Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  1035  1036  1037  1038  1039  1040  1041  1042  1043  1044  1045  1046  1047  1048  1049  1050  Next

Comments 52101 to 52150:

  1. Climate of Doubt Strategy #1: Deny the Consensus
    Sensenbrenner's remarks about "scientists and their supporters" make me wonder if he'd need to be persuaded to use a ladder to climb down from a roof rather than simply jump. On the one hand "physicists and their supporters" say Sensenbrenner would risk being hurt by jumping 20' to the ground but on the other hand who can really say? It's controversial; after all, gravitation is only a theory and doubtless some crazy people can be found who think our confinement to Earth is just mass hysteria. Why not leap off the roof and let events prove the truth? Not likely Sensenbrenner would jump from a roof but he's prepared to impose bigger risks on himself and many others. Odd.
  2. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    Indeed Uncle Pete. And not to forget the real estate industry's liaisons with the likes of David Archibald, Ian Plimer, and Bob Carter.
  3. Hansen predicted the West Side Highway would be underwater
    Photo of flooding along the Westside Highway during Hurricane Sandy.
  4. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    @Bernard J . Never underestimate the power of the real estate industry and their close liaisons with politicians.
  5. Climate of Doubt Strategy #1: Deny the Consensus
    Thanks for another great post. I sometimes wonder how these people can sleep with a clear conscience. Then again, the laws of physics even apply to the universe these thinktankers inhabit. I suppose Sandy is a just an appetiser of what is in store for the biosphere.
  6. Postma disproved the greenhouse effect
    Yes, Doug: I've seen your "new science" before. Isn't that Sonja Boehmer-Christiansen I hear calling your name?
  7. Climate of Doubt Strategy #1: Deny the Consensus
    We Need to Communicate the Consensus to the Public
    I've said it before and I'll say it again: professional scientific organisations need to be deliberately and conspicuously standing squarely in the limelight to strenuously inform the public that the issue of human-caused planetary warming is Real, that it is Serious, and that it is Now. If politics won't stay out of science, then science needs to wedge a foot in the door of the political strategy rooms and straighten the record. And kudos for the Skeptical Science team, for their invaluable and world-leading efforts in this regard.
  8. Postma disproved the greenhouse effect
    Postma's new paper. There's nothing new about it. Some of it is downright tedious. 3.4. The back-radiation/glass greenhouse justification for the GHE Please see Appendix H for a sample list of quotation references adhering to the backradiation mechanism of the GHE. All the references and quotations therein conform to the “backradiation model” of the GHE, which is based on a comparison with actual greenhouses made of glass. The problem is that this well-known comparison is incorrect. Go and have a look if you're interested, but don't expect anything new, or even interesting.
  9. Climate of Doubt and Escalator Updates
    You go to a gas station to fill up on hydrocarbon fuel which powers an engine designed to eficiently burn the hydrocarbon fuel with pure oxygen. The hydrogen combines with oxygen to produce heat and H2O. The carbon combines with oxygen to produce heat and CO2. The temperatures attainable are higher than using air, which contains 79% Nitrogen. The efficiency of a heat to work engine is proportional to the difference between the highest and lowest cycle temperatures (Carnot). The products are work, CO2 and water. The CO2 can be temporarily captued in a recyclable media, which is recycled at the gas station while you fill up. Zero emissions, much better gas mileage, higher efficiency, unbelievable power.
    I'd like to see the energy budget that accounts for: 1) the costs of purifying, storing and delivering the O2, 2) the costs of collecting, storing and safely and permanently disposing of the CO2 and, as others have pointed out, 3) for the vehicle retooling that would be necessary. How do these thermodynamically-unavoidable costs compare with the increased combustion efficiently returned from using pure oxygen?
  10. Climate of Doubt Strategy #1: Deny the Consensus
    Another solid effort addressing the communication front in this battle over reality. A spin that is often used and one that serves as an anchor for the "deskepticons" to turn the tables on consensus is this "97% consensus" statement. I respectfully disagree with your suggestion that we drive this number home and as an alternitive suggest a more detailed set of numbers while completely avoiding this simple percentage...allow me to explain. The issue of consensus is done a disservice by any mention of this oft repeated percentage as its use quickly opens the door to the statistically insignificant sample size that was used to gives us the "97%"; discount the sample size and you discount the percentage in the finding, discount the finding and you discount the consensus. Discount the consensus and you call into to question a variety of empirical metrics with any outlier that offers a contrarian conclusion. The baby steps of denial. Rather than make any mention of the 97% I suggest the following mash up of Dana's statement: -A 2004 survey of 928 peer-reviewed climate science abstracts, found 75% either explicitly or implicitly endorsed the consensus view, while finding no papers rejecting and later in 2009, a review of 1,372 climate researchers and their publication and citation data showed a 97–98% of the researchers most actively publishing in the field support the tenets of human induced climate change.- The "97% consensus" statement is so overloaded with caveat that it really only serves as a softball to be driven deep into the denial-a-sphere by "deskepticons" and his Lordship. Break away from the simple reference and add the structure of significance that the details present. "the climate denial movement knows they don't need to win the scientific argument as long as they can convince the public that there is an ongoing scientific debate regarding climate change." It's never about the truth, just the perception. I would't doubt it if someone told me there is a plaque hanging in the Heartland conference room that says: "It's their perception stupid"
  11. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    DMCarey, I think you misinterpreted YubeDude. I thought he made a point that we get frustrated with the icers. Granted, he might be a Republican but does that really matter here? I have heard reports that people right in the path are not even doing the basics to survive a power outage for a few days. Lack of personal responsibility in a modest planning mode could save a lot of lives, but most people really do expect the government services to 'save' them.
  12. Climate of Doubt Strategy #1: Deny the Consensus
    Did you mean denyers - or delayers? :-) However, the formula for climate delayers is a simple one Great article by the way...
  13. Climate of Doubt and Escalator Updates
    "Exactly". Something that takes a complete redesign of the car is not a stopgap measure - it would take 25years to replace vehicle fleet with new technology. We would be better off doing that transition to electric rather than a pure O2 fossil fuel burner. For a pure O2 burner to get more kms per litre of fossil fuel, it needs to be a lot better at converting chemical energy to kinetic and as a result must exhaust much less heat. At first glance, it is hard to see how pure O2 makes that difference. You have either carry heavy O2 tank on car as well as fuel, or carry an O2-stripping apparatus in the car as well. Pure o2 should result in more power so perhaps a smaller engine but an internal combustion engine is going to have major fun with the temperature. I'm skeptical - electric seems better to me - but I'm open to be convinced by actual designs.
  14. Climate of Doubt and Escalator Updates
    I seem to remember a (apocryphal?) story about a car or truck accidentally being run through a wall into an area at Cape Kennedy where the air was enriched w/oxygen for some reason. If I remember rightly the main the outcome was lots of flame in the wrong places; impromptu external combustion engine, so to speak. Can't find the story on Google so presumably it does not even rise to the level of Internet rubbish...
  15. Climate of Doubt and Escalator Updates
    scaddenp, EXACTLY!!
  16. Climate of Doubt and Escalator Updates
    sincam - i think if pushed pure oxygen in the engine, you would loose the engine very quickly and very messily. You would need a complete redesign to use pure O2.
  17. Climate of Doubt Shines a Light on the Climate Denial Movement
    Also Bill. If you are only looking at surface temperature stations, then note that models (in which the heating is continuous) can show quite long periods of flat surface temperatures. For a rather infamous example look at Keenlyside et al 2008 - fig 3 for instance.
  18. Climate of Doubt Shines a Light on the Climate Denial Movement
    See here for article on measuring the earth's energy imbalance. It has links to many of the relevant papers.
  19. funglestrumpet at 06:22 AM on 30 October 2012
    2012 SkS Weekly Digest #43
    On a lighter note, imagine debating climate change with the woman in this video
  20. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    YubeDude, that really is the kind of reply that makes you want to scream. I've seen several attempts at dismissing or manipulating Sandy, but that is the first where the cooling spin was attempted to be put on it. Earlier today I had the... luxury... of listening through a taxing explination that the fuss over Sandy has been hyped up by the "leftist media" in order to swing voters for Obama. The really frustrating part is I'm in Canada, and still in the path of the hurricane at that. To see the potential damage the US might undergo as a result of Sandy brushed off as a political ploy is just infuriating
  21. Climate of Doubt and Escalator Updates
    vroomie. You go to a gas station to fill up on hydrocarbon fuel which powers an engine designed to eficiently burn the hydrocarbon fuel with pure oxygen. The hydrogen combines with oxygen to produce heat and H2O. The carbon combines with oxygen to produce heat and CO2. The temperatures attainable are higher than using air, which contains 79% Nitrogen. The efficiency of a heat to work engine is proportional to the difference between the highest and lowest cycle temperatures (Carnot). The products are work, CO2 and water. The CO2 can be temporarily captued in a recyclable media, which is recycled at the gas station while you fill up. Zero emissions, much better gas mileage, higher efficiency, unbelievable power.
  22. funglestrumpet at 03:30 AM on 30 October 2012
    2012 SkS Weekly Digest #43
    "When and how did you first become concerned about manmade climate change and its consequences?" I have yet to become concerned about manmade climate change. What I am concerned about, and extremely so, is climate change regardless of what the heck is causing it. I think anyone who watched the recent video 'Climate of Doubt' can't help but to have noticed how much the debate got hung up on the 'manmade' bit and just how effective it is in deflecting the debate from reducing the fossil fuel industry's profits – sorry – deflecting action to combat climate change. A scenario that I use (repeatedly) concerns the actions of the captain of a liner with an iceberg dead ahead. It would be an act of supreme folly to refuse to change course and reduce speed simply because the damn thing was not manmade. We know that CO2 is a greenhouse gas. We know that we are pumping CO2 into the atmosphere and therefore, even if it were the sun or some other natural phenomenon that is causing the warming, it would still make sense to cut CO2 production in order to offset the heating effect, whatever its cause, if only by a little. Indeed, if climate change were being caused by the sun, or some other natural phenomenon, I suppose we should all be praying, chanting and doing all that sort of thing because the warming would be destined to continue at or near the current rate until Old Mother Nature, and only Old Mother Nature, decided enough is enough, whenever that might be. In those circumstances all we could do is delay it a little by reducing CO2 (and pray and chant etc., of course). I reckon that that would give us as a species around 200 to 300 years at most and possibly a lot fewer. It is perhaps proof that the denialati don't really believe that we are not to blame for climate change because there is a marked absence of wailing and gnashing of teeth on their part. But we should not let such absence of concern by them deflect us from taking the action that becomes ever more urgent with each passing moment.
  23. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    Re Malloy it's a terrific thing to hear from a public servant who's able to look to the future and understand an object lesson even while dealing with immediate contingencies.
  24. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    Thank you, Doug. Technically, I see that the 11 am update is now showing the inlets southwest of Manhattan are potentially looking at higher storm surges than western Long Island Sound. Down along our shoreline, however, we have a lot of residential neighborhoods. Our governor here in Connecticut, Dannel Malloy, just held a noon press conference in which he made a few subtle yet telling remarks. He pointed out that the storm is unprecedented, yet noted that it was a wake-up call for all of us. The two specific points he made were that our state would need in the future to plan for similar events that have the potential to knock out our electrical grids and sewer systems in low-lying areas. It turned out that an electrical substation in Bridgeport, Connecticut, almost needed to be shut down. Malloy said the storm surge was a matter of 8 to 10 inches shy of causing a shutdown at the point of high tide. The prediction is safety shutdowns will be required this evening going into the next high tide. Of course, we are already seeing wind-caused power outages all over the state, even though the wind is still barely gusting to tropical storm strength. I think one of the interesting facts about this storm and last October's snow storm is that we are seeing a convergence of traditionally winter and summer weather events here in the northeast. All that extra energy in the climate system is finding new ways to act.
  25. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    Grinsted, that's a very interesting and timely paper. Thank you.
  26. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    That's an excellent point about time correction for tides, Don. The more complicated the coast line, the more arrival of tides varies from location-location. Here's a pretty nice tool for deducing tide timing in specific locations in the NE: Nor'East Saltwater Tide Charts
  27. Rose and Curry Double Down on Global Warming Denial
    We can add this recent one to Doug's list: Sedláček & Knutti (2012). Abstract: “Of the additional energy absorbed by the Earth over the past decades, by far the largest fraction is taken up by the oceans. Yet most attribution studies focus on the surface warming, and only few have used patterns of ocean warming to attribute changes to external forcing or internal variability. Here we use the combined observed evidence from warming of the atmosphere and ocean with the latest climate model simulations to demonstrate that both the depth profiles and spatial warming patterns near the surface are very heterogeneous when resulting from internal unforced variability. In the 20th-century simulations on the other hand, the observed spatial pattern is smooth, and the warming decreases almost gradually with depth in the ocean, consistent with observations and a penetration of the surface warming to intermediate depth by diffusion and advection. We argue that such physically motivated arguments combining different lines of evidence and types of observations offer insight that is complementary to optimal fingerprint attribution methods. We conclude that the simultaneous global warming of the atmosphere and mixed layer alone is uninformative for attribution, but the magnitude of ocean heat uptake, the homogeneity of the spatial pattern as well as the distribution of warming below the mixed layer strongly argue for the 20th-century warming being largely externally forced.” The bibliography for that paper should of tremendous help to you, Bill, and I would expect you to use some of the works referenced if you continue, here, your public thought on the subject. You may also want to check out the Knutti & Plattner (2011) response to Schwarz et al. (2010) -- and the works referenced. Ocean warming is an extremely complex process, with dozens of distinct circulation/mixing mechanisms both large and small. Check out Ari's research blog (usually reprinted at SkS) on the subject here. If you don't have access to the journals, let the blog know, and someone may be able to finagle a copy of the article you need.
  28. Rose and Curry Double Down on Global Warming Denial
    BillHunter Let's assume for a moment that there were indeed no direct measurements of an energy imbalance (note: even the decreasing amount of outgoing infrared (aka heat-) radiation from Earth into space has been measured). Then we would still know that greenhouse gases (GHGs) have increased in Earth's atmosphere (not disputed by anyone). Our knowledge of the physical properties of those GHGs says that they will "trap" heat radiation, a well-known mechanism, also not disputed. This then is roughly equivalent to putting a pot of water (Earth) on the stove and turning the heat on (GHG). Self-named "skeptics" still allege that the water in that pot will not get warmer despite the "energy imbalance" the stove is creating. (-snip-)
    Moderator Response: [DB] Text snipped per request.
  29. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    Just a brief note: Dr. Masters mentions 9 p.m. for the high tide. That is probably for the Manhattan or central NYC area in general. In Long Island Sound, where the storm surge is likely to be the most severe, the high tide times for tonight range from about 10 p.m. at the eastern end to midnight in the western end where the most water will pile up. I'm glad I'm in West Hartford, Connecticut, well above the current sea-level.
  30. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    Recently in the news and discussed at Skeptical Science was the effort by North Carolina legislators to set boundaries on what information could inform public policy concerning coastal development. Virginia has been tempted to go down the same path. Sandy's arrival reminds us of the folly of trying to legislate facts not amenable to or concerned with matters of law.
    Worth noting in this context is the move just over a month ago by the NSW conservative government to do away with the necessity for local councils to consider, when assessing development proposals, IPCC sea level rise predictions. Someone with a bit of nous might put them on notice that Sandy demonstrates why this was a negligent move, and why the government might be considered culpable for future flooding of new developments. If only the relevant politicians could be held accountable for any future damage that results from this policy change...
  31. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    I recently published a paper on hurricane surge threat finding greater and more frequent hurricane surges in globally warm years compared to cold. This was looking at extremes in tide gauge data since 1923. This is just a correlation ofcourse, but it certainly makes me wonder about the future.
  32. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    Heh, I've been looking around for detailed information on the storm. Should have come here first. Nothing too bad here yet, but the wind has been steadily picking up since Sunday morning. I work in Newark, but my office is shut down today and tomorrow along with most of the rest of the city. My biggest worry ATM is another power outage like we had with Irene and then the big snowstorm this time last year. Both of those were followed by fairly warm weather, but this time they are predicting a cold snap after the storm. They finally started upgrading the infrastructure after those outages and the solar energy boom here in New Jersey has also been helping to push towards a more modern power grid. Among other things, they've installed individual solar panels on a few hundred thousand telephone poles around the state. Each of these is tied in to the electric line running on the same pole and capable of reporting back current power flow (along with performance of the solar panel and other data). That should immediately let them know where there are power outages, but we'll have to see how well it holds up.
  33. Climate of Doubt Shines a Light on the Climate Denial Movement
    It doesn't seem to me that an energy imbalance has been observed. Its hypothesized. If I am wrong about that I would be interesting in reading about it. (-SNIP-)
    Moderator Response: (Rob P) The oceans have warmed - that is where 93% of the energy imbalance has gone in the last 5-6 decades. That you do not comprehend this rather simple observation implies poor understanding on your part. And as stated earlier, time to start providing some supporting literature to back up your claims.
  34. Rose and Curry Double Down on Global Warming Denial
    Long waffle rewound to original essence: Billhunter: It [deep ocean warming] has in fact not been measured. But it has. If somebody disagrees, they need to do a proper literature search and then effectively contradict findings therein. "I doubt it" is not an argument.
  35. Rose and Curry Double Down on Global Warming Denial
    Doug thanks for you comments. (-SNIP-)
    Moderator Response: (Rob P) - The cornerstone of this site is peer-reviewed science. Time to start backing up some of your inventive claims with some peer-reviewed literature.
  36. Doug Hutcheson at 16:49 PM on 29 October 2012
    Climate of Doubt Shines a Light on the Climate Denial Movement
    Bill, you said
    "Is there any evidence that the global warming trend has slowed in the last decade or so compared to its previous trend during the 90s?" Well yes. The surface stations.
    But, as has been pointed out earlier, land surface stations measure only a small percentage of global warming. The globe in question includes atmosphere, land surface, cryosphere and oceans. When you look at all the temperature measurements, not just land surface stations, has the warming trend changed by any significant amount? When you look at the energy imbalance between incoming and outgoing radiation, it is clear that energy is being absorbed somewhere in the global system. Where do you think it is going and what form does it take? (Hint: something is melting Arctic ice and warming the oceans.) If you look only at a short period of land surface temperatures, the noise drowns out the signal, so it is not a useful metric, unless you want to obfuscate the evidence.
  37. Climate of Doubt Shines a Light on the Climate Denial Movement
    Well yes. The surface stations.
    Well, no -- and that's the point. The surface station records show a flattening in the past decade or so that makes it look like the long term warming trend might have slowed when viewed in isolation, but the whole point of the escalator graphic is that this has occurred many times in the past and every time it turned out that the underlying global warming trend kept right on going, so we need to figure out if this time is any different. (The point of the Foster and Rahmstorf graphic right below it is to highlight this fact and make it easier to discern the trend in less time by removing the influence of exogenous factors, effectively improving the signal:noise ratio.) My question was "Is there any evidence that the global warming trend has slowed?". To answer that question you need to assess the statistical significance of the recent apparent change in trend. The whole point of "arguing statistics" is to make sure we're not being fooled by what we think we see in the data. If you don't want to argue the statistics or put the effort in to working out whether recent surface station records signal a reduction in trend then you can't go around claiming that they indicate less warming in the future than projected. If you do want to go around making that claim (???) then you have no choice but to do the work to see if the data supports that claim. After all, how can you make that claim without already knowing it's true from having analysed the data? The question about whether we should act and what should be done is completely besides the point and the subject of other posts here.
  38. Climate of Doubt Shines a Light on the Climate Denial Movement
    "Is there any evidence that the global warming trend has slowed in the last decade or so compared to its previous trend during the 90s?" Well yes. The surface stations. I think its normal that the number of people who think the globe has warmed and that mankind is in someway responsible is going to fluctuate with the weather. You can number me in that group. I am not particularly strong on the man-caused question but give the choice between yes and no I would have to pick yes. Its the number of people who think something should be done about it thats below 50%. And you can put me in the category of being in the minority there was well. For instance I think solar water heating systems with demand water heating should be mandated for new construction and I think persons looking at newly constructed homes should consider paying a bit more for a home with excess insulation and radiant heating systems running off of solar heating panels either as a primary source of heat, with or without supplementation. Though that's probably a little expensive to mandate. So apparently I am in the minority with you guys on the question of doing something, but probably differ on what should be done. But lets not argue statistics. Lets keep this simple and relevant to public opinion. Statistics is really off topic here I think. (-SNIP-)
    Moderator Response: [DB] For someone who claimed to be a statistician, your claim to now not want to discuss statistics rings hollow and is specious. Statistics on a science-based site are always in play. Your evasion to the responses you have generated is noted. Please return the discussion to that of the OP of this thread. Off-topic snipped.
  39. Rose and Curry Double Down on Global Warming Denial
    Billhunter It [deep ocean warming] has in fact not been measured.
    Johnson GC et al. (2006) Recent western South Atlantic bottom water warming Geophys. Res. Lett. 33, L14614 Abstract: Potential temperature differences are computed from hydrographic sections transiting the western basins of the South Atlantic Ocean from 60 degrees S to the equator in 2005/ 2003 and 1989/1995. While warming is observed throughout much of the water column, the most statistically significant warming is about + 0.04 degrees C in the bottom 1500 dbar of the Brazil Basin, with similar ( but less statistically significant) warming signals in the abyssal Argentine Basin and Scotia Sea. These abyssal waters of Antarctic origin spread northward in the South Atlantic. The observed abyssal Argentine Basin warming is of a similar magnitude to that previously reported between 1980 and 1989. The Brazil Basin abyssal warming is similar in size to and consistent in timing with previously reported changes in abyssal southern inflow and northern outflow. The temperature changes reported here, if they were to hold throughout the abyssal world ocean, would contribute substantially to global ocean heat budgets. Johnson GC et al. (2007) Recent bottom water warming in the Pacific Ocean J. Climate 20, 5365-5375. Abstract: Decadal changes of abyssal temperature in the Pacific Ocean are analyzed using high-quality, full-depth hydrographic sections, each occupied at least twice between 1984 and 2006. The deep warming found over this time period agrees with previous analyses. The analysis presented here suggests it may have occurred after 1991, at least in the North Pacific. Mean temperature changes for the three zonal and three meridional hydrographic sections analyzed here exhibit abyssal warming often significantly different from zero at 95% confidence limits for this time period. Warming rates are generally larger to the south, and smaller to the north. This pattern is consistent with changes being attenuated with distance from the source of bottom water for the Pacific Ocean, which enters the main deep basins of this ocean southeast of New Zealand. Rough estimates of the change in ocean heat content suggest that the abyssal warming may amount to a significant fraction of upper World Ocean heat gain over the past few decades. Johnson GC (2008) Warming and Freshening in the Abyssal Southeastern Indian Ocean J. Climate 21, 5351-5363. Abstract: Warming and freshening of abyssal waters in the eastern Indian Ocean between 1994/95 and 2007 are quantified using data from two closely sampled high-quality occupations of a hydrographic section extending from Antarctica northward to the equator. These changes are limited to abyssal waters in the Princess Elizabeth Trough and the Australian-Antarctic Basin, with little abyssal change evident north of the Southeast Indian Ridge. As in previous studies, significant cooling and freshening is observed in the bottom potential temperature-salinity relations in these two southern basins. In addition, analysis on pressure surfaces shows abyssal warming of about 0.05 degrees C and freshening of about 0.01 Practical Salinity Scale 1978 (PSS-78) in the Princess Elizabeth Trough, and warming of 0.1 degrees C with freshening of about 0.005 in the abyssal Australian-Antarctic Basin. These 12-yr differences are statistically significant from zero at 95% confidence intervals over the bottom few to several hundred decibars of the water column in both deep basins. Both warming and freshening reduce the density of seawater, contributing to the vertical expansion of the water column. The changes below 3000 dbar in these basins suggest local contributions approaching 1 and 4 cm of sea level rise, respectively. Transient tracer data from the 2007 occupation qualitatively suggest that the abyssal waters in the two southern basins exhibiting changes have significant components that have been exposed to the ocean surface within the last few decades, whereas north of the Southeast Indian Ridge, where changes are not found, the component of abyssal waters that have undergone such ventilation is much reduced. Ozaki H et al. (2009) Long-term bottom water warming in the north Ross Sea J. Oceanograph. 65, 235-244. Abstract: We measured potential temperature, salinity, and dissolved oxygen profiles from the surface to the bottom at two locations in the north Ross Sea (65.2A degrees S, 174.2A degrees E and 67.2A degrees S, 172.7A degrees W) in December 2004. Comparison of our data with previous results from the same region reveals an increase in potential temperature and decreases in salinity and dissolved oxygen concentration in the bottom layer (deeper than 3000 m) over the past four decades. The changes were significantly different from the analytical precisions. Detailed investigation of the temperature, salinity, dissolved oxygen and sigma (3) value distributions and the bottom water flow in the north Ross Sea suggests a long-term change in water mass mixing balance. That is to say, it is speculated that the influence of cool, saline, high-oxygen bottom water (high-salinity Ross Sea Bottom Water) formed in the southwestern Ross Sea has possibly been decreased, while the influences of relatively warmer and fresher bottom water (low-salinity Ross Sea Bottom Water) and the Ad,lie Land Bottom Water coming from the Australia-Antarctic Basin have increased. The possible impact of global warming on ocean circulation needs much more investigation. Johnson GC et al. (2009) Deep Caribbean Sea warming Deep Sea Research. 1 –Oceanograph. Res. 56, 827-834. Abstract: Data collected from hydrographic stations occupied within the Venezuelan and Columbian basins of the Caribbean Sea from 1922 through 2003 are analyzed to study the decadal variability of deep temperature in the region. The analysis focuses on waters below the 1815-m sill depth of the Anegada-Jungfern Passage. Relatively dense waters (compared to those in the deep Caribbean) from the North Atlantic spill over this sill to ventilate the deep Caribbean Sea. Deep warming at a rate of over 0.01 degrees C decade(-1) below this sill depth appears to have commenced in the 1970s after a period of relatively constant deep Caribbean Sea temperatures extending at least as far back as the 1920s. Conductivity-temperature-depth station data from World Ocean Circulation Experiment Section A22 along 66 degrees W taken in 1997 and again in 2003 provide an especially precise, albeit geographically limited, estimate of this warming over that 6-year period. They also suggest a small (0.001 PSS-78, about the size of expected measurement biases) deep freshening. The warming is about 10 times larger than the size of geothermal heating in the region, and is of the same magnitude as the average global upper-ocean heat uptake over a recent 50-year period. Together with the freshening, the warming contributes about 0.012 m decade(-1) of sea level rise in portions of the Caribbean Sea with bottom depths around 5000 m. Johnson GC (2008) Reduced Antarctic meridional overturning circulation reaches the North Atlantic Ocean Geophys. Res. Lett. 35, L22601 Abstract: Potential temperature differences are computed from hydrographic sections transiting the western basins of the South Atlantic Ocean from 60 degrees S to the equator in 2005/ 2003 and 1989/1995. While warming is observed throughout much of the water column, the most statistically significant warming is about + 0.04 degrees C in the bottom 1500 dbar of the Brazil Basin, with similar ( but less statistically significant) warming signals in the abyssal Argentine Basin and Scotia Sea. These abyssal waters of Antarctic origin spread northward in the South Atlantic. The observed abyssal Argentine Basin warming is of a similar magnitude to that previously reported between 1980 and 1989. The Brazil Basin abyssal warming is similar in size to and consistent in timing with previously reported changes in abyssal southern inflow and northern outflow. The temperature changes reported here, if they were to hold throughout the abyssal world ocean, would contribute substantially to global ocean heat budgets. Fukasawa, Masao, et al. "Bottom water warming in the North Pacific Ocean." Nature 427.6977 (2004): 825-827. Observations of changes in the properties of ocean waters have been restricted to surface1 or intermediate-depth waters2, 3, because the detection of change in bottom water is extremely difficult owing to the small magnitude of the expected signals. Nevertheless, temporal changes in the properties of such deep waters across an ocean basin are of particular interest, as they can be used to constrain the transport of water at the bottom of the ocean and to detect changes in the global thermohaline circulation. Here we present a comparison of a trans-Pacific survey completed in 1985 (refs 4, 5) and its repetition in 1999 (ref. 6). We find that the deepest waters of the North Pacific Ocean have warmed significantly across the entire width of the ocean basin. Our observations imply that changes in water properties are now detectable in water masses that have long been insulated from heat exchange with the atmosphere. Kawano, Takeshi, et al. "Bottom water warming along the pathway of Lower Circumpolar Deep Water in the Pacific Ocean." Geophysical research letters 33.23 (2006): L23613. Repeat trans-Pacific hydrographic observations along the pathway of Lower Circumpolar Deep Water (LCDW) reveal that bottom water has warmed by about 0.005 to 0.01°C in recent decades. The warming is probably not from direct heating of LCDW, but is manifest as a decrease of the coldest component of LCDW evident at each hydrographic section. This result is consistent with numerical model results of warming associated with decreased bottom water formation rates around Antarctica.
    Etc. For some reason there's a widely held wrong belief that we know nothing of abyssal temperatures.
  40. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    An article in the NY Times does a fine job of explaining some of the mechanics of storm surge, why the region Sandy is expected to hit is at particular risk: Shallow Waters and Unusual Path May Worsen the Surge
  41. citizenschallenge at 14:08 PM on 29 October 2012
    Rose and Curry Double Down on Global Warming Denial
    Dana another great post. Keep up the great work. I thought I should let you know that I wrote my own post regarding Rose's meme over at my little WhatsUpWithThatWatts.blogspot.com I mention it because after I finished with what I wanted to say - I posted this article. You know, to follow up with plenty of serious resources. So a big Tip Of The Hat for SkepticalScience's generous sharing and reposting policy. http://whatsupwiththatwatts.blogspot.com/2012/10/david-roses-global-warming-stopped-16.html
  42. Rose and Curry Double Down on Global Warming Denial
    Old Mole thanks for your comments. I agree my comments do not have anything to do with convection near the poles. But I have never seen 4c water off California's coast, much less seen it pushing any water under it. I have to assume it doesn't happen at the equator either. And yes I agree living at the coast in southern California is great, cool summers and balmy winters thanks to the California current. When I said the average temperature of the ocean is around 5C or less, I was not talking about the surface which might be 17C. There must be sufficient downwelling of water colder than 5C to maintain it at that average temperature as the surface is constantly conducting heat downwards and the ocean floor is conducting heat up into a cold ocean. Downwelling of water warmer than 5c will not maintain the ocean at 5C. So that implies that the ocean has overridden all or part of the greenhouse effect as far as its average temperature is concerned. Unusual upwelling at the equator over time could be indicative of a natural variation on this on going negative feedback process. A possible mechanism is ice retreat. If the ice edge moves north its fairly reasonable to assume the downwelling zones will also move north. If they move north they will have a larger area where it will be cold enough to downwell. Obviously a larger Arctic halocline would offset that in some way, but is there any evidence the halocline is increasing in size? I guess that's a possibility but that merely adds to the problem of figuring where the additional upwelling cold water that has dominated the last decade is coming from. I think we can assume some of it comes from the ongoing negative feedback process that keeps our oceans cold. . . .on average. I recall Jim Hansen back in 2000 declaring that El Ninos were the new normal. Since then there has been an expectation of repetitions of 1998. But what we see is just the opposite. An emerging La Nina dominance not seen for quite a while. Unfortunately most of the measures of the ocean are in the upper 700 meters. (-snip-). 700 meters represents the warmest 18.5% of the ocean. If upwelling and downwelling is concentrated in limited areas it makes sense that downwelling conduction could have warmed the ocean between 700 meters and the bottom of the mixing zone (or even maybe deeper) from recent ocean surface warming even while the ocean cooled overall and provided additional cold water for the surface. Let me be clear. I am not saying thats the case. I am saying that contrary to Michael Sweet's statement that the science is mixed on deep ocean warming or cooling. It has in fact not been measured. (-snip-). Bottom line is the ocean is not a good explanation for the missing heat. Most studies of OHC come up way short. That spawned the idea that the heat was migrating below our measurements. But no mechanism for that has been proposed and ocean surface warming has been lagging so its not likely conduction from the mixing layer of the ocean which has also experienced a slowing in warming. But we know less about the bottom of the ocean than we do the surface of planet Mars. In the interest of full disclosure I am an ocean guy so I want to see more funding for research in the oceans.
    Moderator Response: [DB] Intimations of impropriety snipped. Let me be clear: Please re-read the Comments Policy. Subsequent comments constructed as this one will be summarily deleted in their entirety. Please also note that unsupported assertions, as you make, that have been debunked on multiple occasions constitute sloganeering, itself another Comments Policy violation.
  43. Climate of Doubt Shines a Light on the Climate Denial Movement
    Bill,
    Pre-1980's the risers were lower and the treads longer. For the 80's and 90's the risers get higher and the treads shorter.
    You say this as if the "trend" lines in the escalator mean anything, and as such is evidence that you are entirely missing the point, and yet you go on to say
    Somebody can draw various trends through the data and point out all sorts of interesting stuff.
    Yes, that's exactly the point, if you play games. There are no "risers" and "treads". There is no "polynomial fit." All of that is nonsense, as the Escalator demonstrates and as Spencer well knows. You take a long enough trend, and compute a proper linear trend line. If you break the trends up, you do it for valid, physical reasons following rules that you establish before you begin carving, not after. This is all about playing games with numbers, and it's a waste of everyone's time. There is only one thing that the numbers consistently and indisputably say, and that is that the climate is warming steadily and dangerously. If that warming seems to have slowed, then there are only two possibilities. One is that a number of negative factors are combining to minimize the warming for a time. This would be very, very bad if people accept it as an excuse for inaction, because there will inevitably be another period where temperatures "catch up," and people will be stunned by what that means. Alternately, we could be finding that the rate of warming is slower than expected. The setting of the thermostat is still the same. We have at this point committed ourselves to about 1.4˚C of warming, no matter what we do, and because of our lack of progress in reducing emissions, since we can't simply go "cold turkey," many argue that when you consider the future emissions that we cannot avoid, we are already committed to a temperature rise of well beyond 2˚C. So if we're committed to such a rise, but the rise is slower than expected (either only in the short term, due to temporary, negative factors, or over the long term, due to the "sluggishness" of the system), in either case we are in very bad shape if people continue to use that to argue for inaction. Because the reality is that regardless of pace, we are committed to a dangerous increase in the earth's climate, and the longer we delay, the worse the end result will be, no matter how long it takes. People need to wake the F up.
  44. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    I've already encountered a "skepticons" argument that the energy of this storm is built upon the surging cold front and this cold front is evidence of a "global cooling which is on the rise". At what point do you throw your hands up and walk away, head into the kitchen, open the fridge and pull out a frosty adult beverage, go to the porch and watch the sunset? On the other hand...as this storm is tracking straight into the liberal elite's heartland as well as the center of both financial and political power, is there a possibility that this could be an event of seminal importance in tipping the scale of awareness toward honest and objective analysis of the mountain of evidence that has built into an Everest? As is our nature, action, albeit reactive, will be determined by a body count of inescapable sadness and tragedy; anything less than rows of body bags and this storm will be just another History Channel footnote.
  45. Climate of Doubt Shines a Light on the Climate Denial Movement
    Bill, The fact that you are trying to draw inferences from the perceived change in appearance of those trends suggests you have rather missed the point, which was this: you can't infer anything when the period is too short because the signal is swamped by noise. I'd also like to point out that those trends were deliberately cherry-picked to maximise the effect, and that your "observations" completely fall over as soon as a different temperature series is picked, as with the original escalator graphic. In that case you could argue that because the cherry-picked trends have greater negative slope from the early 80s to the mid-90s and that it's harder to find such negative trends now, warming has actually accelerated. But if you really want to analyse the data, rather than drawing inferences from the shapes of trends that were cherry-picked for dramatic effect, I suggest you ask yourself the following question: Is there any evidence that the global warming trend has slowed in the last decade or so compared to its previous trend during the 90s? As a statistician you can calculate the trend prior to 1997, say; then see whether the data since 1997 fits within the 95% confidence interval of that prior trend extrapolated to today. (Of course you need to account for autocorrelation in order to calculate the 95% confidence intervals.) Do that with each of the global temperature data sets. Assuming you find that the answer is "no", then ask yourself: If there is no statistically significant evidence of a change in trend since 1997, how can we say that global warming has slowed? Regarding 4th order polynomials -- of course that's inferior. If the data is noisy, you don't make it easier to capture the underlying behaviour and make useful predictions by giving your model more degrees of freedom! Every additional parameter has to be shown to be justified. Adding a linear term to a model of global temperatures since the 1970s, for example, clearly results in a better model than a model that simply has a constant temperature term. But models with more parameters will be worse according to the Akaike information criterion for that period in time. Over longer periods, when other factors come into play, then additional parameters may be justified. There's another important reason for a linear trend that's not just based on the statistics -- it's called Physics. We expect a linear increase due to the exponential increase in CO2 emissions coupled with the logarithmic nature of CO2 concentrations on temperature. From knowledge of the problem itself we can predict what model should work best. Roy Spencer knows this as well, which is why he says it's for "entertainment purposes only" and doesn't offer it as an argument. If he didn't know it was inferior, as you apparently don't, then he wouldn't have to say that, he could defend it. It's easy to construct a higher-order polynomial that shows temperature about to embark on a precipitous increase, but I doubt you'll find anybody here posting one "for entertainment purposes only". Something to think about.
  46. Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
    Just noticed that Michael Tobis connected some dots on this story, way back when on the 25th. Grim Trajectories.
  47. 2012 SkS Weekly Digest #43
    My favorite quote of the week, as heard on "Klick and Klack" of NPR, one that seems appropriate when thinking about how e do or don't deal w/our C02: "Is your problem ignorance, or apathy?" "I don't know and I don't care." From a recitation of quotes from college sports coaches. Another good one: "Son, you got four "F" grades and a "D." It looks like you're focusing too much on one topic."
  48. 2012 SkS Weekly News Round-Up #7
    Estiben: We've gone directly from denial to nihilism. Denihilism?
  49. 2012 SkS Weekly News Round-Up #7
    Agreed, ranyl. I found the ABC article depressing. That seems to be the narrative these days, "it's too late to stop warming, so we just have to figure out how to live with it." We've gone directly from denial to nihilism. How do we convince the public that admitting there is a problem doesn't mean giving up to it? We can't undo global warming, but we can keep it from being the worst case, while we also adapt to the inevitable consequences.
  50. Climate of Doubt Shines a Light on the Climate Denial Movement
    _________________________________________________________ I apologize for getting too wordy and out of topic in my last response so I rewrote it below. Feel free to erase the previous post so I am in compliance with your posting policy. I have read the policy and will try to adhere to it. _______________________ The climate escalator graphic is pretty revealing. Especially in the video screenshot version. Pre-1980's the risers were lower and the treads longer. For the 80's and 90's the risers get higher and the treads shorter. The IPCC projections for the future projected an even higher step for the coming decades. But for the 2000's the riser got a lot shorter than the 80's and 90's and the tread a lot longer than ever. Seems to me until the next step comes its suggesting or matching what many scientists have been saying about an oscillating climate possibly suggesting less warming for the future than projected. Obviously one such step is not very convincing to somebody already convinced, but it is a bit of problem for convincing those who are not convinced. Somebody can draw various trends through the data and point out all sorts of interesting stuff. But statistically the less these curves comply with each other the more uncertainty that suggests. Regarding statistical trends Roy Spencer at his blog has been drawing a 4th order polynomial fit that is just another view of the trend, not superior, not inferior. Spencer though acknowledges his trend is for "entertainment purposes only" and doesn't offer it as an argument.

Prev  1035  1036  1037  1038  1039  1040  1041  1042  1043  1044  1045  1046  1047  1048  1049  1050  Next



The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us