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bdgwx

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  1. November mean extent came in at 9.81e6. This is lower than my estimation of 9.9e6 from my earlier post. Extents are hugging the lower interdecile range of the 1981-2010 average. Even assuming we hit the climatological average for December of 12.8e6 (I don't see how that's possible at this point) then 2018 will easily land in the top 5 lowest for annual mean extent. If December comes in at a more modest (but still high by recent standards) 12.4e6 then 2018 could make a run for the second lowest behind only 2016.
  2. It was taken with my Google Pixel 2 using the new night mode. The pictures this thing takes are awesome. Sent from my Pixel 2 using Tapatalk
  3. This is a picture of the tornado near Havana/Easton.
  4. I believe this figure is in reference to TSI which is incident radiation normal to the beam angle. To get the integrated radiation over the entire Earth you have to multiple by Earth's cross sectional area. Conveniently the cross sectional area of a sphere is 1/4 the surface area. That means the power going into the geosphere is actually 1360 / 4 = 340 W/m2. So you need to take that -8.0 W/m2 and divide it by 4 as well. This gives us a normalized value of -2.0 W/m2 of force that's being applied. Note that Zharkova's super grand solar minimum claim is 4x the magnitude of the Maunder Minimum (a fact she acknowledges). So will this hypothetical Modern Minimum really be 4x as deep as the Maunder Minimum? Maybe. But, I'm not going to hold my breath. Furthermore, I believe this is the maximal effect. It's not the mean forcing you'd derive if you integrated the radiation reduction over the several decades in which the minimum is taking place. Remember, it will slope down on the entry and slope up on the exit. And of course, this in no way turns off the CO2 effect. It's persistent positive radiative forcing effect is still very much in play. And it will remain in play (unless we go to a negative CO2 emissions regime) for 100s or even 1000s of years easily outlasting this hypothetical grand minimum.
  5. Again...no one is suggesting that the total effect of CO2 is larger than the total effect of the Sun. What we are saying is that the change in the effect of CO2 is larger than the change in effect from the Sun relative to the preindustrial era. Also, the Rahmstorf study regarding a hypothetical grand minimum and it's effect on the climate isn't the only one available for you to review. I posted 3 others above. Finally, if you're going to include oceanic composition in your list then it would be imperative to also include atmospheric composition. Afterall, the Stefan/Boltzmann law tells us that the Earth should be radiating with a temperature of 255K, but because our atmosphere traps heat it actually radiates at 288K which is a +33K effect. The atmosphere matters...a lot. Changes in its composition can and do have a measurable effect.
  6. CO2 like most polyatomic molecules really does have it's molecular vibration modes activated by photons with wave number 667. This process converts quantized photon energy into thermal energy. And it's been confirmed by laboratory experiments going as far back as Tyndall in the mid 1800's, modern infrared spectroscopy, paleoclimate records, and fully explained by molecular physics and quantum mechanics. This is reality and it's been known for over 150 years. My phrasing "all other things being equal" is a nod to the fact that there are many physical processes that act as agents to force global heat uptake changes beyond just greenhouse gases and solar radiation. It's the net effect of all of them that determines the magnitude and direction of the "force" placed on the climate system.
  7. The climate in the midwest is a bit tricky because it is (or at least has been) effected by anthroprogenic forcing agents that are completely unrelated to global warming. Refer to Alter et. al. 2017 for information on how agricultural significantly altered the climate in the midwest. The scientific consensus has never been that polar ice would be gone by now. In fact, the consensus has actually had an embarrassing history of underestimating Arctic sea ice declines; the region and metric most relevant to this myth. A good illustration of this is IPCC AR3 published in 2001 in section 7.5 where they discuss predictions of the cryosphere. They say "The simulations of ice extent decline over the past 30 years are in good agreement with the observations, lending confidence to the subsequent projections which show a substantial decrease of Arctic sea-ice cover leading to roughly 20% reduction in annual mean Arctic sea-ice extent by the year 2050." and then show computer simulations of the expected trajectories. I'll leave it as an exercise for you to compare these simulations with observations after 2001. Also note that "climate change" or at least the slight variant "climatic change" actually predates "global warming" in the scientific literature. And ironically both terms are believed to have had their first appearance as scientific vernacular by the same person, Mitchell, who was a climate scientists publishing research as early as the 1950's. It should also be noted that Swedish and Nobel prize winning chemist Svante Arrhenius had been using phrases like "raising the temperature of the earth's surface" in the context of the greenhouse gas effect and specifically CO2 as early as 1896! Refer to Arrhenius 1896 and Rodhe et. all 1997. And speaking of Arrhenius...he actually figured out some important concepts in regards to global warming including the water vapor feedback, the more aggressive warming in the polar regions, and the fact that the oceans help mitigate anthroprogenic CO2 forcing by scrubbing out some our CO2 emissions. And this all happened in the 19th century (as in prior to 1900) over 120 years ago and long before modern physics (general relativity and quantum mechanics) became a thing.
  8. Hmm...I think there may still be some confusion here. When we say "forcing" we are talking about a perturbation or anomaly above or below a reference point. For example, a solar grand maximum might have +1.0 W/m2 of "forcing" relative to a long term average. A solar grand minimum might have -1.0 W/m2 of "forcing" relative to the same long term average. Likewise, CO2 "forcing" is relative to a reference point. Typically we use the 280 ppm preindustrial concentration as the reference point. There's actually a coincidental and rather convenient temporal alignment of these two reference points as a result of the Sun being midway between the Maunder Minimum and Modern Maximum just before the CO2 concentrations spiked up from 280 ppm. A "forcing" in this context is a change. We aren't saying that the total effect of CO2 is more powerful than the total effect of the Sun. What we are saying is that the change in the CO2 effect is bigger than the change in the Sun effect today. So if the Sun goes -1.0 W/m2 and CO2 goes +2.0 W/m2 and all other things remain equal then the net effect is +1.0 W/m2. This is because the change in the CO2 effect was bigger than the change in the Sun effect.
  9. That is not what bluewave or anyone has claimed. The claim is that Sun (like any main sequence star) is relatively stable in regards to it's luminosity. The variability in the radiative forcing is relatively small despite the magnitude of the radiative forcing being large. The change in radiative forcing of CO2 dominates over the change in radiative forcing of the Sun. Again, it's the change in the effects that are crucial in understanding the change in radiative forcing and thus the change in the heat uptake by the geosphere. Note that I have underlined change to drive home the point that it is the change in the system that puts pressure on the climate and ultimately the Arctic sea ice extents to also change. For example, if the Sun were to experience a change of 0.25% in it's integrated luminosity then this is equivalent to 1360 W/m2 * 0.0025 / 4 = 0.85 W/m2 of forcing. But, a doubling of CO2 results in 5.35 * ln(560/280) = 3.7 W/m2 of forcing. That's more than 4x the effect. Plus, solar grand minimums are relatively short term compared to the long term impacts of CO2 which take 100s or even 1000s of years to die off to preindustrial levels. Note that a -0.25% change in TSI is considered to be on the high end of the forcing change for a hypothetical grand minimum.
  10. And it's not just Rahmstorf that came to the conslusion that grand minimums will have minimal effect. You also have Meehl 2013, Anet 2013, and Jones 2012. Yes a hypothetical grand minimum will suppress the warming, but it won't stop it and it will only be temporary. Once the Sun comes out of its quiescent state that mitigation effect completely disappears.
  11. I think the inertia lag that creates the difference between transient climate response (TCR) and equilibrium climate response (ECR) is due to the heat flux process between the atmosphere and ocean. TCR and ECR are measures of atmosphere warming...I think. The idea being that the radiative forcing, whatever it may be, is fully incorporated into one of the heat storage mediums in the geosphere immediately. Afterall, it has to go somewhere. The ocean is what takes it up immediately. This creates an imbalance in the temperature between the ocean and the atmosphere. That imbalance takes 20-40 years to equilibriate once the radiative forcing returns to 0. The ECR-to-TCR ratio is somewhere in the neighborhood of 1.2 and 1.4 depending on who you ask. This is why 1.0C of warming in the atmosphere means that we are likely already committed to 1.2C (at least) of warming even if all CO2 emissions cease immediately. The radiative forcing of CO2 should be about 5.35 * ln(410/280) = 2.0 W/m2 right now. However, it isn't constant. Integrating the period of the study in question here from 1991 to 2016 (which is 355 ppm to 404 ppm) gives us a mean radiative forcing of 1.6 W/m2. However, there are other radiative forcing agents in play including other GHGs, aerosols, etc. I think (though I'm prepared to be wrong about this) that all of the non-CO2 forcing agents tend to net out to 0. Sure, there is CH4 and other GHGs to consider but aerosol cooling offsets these...mostly...I think. I guess this is kind of convenient that it works out this way. Trying to infer values from IPCC AR5 the net effect they estimate (after my inference is applied) from 1991 to 2016 looks to be around 1.6 W/m2 total which is right at what the CO2-only forcing is. So even if this study backed by the ARGO data are to be believed we're still missing about 0.7 W/m2 or so of forcing to fill the gap to 1.6 W/m2. I think Pinatubo 1991 can explain some of the difference. And there were I think 15 or so VEI 4+ eruptions during this period which likely played a role at offsetting a lot of the CO2 effect. And I have a suspicion that the severely underestimated Arctic ice melt took up a lot more than expected as well due to the stupidly high enthalapy of fusion (334 j/g) vs the specific heat capacity of oceans (4 j/g). If someone has an updated breakdown of where the radiative forcing went that would really help me personally. I'll see if I dig some of this information up.
  12. So in a nutshell it from 1.33e22±0.20 j/yr to 1.21e22±0.72 j/yr. The result did actually change some, but the biggest change was with the margin of error. Assuming I did the math right 1.21e22±0.72 j/yr gives us 0.75±0.45 W/m^2 over the entire Earth. Normalized to the surface area of the ocean only this would yield 1.05±0.63 W/m^2. The IPCC estimated that the ocean took up 0.55 W/m^2 (ocean area only) from 1971 to 2010. [IPCC AR5 ch. 3, pg. 264] The IPCC estimated that the ocean took up 0.71 W/m^2 (ocean area only) from 1993 to 2010. [IPCC AR5 ch. 3, pg. 264]
  13. Sorry about that. My post wasn't meant to be critical of you. Actually it wasn't even in response to anything you said at all. My post was in response to what I'm seeing in these "internet sources" going crazy right now saying the entire process of publishing in peer reviewed forums is corrupted and broken beyond repair and that everything science produces is now tainted all because of this one mistake. I'm even seeing claims that this mistake proves the oceans aren't even warming at all. So yeah, these "internet sources" are a huge problem right now. This incident is proof that science is self correcting despite the bumps and bruises that happen along the way. Anyway, back on topic. I still think their method is a pretty cool idea. Though I concede I don't really fully understand it. I read the paper and I have to be honest, that was pretty thick stuff. And from what I understand of the mistake it wasn't with the technique per se. It was with the statistical math used to put error bars around their result. The result itself wasn't really challenged. Though, having larger error bars certainly lowers the confidence of said result. I just thought it was cool that a novel technique which, and despite it having large margins of error, is still consistent (at least broadly speaking that is) with the consensus that the ocean is warming rapidly right now.
  14. Hmm...something may have gotten lost in translation. The mistake is probably on my end for not articulating the point very well or perhaps using the word "real" when I should have used a more appropriate term like "ultimate". At any rate this is not at all what I meant. And I'm not for a minute confusing the coined term "peer review" which is the step of vetting research prior to publication. My point is that reviewing research for correctness doesn't end once it's published. The ultimate review happens after publication when everyone gets to weigh in; not just a select few. The mistake that slipped through the cracks here isn't proof that the broader process is fundamentally flawed. Should the mistake have been caught by the peer review process prior to publication? Absolutely. Does this mean we should stop trusting the process? Nope.
  15. Yeah, I mean claiming that the IPCC underestimated ocean warming by 60% is a pretty extraordinary claim especially considering that the ocean's account for 90% of the warming. 60% of 90% is a huge discrepancy considering the consensus on the total heat uptake by the planet is confined to a pretty narrow range of possible values already. Typically when you have a result that is an extreme outlier like this you make every attempt to eliminate any possible mistake on your part first. This is especially true when you have a new technique that you're trying out for the first time like was the case with this particular publication. Like Carl Sagan said, "extraordinary claims require extraordinary evidence". I'd also like to make the point that this isn't a failure of the scientific process in any way. Peer review is a layered process. The smoke test happens at publication time when a only a smaller number of reviewers weigh in. It's a good first step that works well to vet out egregious mistakes and fraud. But, it's not fool proof. The real peer review process happens after the research is formally published and made public to the broader scientific community. The fact that this mistake was caught within 7 days of publication is a testament to the effectiveness of the process and the consensus building steps. And of course, this particular mistake in no way refutes the abundance of evidence their clearly and decisively shows that the oceans are warming at an incredibly rapid pace. Finally, I commend the authors for finding a novel technique that has never been tried before for quantifying ocean warming. I hope they continue their research and refine and improve upon their method.
  16. Yeah. I agree. We try should to figure why this year's refreeze is more aggressive than in recent years. We should strive to figure out every little nuance of weather/climate no matter how detailed and trivial. I'm sure solar cycles play a role. I just don't know how much. As with most things related to the climate its rarely ever just one thing. It's usually the net effect of a lot of stuff that makes for the best discriminator of climate behavior. For example, although a solar min by itself might not have much of an impact if it is phased precisely with a particular ENSO, AMO, and/or PDO cycle then the effect is magnified. My naive assumption is that solar cycles should have a bigger impact in the summer than the winter due to the fact that the poles receive relatively little solar insolation in the winter to begin with. But, I've learned over the years that my naive assumptions can be dead wrong. In fact, it's not unreasonable to think the link between sea ice extents and solar cycles is more indirect owing to the fact that the upper atmosphere is far more sensitive to the cycles than the troposphere. And of course, there are likely inertial lags between the peaks of the solar cycles and the peaks of the responses in the various elements of the climate system. I wouldn't be surprised if solar cycles have the complete opposite effect of what you'd expect as well. Anyway, I did a quick google search and I found this very recent paper right away and it's not even behind a paywall...yay! I must confess...I haven't actually read it yet. I'll try to do that later today. https://www.nature.com/articles/s41598-018-22854-0 This study investigates the role of the eleven-year solar cycle on the Arctic climate during 1979–2016. It reveals that during those years, when the winter solar sunspot number (SSN) falls below 1.35 standard deviations (or mean value), the Arctic warming extends from the lower troposphere to high up in the upper stratosphere and vice versa when SSN is above. The warming in the atmospheric column reflects an easterly zonal wind anomaly consistent with warm air and positive geopotential height anomalies for years with minimum SSN and vice versa for the maximum. Despite the inherent limitations of statistical techniques, three different methods – Compositing, Multiple Linear Regression and Correlation – all point to a similar modulating influence of the sun on winter Arctic climate via the pathway of Arctic Oscillation. Presenting schematics, it discusses the mechanisms of how solar cycle variability influences the Arctic climate involving the stratospheric route. Compositing also detects an opposite solar signature on Eurasian snow-cover, which is a cooling during Minimum years, while warming in maximum. It is hypothesized that the reduction of ice in the Arctic and a growth in Eurasia, in recent winters, may in part, be a result of the current weaker solar cycle.
  17. Berkeley Earth came in at +0.88 for October. GISTEMP came in at +0.96. As a point of reference at the peak in Feb. 2016 these values were +1.25 and +1.34 respectively. Last October was +0.77 and +0.88. So it has warmed about +0.10 since this time last year.
  18. Assuming extent gains increase by the 1981-2010 rate November will end with a mean of about 9.9e6 km^2. Then if we assume extents jump up and exactly match the 1981-2010 average (unlikely IMHO) then December will end with a mean of 12.8e6 km^2. This puts the final tally for 2018 at at mean 10.41e6 km^2. It would still be the 5th lowest annual mean just barely behind 2012 at 10.406e6 and 2017 at 10.393e6. Note that the top 5 would all be 2012 and later. So although the fast refreeze is interesting in it's own right it needs to be considered in context here. Unless someone has a convincing argument it's premature to think this is the start of a new era where sea ice extents begin a long term secular increase especially considering that we have a mountain of evidence that suggests sea ice extents will stagnate at best through the 2030's or just continue to decline.
  19. It does seem like there has been an extended run of generally quiescent weather in the midwest the last few years.
  20. SR15: http://www.ipcc.ch/report/sr15/ The focus was mainly on the 1.5C warming target.
  21. Even assuming higher freeze rates than have occurred recently persist for the remainder of the year then 2018 will still end with an annual mean < 10.5e6 km^2. That would be 4 years in a row now. To put this in perspective the IPCC AR3 report from 2001 suggested that the first occurrence of < 10.5e6 km^2 might not happen until 2040. Well it actually happened in 2007 about 33 years ahead of computer simulations available at the time. And yet we're about to experience 4 in a row of this happening well ahead of the expected first occurence. Furthermore they say "The simulations of ice extent decline over the past 30 years are in good agreement with the observations, lending confidence to the subsequent projections which show a substantial decrease of Arctic sea-ice cover leading to roughly 20% reduction in annual mean Arctic sea-ice extent by the year 2050." Note that a 20% reduction of the annual mean is about ~10.0e6 km^2. I just don't see how it's possible that we can make it to 2050 before the annual mean drops below 10.0e6 km^2. My point is two-fold. First, it's winter. The refreeze is expected. Just because it's happening faster now relative to recent years in no way means the longterm decline has suddenly reversed. And second, the expectation for the longterm decline has been severely underestimated by the IPCC at least in their earlier publications. So you'll have to forgive me for being skeptical that we'll also make past 2050 before the Arctic goes ice-free (defined as < 1.0e6 km^2) at least once in the summer. Sure, we might make it that long, but I'm not going to hold my breath.
  22. There may have been a miscommunication here. The consensus prediction on ice-free Arctic summers has not been delayed. It has actually been expedited. Earlier estimates from the 1990's were 2100 or even later. The IPCC has refined these predictions to be sooner; not later. Many scientists still think the IPCC is underestimating the melt out. Unfortunately, I can't fix the problem of the media (mainly from non-expert bloggers) misrepresenting, exaggerating, or misleading their audience regarding the science of climate change. The best option for those who are serious about learning about climate change or have a vested interest in it should ignore the media and instead listen to what the scientific consensus says. The IPCC publications are actually a pretty good proxy for the consensus IMHO.
  23. Sure there are aggressive predictions of sea ice loss (Maslowski for example), but these are generally ignored by the majority of experts. They have not been incorporated by the consensus. The consensus prediction is currently sitting at around 2050'ish which has actually come down some from the 1990's. So far the consensus has generally underestimated the decline so 2050 may not be aggressive enough. It'll be interesting to see what the IPCC says when AR6 is released in a couple of years. As a general rule you can find onesie-twosie lines of evidence to support just about any prediction no matter how absurd. That doesn't mean that we should take them seriously or that they should automatically get incorporated into and as the consensus prediction. That's a good thing because if we just blindly accepted every line of evidence we came across then we'd be forced into the awkward and contradictory position of believing that an ice-age and a Permian-like hothouse Earth are both imminent.
  24. Can you clarify the difference between EDEX Service Access and EDEX Priority access? Also, for those that don't know AWIPS is actually a pretty useful tool. There is a Windows version now which I haven't played around with yet. But I can tell you that AWIPS installs quite nicely in a CentOS 7 instance running inside VMWare. You just need to have "enable 3D graphics" ticked in the VMWare settings.
  25. So if I'm reading this right the quasi resonant amplification events can be expected to increase at a relatively slow rate in a regime where aerosol emissions decline and are slowly depleted from the atmosphere. This creates an effect opposite of Arctic amplification because more solar radiation is able to penetrate in the mid latitudes (where aerosols have typically had the highest densities in the past) causing them to warm faster than the Arctic region. Once aerosols are fully depleted, however, we return back to the greenhouse gas dominated regime of Arctic amplification. It's the Arctic amplification that causes the polar jet to slow down thus allowing it to wander down lower in latitude while simultaneously getting "wavier". Note that the research cited doesn't say the QRA event recurrence intervals will stablize (in the short term anyway) because the warming is slowing down. What they are saying is that they expect the warming to be more homogeneous in the coming decades thus suppressing the growth rate of QRA event frequencies at least until aerosols have been fully depleted.
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