PhillipS

I think it's been a quiet thread simply because the GIS melt season is just getting started. So far it's been a mild melt season, at or a bit below the long-term average, for the Surface Mass Balance (SMB). From NSIDC Greenland Ice Sheet Today: And the Danish Meteorological Institute (DMI) hasn't started posting data for 2015 yet Of course, SMB is only part of the GIS mass dynamics. Mass loss through glacial melting and calving continues unabated. Here is one recent news article that describes how glacial breakup in 2014 revealed a mountain on the coast of Greenland to actually be an island. From the article: According to glacier researcher Mauri Pelto of Nichols College, the retreat of these two glaciers from 1999 to 2014 has led to several new islands, one of which emerged just last year. In a blog post for the American Geophysical Union, a society representing earth scientists worldwide, the Steenstrup Glacier has retreated by 6.21 miles, or 10 kilometers, during the past 60 years.

Not one of the dusty aged studies you shared is relevant to your claim that 80% of climate scientists reject Marcott et al 2013. Your claim was simply fiction, you know it and, more importantly, we all know it too. But carry on with posting your nonsense - it only hurts your credibility and is immensely entertainingl

It's fun to watch you try to avoid accepting responsibility when you're caught, shall we say, 'embroidering' the facts. In this case you started off by claiming: That Marcott et al study depicting Holocene climate variability is at odds with ~80% of the peer reviewed literature in the paleoclimate arena. The consensus is the globe was at least 1 degree centigrade warmer during the Holocene climate optimum than it is now. But when asked to share a link to four peer-reviewed studies that support your claim you failed to even link to one. Instead you went for the unsupported bluff: Yes, we'll eventually surpass the Holocene climate optimum. We'll need to warm at least 1 - 1.5 degrees centigrade, though. Followed by: Three of the last five interglacials peaked at or above 1.5 degrees centigrade warmer than post-modern era. This is undisputed in the literature. The Holocene optimum wasn't quite as warm, but still peaked early in both the borehole data and the ice core data, well above current/post-modern era temperatures. But of course you know as well as the rest of us that borehole and ice core proxies are regional, not global, so even if 1.5C number were true this was just a bit of misdirection. Then you started moving the goal posts until you ended with: Marcott et al 2013 agrees with the scientific consensus, which is that the HCO was clearly warmer than today, globally. So what happened to your 80% that disagree with Marcott et al 2013? And why haven't you shared even the four peer-reviewed papers you claimed you would? But the more serious issue is that you try to misrepresent Marcott's work to prop up your disingenuous position. As SOC quoted, Marcott wrote: Our results indicate that global mean temperature for the decade 2000–2009 (34) has not yet exceeded the warmest temperatures of the early Holocene (5000 to 10,000 yr B.P.). But that's hardly definitive as to whether today's global temperature is equal or greater than that of the early Holocene. After all, the Earth has continued to warm, and 2014 was the warmest year on record according to NASA.. So let's look a bit deeper into Marcott et al 2013. Below is Fig 3, and its caption, from the paper. The right hand vertical line is the mean for 2000 - 2009, and the anomaly is around 0.45 C from the 1961 - 1990 baseline. The lowest horizontal lozenge is the Holocene temperature spread (roughly -0.2 C - 0.51 C). Note that the Holocene max is only 0.06 C above the 2000 - 2009 mean, so if today's global temps have risen 0.06 C in recent years then we're tied with the HCO max, and if they've risen more than 0.06 C then we've exceeded the HCO. Turns out the answer depends on which global temperature set and which warming trend value you give credence to. But clearly, the Earth does not need to warm much more to exceed the HCO maximum beyond doubt.

Pages magazine is not peer-reviewed, it's an open publication not a scientific journal. None of the articles provide publication history (date submitted, date accepted, and so forth). And when I tried to find some of the articles using Google Scholar they didn't turn up in the search results. Try for yourself and see if you get the same results. Another thing - when I read over the list of papers I saw very few familiar names among those cited, and most of the prominent researchers in the paleoclimate research community were conspicuously absent. Interesting. SOC this was definitely a swing and a miss for you.

All I want are four peer-reviewed global (not regional) Holocene temperature reconstructions that refute the Marcott et al 2013 by showing that the peak global Holocene temperatures were warmer than current global temperatures. That should be a breeze for you, right? Or possibly not. I did a cursory scan of the 198 papers that have cited Marcott et al 2013 since its publication and not one of your alleged 80% have published a rebuttal, or response, or critique, of the Marcott paper. Surely if it were as flawed as you claim at least one of your multitude would have pointed out the errors, if only to prevent others from being misled. Agree?

Well, if you are correct about the 80% then you should find it easy to share four recent peer-reviewed papers that refute Marcott et al 2013. Otherwise, we can confidently assume you're just making things up again.

Nope, you're wrong again. Marcott et al is a multi-proxy reconstruction, not ice core only like your plot. So it is both more representative of global temperature changes and it runs up to where it can be merged with the instrumental temperature record. This is why it gives an accurate indication of global temperature trends for the past 10K years. The only reason to use GISP2 ice core record without providing the contextual meta-data is if you are trying to deceive the readers. Was that your intent?

Do you understand that the most recent data value in the GISP2 ice core is 1855? The last point is 95 years before the present, and the present was defined as 1950 by Dr Richard Alley, who led the ice core analysis team. So the plot you posted leaves off the most recent 160 years or so of the temperature record. That is the period during which most of the AGW warming took place so your plot is disingenuous at best. A better, more accurate, paleoclimate reconstruction would be either Marcott 2013, or Kobashi 2013 (though Kobashi is N hemisphere, not global).

You're correct, SVT, the Greenland melt season is off to a very modest start.

I agree that paywalls are annoying. But if you go to Google Scholar, search for Box Greenland Part, you will find non-paywalled versions of all three papers.

Before you dismiss his findings you should read his papers to see whether you agree with his methodology - there are a number of proxies for glacial extent, such as terminal morraines and sediment cores. Also, annual layer thickness in ice cores can give an indication of snow accumulation - at least for recent decades where compression hasn't obscured the annual record.

Dr Jason Box is a leading researcher on the condition and dynamics of the Greenland Ice Sheet (GIS). He has two blogs on the GIS, www.meltfactor.org, and www.darksnowproject.org, which is focused on his crowd-sourced research project on the causes and consequences of the GIS albedo changes observed in recent years. Dr. Box had a recent post on Meltfactor that I thought might be of interest to the readers here. It deals with possible effects on the AMOC of the large volume of freshwater discharge from the GIS. An excerpt: My contribution was my work of 6 years, a 172 year Greenland mass balance reconstruction published in a 3 part series in the Journal of Climate (Box and others 2013; Box, 2013; Box and Colgan, 2013), enabling Greenland melting to be brought more into context of its ocean thermohaline perturbation. As an aside, the DarkSnow project is currently, April 2015, accepting donations for the 2015 research expedition. I've supported it for the past three years and feel that they are doing cutting-edge research and finding out some surprising things. It's worth checking out.

Here is the CH4 in-situ hourly average data at the Barrow AK observatory. There does appear to be a plume of CH4 in recent months. Looking at just the 2014 to present data makes it clearer. It looks like a series of CH4 events starting last Fall.

Hmmm, so we've switched from taco to bacon strips? Well, bacon is the candy bar of meats, so I've heard.

There is a relevant post on ClimateCrocks today, which includes this excerpt from a Dr Michael Mann column in the Washington Post: You could treat this as ordinary weather, or, you could think about it in a climate context. Counter-intuitive though it may sound, the fact remains that — as I have noted previously — some kinds of winter precipitationcould indeed be more intense because we’re in a warming world. Consider, for instance, that sea surface temperatures off the coast of New England are flashing red, showing an extreme warm anomaly. That’s highly relevant — because warmer oceans have atmospheric consequences. “Sea surface temperatures off the coast of New England right now are at record levels, 11.5C (21F) warmer than normal in some locations,” says Penn State climate researcher Michael Mann. “There is [a] direct relationship between the surface warmth of the ocean and the amount of moisture in the air. What that means is that this storm will be feeding off these very warm seas, producing very large amounts of snow as spiraling winds of the storm squeeze that moisture out of the air, cool, it, and deposit it as snow inland.” Warmer oceans also increase the temperature contrasts that winter storms encounter when they hit the East Coast, notes Mann — and this ups their strength. “Heavy snows mean the temperature is just below freezing, any cooler and the amount would be a lot less,” adds Kevin Trenberth, a climate expert at the National Center for Atmospheric Research. “Warmer waters off the coast help elevate winter temperatures and contribute to the greater snow amounts. This is how global warming plays a role.” It is axiomatic that weather occurs under the climatic conditions of the moment - and AGW has changed some important climatic parameters including global temperatures, SSTs, and atmospheric water vapor. Because of AGW related changes to climatic conditions, every bit to today's weather, good or bad, mild or extreme, is influenced to some degree by AGW. So IMO the question of whether to attribute weather events to AGW should be reframed as: how much influence does AGW have on weather, and how is this influence projected to change as we continue to dump gigatons of GHGs into the Earth's atmosphere?

I think most readers on this forum have read the recent reports of large craters being found in Siberia, and the discussion of their origin. There was a post on the IFLScience website [link] that may be of interest. Here is an excerpt: An expedition from the Scientific Center of Arctic Studies found methane concentrations of 9.6% at the bottom of the crater – 50,000 times the atmospheric average. The possibility that methane released by melting permafrost produced the crater had been a favored hypothesis from its discovery in mid-July. Nevertheless, plenty of other theories were circulating, and scientists urged caution before leaping to conclusions. The extraordinary concentration of methane, on the other hand, seems unlikely to be a coincidence, particularly since methane is slightly lighter than air. The 2012 and 2013 summers on the Yamal peninsular, where the crater is, were around 5°C warmer than normal. Expedition leader Andrei Plekhanov told Nature that the high temperatures probably thawed the permafrost to the point where it collapsed, releasing the trapped methane. If my math is correct, 9.6% is 96,000 ppm, or 96,000,000 ppb (which is how atmospheric CH4 is usually measured). Current CH4 readings at Barrow are around 1880 ppb so the crater levels are alarmingly high. And given that CH4 is lighter than air, those levels aren't the result of CH4 pooling in the deep craters. I think that it would be interesting to monitor the levels on a periodic, say, weekly, basis to learn if the concentration is rising, falling , or stable.

Just saw this on the IFLS FB page and wanted to share:

An honest skeptic would know , when comparing anomaly plots, to check the baselines of each - otherwise the comparison is meaningless. If you really want to compare them then you shift one of the anomaly records by the difference in the baselines. Then, and only then, can you make a relevant comparison. Jonger - do you not understand this or are you now denying basic mathematics, too?

Get over it. The temperature ranks and anomaly plots use two very different baselines. The Divisional Temperature Ranks plot uses a 1901 - 2000 mean as the baseline and the Divisional Temperature Anomalies plot uses a 1981 - 2010 mean as its baseline. Tamino has a post explaining the situation here. Is the fact that the Earth has warmed too much for you to comprehend? As usual, your conspiracy ranting is groundless.

Good luck with the paper! It sounds interesting and I agree that the on-going drought out west could produce major impacts if it continues. When you can, please link to your paper so we can read it, too.

There is a good column on the Shakova paper and global methane trends at RealClimate. The take-away, in my opinion, is that global methane concentrations aren't rising fast enough to be alarming at this time. The rate of methane increase is at least an order of magnitude smaller than what would be needed to significantly affect climate. Here is the conclusion from the column: Shakhova et al (2013) did not find or claim to have found a 50 Gt C reservoir of methane ready to erupt in a few years. That claim, which is the basis of the Whiteman et al (2013) $60 trillion Arctic methane bomb paper, remains as unsubstantiated as ever. The Siberian Arctic, and the Americans, each emit a few percent of global emissions. Significant, but not bombs, more like large firecrackers. So it appears that methane, including arctic methane, is something that we should be concerned about enough to study closely, but it is not alarming as several other AGW effects such as droughts, extreme weather, rising sea levels and ocean acidification.

There is a new report from Dr Shakova about increased arctic methane releases - that the rate of methane release from subsea permafrost has accelerated to 17 teragrams (17 megatons) per year. [Discovery article]. I'll try to track a link to the paper itself. Methane gas bubbles rising through Arctic Ocean water, seen by a remotely operated vehicle.

It's a legitimate question, and one I've wondered about. I've never heard of an overt offer by fossil fuel companies to any of the big name climatologists - but my guess would be that it would come in the form of an offer of funding for their research. A bald offer of money would be too likely to blow up in their faces but an offer of funding could be portrayed as an olive branch to the opposition. "Let's all work together" - that sort of thing.

Blizzard should keep in mind, too that CO2 levels during the HTM never rose above about 280 ppm. As we approach 400 ppm (on our way to 500 ppm or greater) we are pushing the climate into conditions not seen for millions of years. [source] If one understands the GHE and the properties of CO2 and other GHGs it is hard to hope that some unknown 'braking effect' will appear and save us from the consequences of BAU.

Blizzard should keep in mind, too that CO2 levels during the HTM never rose above about 280 ppm. As we approach 400 ppm (on our way to 500 ppm or greater) we are pushing the climate into conditions not seen for millions of years. [source] If one understands the GHE and the properties of CO2 and other GHGs it is hard to hope that some unknown 'braking effect' will appear and save us from the consequences of BAU.