bdgwx Posted November 30, 2018 Share Posted November 30, 2018 On 11/29/2018 at 8:43 PM, BillT said: "all other things being equal" that sum up the POINT for me all things are NOT ever equal so your sides entire position is based on NON existent NON reality.......YOUR side is assigning a power to co2 that it simply does NOT have. 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. Link to comment Share on other sites More sharing options...
bdgwx Posted November 30, 2018 Share Posted November 30, 2018 12 hours ago, Save the itchy algae! said: The sun has far more power on our planet than CO2, it borders on ridiculous to suggest otherwise. That study is not powered well, and I'm pretty sure that institution has been known to push agendas for funding purposes in the past. The only thing that has a remotely higher impact on us than the sun are things like drastic changes in oceanic composition and planetary events like super volcanoes and meteors. I don't mean to come across too critical, you just seem too set in your ways. 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. Link to comment Share on other sites More sharing options...
bluewave Posted November 30, 2018 Share Posted November 30, 2018 1 Link to comment Share on other sites More sharing options...
Fantom X Posted November 30, 2018 Share Posted November 30, 2018 18 hours ago, bdgwx said: 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. Professor Valentina Zharkova recently gave a presentation and suggested at the worst of the GSM, the forcing loss could be as low as - 8.0 W/m2. Link to comment Share on other sites More sharing options...
bdgwx Posted November 30, 2018 Share Posted November 30, 2018 38 minutes ago, Fantom X said: Professor Valentina Zharkova recently gave a presentation and suggested at the worst of the GSM, the forcing loss could be as low as - 8.0 W/m2. 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. 1 Link to comment Share on other sites More sharing options...
bdgwx Posted December 3, 2018 Share Posted December 3, 2018 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. Link to comment Share on other sites More sharing options...
forkyfork Posted December 19, 2018 Share Posted December 19, 2018 what happened to snowlover? Link to comment Share on other sites More sharing options...
bdgwx Posted December 19, 2018 Share Posted December 19, 2018 I looked at the data this morning. Assuming I didn't miscalculate at the current pace 2018 is on track to have the 2nd lowest annual mean sea ice extent. The top 3 lowest would be 2016, 2018, and 2017. Link to comment Share on other sites More sharing options...
chubbs Posted December 21, 2018 Share Posted December 21, 2018 November Antarctic sea ice. Blutarsky. 1 Link to comment Share on other sites More sharing options...
bdgwx Posted December 21, 2018 Share Posted December 21, 2018 And combined SH and NH sea ice extents are now 2nd lowest. And aside from a couple of brief blips global sea ice has remained below 2σ from the mean for about 2.5 years now. And much of that time it was actually 3σ below the mean. 1 Link to comment Share on other sites More sharing options...
csnavywx Posted January 1, 2019 Share Posted January 1, 2019 The Antarctic season has been remarkably bad and is now dead last in both extent and by a large margin in area. It's also in considerably worse shape (concentration wise) than even 2016. 1 Link to comment Share on other sites More sharing options...
WidreMann Posted January 3, 2019 Share Posted January 3, 2019 On 1/1/2019 at 12:15 PM, csnavywx said: The Antarctic season has been remarkably bad and is now dead last in both extent and by a large margin in area. It's also in considerably worse shape (concentration wise) than even 2016. I don't follow SH weather patterns. What do you think is the cause? Link to comment Share on other sites More sharing options...
csnavywx Posted January 3, 2019 Share Posted January 3, 2019 14 hours ago, WidreMann said: I don't follow SH weather patterns. What do you think is the cause? Warmer temps, less clouds and unfavorable winds. The last 3 years have been pretty bad, but this one takes the cake with all of the early ponding and breakup. Link to comment Share on other sites More sharing options...
bdgwx Posted January 3, 2019 Share Posted January 3, 2019 Preliminary numbers show that the annual mean extents for the NH finished second lowest behind 2016. SH was similar...it finished second lowest behind 2017. The SH is whole different beast, but the fact that we had 2018 end badly lends a bit of credence to the idea that 2017 may not have a fluke. I wonder if we're beginning to observe the paradigm shift down there too. Any thoughts csnavy? Link to comment Share on other sites More sharing options...
bluewave Posted January 3, 2019 Share Posted January 3, 2019 1 hour ago, bdgwx said: Preliminary numbers show that the annual mean extents for the NH finished second lowest behind 2016. SH was similar...it finished second lowest behind 2017. The SH is whole different beast, but the fact that we had 2018 end badly lends a bit of credence to the idea that 2017 may not have a fluke. I wonder if we're beginning to observe the paradigm shift down there too. Any thoughts csnavy? It could be the trapped heat finally reaching the surface. https://www.carbonbrief.org/natural-ocean-fluctuations-help-explain-antarctic-sea-ice-changes/amp?__twitter_impression=true There’s clearly an ocean component to this story, which this study seems to clarify. Assuming this theory is correct, we might expect to see a decrease in sea ice cover in coming years, as, eventually, enough heat builds up that it has to come to the surface and melt ice – combined with the impacts of human emissions.” It is possible that this could explain why, during 2016, sea ice levels reached record lows, he adds: “It’s intriguing to wonder whether this is what happened in 2016 when Antarctic sea ice suddenly dropped to record lows, but more work would be needed to state whether that was actually the case, or just due to an atmospheric anomaly.” Although the overall magnitude of changes to ocean convection is not yet known, it is possible that the trapped heat could escape to the surface, Zhang says: “The trapped heat can reach the sea surface and melt sea ice once the subsurface heat has accumulated to a strong enough degree.” Link to comment Share on other sites More sharing options...
csnavywx Posted January 3, 2019 Share Posted January 3, 2019 3 hours ago, bdgwx said: Preliminary numbers show that the annual mean extents for the NH finished second lowest behind 2016. SH was similar...it finished second lowest behind 2017. The SH is whole different beast, but the fact that we had 2018 end badly lends a bit of credence to the idea that 2017 may not have a fluke. I wonder if we're beginning to observe the paradigm shift down there too. Any thoughts csnavy? It's possible we've turned the corner down in the SH, but it's hard to say with only 3 years. Some of the bad conditions this year are undoubtedly just weather. However, the reappearance of stronger deep convection (for example, -- Weddell Sea polynya -- after decades of absence) could mean that we're returning to a circulation regime less conducive to retaining sea ice in the melt season. A great deal of heat burial has taken place in the Southern Ocean over the past 20-30 years, so any relaxation of that pattern will of course allow some of that to resurface and augment the background GHG forcing. Interestingly, this heat burial mechanism is occurring under the Arctic as well via transport from the Pacific through the Bering and under the Chukchi Sea into the CAB. It is also coming from the Atlantic via the Barents (where the intermediate warm layer has intensified rapidly and shoaled over time). Once that reaches critical mass (10-15 years), it too will surface and bite into the CAB. Link to comment Share on other sites More sharing options...
etudiant Posted January 3, 2019 Share Posted January 3, 2019 What is 'heat burial'? I'd been under the impression that while polar waters were slightly below 0*C, deep ocean water was around 4*C, with the temperature falling as the depth increases in temperate/tropical waters. Am I off base? Is there some paper that would help lay out the process in more detail? Link to comment Share on other sites More sharing options...
csnavywx Posted January 4, 2019 Share Posted January 4, 2019 Diffusion of heat down the water column via mixing or and/or subduction under a vertical salinity gradient. Stronger winds will increase the depth of the mixed layer, bringing up colder intermediate and (in some cases) deep water to mix with near-surface waters, for instance. When combined with increased heat uptake due to GHG (and other) forcing, that causes said heat to be "buried" at depth, even though surface waters may cool. This can give the illusion that the extra heat is gone, but in reality, it has simply been mixed or subducted down. The situation can change if the circulation state (via natural variability or otherwise) changes, allowing some of that heat to effectively resurface. Link to comment Share on other sites More sharing options...
etudiant Posted January 5, 2019 Share Posted January 5, 2019 31 minutes ago, csnavywx said: Diffusion of heat down the water column via mixing or and/or subduction under a vertical salinity gradient. Stronger winds will increase the depth of the mixed layer, bringing up colder intermediate and (in some cases) deep water to mix with near-surface waters, for instance. When combined with increased heat uptake due to GHG (and other) forcing, that causes said heat to be "buried" at depth, even though surface waters may cool. This can give the illusion that the extra heat is gone, but in reality, it has simply been mixed or subducted down. The situation can change if the circulation state (via natural variability or otherwise) changes, allowing some of that heat to effectively resurface. The subduction you explain makes perfect sense. It is the heat surfacing that is puzzling. Will not the water coming up from below still be somewhat colder than the surface water it displaces? So even if it is warmer than it was without the GHG effect, it would still continue to take up heat, only at a lesser rate. Is this a reasonable description of the expected effect? Link to comment Share on other sites More sharing options...
snowlover91 Posted January 24, 2019 Share Posted January 24, 2019 Since PIOMAS is unavailable due to the govt shutdown, here is the latest DMI volume. Antarctic ice loss is slowing down after a rapid drop. It appears the remaining ice is mainly high concentration ice so the loss should level out fairly soon. 1 Link to comment Share on other sites More sharing options...
chubbs Posted January 28, 2019 Share Posted January 28, 2019 Rapidly receding Arctic Canada glaciers revealing landscapes continuously ice-covered for more than 40,000 years Here we show that pre-Holocene radiocarbon dates on plants collected at the margins of 30 ice caps in Arctic Canada suggest those locations were continuously ice covered for > 40 kyr, but are now ice-free. We use in situ 14C inventories in rocks from nine locations to explore the possibility of brief exposure during the warm early Holocene. Modeling the evolution of in situ 14C confirms that Holocene exposure is unlikely at all but one of the sites. Viewed in the context of temperature records from Greenland ice cores, our results suggest that summer warmth of the past century exceeds now any century in ~115,000 years. https://www.nature.com/articles/s41467-019-08307-w Link to comment Share on other sites More sharing options...
bluewave Posted February 5, 2019 Share Posted February 5, 2019 https://mobile.twitter.com/ZLabe/status/1092449357096353792 2018's average #Arctic sea ice extent was the 2nd lowest on record Data from consistent passive microwave satellite record (1979-2019) Link to comment Share on other sites More sharing options...
nycwinter Posted February 5, 2019 Share Posted February 5, 2019 On 1/27/2019 at 7:22 PM, chubbs said: Rapidly receding Arctic Canada glaciers revealing landscapes continuously ice-covered for more than 40,000 years Here we show that pre-Holocene radiocarbon dates on plants collected at the margins of 30 ice caps in Arctic Canada suggest those locations were continuously ice covered for > 40 kyr, but are now ice-free. We use in situ 14C inventories in rocks from nine locations to explore the possibility of brief exposure during the warm early Holocene. Modeling the evolution of in situ 14C confirms that Holocene exposure is unlikely at all but one of the sites. Viewed in the context of temperature records from Greenland ice cores, our results suggest that summer warmth of the past century exceeds now any century in ~115,000 years. https://www.nature.com/articles/s41467-019-08307-w Warmth. Around 130,000-110,000 years ago (the Eemian interglacial), the Earth's climates were generally much like those of today, though somewhat warmer and moister in many regions. The climate record derived from long ice cores taken through the Greenland ice cap suggested that the warm climate of the Eemian might have been punctuated by many sudden and fairly short-lived cold phases, but these results are now thought of as inaccurate because the lower layers of the ice sheet have become buckled and jumbled up. However, at least one major cold and dry event during the Eemian seems to be corroborated by the terrestrial pollen record from Europe and China Link to comment Share on other sites More sharing options...
bluewave Posted February 10, 2019 Share Posted February 10, 2019 https://mobile.twitter.com/ajatnuvuk/status/1093786714022105088 It’s February, the coldest month of the year. We have open water in front of Utqiagvik. It is 30 F out at 11:20 at night. Strange days indeed. https://mobile.twitter.com/AlaskaWx/status/1094296276730925056 Incredible warmth on the North Slope Friday, with temperatures in most places 30 to 50F (18-28C) above the daily normal! https://mobile.twitter.com/AlaskaWx/status/1094017492580655105 MODIS image from Friday afternoon courtesy @uafgina showing impacts on #seaice in the northern Bering & southern Chukchi Seas of recent mild, stormy weather. A lot of water showing up, even significant areas north of the Bering Strait. 1 Link to comment Share on other sites More sharing options...
bdgwx Posted February 13, 2019 Share Posted February 13, 2019 This is a thread focused on the Arctic region, but it's the Antarctic behavior that's most striking. There was a transition from record highs in 2013, 2014, and 2015 to record lows in 2016, 2017, and 2018. It almost seems like a fluke. I'm wondering if we won't see a reversion to the mean in the next few years. In looking at the IPCC predictions from model simulations there was an expectation that Antarctic sea ice extents would hold steady and perhaps even increase ever so slightly through 2025. Arctic sea ice is behaving about as expected. I realize the IPCC has underestimated the magnitude of the decline, but at least the general trend (downward) has been correct. The trend could even tolerate a sizable jump at this point perhaps even up to 2008/2013 levels. Link to comment Share on other sites More sharing options...
chubbs Posted February 14, 2019 Share Posted February 14, 2019 On 2/12/2019 at 11:58 PM, bdgwx said: This is a thread focused on the Arctic region, but it's the Antarctic behavior that's most striking. There was a transition from record highs in 2013, 2014, and 2015 to record lows in 2016, 2017, and 2018. It almost seems like a fluke. I'm wondering if we won't see a reversion to the mean in the next few years. In looking at the IPCC predictions from model simulations there was an expectation that Antarctic sea ice extents would hold steady and perhaps even increase ever so slightly through 2025. Arctic sea ice is behaving about as expected. I realize the IPCC has underestimated the magnitude of the decline, but at least the general trend (downward) has been correct. The trend could even tolerate a sizable jump at this point perhaps even up to 2008/2013 levels. Antarctic sea ice has large natural variability. Here are a couple of speculations: 1) I don't recall the details but one paper flagged the the large nino in 2015/16. For sea ice the timing does line-up, 2) The antarctic ozone hole is slowly recovering this would tend to weaken winds and produce warming, both of which will reduce sea ice extent 3) Antarctica warming lags because of the deep ocean nearby which is slow to warm. as time proceeds though Antarctica will catch-up. Per the chart below, the south pole has also warmed in the past decade in a way that doesn't match enso, so it is likely more than just enso. Link to comment Share on other sites More sharing options...
bluewave Posted February 25, 2019 Share Posted February 25, 2019 https://mobile.twitter.com/AlaskaWx/status/1099865227414331393 330pm AKST Sunday SNPP shows more of Kotzebue Sound. Ice completely pulled away from northern Seward Pen coast. Southern Chukchi Sea looks like more like late May/early June. Suomi NPP image 147pm AKST Sunday shows the weekend storm has decimated #seaice in the Bering Sea. Little more than "junk ice" anywhere in the open Bering Sea except near the Strait. Impacts on communities and ecosystems continue apace. Utqiaġvik (Barrow) high temp so far today 30F (-1.1C) is a new record high for February 24rd. Previous record 29F (-1.8C) in 2011 & fifth day this month to set or tie a daily record high. Climate obs since October 1920. # Link to comment Share on other sites More sharing options...
raindancewx Posted February 26, 2019 Share Posted February 26, 2019 The ice extent on the Atlantic side must be pretty high given the warmth in Alaska? Since the late February extent numbers are above 2018, 2017, 2016, 2015, 2014, 2011, 2007, 2006 and 2005. If that's the case it does kind of make sense, the AMO has been pretty cold recently. Link to comment Share on other sites More sharing options...
bluewave Posted February 28, 2019 Share Posted February 28, 2019 https://mobile.twitter.com/AlaskaWx/status/1101160230199603200?ref_src=twsrc^google|twcamp^serp|twgr^tweet Very little #seaice left in Alaskan waters of the Bering Sea from AMSR2 data as continued storminess has eroded away near all of the ice south of 64N. The significant areas of open water in the southern Chukchi Sea and Kotzebue Sound just stunning. https://mobile.twitter.com/AlaskaWx/status/1101263457918234629?ref_src=twsrc^google|twcamp^serp|twgr^tweet Suomi NPP image courtesy @uafgina early Thursday afternoon, February 28. The loss of #seaice in the Bering and southern Chukchi Seas is beyond belief. The impacts to western Alaskan communities immense. https://mobile.twitter.com/AlaskaWx/status/1101300151388332032?ref_src=twsrc^google|twcamp^serp|twgr^tweet Utqiaġvik (Barrow) sets a new record high temperature for February 28. Through 3pm AKST, the high has been 33F (+0.6C), which nips the previous record of 32F (0.0C) set in 1960. This is the 6th day this month to set or tie a daily record high. Link to comment Share on other sites More sharing options...
chubbs Posted March 5, 2019 Share Posted March 5, 2019 IPO phase could bring September ice-free date forward. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018GL081393 Link to comment Share on other sites More sharing options...
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