cause more serious damage to DNA, due to their high energy and ionization potential. They’re also nearly impossible to shield against.
Solar particle events, which are generally more likely when the sun is more active are generally short term distrubances–a few days to a week or so. However, they can resulty in pretty high doses over those periods. One of the biggest measured solar events hit roughly midway between the Apollo 16 and Apollo 17 missions, and could have represented a serious threat.
NonScientist says
@ responses to #222
Thanks to all for your responses. I ask these questions bc I now have cognitive decline and need to digest information in quite small bites.
Carrie says
The Bureau’s ENSO Outlook has therefore moved to El Niño WATCH, meaning there is approximately a 50% chance of El Niño developing during the southern hemisphere autumn or winter.
While most climate models indicate ENSO-neutral conditions for the immediate future, the current ocean warmth and likelihood of ongoing warmer than average conditions mean the risk of El Niño remains. Three of eight models suggest that El Niño may establish by mid-2019.
Feel free to check any official MET/ENSO info website.
Maybe another mass bleaching event could raise it’s head on the GBR and other southern reefs before too long.
Didn’t take more than 2 days for MLO CO2 to “skyrocket” back to +411 again
January 29: 411.24 ppm
January 28: 411.60 ppm
January 27: 410.96 ppm
January 26: 410.96 ppm
January 25: 410.00 ppm
More 413s right around the corner. Am curious what May 2019 will produce at MLO and Globally. I’ll just have to wait till the numbers come out.
Roger Sibley says
Are their any indications that sudden stratospehric warming has over time increased the heat radiated from the top of the atmosphere ?
As a lay person who takes a keen interest in following climate science I am wondering if this can be visualised as a negative feedback by the climate system burping some of the excess anthropogenic heat away.
Russell Seitz says
235
Concluding an admonition to depoliticize something with a link to Politico often ends as badly as predicting that the world will end before you leave the White House.
https://vvattsupwiththat.blogspot.com/2019/01/its-end-of-world-as-we-know-it.html
Al Bundy says
A study figured the deaths due to the Americas’ depopulation and linked the answer (perhaps 50 million) to ice core data…
“and what we see from this study is the scale of what’s required, because the Great Dying resulted in an area the size of France being reforested and that gave us only a few ppm. This is useful; it shows us what reforestation can do. But at the same, that kind of reduction is worth perhaps just two years of fossil fuel emissions at the present rate.”
https://www.bbc.com/news/amp/science-environment-47063973
Hank Roberts says
https://www.cbsnews.com/news/giant-hole-in-antarctica-thwaites-glacier/
Called it: https://www.realclimate.org/index.php/archives/2015/06/unforced…june…/comment-page-6/
… That’s what I called the “Ice Cube Catastrophe” scenario — a sudden rumble, the ice cap becomes crushed ice and rushes to the sea….
Ron R. says
Mal Adapted, #694 on Forced Responses (I’m replying here because the dialog box is gone from that lengthy thread, maybe because of the new month). A good article by Jared Diamond. His comments re:population are right on. His summary, “Forced to choose between limiting population or trying to increase food production, we chose the latter and ended up with starvation, warfare, and tyranny.” So true. Yet we’ve also got something else to show for this millennial long experiment in agriculture and population growth – art, science and technology. True he does say, “While post-agricultural technological advances did make new art forms possible and preservation of art easier, great paintings and sculptures were already being produced by hunter-gatherers 15,000 years ago, and were still being produced as recently as the last century by such hunter-gatherers as some Eskimos and the Indians of the Pacific Northwest.” Yet that’s a bit shallow compared to what modern people have accomplished in these areas. Those pre-modern art items are, by contrast, valuable mainly because they exist at all.
If I were prone to wild speculation, and I am sometimes, I’d say that if there’s anything to causation, it might be that we were meant to go down the agricultural/population/development path just so we could create these things- art, music, science. But that now that we have done so, and are on the edge of AI (which can much better simulate Julian Simon’s ‘the more heads working on a problem the better’ doctrine) which can continue that progression, our growing human numbers are no longer justified, and, in fact, as everything now indicates, are a serious threat to the existence of the biosphere. A confluence of factors thus indicates that it’s time to scale back, and combine the best of both worlds: the primitive and the modern.
Al Bundy says
Russell,
Actually, AOC is correct. The world AS WE KNEW IT is dying right now. Yep, there will be a “new” world no matter what humans do. But AOC is correct even if she’s too young to realize that “old age and treachery will beat the truth every time”.
Caveat, AOC, caveat because R______ has NO interest in truth, but is solely interested in being “proven” correct via, well, figure it out, guys.
Radge Havers says
…Mal…Kevin…
Now you’ve done it. Forced me to comment against my will and better judgement.
So just as a thought experiment, if you kill off your brain cells one by one, at what point does your (completely undetectable) ectoplasm exit your body for more promising haunts, leaving behind a corporeal husk that is religiously dead?
My understanding is that synapses either excite or inhibit rather like fuzzy switches that have evolved (as you might expect: cause and effect leading to cause and effect) in a large, complex open system that provides sufficient, sustained energy. Eventually such an environment should create ever more efficiently functioning brains that become inclined toward seeking reality-based, novel substrates upon which to grow and reproduce –to become interested in science and to visit sites like RealClimate, seeding it with provocative if occasionally OT musings. No?
By my Ka and my Ba, dj ‘ankh mj R’ djet!
Hank Roberts says
Hmmm, above is a bad link. Try this:
https://www.google.com/search?client=firefox-b-1-d&q=site%3Arealclimate.org++the+%E2%80%9CIce+Cube+Catastrophe%E2%80%9D+scenario