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Snow_Miser

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Everything posted by Snow_Miser

  1. Didn't know you were a skeptic too at one point. I accepted the mainstream conclusions of the science, when it became abundantly clear that we were still warming, and there was no sign of any prospective cooling. Learning more about the subject didn't hurt either. It's been over 3 years since I recognized this. There are no energy accumulation lags. Zero. It is like saying that a pot on a stove will continue to gain energy, even after the burner has been turned off. It makes no physical sense. So the continued upper ocean heat accumulation is totally inconsistent with reduced solar activity. It is just not causing current climate change. Getting back on topic, a pretty poor pattern for the Pacific side of the ice is on the way. The 12z ECMWF is advertising well above normal 850 hPa temperatures in the medium range and beyond for that region. Kind of surprised we still saw sizable losses over the last few days, despite cooler than normal 850 hPa temperatures. Unless recent losses have all come from the Hudson Bay. I think persistence type predictions of the sea ice minimum, like June melt ponding have the potential to be more inaccurate than usual this year. With the ice being so thin, it won't take as much to see sizable losses in the coming couple of months.
  2. The higher thicknesses relative to normal are getting exported in the Fram, according to the May PIOMAS update. Across the Arctic Basin, lots of thinner than normal ice. From Zack Labe.
  3. Welcome back Friv. Not a pretty depiction by ensemble forecasts over the next 10 days for the Pacific side.
  4. Record low volume continued into March. It would be impressive at this point if September also did not see record low volume.
  5. Loss of -12K yesterday on NSIDC. With an unfavorable pattern for ice growth persisting, I don't expect significant ice growth for at least another couple days.
  6. As was mentioned by csnavywx, anomalous warmth looks to return to the Kara Sea (and much of the Arctic), alongside a low approaching ~960 hPa. Not only is this a favorable pattern for Fram export of whatever multiyear ice remains, but temperatures will run close to 30 degrees Celsius above normal once again for portions of the Arctic.
  7. NSIDC has now dipped below 2007's minimum, making this year the 2nd lowest minimum on record.
  8. Awesome talk by Dr. Richard Alley at the annual 2015 Penn State Chi Epsilon Pi spring buffet. Talked about how the geologic record showed Carbon Dioxide as a significant causal agent of warming and the non significant aspect of cosmic rays on the climate.
  9. It's comments like this that deter people from a skeptical position on this issue.
  10. The climate isn't as sensitive to small solar variations like the 11 year cycle as it is to long term solar variations, like the De Vries cycle. Longer term solar variations on a decadal to centennial scale have about a 50-70 year temperature response lag, and have more noticeable impacts on the climate. The reasoning, according to Zanchettin et al. is: "Although most of the Sun-climate mechanisms are not well understood yet, a host of empirical evidence suggests that solar energy changes alter the Earth’s climate significantly [Eddy, 1976; Haigh, 1996; Shindell et al., 1999; Marsh and Svensmark, 2003; Lambert et al., 2004; Georgieva et al., 2005] and that climate sensitivity to solar variations obeys a frequency-dependent transfer function of solar energy, so that the damping effect of the oceanic and atmospheric thermal inertia make the climate more sensitive to slower solar variations [Wigley, 1988; Foukal et al., 2004; Scafetta and West, 2006]." From Helama et al. 2010.
  11. You can see some pretty unscientific comments on both sides in this video. http://www.youtube.com/watch?v=y34R7hSpEb0
  12. Pretty sure the differences between a lot of those years are not even close to being statistically significant. The yellow line isn't a linear trend, but it's a reference point.
  13. There's stupid for #6 and #1. I've discussed with people that believed the anthropogenic forcing was a hoax or that CO2 actually cooled the atmosphere. Or that Global Warming was an evil plot to get more regulation. There's also people who want to attribute everything to Global Warming, who look equally ridiculous.
  14. Making statements like the "science is settled" implies that we know everything about an issue. That's obviously not true, as you yourself have stated. Yes, Global Warming has occurred, but what extent of it is anthropogenic? How much will we warm in the future? How much has this warming impacted weather? These are all viable questions.
  15. You can find dozens of examples of scientists and non-scientists claiming the science is settled and that the debate is over. It's a ridiculous attempt at suppressing the skeptical view.
  16. Pinker et al. found a 0.16 w/m^2/year increase in incoming insolation during the late-20th Century though.. that would be equivalent to 1.6 w/m^2/decade and that would also be comparable to the value found in the Herman et al. study. Again.. this doesn't represent a forcing.. because the longwave cooling still needs to be taken into consideration.
  17. Keep in mind that this doesn't represent a radiative forcing, since as the paper notes, this value is partially offset by increased longwave radiation being allowed to radiate to the TOA, due to the decreased Cloud Cover. Even if we assume that 50% of the net SW absorbed (2.3 w/m^2) is cancelled out by the longwave cooling, then that is still fairly substantial, and represents a 1.2 w/m^2 forcing. Again, this is just hypothetical. I'm not sure how much the increased longwave cooling associated with decreased Cloud Cover would offset the increased shortwave radiation being absorbed at the surface, and the paper's abstract did not specify. I remember seeing that the IPCC estimated the net anthropogenic radiative forcing during the late-20th Century to be somewhere around 0.9 w/m^2, so thus, assuming that all of the late-20th Century warming was forced, and natural variability didn't play any role (which is unlikely) you can get a sensitivity that is pretty low.. around 1 Degree C. This is all assuming that the study's findings are correct. There are other studies like Pinker et al. that show Global Brightening over the late-20th Century.. though I'm not sure what the magnitude of the increase is compared to this study's.
  18. Again, recent satellite measurements indicate that the trend has reversed and an increase in SW Radiation has been absorbed at Earth's surface over the last 30-35 years. This would suggest less "masking" of the warming since there is more SW Radiation being absorbed at the end of the late-20th Century than in the mid-20th Century, representing a radiative forcing. Other studies found that the decrease in Cloudiness is unrelated to anthropogenic aerosols. http://www.ann-geophys.net/30/573/2012/angeo-30-573-2012.pdf "Frequencies of clear sky (cloud cover <20%) and overcast days (cloud cover >80%) were observed to increase by ~2.2 days and decrease by ~3.3 days per decade, respectively, which accounts for ~80% of cloud cover reduction. Larger decreasing trends in cloud cover due to larger increase in clear sky frequency and larger decreases in overcast frequency were observed at stations with lower aerosol optical depth. There is no significant difference in trends regarding cloud cover, clear sky frequency, and overcast frequency between mountain and plain stations. These results are inconsistent with our expectation that larger decreasing trends in cloud cover should have been observed in regions with higher aerosol loading where more aerosols could lead to stronger obscuring effect on ground observation of cloud cover and stronger radiative effect as compared with the mildly polluted regions. Aerosol effect on decreasing cloud cover in China appear not to be supported by this analysis and therefore, further study on this issue is required." Regional warming also correlates to multidecadal variations in the amount of SW radiation being absorbed, as well as to TSI changes, suggesting that some of the variability in the SW changes is due to natural factors, as well as human factors. http://www.sciencedirect.com/science/article/pii/S1364682611002161
  19. To back up your point: You can see how far off the models simulated the observed trends in Dec-Feb especially in recent years. http://klimazwiebel.blogspot.com/2013/09/the-intriguing-stagnation.html
  20. I linked you to one of your previous posts suggesting the accepted sensitivity to be 3 Degrees C with a lower bound of 2 Degrees C. The models, which have a ECS of 3.2 Degrees C do generally simulate too much cooling when compared to observations during cooling events like Mt. Pinatubo. In addition, the models underestimate the early-20th Century temperature trend, which suggests they are too sensitive to changes in radiative forcing. In addition, in the GCMs, with just changes in Water Vapor, Lapse Rate, and Surface Albedo only produce an ECS of 1.9 Degrees C. This means that if the Cloud Feedback is negative, ECS can easily be lower than 2 Degrees C. A lot of recent studies, as I've said have gradually been shifting away from the 2-4.5 Degree C figure. Quite a few have high probability densities between 1-2 Degrees C, with some even lower than that.
  21. Part of the Global Brightening trend since 1979 may also have to with the +PDO. There was some rough speculation by Roy Spencer that the mechanism for which the PDO can cause warming on multidecadal timeframes is through a decrease in Cloud Cover.
  22. That's interesting. Only a few months ago, you were saying that the accepted climate sensitivity was 2-4.5 Degrees C, and that anyone who would dare put out sensitivity values lower than 2 Degrees C were, according to your definition, a biased ignoramus. Unfortunately for your definition, there are actually a lot of recent peer reviewed studies focusing on sensitivity values between 1-2 Degrees C. Skeie et al. is one of the most recent examples. Ring et al. and Asten are also recent examples as well, finding sensitivities of 1.77 Degrees C and 1.1 Degrees C respectively. Now you say that the accepted values is now 1.5-4.5 Degrees C, which I guess had to do with the latest IPCC report lowering the lower bound of the sensitivity from 2 to 1.5 Degrees C, which is a nod to the with many recent studies finding an ECS of 1-2 Degrees C.
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