Climate Change Catchment Thread

[Desert Fox]

I'm not sure why people are responding to my post with things loss of arctic sea ice does cause.  I neither said nor implied that it had no effects; merely that it was worth pointing out that it does not have that particular effect.

Mea culpa

[Soldier of FORTRAN]

Update on Larsen C: Crack grows 6 miles, could calve in 12 miles.

[Desert Fox]

Cracking at the rate of half a kilometer per day

[lonely moa]

Cracks are becoming a problem.

http://www.bbc.co.uk/programmes/p04p5zl2

http://i.dailymail.co.uk/i/pix/2014/08/08/1407498221849_wps_4_British_researchers_livin.jpg

[Soldier of FORTRAN]

[Soldier of FORTRAN]

Warning: Loud due to wind



Thawing permafrost releases methane, creating a variety of effects ranging from craters to jacuzzi-like bubbling in lakes.  An uptick in such methane releases in Siberia has been in the news lately (video's from '16, but is from Siberia).

[taimaia]

I have a geologist friend that presented me with the argument that the problem with the man causes climate change hypothesis is that it only looks at a small period , and that most of the change today can be explained by something called milankovitch cycles and presented me this article http://www.paulmacrae.com/?p=62

Is there any response to this sort of argument  ??  If so where can  I find articles that talk about this matter ?  Most of the people against the idea of global warming have been cranks, but this friend is a serious geologist  not just random guy on the internet. Thanks in advance =)

[Mr. Beagle]

I have a geologist friend that presented me with the argument that the problem with the man causes climate change hypothesis is that it only looks at a small period , and that most of the change today can be explained by something called milankovitch cycles and presented me this article http://www.paulmacrae.com/?p=62

Is there any response to this sort of argument  ??  If so where can  I find articles that talk about this matter ?  Most of the people against the idea of global warming have been cranks, but this friend is a serious geologist  not just random guy on the internet. Thanks in advance =)

This claim caught my eye:

For example, in March 2008, a poll of Alberta’s 51,000 geologists...

Can any Canadians here verify that there are 51,000 geologists in Alberta? If we are talking vaguely about people in the fossil fuel industry, then we have a very biased dataset, and most are likely engineers rather than scientists (speaking as an almost engineer, having taken all of the basic courses). The mindset is VERY different, which is a key reason why I escaped.

[Soldier of FORTRAN]

tl;dr:  Ice-melt produces a cold, low salinity/density layer which rests atop the northbound warm, high salinity/density water from the Atlantic.  This cold layer provides significant insulation to sea-ice.  As sea ice retreats, this inversion retreats.  It's a positive-feedback loop which is occurring in a quarter of the deep Arctic and is responsible for at least half of sea ice decline in this quarter. 

Article: Climate change is literally turning the Arctic ocean inside out
From: Washington Post
Date: April 6, 2017

There’s something special — and very counterintuitive — about the Arctic Ocean.

Unlike in the Atlantic or Pacific, where the water gets colder as it gets deeper, the Arctic is upside-down. The water gets warmer as it gets deeper. The reason is that warm, salty Atlantic-originating water that flows into the Arctic from the south is more dense, and so it nestles beneath a colder, fresher surface layer that is often capped by floating sea ice. This state of “stratification” makes the Arctic Ocean unique, and it means that waters don’t simply grow colder as you travel farther north — they also become inverted.

But in a paper in Science released Thursday, a team of Arctic scientists say this fundamental trait is now changing across a major part of the Arctic, in conjunction with a changing climate.

“I first went to the Arctic in about 1969, and I’ve never seen anything like this,” said Eddy Carmack, a researcher with Fisheries and Oceans Canada and one of the study’s authors. “Back then we just assumed the Arctic is as it is and it will be that way forevermore. So what we’re seeing in the last decade or so is quite remarkable.”

In a large area that they term the eastern Eurasian basin — north of the Laptev and East Siberian seas, which in turn are north of Siberia — the researchers found that warm Atlantic water is increasingly pushing to the surface and melting floating sea ice. This mixing, they say, has not only contributed to thinner ice and more areas of open water that used to be ice covered, but it also is changing the state of Arctic waters in a process the study terms “Atlantification” — and these characteristics could soon spread across more of the Arctic ocean, changing it fundamentally.

The study was led by Igor Polyakov of the University of Alaska at Fairbanks, in collaboration with a team of 15 researchers from the United States, Canada, Russia, Poland, Germany and Norway.

...

Those changes are occurring across about a quarter of the deep Arctic Ocean (the part that lies out beyond the continental shelves that encircle it).

One key feature of the change is that a middle layer of the ocean in the Arctic dubbed the “halocline” — a cold layer below the fresher surface where the water’s saltiness increases rapidly — is thinning and weakening. The halocline had previously served as a cap, preventing mixing between the cold fresh surface waters and warmer, saltier Atlantic waters — in essence preserving the distinct layers in the ocean. But that cap is now growing thinner, the research suggests.

The result is that at least half of the sea ice decline in recent years in this region can be attributed to warm ocean waters climbing up from the depths, rather than to the warming atmosphere.

...

“This whole thing about the ocean’s role in sea ice retreat, it used to be minimal, but as sea ice retreats it’s one of those positive feedback mechanisms,” Carmack said. “And we’re talking a lot of heat in the Atlantic layer, it could melt all the ice in the Arctic if it were to pop up to the surface.”

[Soldier of FORTRAN]

Article: Japan’s cherry blossoms are emerging increasingly early
From: The Economist
Date: April 7, 2017

...

[...] Diarists have keenly chronicled the comings and goings of cherry blossoms for centuries—records from Kyoto, the old capital, date back 1,200 years. This precious, ancient data set reveals a disturbing trend: in recent decades, the blossoms have emerged much sooner than they once did.

From its most recent peak in 1829, when full bloom could be expected to come on April 18th, the typical full-flowering date has drifted earlier and earlier. Since 1970, it has usually landed on April 7th. The cause is little mystery. In deciding when to show their shoots, cherry trees rely on temperatures in February and March. Yasuyuki Aono and Keiko Kazui, two Japanese scientists, have demonstrated that the full-blossom date for Kyoto’s cherry trees can predict March temperatures to within 0.1°C. A warmer planet makes for warmer Marches. The usual full-blooming date in Washington, DC, whose cherry-blossom festival is a relative newcomer (it launched in 1927), has also moved up by five days since the first recorded date in 1921.

...

[diessoli]

I have a geologist friend that presented me with the argument that the problem with the man causes climate change hypothesis is that it only looks at a small period , and that most of the change today can be explained by something called milankovitch cycles and presented me this article http://www.paulmacrae.com/?p=62

Is there any response to this sort of argument  ??  If so where can  I find articles that talk about this matter ?  Most of the people against the idea of global warming have been cranks, but this friend is a serious geologist  not just random guy on the internet. Thanks in advance =)

Why did I look at this article? It's just so depressing to see people (like the journalist author) swallow these old zombie arguments without regard for the nuances of actual research and even basic logic. Depressing.

However if you just want to respond to the Milankovitch cycle argument, the short version is: yes these are known to drive long term changes in the climate but their effect is too small to explain the recent temperature increases (their 'forcing' is too small).

Contrary to what Mr. Mac Rae writes, climate scientist do take the long view and look at the geologic record (there is a whole field called Paleo-Climatology).

https://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6.html

[geekoid]

I have a geologist friend that presented me with the argument that the problem with the man causes climate change hypothesis is that it only looks at a small period , and that most of the change today can be explained by something called milankovitch cycles and presented me this article http://www.paulmacrae.com/?p=62

Is there any response to this sort of argument  ??  If so where can  I find articles that talk about this matter ?  Most of the people against the idea of global warming have been cranks, but this friend is a serious geologist  not just random guy on the internet. Thanks in advance =)

I would remind him that he is NOT a climatologist.

Then talk about the science of global warming itself. Because of he can't created tests that refute the basic science, then he has to accept climate change if he actually think scientifically.
Please feel free to run this by an actual practicing climatologist.
Something like:

anthropomorphic global warming (AGW) is a fact.

1) Visible light strikes the earth Testable? Yes. Tested? Yes. Could anyone devise a test? Yes

2) Visible light has nothing for CO2 to absorb, so it pass right on through. Testable? Yes. Tested? Yes. Could anyone devise a test? Yes

3) When visible light strike an object, IR is generated. Testable? Yes. Tested? Yes. Could anyone devise a test? Yes

4) Green house gasses, such as CO2, absorb energy(heat) from IR. Testable? Yes. Tested? Yes. Could anyone devise a test? Yes

5) Humans produce more CO2(and other green house gasses) then can be absorbed through the cycle. Testable? Yes. Tested? Yes. Could anyone devise a test? Yes


Each one of those has been tested, a lot. You notice deniers don't actual address the facts of AGW? Don't have a test that shows those facts to be false?
So now you have to answer:
Why do you think trapping more energy(heat) in the lower atmosphere does not impact the climate?

[gebobs]

I have a geologist friend that presented me with the argument that the problem with the man causes climate change hypothesis is that it only looks at a small period , and that most of the change today can be explained by something called milankovitch cycles and presented me this article http://www.paulmacrae.com/?p=62

I love looking at the comments. Someone actually was defending the 51k geologist claim which would be 1% of the Alberta population.

Then there is this...
"Wow. Great article. Especially the part of how millions of years ago the dinosaurs had much more carbon dioxide in its atmosphere and warmer temperatures and yet there was no religious doomsday." Wow, kinda makes ya think, huh?

[werecow]

I have a geologist friend that presented me with the argument that the problem with the man causes climate change hypothesis is that it only looks at a small period , and that most of the change today can be explained by something called milankovitch cycles and presented me this article http://www.paulmacrae.com/?p=62

Is there any response to this sort of argument  ??  If so where can  I find articles that talk about this matter ?  Most of the people against the idea of global warming have been cranks, but this friend is a serious geologist  not just random guy on the internet. Thanks in advance =)

I haven't read the full article yet (I might read it some time over the next few days and give a more detailed response if you want), but the first book I ever read on climate change was written by a Dutch geologist who made a similar argument. In case you're curious, here's a good primer on what Milankovitch cycles are. Skepticalscience.com is usually reliable and based on the peer reviewed literature. They also have a list of most used climate myths. For example, here's an article that addresses the frequently heard point that we're heading into a new ice age because of Milankovic cycles (so note that this argument tells us to expect cooling, not warming, from those same cycles). Not exactly what you need, but pretty close. Here's another post that addresses the idea that the current warming is natural. Many more related tropes in the list of arguments.

Generally speaking, we know that humans are causing the warming for a variety of reasons. The first is basic theory; we know from laboratory experiments that CO₂ is a greenhouse gas. We know for a fact that we are pumping large quantities of it into the atmosphere, therefore something pretty amazing would have to occur for us not to influence the climate. Svante Arrhenius predicted global warming as early as 1896 based on his studies of CO₂. Related is palaeodata, which shows that increased concentrations of CO₂ in the distant past are associated with warmer temperatures (although I should note here that CO₂ was a feedback mechanism as opposed to the primary driver behind such changes, which is why deniers sometimes bring up the "CO₂ lags temperature" canard - but the point is that the temperature variations can't be explained without including the CO₂ feedback). Third, we can take (and have been taking) spectroscopic satellite readings of longwave radiation at the top of the atmosphere, and we can see that, over time, there is increased absorption in the parts of the spectrum associated with CO₂. In other words, CO₂ is "trapping" energy that otherwise would have radiated back out to space. And finally, we have sophisticated models of the climate system that represent the best knowledge we have on the subject. When we use models that only include natural drivers of change (which include Milankovic cycles), we cannot model the temperature changes since the industrial revolution, but we can model temperature variations of earlier periods pretty well. Only when we include human drivers of climate change, can we faithfully reproduce historical temperature trends.

[gebobs]

Doesn't the fingerprint left by the specific isotopes of carbon in the atmosphere indicate that the increase is largely due to "old" carbon i.e. oil, gas, coal?