CPEP Seminar: Missing Ice and Altered Ecosystems: Climate Lessons from a Warmer Greenland
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- Опубліковано 25 кві 2024
- Speaker: Yarrow Axford, William Deering Professor in Geological Sciences, Northwestern University
Geologic records of past warm periods reveal how the Earth system responds to warming climate, and thus provide clues about how future warming may unfold. Quaternary scientists have long shown that Greenland and many parts of the Arctic experienced temperatures warmer than present in the early to middle Holocene due to elevated summer insolation - providing a useful natural experiment.
This talk will overview several veins of our recent research using lake sediments to investigate climate and environmental change across Greenland during the Holocene “thermal maximum.” How warm did Greenland get, and importantly, what were the consequences of warming for glaciers and ecosystems?
![ОРБАН приехал к ПУТИНУ и "отчитался" о поездке в Киев 😁 [Пародия]](http://i.ytimg.com/vi/_0ukDovOWq8/mqdefault.jpg)
Recent Arctic melting is actually due to Chinese industrial dust, reducing the ice-sheet albedo.
See paper: Modulation of Ice Ages via Dust and Albedo.
See also the darkening ice observed by the Dark Snow Project.
There has been a lot of dust deposition over recent decades.
Recent warming has little to do with CO2.
R
Thank you for a great talk! The claim that I keep hearing repeated over and over is that it's currently hotter than it's been in the past 100k years, but you very clearly show evidence of the Arctic being 3-4C warmer just 10k years ago. Would you consider today's warming/melting to be alarming when just 5-6k years ago, most of the sampled glaciers were either smaller or non-existent compared to today?
It is important to note that the reasons for the Arctic being hotter are different. In the early Holocene it was because of oscillations in the Earth's orbit causing there to be more total sunlight to the Arctic specifically during summer. Now it is due to the changes in atmospheric composition causing a global increase in total thermal energy. The work indicated here indicates what will happen to the Arctic as it warms, but not the rest of the world.
@@personzorz For sure, but it seems like a good portion of the alarm is coming from the idea of Greenland melting and dumping tons of freshwater into the ocean, causing catastrophic sea level rise and potentially tipping the AMOC into turning off. But this study contradicts that alarmist point of view - we know that sea level rise has been relatively stable for the past 5k years, even with a melting arctic.
@@307alexk I think you'd need to ask the presenter about the altitude of the ice sheet surface. The higher temperature readings were coming from ground level lakes, while a lot of the melting would be coming from the surface of the ice sheet which used to be higher. I naively would think that that would make modern temperatures like the early Holocene lead to more melt, but it's not my work.
The global average is what is referred to by hottest for 100k years. This Greenland warming is a regional effect, but very relevant since it is currently warming much faster than the current global mean, once again.
Please provide a link to your information. I believe, without checking, you are lying or stupid.
The mid 20th century was very cool. So it’s no surprise Arctic temperatures are similar to the early 20th century now. You need to look at the early 20th century to understand the warming now.
This is very interesting. It was like when I learned that the bubbles in streams were formed by humic acid and that I couldn't get acorns to sprout without it.
The idea that it’s not warm enough to cause the ice melt is kinda missing the point. It’s a debate against precision versus accuracy. Obviously it’s warm enough to heat the ocean somewhere to bring this warm water to melt this ice. Being precise about the local air not being warm enough is inconsequential and beating a dead horse. How does this information change the outcome?
So this theory confirms that an increase in atmospheric CO2 causes the melting that we observe …?
Totally missing the point.
Ice sheets are geothermal heat traps, and pressure caps that pump water at up to 6000psi above sea-level pressure down into the litho sphere, where it is solvated as ionic fluids in the mantle. Storing 57 mega joules per kg of that trapped geothermal heat as hydroxyl and protons in low temperature melts. Albite as one example, fully miscible with hydrous fluids from 10 to 20 km down, and above 600 degrees.
When the geothermal borecap starts to rupture ate the fringes, in the fracture rifts of ice streams, the pressure drop releases that thousands of years of stored chemical energy as thermal energy, and an exponential runaway melt, blowup of the ice dome commences.
That's why hot water is blowing out from under all the major ice streams of Greenland and Antarctica.
This also initiates a pulse of spreading ridge volcanism, like you are seeing in Iceland, and subduction, as the sudden isostatic uplift occurs at the continental ice sheet fringes.
Warmer sea and Air temperatures cause polar ice sheets to grow, not collapse. 🙄
@@Maungateitei wow. That is interesting. A lot to 🤔
@@JohanThiart Relativity is also, as you say, a "theory"
There's in fact 2 theories of relativity, special and general. If those 2 "theories" weren't taken into account, GPS would no work.
That's like the difference between a kitchen table and a multiplication table. Not all tables are equal.
In 2014, the maximum Arctic Sea ice extent reached a coverage area of approximately 5.02 million square kilometers.
In 2024, the maximum Arctic Sea ice extent occurred on March 14, with an estimated extent of approximately 15.01 million square kilometers.
Where did you get this information? According to ChatGPT the number of square kilometers decreased between 2014 and 2023 but I don't know where ChatGPT gets this information from.
Extent is meaningless, as a trend, without volume.
The Danish cover what’s going on with ice on Greenland and have done good science for decades. Polar portal
@@remcovisser7927 You just answer your own question all AI (?) generated responses are pre programed with dogma wokeism climatic chang crisis catastrophism propaganda. let me give you a short analysis study and logic calculations and FACTS: First please notice that all asertions by the IPCC, models and rhetoric from the "consensus" avoid or disregard even mentioning: SOILS RESPIRATION it is for this reason ALL models are a fraud....they produce 40 to a 100 models fixing the outcome! Is this stupid or what there fore they do NOT include the larger forcings. Other very important FACT is natural vs Oil Carbon isotopes are different in quantity and warm thermal radiation potency. Guess what isotopes proportion exist in the atmosphere? ~99.89% are produced by natural earths processes and only ~1.21% by petroleum ..these and many other fraudulent notions are the basis for AI generated information ..no matter what you ask in ANY GLOBAL platform Google, Edge, the net is ifested and controlled by the Globalists...don t believe what I say check it out, and compare !
@@christinearmington Correct! thats why they the "consensus" always use "extent"!
You need to listen to Tom Gallagher’s paleoclimate lectures (3 of them)
Do climate models take into consideration soot from Canadian forest fires that darken Greenland ice sheet, dirty ice absorbs more sunlight causing faster melting?
That’s a good question. Models are so stinking complex that I’d be very surprised if they didn’t account for that. Maybe they’re able to estimate the albedo by looking at satellite imagery.
Not last time I checked. Ice melt models are still in their infancy. There's a lot of work to be done in that area.
I'm trying to think of a glaciologist that would know... perhaps Jason Box. I know he did lots of observations/measurements on dark now on Greenland and once heard him critic models on that topic.
She mentioned that she would discuss fires in the beginning. I didn’t hear anything in that regard unless I missed it. What you are talking about is a real and intense phenomenon which caused the recent floods in Pakistan via ash from a fire melting Himalayan glaciers and submerging a third of the country underwater.
I did not hear of that event, I will look it up,@@WarAndFame
Look up "Dark Snow Project" and Glaciologist Jason Box. He works in Greenland and puts up monitoring and weather stations on Greenland.
He has a youtube channel and has quite a few papers about Greenland melt and weather triggering it.
@@WarAndFame I just checked. The ash was a contributing factor in that event.
'University of Michigan-Dearborn Professor Ulrich Kamp about how glacial melt caused by climate change and changing monsoon patterns have caused flooding in Pakistan"
I am grateful for your research. Where was the plate Greenland is on in the holoscene? I seem to remember a time when Norwegian settlers lived in Greenland. They even named it GREENland. The weather changed, and all starved to death when cold took over. Norwegians named Iceland to keep settlers away. I am NOT convinced man can do a thing to change the climate. It's bigger than anything piddly man can do.
the natural CO2 emission rate is 12 gigatons per 200 years. Industrialization is now 100 times faster CO2 emission rate than the natural one.
@@voidisyinyangvoidisyinyang885 Huge #, Sounds SCARY! How does "12 Gigatons" compare w/ other parts of the CO2 system?? More importantly: What EMPIRICAL (observational) evidence -- NOT embellished by opinion, value JUDGEMENT(s), and/or CONJECTURES - is there, that such large increase in atmospheric CO2 concentration is LIKELY* to CAUSE higher (average) temps, let alone that such higher (AVERAGE) temps will be necessarily harmful to humanity OR earth's ecosystems??? *("likely", because we cannot know for SURE that such increased atmospheric CO2 concentration WILL raise AVERAGE temps, by ANY notable amount, let alone whatever amount the various misanthropically-biased MODELS CLAIM will - or even MIGHT - occur!)
It’s OK if you’re not convinced. Lessons, keep repeating themselves until learned. You need to understand that CO2 is a greenhouse gas, understand the significance of the keeling curve(you can look that up) how ice extent affects the reflectance of the suns energy(albedo), that 90% of the energy that makes it to earth is absorbed by the oceans. After you have that nailed read.” storms of my grandchildren.” by James Hansen. It’s from 2008, but the science is the same.
Climate science is pretty important to the near term Survival of our democracy. If you don’t understand it, you probably shouldn’t vote because you won’t know who is lying to you.
All the best to you,
Joseph Fourier first figured out global warming two hundred years ago!! How long will it take for people to overcome all the Big Oil willful ignorance propaganda? hahahaha.
wuducallme? whos piddly/
SuperDuper Interesting
PERIODIC TABLE OF THE ELEMENTS:
Potential completion of the Periodic Table of the Elements:
I currently believe that there are 120 chemical elements in this universe. If a person were to look at how electrons fill up the shells in atoms: 2, 8, 18, 32, 32, 18, 8 (seven shells), and realizing that energy could freely flow in this universe if nothing stopped it from doing so, then a natural bell shaped curve might occur. An eighth energy shell might exist with a maximum of two elements in it, chemical element #119 (8s1) and chemical element #120 (8s2).
Chemical Element #119 (8s1):
#119 I put at the bottom of the Hydrogen group on the Periodic Table of the Elements. It only has one electron in it's outer shell with room for only one more electron. Energy might even enter the atom through the missing electron spot and then at least some of the energy might get trapped inside of the atom under the atom's outer shell.
Chemical Element #120 (8s2):
#120 I put at the bottom of the Helium group since it's outer shell is full of electrons. It might have some of the properties of group two, Beryllium group (Alkali Earth Metals group) since it has two electrons in it's outer shell; as well as some of the properties of the Helium group (Noble Gases group) since it's outer shell is full of electrons; and if you look at the step down deflection of the semi-metals and where #120 would be located on the chart, it's possible #120 might even have some semi-metal characteristics. #120 would be the heaviest element in this universe. I believe chemical element #120 could possibly be found inside the center of stars.
When a neutron split inside of this atom, it would give off one proton, one electron, neutrinos and energy. The proton and electron would be ejected outside of the atom since all their respective areas are full. One proton and one electron are basic hydrogen, of which the Sun is primarily made up of, and the Sun certainly gives off neutrinos and energy. And note, it's the neutron that split, not a proton. So even after the split, there are still 120 protons inside of the atom and the atom still exists as element #120. The star would last longer that way.
In addition, if the neutron that split triggered a chain reaction inside of the star, this could possibly be how stars nova, (even if only periodically).
If stars were looked at as if this theoretical idea were true, and found to even be somewhat true, then we might just have a better model of the universe to work with, even if it's not totally 100% true. And if it's all 100% true, then all the better. (Except of course for those who might be in the way of a periodic nova or supernova. They might have a no good, very bad, horrible day.)
Go back to school
@@personzorz And yet, how the electrons fill up the shells in atoms would suggest an 8th energy shell existing with a maximum of 2 elements in it. Maybe if you were smart enough you would be able to discern that too?
@@personzorz Plus: You: Joined Jul 24, 2007; 1 Video; 6 Subscribers; Nothing in your 'About' section; Hiding behind a sock puppet ID. Maybe if you want people to take you more seriously you would not troll so much?
I got a D on my chemistry nomenclature 😄 but I never give up!!
@@sumiland6445 Never stop learning. Be an honest, sincere truth seeker and knowledge, understanding and wisdom will come that you could apply.
You know what I'm going to ask ... 😄 Any new data on Vertical Atmospheric River Rapids in Greenland? They're the kind of new weather phenomenon that will be truly terrifying
You really need to compare current conditions to the early 20th century not the mid 20th century because the mid 20th century was the coldest in the 100 year period. The early 20th century was similar in temperature to current times.
Bonjour
If you look up Summit Camp, Greenland, on wiki they falsely claim the highest max temp was 2.2C on 13 July 2012 and on 28 July 2017.
But when you look at the hourly average temperature on those dates the temperatures did not go above freezing at 2m.
The highest recorded temperature for 2012 was on 11 July at 0.8C (the only day that got above freezing for 2012). In 2017 it never got above freezing.
Why the misinformation? You are supposedly EDUCATED.
Humans existed during Mammoths living year round in Alaska and what about our Star magnetic strength and the Earth's magnetic strength?
hydroplate theory baby
Increased input because of decreased magnetic field can warm the ice directly and instigate under ice volcanic eruptions and geothermal activities.
Save Our Planet Now!
How? Can't even stop Putin.
The planet is actually thriving thanks to the slight natural increase in CO2, we could actually do with more. Research greening of the earth.
Fed up with the climate B/S, watch this exposure by many eminent scientists of the corruption in science, academia and government. Climate-The Movie.
The planet is actually thriving thanks to the very slight natural rise in CO2, the gas of life. Research 'Greening of the Earth'.
ua-cam.com/video/p4vSMj4R5Rg/v-deo.html
BS
OMG could you imagine Greenland covered in insects, birds, plants forests and mammals. Oh the horror.
In isolation it doesn't sound bad. Like a half-truth. In context it's terrible for the rest of us.
The ice sheets in Greenland are the air conditioners for the northern hemisphere. Good luck without them.
@@lrvogt1257 How is it terrible for the "rest of us"? The greatest diversity of life on this planet resides in the tropics not Greenland.
@@mariondaniels2934 The great ice sheets have been disappearing for 20,000 years. Humans without an ounce of technology survived just fine. In fact, life has flourished throughout this time period to present day across the globe.
Science confirms that the majority of warming is occurring in the coldest most uninhabitable places, during winter, and at night. You couldn't ask for a better scenario.
Imagine the UK ruling the waves 10 feet under.
Or the Netherlands, a big bath tub, disappearing under the waves?
Both places will be filled fish, and plants and algae etc of course.
❤ planet Earth is suspended in Space where the temperature is minus 273 degrees Celsius. Earths biggest problem is staying warm and will remain in an Ice Age for the next million years
And in the next few hundred years we'll get much warmer very quickly before slowly cooling off over a hundred thousand years.
@@personzorz . The world is not warming . In fact it is getting colder as exemplified by the coldest , heaviest snow blizzards occuring in Feb & March 2024 in Mongolia & North China which froze to death 9 million livestock . And is why cattle prices hit an all time record high in Feb & March on the CME. Proof that the world is getting much much colder.
@@personzorz LOL. the planet is already cooling. Greenland Ice mass balance has increased from a low in 2012 of 20 GT to being consistently over 300GT and 400GT last year.
CO2 does not cause significant warming, compared to 1850 (The beginning of the Industrial Revolution) CO2 has only increased by 50'%, increasing the greenhouse effect by about 2W/m2 which the Stefan Boltzmann law tells us is less than 0.4degrees C of warming. For CO2 cause just 1 degree of warming compared to 1850 it would need to be 750ppm. and for another 'CO2driven' degree of warming would require a level of over 2000ppm.
If you need an explanation of the recent warming look to the sun not a trace atmospheric gas.
Hint; Big black spots on the sun and the planet cools a little, No Big black spots on the sun and the planet warms a bit (as happened during Maunder Minimum which warmed the planet out of the mini ice age (CO2 DID NOT CHANGE). The planet is following the Gleissberg Cycle, we have passed the recent minimum and we are on the way towards another cooling phase.
One of the BIG benefits of the rise in CO2 has been a vast increase in food production. 50 years ago we could not produce enough food for 4 billion people with 1 million famine deaths every year.now we are feeding 8 billion people with fewer than 25,000 famine deaths. Int the last 50 years 3rd world crop yields per hectare have doubled while first world yields have quadrupled thanks the fertilizers and better seed, weed and pest control not available to the 3rd world.
Co2 is feeding the world not warming it.
@@personzorz . You have been successfully indoctrinated .
We aren’t in an ice age. Thats the new global warming denial. It produces the feeling that the warming is somehow the normal state. We are in an interglacial period. How can you be in an interglacial period if we are in an ice age. In fact, the recent Holocene term is measured by the ending of the ice age.
I want to listen but this profs voice too unpleasant to listen to.