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MA Rodger at 18:28 PM on 5 June 2019Effects of Global Warming
William @9,
Picking up on your "what are we going to call the 2.75 million year period" question, I'm not sure what prompted it. Your preceeding sentences sound perhaps a bit accusative and if so, perhaps you mis-read the OP that actually mentioned "cold periods (so called Ice Ages)" over the past 800,000 years.
The period prior to the Holocene and back +2½million years does have a name, the Pleistocene and it is a period of 'ices ages' and 'interglacials'. The characteristic that makes it different to the periods before was the preceeding formation of the Panama Ismuth and the subsequent arrival of (or perhaps the more extensive arrival which Knies et al 2014[PDF] appears to show) permanent polar ice in the Northern Hemesphere, particularly the Arctic Sea Ice. In light of the permanence of NH ice through the Pleistocene (it apparently didn't disappear in the Eemian, for instance see Stein et al 2017) I think the arrival of ice-free Arctic summers for the first time in millions of years is a strong scientific message that has yet to be wielded properly.
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scaddenp at 12:43 PM on 5 June 2019CO2 is just a trace gas
Not sure that "emitting particle" is right, but radiation spectrum is absolutely dependent on temperature. And, yes, you can use the theory to predict spectrum of radiation at TOA or at surface of earth, or by how much the spectrum should change if you increase say CO2 from 400 to 440ppm. These have all been done (eg here) and predictions match observations with exquisite accuracy (a fair bit of advanced tech depend on these equations being correct).
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Rovinpiper at 12:33 PM on 5 June 2019CO2 is just a trace gas
I see.
So, tell me. Doesn't the spectrum of emitted radiation depend on the temperature of the emitting particle?If that is the case, then doesn't it provide a pretty convenient test of this theory?
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Doug_C at 11:49 AM on 5 June 2019Effects of Global Warming
I also think it is far past the time to keep letting free market forces determine the energy model we use. From all the evidence if energy policy isn't controlled and guided at a global level then we face catastrophic conditions on Earth that make free market economics or any thing else human related moot. Because we keep doing what we're doing much longer then there will be no people left.
I think there need to be hard targets imposed on the energy market that have a 50% reduction in fossil fuels use by 2030 and a 100% by 2050.
This would require somthing like much safer and hihgly efficient Gen IV nuclear power to be implemented on a large scale in conjunction with renewable energy.
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TVC15 at 10:54 AM on 5 June 2019Climate's changed before
Thanks again MA Rodger @ 724
The deniers worship the US climate denier blog sites such as WUWT. It's ridiculous what that site puts out. The US also has the Heartland Institute whose mission is to instill doubt in American minds about the science of climate change than the Heartland Institute.
This is a tyical US denier rant:
"Hot places get hotter in the summer. Weather is not climate, but climate changes naturally due to the Sun, and other factors. If you want to live like a Stone Age Stooge, plus pay exorbitant prices for energy and ALL products and services, be my guest, but don't force others to follow your cult like religion to make yourself feel relevant in the Universe."
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TVC15 at 10:44 AM on 5 June 2019Climate's changed before
Thanks MA Rodger @ 724
The climage deneir was the one who made this statment: And as you know, nature's impact on climate can and has been EXTREME prior to man, and man's industrialization. How do you account for that?
In my orgional post I had it indented so others would know this was not my statment.
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TVC15 at 10:41 AM on 5 June 2019It's the sun
Thanks [PS]!
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Doug_C at 10:41 AM on 5 June 2019Effects of Global Warming
Ger @11
That's probably for the current light water reactors, I'd be really interested to see what the numbers are with MSFRs when they finally get one up and running. With only a fraction of the concrete needed for secondary containment with a light water reactor they should sharply cut the initial carbon output and with the much higher fuel efficiency and greatly reduced waste stream the operational and end of life costs and footprint are probably going to be much smaller.
Instead of large batches of degrading fuel rods being removed every few years as with light water reactors they would be pulling fission products constantly out of solution from an MSFR and either storing them onsite or selling some of the fission products such as medical radioisotopes or xenon to the aerospace sector where it is used as ion rocket fuel. And with very little TRUs the long term waste costs and footprint is also going to be a fraction of current costs with LWRs.
One thing that will be an issue is the meter thick steel neutron reflectors that after several decades of operation are going to be a radiological hazard for decades as cobalt-60 has a half life of 5.6 years.
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Ger at 08:35 AM on 5 June 2019Effects of Global Warming
@Nigelj, @Dougc:
Comparison of the GHG footprint of several generation techniques can be found en.wikipedia.org/wiki/Carbon_footprint. Nuclear at 60~65 gCO2-eq/kWh, wind power at 21 and PV solar at 106. I've seen other studies setting Nuclear at 24~85 (mining exclude/included) Windpower 8~30 (recycled-new) and PV 20~80 (production techniques, mining) and also biomass IEA report with carbon negative outcome of -9 g CO2-eq/kWh, presumably from sustainable forest with more growth than extraction. As a note: LCA includes demolition costs of the installation after it's lifetime. Now I have seen that for PV, Wind power and biomass powerplants all on lifetime expectancies of 20~30 years including derating. For coal fired plants that period is taken to be 50 years. There is no derating for coal fired as that is maintained to be at top capacity. I wonder if that is realistic. For NPP the minimum I've found is 60 years and very wide margin for the costs: not enough experience. I would say take the costs of a Fukushima till now and you will not make a big mistake: even in case a NPP is shutdown, it will take a 35 years before one can think of taking it down. And all used fuel in place will be active for another 100 years.
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Doug_C at 07:02 AM on 5 June 2019Effects of Global Warming
william @9
Correlation does not equal causation. Just because humans were present in the Americas when the megafauna went extinct is not evidence that they were the cause of this extinction.
What Killed the Great Beasts of North America?
"The idea that humans wiped out North America’s giant mammals, or megafauna, is known as the “overkill hypothesis.” First proposed by geoscientist Paul Martin more than 40 years ago, it was inspired in part by advances in radiocarbon dating, which seemed to indicate an overlap between the arrival of the first humans in North America and the demise of the great mammals. But over the years, a number of archaeologists have challenged the idea on several grounds. For example, some researchers have argued that out of 36 animals that went extinct, only two—the mammoth and the mastodon—show clear signs of having been hunted, such as cuts on their bones made by stone tools. Others have pointed to correlations between the timing of the extinctions and dramatic fluctuations in temperatures as the last ice age came to a halting close."
If early human arrivals in the Americas killed off some of the megafauna why did they then stop and allow massive numbers of other quite large species to remain like the Bison, Grizzly Bear, Musk Ox and others.
The rapid fluctuations in climate at the end of the last glaciation period and the extinction of species that lost their associated habitats is likely evidence of how dangerous climate change can be to life.
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william5331 at 05:54 AM on 5 June 2019Effects of Global Warming
If we are going to call the recent icy period an Ice Age, which extended between the Eemian interglacial some 125 thousand years ago and the present Holocene interglacial then what are we going to call the 2.75 million year period in which there have been more or less 40 cycles between ice and not much ice. I don't care what we use as long as we use it consistently. It is not just semantics. Some folks, even a program on National Geographic, suggested that the fauna of North America died out because of the climate change at the beginning of the present Holocene interglacial. Nonsense. These animals had survived multiple cycles in fine fettle. The only difference was the advent of man into the Americas. Terminology, especially in science, is important.
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Doug_C at 05:01 AM on 5 June 2019Effects of Global Warming
We are suffering from institutional cognitive dissonance here in Canada.
The newly elected Alberta government where oil and gas production is considered sacrosanct has declared an intention to create a $30 million "war room" to attack anyone threatening the fossil fuel sector in Canada.
Environmental groups shrug off Jason Kenney's 'war room' threat
While significant regions of Alberta are currently under emergency measures due to climate change driven wildfires. They are sending firefighters from across Canada to deal with a climate change driven emergency in Alberta that will only get worse as industry and government there do almost anything to protect the oil and gas sector.
B.C. sending more firefighters to help battle Alberta wildfires
This is highly irrational as the Alberta government has been threatening BC economic interests for several years over the resistance to the Trans Mountain pipeline expansion plan.
UCP poised for battle with B.C. over Trans Mountain pipeline expansion
So while BC is treated as the enemy when we don't bow to pressure to not just maintain current levels of fossil fuel use but expand them, when climate change emergencies that have been predicted for decades are in fact now happening we are also expected to respond to the provinces that are driving this sector over all reason.
Federally the Green Party leader of Canada has declared she also supports fossil fuel use for decades as long as we don't import any of it.
Elizabeth May wants to only use Canadian oil — a plan Quebec's Green Party leader can't support
It's not like there isn't awareness at the highest levels of the crucial need to phase out fossil fuels, the Canadian government signed the 1997 Kyoto Protocol to phase out fossil fuels and then again in Paris in 2016.
But when it comes time to actually enact policy to do this, government after government balks and the private sector pretends there is no crisis.
While investment in alternative energy has been very low in Canada for years, investment in fossil fuels is still massive here.
Canada’s major banks have financed $464 billion worth of fossil fuel projects since 2016.
What do we as citizens do when the private sector that obviously wants oil and gas use no matter the catastrophic impacts uses part of the proceeds of their business to effectively control policy.
Life is dying on Earth while conditions for people are becoming very dangerous as well as with some of the deadly wildfires in California, Australia and other places. We are lucky we have not lost people here in BC with how critical our wildfire situation has become. In a month or so we probably won't have the firefighting resources to share with other regions when our fires start catching.
Anyone who is still claiming this make sense in any context is totally delusional, we get off all these highly polluting fossil fuels as fast as possible or we in fact do face the horrific prospect of an unlivable world in what is in geological time the blink of an eye.
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Doug_C at 02:02 AM on 5 June 2019Effects of Global Warming
nigelj @5
That is what is needed. A comprehensive breakdown comparing the relative resources that go into making and running a 1,000 MW MSFR nuclear power plant as opposed to how many wind turbines, PV solar panels, tidal generators, etc... are needed to provide the same energy production and what overall ecological impact they both have.
As for weapons proliferation which is a serious concern, the thorium fuel cycle in molten salt reactors effectively addresses this concern. Once the reactor is in operation it needs new fissile material added to it as the initial charge of either U-235 or U-233 is used up by fission. The reactor core would have a blanket loop surrounding it of molten salt with the thorium in solution. The neutron flux from the core fission reaction provides just enough neutrons to keep the core fission reaction going and breed new fuel from transmuted thorium in the blanket, it's a little over a 1-to-1 ratio.
If you start taking out the new U-233 from the Th-232 that has just been transmuted then there is no new fuel to keep the molten salt reactor in operation. Th-232 is also seven neutron captures away from weapons grade Pu-239 while U-238 is only one neutron capture away making uranium the preferred fuel cycle for weapons creation.
A MSFR would be producing about 0.159 kgs of Pu-239 a year while a light water reactor would produce about 110 kgs in that same time period.
Why the molten salt fast reactor (MSFR) is the “best” Gen IV reactor
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John Hartz at 00:09 AM on 5 June 2019Climate's changed before
I accidently deleted the following comment. My bad.
TVC15 at 19:59 PM on 4 June 2019
Is there an easy answser for this question being asked by a climate denier?
And as you know, nature's impact on climate can and has been EXTREME prior to man, and man's industrialization. How do you account for that?
So far from what I've learned from you guys is Earth's orbit, solar output, the sun being cooler, greater volcanic activity, rock weathering, surface ice albedo, massive amounts of Dinosaur gas? (sorry guys I had to toss that in for grins)
Are there other factors I missed?
Thanks!
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MA Rodger at 23:56 PM on 4 June 2019Climate's changed before
TVC15 @724,
There were of course "EXTREME" climate processes prior to mankind arriving on the scene. These can perhaps be classified into two different groups.
The first can include really big changes but they occur very slowly, although sudden on a geological time-scale. So the end of the last ice age saw a rise of perhaps 6ºC in global temperature over 8,000 years or 55 million years ago the PETM which saw similar temperature rises over 40,000 years (long enough for, for instance, horses to adapt to the temperature increases by slowly evolving from pony-size into the size of large dogs).
The second group are far more sudden, the suddenness often obvious. A big volcanic eruption (Mt Toba 74,000 years ago), a meteor strike, or a sudden influx of fresh water that destabilises ocean currents (as per Dansgaard–Oeschger events). This second group can still have very very big local effects but obvious causes that soon dissipate (althugh D-O events can take 2,000 years to return to the prior climate).
But in all this, I'm not sure what a denialist is trying to argue. If we wait long enough there will eventually be a mega-volcano blow its top, or a big meteor will eventually strike the Earth. (There isn't enough ice about for a D-O event to occur without an ice-age.) So is the denialist suggesting we set about creating our own climatic disaster to allow us to practise for how to respond to the real thing? Or does he want an explanation for every wobbly bit of paleoclimate before he will accept the blindingly obvious fact that it is humanity driving todays warming climate and it will not end well if we don't do something about it?
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peter7723 at 22:53 PM on 4 June 2019Effects of Global Warming
This is an excellent summary of the symptoms of the illness.
However, for remedial action to be taken, the question to be answered is "What should we do?". Answers include "Reduce CO2 in the atmosphere", "Eliminate emissions of CO2", "Eliminate emissions of methane". But, these are too general to lead to action.
The questions in turn give rise to "How?" For example, "How can CO2 in the atmosphere be reduced?" with answers such as "Carbon sink", Carbon capture and storage", "Filter CO2 and water from the air and convert to oil" (https://www.nature.com/articles/s41467-019-09685-x), "Remove carbon from hydrocarbons before burning" (https://www.newscientist.com/article/mg23230940-200-crack-methane-for-fossil-fuels-without-tears/). Each of these have advantages and disadvantages and give rise to lower level questions.
We must carry such analyses through to actions that people can see make sense. "Climate Emergency" by itself is so abstract and frightening. -
TVC15 at 19:41 PM on 4 June 2019It's the sun
Hi Daniel @ 1262
Would you mind explaining how scientists differentiate between human generated and nature generated CO2?I've found that there are two different isotopes for the human imprint vs. natural CO2.
Are there other methods besides the identifying the different isotopes and what methodologies are used to test these different contributors?
Thank you!
Moderator Response:[PS] that would be offtopic here. Please see this rebuttal for two other methods used to constrain CO2 origins.
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nigelj at 19:03 PM on 4 June 2019Effects of Global Warming
Doug @4, I know what you are saying: A single reactor building producing 1000 mwatt intuitively seems to use less materials than a big solar or wind farm of equivalent output. However it would be useful to see a hard data comparison, because appearances can sometimes be deceiving. And the sciency types on this website would rightly insist on it. I do think it would be a good argument in favour of nuclear power if you are correct, so its interesting.
Molten salt reactors are still somewhat experimental. I agree they have many advantages, although one sticking point is the ability to produde high grade nuclear weapons materials. Its this sort of thing that is slowing development down. In the meantime we obviously have to build what is feasible like solar and wind power. We are lucky we have geothermal power.
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Doug_C at 18:15 PM on 4 June 2019Effects of Global Warming
nigelj @3
The scale of it just doesn't seem right for low density renewables. If as the data says nuclear power has several billion times the energy density of energy sources such as solar and wind power and it would take about 15,000 1,000 MW nuclear power plants to totally replace fossil fuels, wouldn't that require several trillion comparable renewable energy sources.
We're talking about a huge amount of energy needed to replace all fossil fuels and finite resources, space and time to do it.
As for nuclear power, my point about the actual biological response to ionizing radiation in most dose rates anyone will be exposed to is that the requirements placed on nuclear power for nearly zero levels of emissions are part of what makes it so costly.
And we couldn't go with "conventional" light water reactors now anyway as a replacement to fossil fuels because the industrial base to build the thousands of massive stainless steel primary containment vessels simply doesn't exist.
What is being proposed by some is the molten salt fast reactor concept that does away with the need for massively strong primary pressure reactor vessels and the need for equally massive secondary containment in the chance there could be a catastrophic loss of radioactive collant.
Why the molten salt fast reactor (MSFR) is the “best” Gen IV reactor
With a molten salt reactor your primary containment is chenical as the fissile material is held in solution in the molten salt. The reactor is not under pressure and there is no chance of a melt down. The core is already molten.
We know the concept works as ORNL ran one for several years in the 1960s and worked out much of the chemistry and materials issues.
Molten-Salt Reactor Experiment
A fast molten salt reactor simplifies the concept as it does away with the need for a core graphite moderator that needs to be changed every four years and simplifies fuel reprocessing.
They can also be built in modular design so you can have 300 MW moduls that can be conbimed to produce larger plants giving flexibility to implementation.
Waste is also greatly decreased with MSFRs as they produce a fraction of transuranics(TRUs) that are such an issue with light water reactors that use solid fuel rods that break down from exposure to heat and neutron bombardment in the core and become less stable due to the buildup of fission products over time.
You get an almost complete burnup with a molten salt reactor so almost all your waste is short lived fission products that can be safely stored onsite as has been done for decades with the current light water reactors.
Molten salt reactors also use a gas parging system that makes it possible to pull fission products out of the core salt unde4r operation that might interfer with the stable running of the reactor and some are highly valuable for things like nuclear medicine like Moly-99 used in imaging, Iodine-131 and bismuth-213 used in cancer treatment.
MSFRs also produce small amounts of Pu-238 used as a power source for deep space mission and ample xenon with is fuel for ion rockets in the space sector. They also produce noble metals like gold, silver and platinum.
There's so many advantages to MSFRs and once the infrastructure is created to begin large scale production the cost would be a fraction of what nuclear power now costs.
I think it's the way to go for many reasons.
Another is running thorium in molten salt reactors also produces little fissile materials that can be used in weapons manufacture. It is nearly a 1-to-1 ration of fissile material undergoing reaction in the core to thorium in the blanket being converted to U-233 by the neutral flux being produced by the reactor. Take out the new U-233 and the reactor stops running for lack of replacement fissile material.
As I said it's a question of scale. And if thousands of reactors in the 1,000 MW range are required to phase out all fossil fuels and nuclear power has billions of times greater energy density than renewables then a comparable renewables energy model will require trillions of comparable facilities dispersed over large areas of the Earth.
It's still possible to implement solar, wind, geothermal, tidal, etc... energy under a nuclear power replacement regime, it just make it so the scale of that part of the model can be greatly reduced.
As for economics, we will be creating an entirely new economic model to reflect the new energy model. At its basis any economic model must include a viable biosphere to take place in. And then build out from there.
And the best way to acheive that is to use the most efficient sources of energy that use the least amount of finite resources and take up the minimum amount of space that otherwise could be part of a viable ecosystem with sufficient biodiversity indefinitely.
Nuclear power in the form described above would seem to fit that bill far better than low density renewables on the face of it.
Be interested to see that take others have on this.
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climate_watcher at 17:58 PM on 4 June 2019Roy Spencer on Climate Sensitivity - Again
Another Roy Spencer blog post on this topic, posted in our group for climate change news.
http://www.drroyspencer.com/2018/04/new-lewis-curry-study-concludes-climate-sensitivity-is-low/?fbclid=IwAR2EU3mgUfELyXzhXEiznTlXGTeMwVK7rV9ZS7jkt-L3kTPo0u9_XWR1bJw -
TVC15 at 17:55 PM on 4 June 2019Climate's changed before
@ RedBaron 721
Those are two truly encouraging links you posted about China and India dominating greening the earth!
Thanks for sharing this!
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TVC15 at 17:44 PM on 4 June 2019Climate's changed before
Hi RedBaron @ 721,
Trust me I am a scientist and I know science is based in evidence not faith.
In thinking about your first response to me with respect to the quibbling over which sector should take the heavier load...do you really think either one is going to simply agree to taking the heavier load? I don't. These two sectors have tons of money to buy any lobbyist or politician they want in order to fight against taking any load. And I'm certain there will be resistance from both sides. Thus this leads me back to it's too late to turn back now.
Just look at the current heat wave hitting India with those crazy high temps! Even with this news you still see the deniers in the US and around the globe.
I am not a doom and gloom type gal, just a realist.
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nigelj at 16:55 PM on 4 June 2019Effects of Global Warming
Doug_C @2, I agree with your first two paragraphs. The main issue with nuclear power is the economics. This is because our civilsation works on what is the most economic option to generate a desired outcome, and right now wind power is lower cost than nuclear power, and solar power is about the same (according to Lazard's analysis), so generators tend to prefer renewable energy, especially given the large scale of nuclear projects and complicated approval procedures.
The space taken up by renewable energy is just not significant, because solar power panels tends to be on building's roofs and can be deployed in waste land and in deserts, and wind tower pylons sit on farming land not taking up significant space.
Of course safety is a big concern as well as economics, and I recall reading something that suggested that radiation below a certain level is harmless and that the relationship is not linear. But nuclear accidents are a nightmare and very costly to clean up.
Resources are an issue to consider, but the world is not about to run out of important minerals not for many centuries yet, and even if we were things won't slow down because capitalism is like a voracious machine. Imho our main hope is smaller global population.
Given nuclear power is not exactly low cost it must use plenty of materials and (fossil fuel) energy in construction and mining those materials, so I'm not convinced its particularly low carbon in terms of manufacturing. Of course I do realise some of the costs are in scarce metals. But do you have some hard data comparisons on carbon content in manufacturing between nuclear power and the other options?
If thorium reactors become economic, and can be shown to have low carbon in the manufacturing process, great, I have no objection. Until then we have to work with what is plausible in the real world.
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RedBaron at 16:13 PM on 4 June 2019Climate's changed before
Don't digress because one is just a symptom of the other, and fixing one fixes both. And more importantly to your lack of faith, please remember. Science is about evidence not faith.
Soil Carbon Sequestration Potential for “Grain for Green” Project in Loess Plateau, China
Sure that paper just discusses potential. But in fact the project did go forward and has indeed suceeded in already restoring ecosystem function to vast acreage and is even now sequestering approximately 25% of China's emissions. The effect is so profound and widespread it can be seen from space.
Human Activity in China and India Dominates the Greening of Earth, NASA Study Shows
So you see? Where the highest human population density on the planet is also the most improvement in ecosystem restoration, which is actually already making significant strides in restoring ecosystem function over vast areas...
Now is not the time to give up with dispare. Now is the time to tighten your belts and get to work! We have a lot of work to do and pouting around with gloom and doom is not helping one bit.
We can do it. Get er done!
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scaddenp at 13:37 PM on 4 June 2019New rebuttal to the myth 'Holistic Management can reverse Climate Change'
Thanks for that. Quite a lot to digest when I get a little more time.
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Doug_C at 13:29 PM on 4 June 2019Effects of Global Warming
Climate change is already becoming catastrophic and everywhere researchers are looking life is being threatened far more than was thought even a few years ago.
Many insect populations are in critical decline, the same goes for avian populations and many others. It's not just climate change that is doing this, but global industrial society overall where there is no long range planning as short term profit making drives almost all economic activity.
I also seriously question that relying on low energy density "green" energy technology is going to prevent a catastrophic collapse of the biosphere in the near future.
They would need to be implemented on a vast scale to replace all fossil fuels and that would require equally vast resource extraction, transportation, manufacturing and construction.
There's only one shot to avoid a systemic collapse now is my take on this.
Nuclear power and one specific type, the molten salt fast reactor running the thorium fuel cycle.
If green renewable energy production can take up to 1,000 times the space - with all the attendant resouces to build it - of fossil fuels;
Renewable energy sources can take up to 1000 times more space than fossil fuels
And in turn nuclear power can have millions of times the energy denisty of fossil fuels.
Then that gives us an energy density of nuclear power several billions times that of green renewables. And where a lump of thorium that can fit in your hand will provide all the energy you need in a lifetime, the mass needed to provide energy from low density renewables - including the space dedicated to it - would be many tons that would crush you.
My question is, do we really have the resources and time to be so idealistic about energy production when the situation is now so critical. And when there are serious question about the actual physical response to ionizing radaition which is the main hazard with nuclear power.
If for instance if ionizing radiation may actually have a beneficial effect on people exposed to slightly higher levels of background radiation as the Nuclear Shipyard Workers study indicated.
Nuclear shipyard worker study (1980–1988): a large cohort exposed to low-dose-rate gamma radiation
And new research seems to indicate that within certain thresholds ionizing radiation isn't just harmless to people but it may in fact be essential to the normal functioning of our cells.
Is Radiation Necessary For Life?
I think it's entirely possible we have been avoiding the solution to many of our problems for decades for fear of something that has never been the risk it has been presented as since the mid 1950s that some researchers consider a scientific fraud for political purposes.
Just my thoughts, we can keep running in fear from something that always has been and always will be an intrinsic part of our being;
Or embrace what is likely our last shot at salvation at a species level. As I said, given the scale needed to implement low density energy production with the misconception it is clean when a vast amount of resources must go into manufacturing it and an equally vast amount of space must be taken up by it, I think going completely "green" is just as dangerous as fossil fuels energy production.
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nigelj at 13:01 PM on 4 June 2019Effects of Global Warming
This is a nice concise summary of all the important points. It might almost be an idea to put it under "IPCC facts " or something similar so there is a permanent link to it.
Another reason young people are becoming vociferous is perhaps because they see the double standards of adults who say there is a problem yet do nothing. It may also be because young people get some of the science at school, and are also not deluged with denialists rhetoric as much as adults are.
However one quibble. I'm not sure that climate change has become more political and partisan because the results of climate change are becoming more obvious. If it is I think you need to explain how, maybe I'm missing the point. If anything increasingly obvious bad weather may make it less political and partisan as it becomes harder to deny.
Climate change is more likely becoming more political as a result of America's culture wars that have complicated causes and have gained a life of their own getting worse and worse for no logical reason. An analogy might be the way WW1 developed and spiralled out of control, in an unstoppable sort of way.
It's unfortunate that the IPCC reports have not at least mentioned the possibility of multi metre sea level rise by 2100. If they have it's certainly buried away in the fine print.
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TVC15 at 10:39 AM on 4 June 2019Climate's changed before
Thank you RedBaron @ 719
To be honesty I have no faith in the human species. Overpopulation leading to humans crowding out and forcing other animal and plant species into extinction on top of the GHG emissions and all the other human activities that's destroying life on this earth is why I have bleak outlook on the human species.
I sometimes wish I did not know of all the mass destruction humans are causing. Climate change is just one in many things humans are contributing to.
I digress.
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RedBaron at 08:41 AM on 4 June 2019Climate's changed before
@TVC15,
Don't be so sure about that. While humans have huge destructive capacity, we also have tremendous creative capacity too.
You are right about just dropping emissions to zero won't be enough. That's been in the IPCC models all along. But the carbon cycle is just that...a cycle. There are two sides to balance. While reducing emissions can't work alone, the other side of the carbon cycle is sequestration. And it only takes about a 10% improvement on the natural carbon cycle sequestration side worldwide to offset emissions.
So while it is controversial still, we actually do have the capacity to improve the long term sequestration side of the carbon cycle at the same time as we reduce emissions. That means we actually can get to a drawdown scenario and it is not yet too late.
I wrote this up to show how:
Can we reverse global warming?
That gets us back to the IPCC scenario that stabilizes the climate! So no. It is not too late.
And there are more details regarding the emissions side of a drawdown scenario here:
And more information on how to properly set up a carbon market to facilitate both emissions and sequestration here:
Emissions is straight forward in a fee and dividend system. You put a fee on fossil fuel sources. That makes people search for low carbom alternatives, which are abundantly available already. The fee just makes them relatively cheaper. But then we take the dividend and use it to pay for measured verified carbon sink increases (rising SOC), and the two together can get us to a net negative.
There are still a few people quibbling over nonsense like which sector should take the heavier load. Should energy take 50% and agriculture the other 50% on the path to a drawdown scenario? Or should it be 80%/20%? Or maybe even 20%/80%? It really doesn't matter as long as in the end we get to a net negative atmospheric carbon flux.
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scaddenp at 08:37 AM on 4 June 2019Humans and volcanoes caused nearly all of global heating in past 140 years
Just one other further point. The milankovitch forcing for ice ages is very slow. At 65N (where the changes in solar insolation make the difference between summer melt or not), the change is of order of 0.01W/century. By contrast, injecting GHG into the atmosphere at the current rate is producing a forcing of order 4W/century over the entire globe.
I am always suspicious of statement like "The climate system is a very compelex system that nobody fully understands. " You will be hard pressed to find a scientist that would claim to "fully understand" any physical system. We do however understand a great deal about physical systems including climate. For instance, we can say with enormous confidence that if you change the incoming energy reaching the surface than the climate will change in response and furthermore, the amount of change will be positively (not necessarily linearly) related to the amount of change in that incoming energy. Scientists are a skeptical bunch butthey are extremely wedded to concept of conservation of energy.
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TVC15 at 06:02 AM on 4 June 2019Climate's changed before
MA Rodgers @ 717
Thank you once again for educating me so I can educate others!
With respect to the state of this planet and human activity I now see that's it too late to undo what human activity is doing to our climate.
I apologize if I come across as a "Debbie downer" but from all that I've learned thus far...it appears that this earth cannot overcome human caused destruction until we destroy ourselves.
I am not saying we should simply stop trying but when I look around the globe it's pretty evident that what we've unleashed on this earth is not stoppable even if fossil fuel use ceased 100% today.
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MA Rodger at 18:54 PM on 3 June 2019Climate's changed before
TVC15 @715,
The claim that "in every Inter-Glacial Period going back 800,000 years the sea level rose 3 meters to as much as 14 meters" is garbled nonsense, as is the comment about MIS-7 & MIS-9. The 'rise' presumably refers to SLR exceeding today's levels and the "3 meters" is probably referring to MIS-5 (although it is usually given as a little higher) which was the last interglacial 100,000 years ago while the "14 meters" is probably referring to MIS-11 400,000 years ago. (MIS-7 & MIS-9 were the interglacials inbetween these two.)
Reconstructing a SLR record over recent ice-ages is not as simple as the equivalent CO2 & polar temperature record. So it is not impossible that wildy contrardictory evidence exists and I'm not aware that a definitive source for ice-age SLR actually exists yet. Our good friend Google provides the graphic below although it requires signing-up to get a proper sight of the data it is based upon.
As for CO2 being below 300ppm during those previous interglacials, it was the planet's orbital configuration that allowed that extra ice-melt back then, the whole amplified by reduced albedo due to lower ice cover. Today those orbital configurations do not exist so without mankind's GHGs the planet would now be slipping into an ice-age and sea level would have been dropping. Our extra GHGs is more than preventing that and CO2 levels of 470ppm (not sure why that particular value is stated) will melt out Greenland (as happened in MIS-5) and a fair bit of Antarctica as well. So 14m SLR would be on the cards, although the melting is expected to take some millennia if you managed to stop at 470ppm.
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Ari Jokimäki at 15:08 PM on 3 June 2019New research, May 13-19, 2019
Thank you all! :-)
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TVC15 at 06:25 AM on 3 June 2019Climate's changed before
I meant to state that I think he's cherry picking and misrepresenting.
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TVC15 at 06:24 AM on 3 June 2019Climate's changed before
I've come across another climate change denier who stated these things.
If you read the peer-reviewed scientific articles, you will see that in every Inter-Glacial Period going back 800,000 years the sea level rose 3 meters to as much as 14 meters.
Sea levels during MIS-7 and MIS-9 were 10 meters to 14 meters higher than present.
What did you just say?
You said CO2 levels haven't exceed 300 ppm CO2 in 1 Million years.
So, what exactly is the point?
Who was burning fossil fuels in any of the previous Inter-Glacial Periods?
No one, yet sea levels still rose 3 meters to 14 meters.
In fact, CO2 levels ranged from 260 ppm to 280 ppm CO2.
So, the reality is that it doesn't matter if your CO2 level is 270 ppm or 470 ppm, because your sea level is going to increase 3 meters to 14 meters and neither you, nor anyone living, dead or who will ever live can stop it.
Once you accept that scientific reality, the best thing to do is let the Free Market handle it, instead of ramming useless laws down people's throats that will do nothing except screw people over.
I this he's cherry picking and misrepresenting.My questions are:
- Is it an accurate claim that in every Inter-Glacial Period going back 800,000 years the sea level rose 3 meters to as much as 14 meters?
- Is it accurate to state that it doesn't matter if your CO2 level is 270 ppm or 470 ppm, because your sea level is going to increase 3 meters to 14 meters and neither you, nor anyone living, dead or who will ever live can stop it?
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Ddahl44 at 04:06 AM on 3 June 2019The human fingerprint in the daily cycle
MA - thanks for the graphs. Lord(!) Kelvin temperatures I haven’t seen in years. We, in medicine, have trouble with converting C and F back and forth. It looks by the graph that the huge temperature swings on the moon are not so much due to the long lunar nights, but rather the long lunar days. Once it gets dark the temperature drops by 30-35 degrees C over 14 earth days. To extrapolate then, during a 12 hour earth night the temperature drops a little over 1 degree C. Not much. However from dawn to midday over 7 earth days the temperature rises an incredible 300 degrees. Extrapolation is more difficult for day changes since we’re on a curve and at least in Kansas, temperatures peak later in the day. But 6 hours of Earth day heating would increase the moon temperature by about 11 degrees. This is still more of a temperature change than Singapore, but to be fair to the moon, actually less of a change than a more comparable arid Earth locales, like say Phoenix, Cairo or Baghdad. They each had day/night differences yesterday of between 25 and 30 degrees F.
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wilddouglascounty at 23:40 PM on 2 June 2019New research, May 13-19, 2019
I hereby nominate Ari for the yet-to-be-created Un-Skeptical Accolades Award for his tireless contributions to this most valuable website. May you spend your newfound free time well; it is so deserved, and here's to John Cook and crew a note of encouragement to establish an Ari Jokimaki Internship position for someone to to fill Ari's very large shoes! I suspect there might be folks out there willing to contribute to such an internship position if given the opportunity to donate....
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nigelj at 08:14 AM on 2 June 20192019 SkS Weekly Climate Change & Global Warming News Roundup #22
"Climate crisis more politically polarizing than abortion for US voters, study finds"
So frustrating. Although Republicans rate the climate issue as very low priority compared to democrats, the article shows quite a number of Republicans want something done about it seemingly in contradiction, so perhaps the low priority ranking is just going along with the "approved tribal position" and their position on mitigation a better indicator of their real views. Although their real views are still rather lukewarm.
The cooperation on a carbon tax is still a long way away from achieving anything. Some say dont be judgemental of the other side in politics, work with them, be nice...but this does not seem to be yielding results when its tried. The grim reality is that on the climate, abortion, and guns issue both sides cannot be right.
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MA Rodger at 08:13 AM on 2 June 2019Humans and volcanoes caused nearly all of global heating in past 140 years
higgijh @5,
Adding a few numbers to the comment of Eclectic @6, the Vostok temperature data (for instance here) gives samples at least every 100 years back to beyond the last interglacial (the Eemian) and even back two more interglacials is still providing samples at least every 300 years. This data allows us to see that the current interglacial is uniquely long. The three previous interglacials peaked in hundreds of years while the present interglacial has lasted 10,000 years.
I would also add a few other comments:-
(A) A lack of glaciation over the Great Lakes is not a very useful marker for the climate change of the last century or so.
(D) The Milankovitch cycles ar not what "drives" ice ages, they are what 'triggers' ice ages. The 'drivers' are albedo (sunlight reflected away due to increased/decreased snow cover) and greenhouse gas concentrations. Mankind's GHG emissions have put pay to the ice-age cycle cooling & growing glaciation of the high northern latitudes so the coming ice age ain't gonna happen.
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Jonas at 07:28 AM on 2 June 2019New research, May 13-19, 2019
I already stated my appreciation of your work some time ago and can only repeat it: deep bowing .. I was asking myself how you managed to read/gather so much complicated stuff ..
If you have hints for other filtered climate sources for lay persons like me ..
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nigelj at 07:50 AM on 1 June 2019Humans and volcanoes caused nearly all of global heating in past 140 years
Higgij
I'm not sure what you are really getting at. I agree with eclectic. However I will throw in a couple of comments:
You expressed a concern that the early IPCC modelling did not predict the "pause" after 1998 (if I interpret you correctly). Scientists have always been up front that modelling cannot accurately predict relatively short periods like 10 years because they are influenced by natural variation. Eg clearly no modelling can predict volcanic eruptions or accurately predict a semi regular cycle like el nino, however modelling can predict longter term trends. In fact the pause does easily fit within error bars of the models see here.
"(F) The earth is just now coming out of a peak in the temperature variations caused by the orbital cycels. "
Not really refer here. Earth has been in a cooling phase for about 5,000 years and this has only been seriously interrupted by the warming spike since 1900.
"(G) When proxy temperature information inherently averages over 1000 years, the indicated peak temperatures over a 100 year period are drastically smoothed and diminished."
There is not enough data to get every short term temperature spike in the paleo record, however I recall reading somewhere that they use a random data gathering process which means its likely any large spike of 100 years would be captured. But even if past temperature record has short periods of rapid warming of 100 years comparable to recent decades since 1900, it would have to have an explanation, possibly intense volcanic activity. Volcanic activity was often very intense and protracted in Earths early history.
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Eclectic at 07:24 AM on 1 June 2019Humans and volcanoes caused nearly all of global heating in past 140 years
Higgijh @post5 ,
If I have correctly understood your thoughts : your are basically concerned by the low time-resolution of past temperature (proxy) records & what may be inferred from them.
Certainly, the time-resolution becomes fuzzier, the farther back in time we explore. We can delineate the past 1000 - 2000 years of climate changes rather more exactly than the past 10,000 years or the 800,000 years (of the ice-core records) or the past 500 million years (with very low time-resolution in say the Ordovician period).
Yet the laws of physics haven't changed during all that time, and we can see [for example] that Newtonian Laws of Motion must have applied just as well during the Ordovician as during the current Holocene.
How does that apply to world temperature changes? If we look at the past 10,000 years (of the Holocene interglacial) we see a flat plateau of about 5,000 years [the "Optimum"] followed by the latest 5.000 years showing a gradual decline in temperature, which would eventually have triggered a new glaciation in about 20,000 or 30,000 years' time or more (an "abnormally" long interglacial, owing to the current low-ellipticity of Earth orbit). Or at least, that is what would happen, without the human [CO2] intervention of the past century or two.
The temperature record of recent centuries shows that the reaction to a major volcanic eruption is a very brief world temperature dip (less than 5 years). And the reaction to a major diminution of insolation (a Grand Solar Minimum) is a much more prolonged dip ~ but only about 0.3 degrees. These sorts of excursions explain why the "shape" of the Holocene resembles a relatively smooth plateau. The "wiggles" of temperature (such as the Medieval Warm Period or the Little Ice Age) are very minor indeed, against the general background.
Higgijh ~ going farther back in time, if you had been alive during the time of the Younger Dryas (and miraculously you lived for twice Methuselah's age! ) you would have seen a large excursion of world temperature during a 1000 years. But that change was gradual, compared with the rocket-like rise in temperature of the immediate 50 - 100 years past. And the cause of the Younger Dryas would have been very obvious to you (to you and your team of observer-scientists). The point being, that "low time-resolution" is not a problem in seeing the results of major climate factors.
Similarly, going back through 800,000 years, you see the climate alter in a cyclic way (Milankovitch insolation "forcing changes" of up to 0.7 watts/m2 , triggering a CO2 greenhouse change much larger than that). Again, the "smoothing" of the time-resolution record is not a problem for understanding the history.
For a separate additional effect to produce a rapid spike (up or down), there would have to be some large & powerful short-term causation for temperature change. Just as in Newtonian terms, a mass does not change velocity unless it is acted upon by a force ~ so too for climate : climate does not change unless something causes it to change.
Which is why - in the observed absence of major climate factor changes - it does not matter that the (proxy) climate record has a resolution far worse i.e. far fuzzier than annual / decadal / or centennial, as the case may be.
Higgijh, I hope I have addressed your basic concern. But perhaps you have deeper unexpressed concerns?
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higgijh at 01:55 AM on 1 June 2019Humans and volcanoes caused nearly all of global heating in past 140 years
I appreciate the response I've gotten on my comment.
Note that although I reference page 43 twice, one reference is from the Synthestis report and the other is from the Summary report.
My current viewpoint. (A) Climate change is real. Anyone who says differently has to account for the absernce of the glaciers over the Great Lakes. (B) Carbon Dioxide is a green house gas and humans are pumping a lot of it into the atmosphere. So humans must be contributing to warming. (C) The climate system is a very compelex system that nobody fully understands. (D) Major changes in climate temperature that have brought on past ice ages is primarily driven by earth orbital cycles with periods of 23,000 years, 42,000 years, and 100,000 years. (E) Climate temperature proxys over the last million years indicate that peak temperature peaks are often (not always) very sharp (with respect to a 1000 year grid). (F) The earth is just now coming out of a peak in the temperature variations caused by the orbital cycels. (G) When proxy temperature information inherently averages over 1000 years, the indicated peak temperatures over a 100 year period are drastically smoothed and diminished.
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Eclectic at 20:41 PM on 31 May 2019Humans and volcanoes caused nearly all of global heating in past 140 years
Higgijh @post3 ,
(3) My apologies for fumbling your IPPC reference, but I turn up a completely inappropriate graph at Page 43. Would you be kind enough to insert your correct graph into the thread here? [Remembering the 500px width limit.] On second thoughts, it would be better for you to select a different thread ~ one where the question of Asian coal vs gas usage is on-topic (as it is not really relevant to the headline topic here of Humans and Volcanoes causing global heating since 1880 ).
(2) There is always the question of localization effects and time-resolution effects, in the assessing of temperature proxies in ice and sediments. But broadly speaking, these proxies are useful even when time-resolution is low.
We know that the climate only changes when something causes it to change ~ so in the absence of major factor changes in the last 10,000 years, we can [for example] be confident that the present-day world temperature is distinctly hotter than the Medieval Warm Period or the Roman Warm period or the "Holocene Optimum".
(1) Higgijh, this IPCC Page 43 seems the correct one you mean for (1). But I am entirely unclear on what difficulties you are having with it.
Climate trends are best assessed over a period of usually 30 years (or more) ~ so it is rather unsurprising that the Figure (c) over 60 years shows a good concordance between observations & models. Likewise it is not surprising that the short periods Fig. (a) 1998-2012 and Fig. (b) 1984-1998 , show observation/model disparity, since "natural internal variability" is more dominant during such very short periods.
The construction of climate models serves two purposes :-
# helping the assessment of individual climate factors [e.g. evapo-transpiration]
# projecting what may happen in the future, by a way which is likely to be much better than a guess ( = the equivalent of holding up a wetted finger to the breeze ).
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RedBaron at 19:28 PM on 31 May 2019New rebuttal to the myth 'Holistic Management can reverse Climate Change'
@scaddenp,
Unfortunately I am still waiting for the published results of the study on gas exchange they were doing in Idaho where they found the increase in soil water infiltration and content on semiarid HM simulated land. I don't know if they are still collecting data or what? All I know is that during a USDA-NRCS seminar for farmers, it was mentioned by a NRCS scientist that they were attempting a new protocol suitable for full scale in situ direct measurments to finally lay to rest the doubters.
Keep in mind though, I already gave you this:
Climate change reduces the net sink of CH4 and N2O in a
semiarid grasslandReducing a net sink is still a net sink, just smaller. That means in no way does increasing the area of land in grassland, particularly the land restored to productivity after being degraded by poor management in the past, cause an increase in greenhouse gasses. Quite the contrary, grasslands are one of the few biological sinks for both NO2 and CH4, and the soil sink under a grassland the largest terrestrial CO2 sink.
It's between good, better, best whenever we improve or restore the ecosystem function of any grasslands by any means. In no way does any of these minutia in any way refute Savory's Holistic Management. It's still taking land that is a net source or if completely degraded, net zero; and turning it into a rather large net sink for carbon and restoring the hydrological cycles as well as quite a few other benefits not least of which is food and income for people.
"That would imply very low productivity per hectare."
Counterintuitively, no. In fact both primary productivity of the grassland and yields of meat, milk and/or wool all increase to such a large degree that even more wildlife are seen too!
This is because grass growth is not linear. It follows a sigmoid curve. So the trick is to time the grazing in such a way as to optimize grass growth rather than stocking rate. With more grass and forbs comes more yields, but that is almost an after thought. The focus is in how to restore the whole ecosystem in the context and framework of the land manager's long term goals for restoring the land for future generations. This is where the term "Holistic" comes from in this context. Most people who use the system stop thinking of themselves as ranchers or dairymen, but rather as grass farmers. They work at growing the best grassland ecosystem and use the animals to support that goal. It's a whole new paradigm and POV... but low and behold a fully functional grassland ecosystem is so much more productive that in the end it brings more yields and profits from the meat, milk, and fiber too.
For some technical information on how this is done, here is an ag extension guide with useful information:
There are some really interesting things found in there, like although the dairy produce slightly less milk per cow than the highly supplemented feeds given confined dairy, the number of cows that can be supported per acre increases so that based on land use, yields increase. More cows producing slightly less milk per cow, but total yields, quality of product and profits increase. It also shows how to plot growth curves of specific types of grass to determine the best time to bring the cows in for a day or two. (just after the highest growth rate for each dominant species)
How this improved ecosystem primary productivity can be harnessed for wildlife increases can be found here:
Grassland Birds: Fostering Habitats Using Rotational Grazing
I know that's just a side issue to the AGW debate, but it is key information in Holistic Management, which always views and considers the whole rather than just isolated parts.
"Permaculture is a philosophy of working with, rather than against nature; of protracted & thoughtful observation rather than protracted & thoughtless labor; & of looking at plants & animals in all their functions, rather than treating any area as a single-product system." Bill Mollison
And yes, in case you were wondering, HM is a form of permaculture.
Can you give a paragraph on the difference between HM and MIRG?
As a general rule MIRG (Managed Intensive Rotational Grazing) is any number of closely related grazing systems that came out of the work of Andre Voisin's Rational Grazing. And yes Savory was highly influenced by that work too. So yes HPG is a form of MIRG.What Savory did was spend decades working out how to take Voisen's work to the next level where it could be used on areas that defied rational management in the past. So basically what Savory did was take Voisen's breakthrough and work out how to make it universal under a much wider range of climatic, soil, social, technological, and cultural conditions. He basically dramatically reduced the naysayer's, "Great but that wont work here" down to basically near zero (within reason).
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higgijh at 12:07 PM on 31 May 2019Humans and volcanoes caused nearly all of global heating in past 140 years
This is a good article and I appreciate the information. However, I still have a problem with the IPCC 2014 report. (1) On page 43 of the Synthesis report there is a graph showing the predicted degrees C change in temperature per decade of climate models for 1998-2012. All of the models are predicting temperatures that are too high for that time frame excepth possibly one. Most of them get the number many times too high - like factors of 3 to 8 all the way up to 10. I don't have any problem with constructing a model of past climate and including effects as they are better understood. I do have a seious problem with using such models to extrapolate far into the future. This is particularly true when the extrapolated models are so far off at the point where they go from modeling the past to predicting the future. (2) Another question I have that is a problem for me is: "What is a climate temperature number?" Core samples, whether ice cores or sediment cores, generally give proxy temperature numbers that are averages over many years - sometimes one or two thousand years. So is a climate temperature an number measured today somewhere in the middle of the Pacific ocean? Or maybe an average over a year. Or averages of global temperature measurements over a year or a decade or a century, ... , or maybe a millenium? (3) Finally, there is another interesting graph in the 2014 IPCC report on page 43 of the summary report. This graph shows that the OECD-1990 Countries have held their emissions nearly constant as a group since about 1970. That same graph shows that Asia has been increasing their emissions by about 12 Gt/Yr over the same period. I think that this points to a serious problem over which we have very little control. A switch by Asia from coal to natural gas would probably hit the emissions problem where a punch would do the most short term benefit.
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scaddenp at 09:35 AM on 31 May 20192015 SkS Weekly Digest #38
I dont know about "quietly". Problems with coal estimates from a grossly inefficient bureaucracy were uncovered by IEA in 2013 and they have steadily working on fixes since then. Big revision in 2015.
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litvichar at 09:25 AM on 31 May 20192015 SkS Weekly Digest #38
In May, China's statistical agency quietly raised estimates of how much coal the nation has burned since 2000.
SOurce: https://laffaz.com
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scaddenp at 07:43 AM on 31 May 2019New rebuttal to the myth 'Holistic Management can reverse Climate Change'
Do you have a reference for full gas fluxes under a property you consider to be HM with high rates of C sequestration? I was also noting that high rates of C sequestration go with N input both from observational evidence and biological fundimentals. For any farm, you still have a stocking rate of total animal-days/total land. However, I agree that continuous versus rotational grazing is going to be important and it is hard to find that in the Conant paper. The Mandan and Cheyenne data which are best for length of time and gas flux are both continuous seasonal grazing.
If most land has no animals for most of year, then that is very low stocking rate in my opinion.That would imply very low productivity per hectare. Yet (quite a while ago), you were saying that dairy productivity (milk solid per hectare) in your systems were on a comparable rate to NZ rotationally-grazed pastures?
Can give a paragraph on difference between HM and MIRG? I find it frustrating in papers (eg Briske Teague controversies) where lack of good definitions muddy the waters.
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nigelj at 07:08 AM on 31 May 2019Humans and volcanoes caused nearly all of global heating in past 140 years
Agree with BB. While the article is great and the headline is technically correct it gives a bad message that volcanos are a big factor in long term warming, and it will delight climate denialists. We know people often only read headlines.
It might have been better to word it differently like "new study better explains early 20th century and recent arctic warming"
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