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I'm studying for my exam on Monday. According to my Prof, one should take a break from the material every 20 or 30 min, to increase comprehension and retention. So I decided to read some papers.

If I'm reading this one right, we have about two years until we hit the point of no return (PNR) on climate change.

From: Brenda C. van Zalinge, Qing Yi Feng, Matthias Aengenheyster, and Henk A. Dijkstra. (2017) On determining the point of no return in climate change. Earth System Dynamics, 8, 707–717. https://doi.org/10.5194/esd-8-707-2017

Definitions in the introduction:

Given a certain desirable subspace of the climate system state vector (e.g. to avoid dangerous anthropogenic interference) and a suite of control options (e.g. CO2 emission reduction), it is important to know when it is too late to steer the system to “safe” conditions, for example in the year 2100. In other words, when is the point of no return (PNR)? The tolerable windows approach (TWA; Petschel-Held et al., 1999) and viability theory (VT; Aubin, 2009) approaches and the theory in (Heitzig et al., 2016) suffer from the “curse of dimensionality”and cannot be used within CMIP5 climate models.

For example, the optimization problems in VT and TWA lead to dynamic programming schemes which have up to now only been solved for model systems with low-dimensional state vectors. The approach in (Heitzig et al., 2016) requires the computation of regional boundaries in state space, which also becomes tedious in more than two dimensions. Hence,with these approaches it will be impossible to determine a PNR using reasonably detailed models of the climate system.

Steaming on to the discussion...

Pachauri et al. (2014) stated with high confidence that “without additional mitigation efforts beyond those in place today, and even with adaptation, warming by the end of the 21st century will lead to high to very high risk of severe, widespread and irreversible impacts globally”. If no measures are taken to reduce green house gas (GHG) emissions during this century and if there are no new technological developments that can reduce GHGs in the atmosphere, it is likely that the global mean surface temperature (GMST) will be 4 ◦C higher than the pre-industrial GMST at the end of the 21st century (Pachauri et al., 2014). Consequently, it is important that anthropogenic emissions are regulated and significantly reduced before widespread and irreversible impacts occur. It would help motivate mitigation to know when it is “too late”.

In this study we have defined the concept of the point of no return (PNR) in climate change more precisely using stochastic viability theory and a collection of mitigation scenarios. For an energy balance model, as in Sect. 3, the probability density function could be explicitly computed, and hence stochastic viability kernels could be determined. The additional advantage of this model is that a bi-stable regime can easily be constructed to investigate the effects of tipping behaviour on the PNR. We used this model (with the assumption that CO2 could be controlled directly instead of through emissions) to illustrate the concept of PNR based on a tolerance time for which the climate state is non-viable. For the RCP scenarios considered, the PNR is smaller in the bi-stable than in the mono-stable regime of this model. The occurrence of possible transitions to warm states in this model indeedcause the PNR to be “too late” earlier.

The determination of the PNR in the high-dimensional PlaSim climate model, however, shows the key innovation in our approach, i.e. the use of linear response theory (LRT) to estimate the probability density function of the GMST. PlaSim was used to compute another variant of a PNR based only on the requirement that the climate state is viable in the year 2100. Hence, the PNR here is the time at which no allowed mitigation scenario can be chosen to keep GMST below a certain threshold in the year 2100 with a specified probability. In the PlaSim results, we used a viability region defined as GMSTs lower than 2 ◦C above the pre-industrial value, but with our methodology, the PNR can be easily determined for any threshold defining the viable region. The more academic case in which we assume that GHG levels can be controlled directly provides PNR (for RCP4.5, RCP6.0, and RCP8.5) values around 2050 (Sect. 4.2). However, the more realistic case in which the emissions are controlled (Sect. 4.3) and a carbon model is used reduces the PNR for these three RCP scenarios by about 30 years. The reason is that there is a delay between the decrease in GHG gas emissions and concentrations. my emphasis... I was reading this and went "wait, wuh?...

Although our approach provides new insights into the PNR in climate change, we recognize that there is potential for substantial further improvement. First of all, the PlaSim model has a too-high climate sensitivity compared to CMIP5 models. Although in the most realistic case (Sect. 4.3) we somehow compensate for this effect, it would be much better to apply the LRT approach to CMIP5 simulations. Second, in the LRT approach, we assume the GMST distributions to be Gaussian. This is well justified in PlaSim, as can be verified from the PlaSim simulations, but it may not be the case for a typical CMIP5 model. Third, for the more realistic case in Sect. 4.3, we do not capture the uncertainties in the carbon model and hence in the radiative forcing.

A large ensemble such as that available for PlaSim is not available (yet) for any CMIP5 model. However, we have recently applied the same methodology to two CMIP5 model ensembles, i.e. a 34-member ensemble of abrupt CO2 quadrupling and a 35-member ensemble of smooth 1 % CO2 increase per year. The CO2-quadrupling ensemble was used to derive the Green’s function, and then the 1 % CO2 increase ensemble was used as a check on the resulting response.

The probability density function of GMST increase is close to Gaussian for the 1 % CO2 increase ensemble but clearly deviates from a Gaussian distribution for the 4x CO2- forcing ensemble, particularly at later times. Although the ensemble is relatively small and the models within the ensemble are different (but many are related), the results for the LRT-determined GMST response (Aengenheyster, 2017) are surprisingly good. This indicates that the methodology has a high potential to be successfully applied to the results of
CMIP5 model simulations (and in the future, CMIP6). The applicability of LRT to other observables than GMST can in principle be performed, but the results may be less useful (e.g. due to non-Gaussian distributions).

Because PlaSim is highly idealized compared to a typical CMIP5 model, one cannot attribute much importance to the precise PNR values obtained for the PlaSim model as in Fig. 7. However, we think that our approach is general enough to handle many different political and socioeconomic scenarios combined with state-of-the-art climate models when adequate response functions of CMIP5 models have been determined (e.g. using LRT). Hence, it will be possible to make better estimates of the PNR for the real climate system. We therefore hope that these ideas on the PNR in climate change will eventually become part of the decision-making.

so, yeah, if I'm reading this wrong, that would be good to know
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Almost a decade ago, James Lovelock said that he thought climate change would be good for us in the way that WWII was good for Great Britain, that is, everyone will pull together and work toward the common good.

James Lovelock is a bit of a nut.

I've been thinking about this, about US response to real or perceived shrinkage of resources, and how different societies will deal with fewer resources. We have lots of food now. Lots and lots. But over the next decade, the cost of food will rise significantly. I think that within the next decade, there's a good chance that it'll go back to historical levels, more in line with the cost of food world wide. That means that the cost of what Usians buy now will almost double, from the average of 12% we spend today to 18% - 20%. And that's the average; 90% of Usians will be paying much more of their discretionary income for food.

As the cost of food goes up, and the availability of some things like coffee and bananas decreases, folk will become resentful, and the ones closer to the bottom will become very afraid. People who are honestly afraid do some crazy shit, like vote to take food away from someone else' children.

Or more like, slowly vote to take away services like after-school programs, well-child visits, psychological services, and on and on, until you get to everybody for themselves. It's like how the body will sacrifice internal organs, the liver or the kidneys, to send blood to the brain. The problem being that you can't live without your liver or kidneys.

Doug Sanders wrote in this Globe and Mail piece: "Sri Lanka, for example, is also experiencing a drought this year – its worst water shortage in four decades, one that has wiped out the entire year’s rice crop. Yet nobody in rice-dependent Sri Lanka is starving: The government simply spent $350-million to import enough rice to make up to for the losses. This hurt the Sri Lankan currency, but the economy has kept growing and people are eating."

Instead of being reassured, I wonder how often Sri Lanka will be able to do this?

On top of drought, we're looking at about 1.5" of sea level rise per year over the next ten years, which doesn't sound like much, but that's 15" in ten years, which is a hell of a lot. Between heat and drought in the desert states to flooding on the coasts, millions of people will be forced to relocate. You can think of it as a hundred Katrinas, stretched out over a decade, one after another. Most of those folks will have lost not only their jobs, but all the equity of their property.

Pulling back to look at the big picture, I can imagine that as the cost of food goes up and people have less discretionary income, they won't be getting that new phone or that new pair of jeans. And they won't be able to go grab a burger, because just the adult sandwich is gonna cost $10-$15, let alone the fries and the coke. And though minimum wage is edging up in some places, I don't expect it to double over the next ten years. Especially these next ten years.

According to the internet, the US has about 3,750,000 or so people working in fast food. I think that industry is gonna tank, and that there's not going to be a whole lot of jobs around for the two or three million people who'll be out a job. And of course, if won't just be these guys out of a job. Every other industry that depends of high levels of discretionary money spending will be firing staff -- clothing, books, toys, tourism. Millions and millions of people out of work, and even more, and those with fewer safety nets, in other parts of the world.

All of this at once. Now. Politically, policy-wise, I wonder what that will look like.
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I was talking to one of my coworkers about climate change. It was an idle conversation, nothing too deep. I'm always surprised, though, about how people conceptualize it -- in this case, a kind of shruggy "yeah, that's gonna be a problem" kind of way.

We just experienced a new low Arctic ice maximum -- 13.878 million km2. In comparison, the maximum in 1979 was over 16.5 million km2, a decrease of about 17%, or about 4% per year. I figure we've got about another 20 years or so before we have a winter ice-free arctic.

I'm pre' damn sure that most folks have no idea to the chaos that will bring. What it is, is people gotta eat.

I'm reading a paper right now entitled Earth's changing global atmospheric energy cycle in response to climate change." It is dry. I will sum up:

Ed Lorenz is the guy who came up with the idea of the Butterfly Effect. As cool as that is, more importantly, he came up with the equations that define the potential and kinetic energy in planet atmospheres. His atmospheric equations were also applied to the hydrological cycle, and to equations figuring out stuff like wind energy.

Anyway, we call the conversion of this atmospheric kinetic, potential, and mechanical energy, and how that energy effects atmospheric circulation (which effects weather and climate) the Lorenz energy cycle.

Though there's been lots of study replicating and validating Lorenz's equations, study of the long term, over-time characteristics of the energy cycle are lacking. In this paper, the authors found some nifty super-scientific NASA satellite records, and got them to pasted together with a computer program that lets them see the data as an uninterrupted set that runs from 1958-2013.

"More details of computing the energy components of the Lorenz energy cycle of the global atmosphere are provided in the sections on Methods." (as Madmartigen said, "Tempting!")

Lets instead go right to the discussion. What they say is that when you add energy to a planet, the atmosphere jiggs up like a high-schooler buzzzed on a six-pack of redbull. That is, the authors are able to show strong positive trends of potential energy over the Asian continent in the Northern Hemisphere.

"The positive trends of potential energy in Central Asia, especially in West-central Mongolia, are associated with the increasing droughts in these areas, because the increasing droughts can magnify the temperature perturbation and hence cause the increase in potential energy. The two data sets also show the relatively weak positive trends over the eastern Pacific Oceans. Such positive trends are related to the intensifying tropical cyclones with global warming."

But beyond that, what I was really fact mining for was this one sentence: "Therefore, the positive trends of C(PM,KM) are due to the expansion of the Hadley Cell in the past 35 years, which was revealed in some previous studies."

Expansion of the Hadley cell, dudes. Are you still with me? As the Hadley cell moves north, the sub-tropical dry zones move with it. Heat, too. Right into the worlds various bread baskets. And when it does rain? Vicious storms that will likely smash what crops that folk were able to grow.

It's what the models and guys like Jim Hansen have been saying for about a decade, but now we have more than models.
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What with my stressful schedule and all, I haven't been on LJ or DW much at all. I've also not been spending much time reading over the arctic news -- I just know that it's all bad. And fascinating -- it's really amazing to watch, how something as big as the whole Earth system can change so quickly, in a lifetime.

From this entry at Neven's Arctic Sea Ice Blog

One of the scientists writes: "I'm expecting the peak in extent in the next week or so. What that will do for volume numbers I'm not so sure. I guess it depends on how fast the ice starts to drop.

Judging by the way 2017 is below the curve, I would say that it should peak in volume no later than mid April. Which will be another large departure from the norm." -- NeilT

So far, famine has been declared in South Sudan, where war and a collapsing economy have left some 100,000 people facing starvation there and a further one million people are classified as being on the brink of famine. More than 10 million people in Ethiopia need food aid due to the worst drought in more than 30 years, and neighboring Somalia where 4.7 million people (40 percent of the population) need food aid -- "war has joined forces with nature to plant the seeds of disaster." In Kenya, severe drought, failed harvests and Government’s poor preparedness are causing a food security emergency for 10 million, or about 1/5 of it's population.

In 2002, sometime before Mike went off to Iraq, I woke from a dream of flames, and a voice was saying, "It wasn't the change in climate. It was the wars that killed us."

I try to get it organized in my mind -- This is what the scientists were telling us, this is what was observed, this is what the politicians said, this is what my neighbors said, this is what I read in the newspapers.
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"A simplified way to think of extent versus area is to imagine a slice of swiss cheese. Extent would be a measure of the edges of the slice of cheese and all of the space inside it. Area would be the measure of where there is cheese only, not including the holes. That is why if you compare extent and area in the same time period, extent is always bigger." -- National Snow and Ice Data Center FAQ

Read more... )
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screen shot from original page

New page is here

Provide feedback here

I haven't put in my feedback yet. Need to think on it to provide something that sounds like more than just raving.
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You have ever been a herald of woe. Troubles follow you like crows, and ever the oftener the worse. I will not deceive you: when I heard that Shadowfax had come back riderless, I rejoiced at the return of the horse, but still more at the lack of the rider; and when Eomer brought the tidings that you had gone at last to your long home, I did not mourn. But news from afar is seldom sooth. Here you come again! And with you come evils worse than before, as might be expected. Why should I welcome you, Gandalf Stormcrow?

Being a climate scientist right now really sucks. Most people have heard about the questionnaire sent to the US Environmental Protection Agency, but I can't imagine anywhere that climate scientists are having a good time right now.

Neil T, on Neven's Sea Ice Forum says it well -- Re: The 2016/2017 freezing season Reply #1330 on: December 12, 2016, 02:49:17

"Guys, before I came here, in fact before there was a "here" to come to, I spent a lot of time at RealClimate and I got a feel for what the climate scientists are trying to do with their assessments.

In short the statements above seem to lead us to believe that the scientists are deliberately misleading us for some reason. After all it's blindingly obvious that it's not going to be the latter half of the 21st century before the ice goes.

But, in fact, it might just need a scientist and especially a climate scientist, to fail to see that.

Over and over again, during the debates, Gavin Schmidt has been seen to say that these annual variations must be ignored if we are to see the larger picture. And he's right, the larger picture is 100 to 1,000 years.

So what they do is bury the annual variations in decadal averages and then bury them again in multi decadal averages. Truth be told, if you take the 30 year running mean, we're pretty much on target. When you look at the 2000's averaged out. Even the 2010's, when the decade is done, will be averaged with the previous two decades to create the 30 year running mean.

The problem with this methodology, which is used by all climate scientists when they report to the IPCC, is that it fails to anticipate, or even detect, step changes when they happen. In fact it's designed to do exactly that, remove them.

The major problem with that approach is that what is happening to the Arctic is massively driven by annual variations and those variations are getting larger as every decade goes by. By the time that the 2010's annual variations are released from the 1990's, it will already be blindingly obvious to everyone that they are out of touch. Also the model will mitigate to tone down even those effects.

In reality the 30 year running mean has been a wonderful ruler for measuring future change over the last 5 decades. It' was extremely useful in the denialist rantings in the aftermath of the 97/98 nino and the return to the norm which happened there. It forced the denialists to take out the 97/98 as a baseline and then their entire assertions fell apart.

So, I think, when railing at the "Scientists" for not predicting what we are seeing now, I respectfully submit that their models and their projections are specifically designed to ignore it. Because, so far, by ignoring it, they have been more right than wrong.

Honestly I feel that an ice free arctic in 2022 will force them to reassess that. Because the possible forcings created by the black swan event are enough to overwhelm the 30 year running mean and to continue with it would be foolish. They would need to create a new baseline and then run a parallel comparison and draw conclusions that way.

Getting scientists to throw away long held and very good baselines will take an extreme act. The same extreme act we see evolving before us in an unprecedentedly warm winter with unprecedentedly low ice volume and extent.

What I'm saying is "Don't allude motives to the Climate scientists just because they are not monitoring the same thing you are". Because, in the end, these people have been in the firing line for a long time and the vast majority of them are both honorable and extremely thick skinned. But, believe me, they have feelings too."

And this follow-up -- Re: The 2016/2017 freezing season « Reply #1339 on: December 12, 2016, 12:24:36 PM »
Ninebelowzero December 12, 2016, 09:42:52 AM

Whatever the scientific approach scientists, regardless of whoever is paying for the research, should stop talking to politicians in terms of 'mitigating' change and just tell them what we need to stop doing however politically painful it is.

For reference to how well that works, have a look in the RealClimate posts around the time of the Copenhagen climate summit. To paraphrase the scientists, they told the politicians what their certainty meant, how it worked and what should be done.

The politicians looked at the figures and said, paraphrased

"Come back and tell us when you are 100% certain but you'll have to have EVIDENCE mind. then you can tell us what we need to do!".

Can you imagine how they felt? They had, in some cases, spent years on this, some intruding heavily into their family lives to do so.

Essentially the politicians said "When the roof falls in tell us what to do". Of course the answer is "Put your head between your legs and kiss your ass goodbye".

Many of those scientists involved in Copenhagen refused, ever, to have anything to do with a climate summit again.

well said

Dec. 12th, 2016 11:52 am
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From the Arctic Ice Blog:

"No one can predict the future, especially when data about the present is so fragmented and incomplete. But we have one data point that cannot be denied nor overlooked: the planet is very old and has been relatively stable for billions of years, in spite of some extraordinary shocks. I believe the engineering jargon for this condition is "robust". The surface configuration and conditions may change over time, but there do seem to be mechanisms that tend to push it back into equilibrium. Runaway excursions don't seem to happen, but there do seem to be long range cycles, and we seem to have initiated the latest, and it may be severe.

The safest bet to make is that we have messed with the climate, and there is a possibility that our agriculture will be affected as a result, and along with it our industry and population distribution. The tertiary effects will be conflict, civil strife, economic distress, famine, waves of refugees, perhaps war. We may already be seeing the first of these changes manifesting themselves. The changes have been slow up to now, but they will probably speed up in the near future, and become more severe. How severe yet remains to be seen, and the time scale is not clear.

All we know is that the situation is not necessarily catastrophic. Even if it can't be reversed, or even stopped, perhaps it can be mitigated, and it stands to reason that the sooner we start the better." -- Elisee Reclus

I believe that the trick will be surviving those tertiary effects.
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"Quick and easy: U.S. Rep. Lamar Smith, Chair of the House Committee on Science, Space, and Technology—and climate change denier—has a one-question survey on his website about congressional priorities for the year. Please select Other and write in "climate change mitigation" or "fight climate change," something like that. Do it and then COPY AND PASTE in a new status (don't share or it will only be viewable by my friends) and share the hell out of this post."
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Neven Curlin, who writes the Arctic Sea Ice Blog is taking a sabbatical.
"I'm really going to take a break from blogging, as I have been struggling with an Arctic burn-out since 2012. On the one hand it's caused by everything that has been and still is going on in the Arctic. The learning curve, the excitement, but most of all the depression that comes with watching this steamroller just plough forward, is taking its toll." Neven, full post here

One thing that Neven left us with is the Sea Ice Forum. I'm going to start posting some quotes from there, because it helps me organize it in my head. I'll put it under a cut for the folks who aren't into watching this disaster; there are so many disasters going on right now. I'll tag these posts with "asif".

Read more... )
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What's happening in the Arctic right now will effect the future of all humans -- as in, if we're going to make it out of this century alive.

Here are the Cliff Notes to the new study Arctic Resilience Report. There is a very good graphic on page 80, Fig 3.3.
Read more... )
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-- Burning Earth Radio, November 2016 youtube

"There's three cyclone activity areas in the arctic; you have one off the north coast of Iceland, one strong one off the north coast of Norway, and another one up here at the north pole. There's a lot of strong winds associated with these cyclones.

We have a lot of wind activity at the surface associated with these cyclones. We can see why we're getting these winds -- we have all of this warm water coming up in the gulf stream coming up and pooling in the arctic. We have extremely warm waters here, hot spots up to 9.9C warmer than normal and very large warm pools 1.1C-2C above average. And what it's doing is bringing a lot of warm air with it, up into the arctic.

What's happening is that these low pressure areas are pulling cold air down off the arctic. Now you have the cold air pulled off the Greenland ice sheet, drained off Siberia...You can see this going back to the temperature map, you have the cold air extending into the southern latitudes here, and warm air extending very high into the arctic.

With a lot of these strong winds, you're going to get a lot of breaking up of the sea ice. You can see that a lot of this air is carrying a lot of moisture. What this is doing is that this is creating a lot of strange rain events in the arctic... We can see that there's this jet of precipitable water in the air that's coming up over Europe and getting pulled into the arctic, bringing rain.

With these high winds, these storms, we have a lot of wave action. For example, 4.5 meter waves off these Russian arctic islands, 9.9 meter waves off the coast of Norway, 3.9 meters near the north pole -- these are very big waves.

These waves are causing a lot of problems for the sea ice in the arctic. We have the warm water, a lot of wave activity -- the sea ice just doesn't have a chance. Looking at the sea ice graph, we can see is that the sea ice isn't doing too well this year. The sea ice is basically crashing, running into this brick wall of cyclone activity and warm air that's being pulled up into the arctic.

A lot of the air in the arctic this November is 20C warmer than average. Don't be fooled that 1C or 2C average warming doesn't make a difference.

These cyclones in the arctic -- we're only going to see more of this as the Earth warms. Eventually, this whole warm anomaly is going to connect across the arctic basin, and we'll see a lot of these storms raging around the arctic."
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This is the first time I've heard an actual Important Guy speak about climate change. Yesterday Dr. David Titley spoke at Central Michigan University in Mt. Pleasant, an hour's drive away.

As he's a military guy, his presentation had me looking at things that I usually don't read much about. I mean, I come from a military family and Mike is a 20-year man, so it's not all new, but I got a few slides that I don't usually see. And he talked about the senate hearing with Ted Cruz, and that was fun.

Mostly, like these things usually are, it was "Hey, this is a real and serious problem. We've got to get together on this." -- so it was all head-noddy stuff.

At the end he took questions, and my question was the last one: "My husband and I are in our mid-50's, I'm a nurse and he's a truck driver. We're just average people with a bucket of kids and three buckets at grandkids. About ten years ago, we started talking about climate change and how it was going to effect us. My question is: do you have kids, grandkids? What do you think of when you think of them?" Surprising to me, my voice broke at the end. "What do you think when you're staring at the ceiling in the middle of the night?"

His answer was that no, he doesn't have any kids. And his advice was that we educate our kids and make sure that they vote. Which is a fair enough answer, but not what I was looking for. I wanted to know his gut.

Then folks started picking up their coats and moving into the isles. Mike and I sat for a bit, and he patted my knee.

And they started coming, from this direction and that, a stream of older women -- pressing my hand and patting me on the shoulder and even giving me little hugs.

"Yes," they said, and "Are you okay?" and "Well, honey" and little murmurs and of this and that. It was wonderful and a little overwhelming. A woman of about my age, but in much nicer clothes *g*, slipped her card into my hand, Elizabeth Dell, Great Lakes Regional Coordinator of the Citizen's Climate Lobby.

You'd think that I'd already be involved with the Citizen's Climate Lobby, but no. I just ... I didn't think I'd have the resolve to keep pecking away at something that I don't think will change. Perhaps hearing Titley, knowing that there are some very big players in the government who are concerned about this, makes me more willing to spend time and energy in adding my small voice.
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As expected, this year Global C02 measurements failed to drop below 400 ppm for the first time in the history of the homo sapiens.

It will not pass below this level again in our lifetimes.

Trends in Atmospheric Carbon Dioxide
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Michael Mann: (...) it’s unfortunate that some in the weather community are not providing that critical context for understanding this trend towards increasingly devastating tropical storms and hurricanes. Matthew is a very good example of a storm that was unique, unprecedented, in certain respects. It intensified far more quickly than any other storm that we’ve seen in modern history, basically going from not even a tropical depression to a near-hurricane-strength storm over the course of, you know, less than half a day, and then, the next day, of course, strengthening into a major hurricane, a Category 5 hurricane. It’s weakened a little bit, but now it’s restrengthening.

And where that intensification, where that rapid intensification occurred was in the region of the Caribbean that has the greatest heat content, not just that the ocean surface temperatures are warm, but there’s a very deep layer of warm water. And that’s important, because that helps sustain these storms as they churn up the ocean. The churning doesn’t bring cold water to the surface to weaken the storm, if there’s a deep layer of warmth. And that all has a climate change signature with it, not just the fact that the ocean surface temperatures in the Caribbean are at near-record levels, but the—just the sheer depth of that warm water is unprecedented. And as the surface warming penetrates into the ocean, we are seeing increases in ocean heat content. Last year was the warmest our oceans have ever been on record. And that’s critical context. It’s that warmth that provides the energy that intensifies these storms. And it isn’t a coincidence that we’ve seen the strongest hurricane in both hemispheres within the last year.


Governor Rick Scott of Florida has received quite a bit of funding from the Koch brothers over the years. He is a climate change denier. So here you have a state which is on the front lines of dealing with the impacts of climate change, and not just because of the possibility of more extreme weather events, more intense hurricanes, a trend that we see and a trend that we know is related to climate change, but you combine these intensifying storms with the rising sea level, and, forgive the pun, you get a perfect storm of consequences for coastal flooding. And we’re going to see exceptional coastal flooding associated with Matthew, not just because of the intensity of the storm, but because of the fact that sea level rise has added substantially to the impact of storms like Matthew. So there’s this amazing hypocrisy ..."

Amid Media Blackout over Climate Change Links to Hurricane Matthew, Top Scientist Speaks Out
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"Some of the models suggest that there is a 75 percent chance that the entire north polar ice cap during some of the summer months will be completely ice-free within the next five to seven years." Al Gore, U.N. Climate Summit, Copenhagen, 2009

Well, we'll end up at about 4000 km3 for the 2017 minimum, compared to the historic (1950-1990) value of about 7500 km3. So it's going slower than we worried it might.

However, this year, we have an ice-free north pole:

From the Canadian Cost Guard twitter feed, the scientific ship and ice-breaker, Odin, at the geographical North Pole, August 28, 2016.

I am thankful that we aren't yet ice-fee. But I don't think it will be long now.
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The "Wrangel Arm" in the arctic ocean, from Aug 2 to Sept 2, 2016:

"First, since the summer sea ice was also shrinking, this meant that the summer ice cover had lost something like 60 per cent of its volume between the 1970s and the 1990s, a far more drastic and dramatic loss than one would have suspected without taking account of the ice thickness. At this rate the summer ice would disappear fairly early in the coming twenty-first century. The world needed to be warned, and we did our best to warn it. But not only did the politicians and industrialists not want to know, neither did the scientific modelers. They continued to run unrealistic models which forecast that sea ice would remain substantially undiminished right up to the end of the twenty-first century. The UK Meteorological Office still clings to these impossible predictions. Nature would soon prove them wrong."

A Farewell To Ice, p. 69, Wadhams 2016

"A mild winter, early opening up, extreme low snow cover, probably caused the Arctic to soak up enough heat to not care about the June and July sun. And who knows, maybe a pulse of warm water - extremely difficult to measure - from the Atlantic and Pacific continued the long-term process of complete Arctic sea ice loss.

The world hasn't experienced the warmest average global temperatures on record for three years in a row for nothing. This heat eventually ends up in the Arctic."

-- Neven Acropolis, Sea Ice Blog, PIOMAS September 2016
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There's a chance that this year we'll see our first ice-free north pole in recorded history.


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September 2017

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