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Eric the Red at 07:22 AM on 19 June 2011Linking Extreme Weather and Global Warming
There are several reference to the relationship between temperature and snowfall. Those areas which are belwo freezing for most of the year will likely see an increase in snowfall as temperatures approach freezing. Thesse areas are few. The rest will experience more days above freezing, and hence more rainfall amd less snowfall. http://onlinelibrary.wiley.com/doi/10.1002/joc.1014/pdf http://www.springerlink.com/content/k631170346751481/ -
Eric (skeptic) at 07:02 AM on 19 June 2011Linking Extreme Weather and Global Warming
A proxy for poleward migration of the subtropical jet (i.e. expansion of the Hadley cells) is lower stratospheric cooling at 30 degrees latitude, see http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00027.1 The TLS plot showing latitude cross section does show some slight cooling at 30 degrees:
ignoring the two volcanoes. But that cooling seems to have leveled off.
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adrian smits at 06:54 AM on 19 June 2011Linking Extreme Weather and Global Warming
When you're talking about the current temperature it should have a bigger impact on the weather than the 5 year average temps. All I said was it appears cooler temps seem to create more violent weather events than a supposedly warming climate! -
Norman at 06:36 AM on 19 June 2011Linking Extreme Weather and Global Warming
Sphaerica @41 Here is an interesting article on Hadley cells. Info on Hadley Cells. -
Norman at 06:31 AM on 19 June 2011Linking Extreme Weather and Global Warming
Tom Curtis @ 37 Here is some information you may find useful. History of Australia's droughts and causes. You may want to look at page 3 and below to see if global warming is causing an increase in severity of Australian droughts. Here is a quote from that page: "Many scientists believe that human activities associated with the generation of ‘greenhouse gases’ are causing climate change. (See STUDIES 2/2000.) This, however, does not cause drought as it has been experienced in Australia over thousands of years. Natural climate change in Australia is caused by two major elements – the changes in the pressure of air in the atmosphere circulating between Tahiti and Darwin (measured by the Southern Oscillation Index – SOI); and the temperature of currents moving across the equator from South America to the area to the north of Australia (known as the El Niño effect)." -
Bob Lacatena at 03:29 AM on 19 June 2011Linking Extreme Weather and Global Warming
38, Eric the Red, I have found that one of the easiest ways to understand just one mechanism by which precipitation will change, and how that mechanism will be affected by climate change (and this change is already being observed), is to study the Hadley Cells. It's a fascinating subject, and easy to grasp. A quick Google will find you something at an introductory level, and you can go from there. The basic idea, however, is that the intense warming at the equator (or rather, at the point of direct 90˚ solar incidence, which is at the equator in spring/fall but moves up/down a bit with winter/summer) causes that air to rise, laden with moisture. This cycles up, then north/south, then reaches a point where it falls back down. The first point is that the area where it comes back down sees a lot of rain. The area in between is parched, and most of the world's deserts lie in these bands (but are, of course, subjected to other, local factors). Have a look at the globe and notice how most of the worlds deserts are just north and south of the equator, yet not at the equator, or just north of that arid band. Because the point of 90˚ incidence moves with the seasons, so do the Hadley Cells, bringing seasonally consistent/predictable rainfall or dry periods to certain regions. An increased global temperature will increase the size of the Hadley Cells (again, this has already been observed, so while it's not carved in stone, it looks to be true and hard to argue). This means that those deserts will expand... the intervening arid areas will be larger. It also means that some places that used to get seasonal rains will not any longer, while places that didn't get them (i.e. were just outside the Hadley Cell at the right time of year) suddenly do see that precipitation. Spend some time reading up on it. It's a fun subject, and helps to move one beyond the too simplistic "an increase in rainfall due to increased moisture" point of view. It's obviously not that simple, and scientists are aware of it, even if we ourselves are not (always). Very interestingly, two regions of the earth that will be subjected to climate change through this rather easy to understand mechanism (Hadley Cell expansion) are Australia and Texas, who are both in a way "big players" in climate denial. -
Robert Murphy at 03:20 AM on 19 June 2011Hansen's 1988 prediction was wrong
Disregard my above post, I misread the column from the Realclimate link. :) -
trunkmonkey at 02:52 AM on 19 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
Chris @ 33 I found downloadable Kent and Muttoni PDF some weeks ago by googling it. I was very skeptical of this notion at first because in classic plate tectonic theory carbonate sediments are too light to be subducted and are scraped off at the continent/arc margin. It now appears that within the last decade or so various isotopic analyses indicate that there are both low and high sediment flux trenches.I have not yet found any remotely articulate explanation for what feaures (angle?)might account for the difference. Tethys is thought to have been shallow and at first glance seems an excellent candidate for substantial carbonate sediment buildup. Closer analysis reveals that the Tethys ocean floor was extremely active, with two spreading centers through most of the Mesozoic. Much carbonate sedment may have already beern subducted or scraped off prior to India's excursion. Unfortunately there is no modern tectonic analogue. There is, however, active rifting going on today in the Red Sea and the Gulf of California.If Lee Kumps "baking carbon rich sediments and perhaps even some coal and oil near the surface."is to be taken seriously, we should see carbon anomolies in these areas. Apparent polar wander paths indicate that the rifting of Greenland from Europe and America was well under way 80mya in the Cretaceous. -
JMurphy at 02:48 AM on 19 June 2011Linking Extreme Weather and Global Warming
With regard to snow and cold Winters : From Weather Underground : That it is snowy does not suggest that it is colder. If it gets warmer, it does not mean that we no longer see freezing temperatures in places like Michigan. If it gets warmer there is more water in the atmosphere, and when there is precipitation there will be more precipitation, and if it is below freezing, then that precipitation will be ice and snow. From a climate point of view it is more important to look at snow cover in the late winter and early spring. Is the snow melting earlier? And from this very site : Does record snowfall disprove global warming? And, from the Union of Concerned Scientists : It’s Cold and My Car is Buried in Snow. Is Global Warming Really Happening? -
jerryd at 02:27 AM on 19 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
Chris – Yes, by the exogenic carbon cycle, I mean pretty much everything on Earth’s surface within a few meters of sedimentary depth. To be honest, it’s a hard concept to describe rigorously, as I found out on NPR about 15 years ago. When asked what the exogenic carbon cycle is, I think I said something like “well, it’s like if you took all the carbon in the ocean, the atmosphere, and on land including soil, trees, plants, animals and newts and put them in a blender.” [I have no clue why I said newts and blender, but it went across the airwaves, and several colleagues continually poke me on this comment]. Basically, it is all carbon that can exchange on geologically short time scales. The idea of slow (million-year) carbon changes caused by tectonism is certainly plausible. I have not yet read the paper by Kent and Muttoni, but will do so shortly. Rob – Thanks for passing along the Beerling reference. I have not yet seen or read this paper either. It certainly looks very interesting. [Here I think an interesting aside: I know both Dennis Kent and Dave Beerling personally, and appreciate their work very much. They are both top-notch scientists. That I have not read these works, I think, signals the state of the field – it is moving really fast. It was easy to keep up with things regarding early Paleogene climates 5-10 years ago, but numerous papers are now coming out every week. I probably need to do some more reading rather than blogging!]. Anyway, there are several major problems with understanding “early Paleogene” climates (here loosely meaning the time from about 62 to 45 million years ago). One is the “hyperthermal problem” noted in previous posts. How do massive amounts of carbon enter the exogenic carbon cycle quickly (and according to recent papers) repeatedly? Another is the “equator-to-pole gradient problem”. All data consistently suggests that the equator-to-pole temperature gradient was much lower in the early Paleogene relative to present-day. That is, the equator was ~5 °C warmer than today but the poles were ~25 °C warmer than today. Some of this problem is solved by the removal of ice (the albedo effect); some of this problem may lie in the use of proxies for past temperature, namely that many records generated at high latitudes may be biased toward summer temperatures. Even after this accounting, the poles seem too warm (or the equator seems too cold) in coupled climate models for the early Paleogene. Matt Huber has a current paper discussing the problem (http://www.clim-past.net/recent_papers.html). This is where I think Dave Beerling might be correct: trace gases may explain the discrepancy. Sphaerica – Great questions. 1/ All sorts of things are conceivable. However, I think that the geological record is telling us that we do not have an appropriate view for how carbon cycles on Earth’s surface. 2/ Several people have done this (notably Bob Berner at Yale). But, a roadblock hits at the PETM, because it is impossible to explain this event within the context of conventional modeling of carbon cycling. Basically, one needs to invoke an "ad hoc" mechanism for carbon transfer. This may be correct, if for example, the source of carbon came via intrusive volcanism. I am 99% sure, however, that we need to rethink how the global carbon cycle operates over geological time. -
dhogaza at 02:22 AM on 19 June 2011How would a Solar Grand Minimum affect global warming?
I suppose (to answer my own question) it will help to tighten the bounds of the minimal change in forcing that's been computed with observations available thus far ... more data will help do so regardless of whether the minimum predicted by some comes to pass or not, though ... -
dhogaza at 02:21 AM on 19 June 2011How would a Solar Grand Minimum affect global warming?
The solar contribution to warming, if any, will be determined, and any more speculation will have ended.
How will the next minimum - if it happens as predicted - tell us much more than we've been learning observing TSI over the last several decades, including the several years of the current minimum? -
Rob Honeycutt at 02:09 AM on 19 June 2011Phil Jones - Warming Since 1995 is now Statistically Significant
MoreCarbonOK... There is an old saying. "If you can't stand the heat..." To be quite honest, these guys are not pushing very hard on you. They're only subjecting you to the very lightest of skepticism that every scientist gets put to when publishing work. If you want to do science as a hobby then you should at least accept some of the pressure that any scientist would expect as routine in their research. Brandishing claims of corruption just doesn't cut it. It's a rather un-skeptical cop out. -
michael sweet at 02:08 AM on 19 June 2011Speaking science to climate policy
Ken, Apparently the link I provided for you in 13 did not work for you. here it is again. After you have read the section on thermal inertia and unrealized warming we can discuss this further. It would be better to post your questions on that thread since it is on topic there. -
michael sweet at 01:58 AM on 19 June 2011Linking Extreme Weather and Global Warming
Eric: Please cite references. It is well known that AGW theory predicts more precipitation in all seasons. During the winter this falls as snow. The last two winters were historically warm see here. There were a few spots in Europe and the US that were below average in temperature, but the entire Earth was hot. Your claim is apparently that your house was cold so therefore the entire Earth was cold. That is not correct. Please provide data to support your wild claims that it was cold and that AGW does not predict more snow in a warming world. -
Eric the Red at 01:31 AM on 19 June 2011How would a Solar Grand Minimum affect global warming?
Albatross, The whole solar / sunspot issue may finally be resolved if a grand minimum occurs. The solar contribution to warming, if any, will be determined, and any more speculation will have ended. I am actually a little excited about this, because we can now study the sun's changes in detail. -
shoyemore at 01:30 AM on 19 June 2011SkS Weekly Digest #3
When I open the site, the lettering (not just in the titles) is screaming at me in bright red capitals. It goes back to normal when I click on a particular post. Am I the only one :) .. or has John decided to "up the temperature"? -
Dan Moutal at 01:28 AM on 19 June 2011SkS Weekly Digest #3
FYI if you need to send a large number of emails and you host is complaining Amazon recently introduced its Simple email service. http://aws.amazon.com/ses/ It is a pain to set up, but seems to work very well once you do so. (At least in my testing of it) And it is fairly cheap. -
Eric the Red at 01:26 AM on 19 June 2011Linking Extreme Weather and Global Warming
Anne-Marie, While global warming theory predicts an increase in rainfall due to increased moisture, that does not correlate with snowfall. Snowfall is largely contralled by temperature; when the temperature rises above freezinf, the precipitation falls as rain. Historical data supports this. The snowiest winters are, on average, the coldest. The past two NH winters were both colder and snowier than the preceding winters. -
newcrusader at 00:51 AM on 19 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
Chris the peak in global temperatures coincides with India colliding with Asia 50 million years ago- The PETM occurred 56 million years ago. See Hansen's book page 153. There was another spike in temperatures about 42 million years ago- not as severe as the PETM. Temperatures and C02 fell for the next several million years until global temperatures reached 3 degrees C above what they where circa 1900. This was about 34.5 million years ago, when C02 fell to 450-500ppm. -
Tom Curtis at 00:32 AM on 19 June 2011Linking Extreme Weather and Global Warming
Norman @34, the point I was trying to make is that there is no point looking for trends in a detrended data set. In this particular case, the trend that was removed was for decreasing rainfall:
The consequence of that has been that while floods in SWWA have almost entirely disappeared, drought has become effectively a permanent condition.
Moving from a situation in which you have either a drouht or a flood every three to five years into a situation in which you have drought in four out of five years represents a decrease in variability in the rainfall (which will show up in a detrended graph), but the drying will not; and itself results in a significant increase in extreme conditions relative to the twentieth century average.
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Eric (skeptic) at 00:10 AM on 19 June 2011Linking Extreme Weather and Global Warming
In the three lower bullets, the first one, increasing trend in extreme rainfall, seems reasonable and well supported although it shows up mostly in local rain gauges. The second bullet seems to contradict the first and the fact that warmer air holds more moisture. This paper http://journals.ametsoc.org/doi/pdf/10.1175/JCLI-3296.1 shows that drought and a reduction in extreme rainfall (as they defined it) went hand-in-hand. The paper also suggests that the particular Australian drought being studied was due to changes in weather patterns, specifically "This supports the argument that the winter (extreme daily) rainfall decline over SWWA is, at least in part, associated with the upward trend of the Antarctic Oscillation." -
Bob Lacatena at 23:51 PM on 18 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
jerryd, Two probably bizarre questions, but: 1) Is it possible that carbon existed in some form prior to the PETM which we no longer see in noticeable quantities today? That is, could there have been some sort of release mechanism which entirely escapes our imagination, exactly because it all "let loose" during the PETM? I have no idea what such a form would be, although I imagine such insights would come from a study of the biosphere in any of the millions of years prior to the PETM (e.g. could a massive die off of plant matter during a previous extinction, combined with a certain predominant climate [dry, wet, hot, cold] have produced a "high layer" of what amounts to fossil fuels, something like peat, but with different properties from peat, and yet more accessible than the coal and petroleum with which we are familiar)? 2) Has anyone ever done a sort of "carbon accounting through the ages" to try to add up and track how much carbon has entered the system at various stages of the earth's existence, and in what quantities in what forms it has existed in the various stages of the earth's existence (atmosphere, living biosphere, decaying plant matter, various sequestered carbon forms, etc.)? -
Ken Lambert at 23:16 PM on 18 June 2011Speaking science to climate policy
Michael Sweet #19 I am not confused at all. Thermal inertia has everything to do with heat flow and temperature distribution. -
Ken Lambert at 23:04 PM on 18 June 2011Speaking science to climate policy
Michael Sweet #21 "If Hansen's estimate of 1.3 W/m2 is correct we are in for a world of pain." Hansen has upped the aerosol cooling estimate as one of the factors to explain the reduced theoretical warming imbalance ie. 0.9 down to 0.59W/sq.m. I don't recall seeing anything in his paper about raising the warming forcings for CO2GHG which should theroetically be about 1.77W/sq.m for a 390ppmv concentration. Why would this forbode a 'world of pain'? -
chris at 22:39 PM on 18 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
newcrusader at 19:15 PM on 18 June, 2011 I wonder whether Dr. Hansen was referring to the raised atmospheric [CO2] levels throughout the Early/Mid Cenozoic (65 MYA to around 40 MYA) onto which the PETM "piggybacked" around 55.5 MYA. There is a very nice theory that this was indeed the result of the remorseless drifting of the Indian subcontinent (to be!) into sub-Asia and the subduction of carbonate-loaded plate beneath the ever-narrowing Tethys sea. The carbonates were driven off as CO2, maintaining a steady high level of [CO2] during this period and warm earth conditions. Once India had "squeezed out" the Tethys sea (around 50 MYA), the "CO2 factory" ceased and was overtaken by enhanced weathering of the Deccan Traps (formed near the end-Cretaceous) as these moved (with the Indian sub-continent) into the warm moist tropical humid belt where basalt weathering was very efficient. By around 33 MYA atmospheric [CO2] thresholds had dropped towards the threshold that allowed polar continental ice sheet formation... Can't find a downloadable version of this fascinating paper: D. V. Kent and G. Muttoni (2008) Equatorial convergence of India and early Cenozoic climate trends PNAS 105:16065-16070 abstract However there is a “Commentary” accompanying their article that summarises their proposal quite nicely here. -
Anne-Marie Blackburn at 22:12 PM on 18 June 2011Linking Extreme Weather and Global Warming
NormanThe claim is that there is 4% more moisture in the air (and this has a very high uncertainty factor and needs above and beyond proof as that moisture is entering and living the air at highly variable rates at any given period). The mountain ranges in US received well above 100% of their normal snowfall. If it would have been 104% then the claim that excessive snow is the result of a small increase in overal moisture levels in the air. When the snowfall is doubled it seems a far stretch that these events can be caused by that slight moisture increase.
That is not what the article claims. Global warming does not cause extreme weather events, but it increases the odds that such events will take place because of changes in the water cycle (and atmospheric circulation) brought on by rising sea and air temperatures. -
Dikran Marsupial at 22:03 PM on 18 June 2011Phil Jones - Warming Since 1995 is now Statistically Significant
MoreCarbonOK So to summarise: All of the professional scientists at NOAA, NASA GISS, UK Met Office, CRU, RSS, UAH (who have relevant qualifications and have studied the data in depth) are wrong and you (who apparently does science as a hobby) are right. If there is a discrepancy in the data, it is at BoM (who collect and distribute the data) not at one of their clients. You apparently have nothing to learn from us (as you have not engaged with any of the constructive criticism so far), but we (in our ignorance) have everything to learn from you. Do you realise how you come across? Do you think anyone will take your analysis seriously having seen your display of hubris here? Most physics departments from time to time have a member of public come along with a proof that Einstein was wrong, or a prototype for a perpetual motion machine, or maths department have someone claim to have a short proof for Fermat's last theorem, or a proof that Godel was wrong etc. You are heading into that territory, please do yourself a favour, doing science as a hobby is something very admirable, but you do need to learn the basics first, and have some humility. -
chris at 21:56 PM on 18 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
jerryd at 20:33 PM on 18 June, 2011 Yes that was the point I was making with respect to okatiniko's suggestion (his post #11) that the raised atmospheric [CO2] in the PETM might be a response to raised temperatures (by analogy with the raised atmospheric [CO2] during glacial-interglacial cycles). The numbers (massive amount of raised [CO2] during PETM and the delta 13C excursion) simply rule out that as a significant contribution. The carbon must have come from "without" the exogenic carbon cycle! P.S. By "exogenic carbon cycle" I assume that you mean the "accessible" carbon within the carbon cycle that involves the carbon in the atmosphere, oceans and living things. -
Norman at 21:40 PM on 18 June 2011Linking Extreme Weather and Global Warming
28 Tom Curtis The graph you describe in your post is the one I am talking about. Extreme events would be excessive or much lower than normal rainfall. In the early part of the graph there were such extremes, then it seems to settle down for awhile and then extremes show up. Is there a trend in the frequency of the extreme events? Looks like there is not enough data available to make such a claim. A longer time frame is required for such. -
Norman at 21:37 PM on 18 June 2011Linking Extreme Weather and Global Warming
#32 JMurphy Mechanisms would help. The claim is that there is 4% more moisture in the air (and this has a very high uncertainty factor and needs above and beyond proof as that moisture is entering and living the air at highly variable rates at any given period). The mountain ranges in US received well above 100% of their normal snowfall. If it would have been 104% then the claim that excessive snow is the result of a small increase in overal moisture levels in the air. When the snowfall is doubled it seems a far stretch that these events can be caused by that slight moisture increase. On Evolution, the evidence is not just in the fossil record. That would be meaningless without the other factor. There is a mechanism for evolution that makes it a valid theory (but still not fact). That mechanism is that DNA is flexible, it can be changed by external forces. If it was a very stable molecule that was higly resistant to change than a mechanism would not exist and another explanation would be required to explain the fossil evidence. In science one makes claims then they propose mechanisms that can explain these claims. -
Rob Painting at 21:37 PM on 18 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
Jerryd - thanks for the input. Very much appreciated. I noticed in Zeebe 2009, of which you were one of the co-authors, a mention of trace greenhouses gases in the concluding remarks. Have you read Beerling 2011? Any comments? -
JMurphy at 21:20 PM on 18 June 2011Linking Extreme Weather and Global Warming
Norman wrote : "Until you have the complete evidence to state the case it is unscientific to make the claims of certainty and mostly seems propoganda to get uninterested people interested in this issue." Maybe you could provide the criteria that would convince you that Global Warming is affecting the weather ? What would it take to convince you ? And, as a side-line, what is the "complete evidence" that has convinced you as to the validity of Evolution - that is, if you do accept it ? -
Norman at 21:05 PM on 18 June 2011Linking Extreme Weather and Global Warming
#26 scaddenp Your point is my point. I do not know if waraming is driving the changes in SAM. I brought the article up because it does not make the claim global warming is the cause nor did it claim it was not the cause. It looked for the root known cause. Further research would be needed to see if global warming played a part. I read articles on the web page daily but rarely post. This point is one that I find most unscientific and it prompts me to post. In the above article the quote "How global warming affects weather parameters" should read How global warming may affect weather parameters. Until you have the complete evidence to state the case it is unscientific to make the claims of certainty and mostly seems propoganda to get uninterested people interested in this issue. May be a necessary action if you believe the world is near doom if action is not taken very soon, but it is not a scientific approach. It is a shock the emotional core approach and it is the very thing that is generating such a wave of denial among the average citizen. People have a natural resistence to what seems like emotional manipulation and react negative to it. When all extreme weather events (including very cold and heavy snow events especially without rigorous proof) are linked to global warming the Public becomes skeptical of the claims and turns of the channel. It does not serve your cause well and creates the very wall you are working to bring down. -
jerryd at 20:33 PM on 18 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
To follow with specific points: Chris: This is not the correct way to think about the problem. The glacial-interglacial changes in pCO2 likely involve carbon redistribution within the exogenic carbon cycle; changes in the PETM (and in our future) likely involve carbon inputs and outputs to the exogenic carbon cycle. In any case, all indications are that massive carbon input during the PETM was a response to external forcing. (And this also hits at the root problem because there is no way to explain this with conventional thinking as to how Earth works). Sphaerica and scaddenp: The idea here comes from Svensen et al. (Nature, 2004). They documented, using seismic techniques, thousands of fluid escape structures in the North Atlantic, which appear to have occurred near the onset of the PETM. Thus, they suggested that instrusive sills converted large amounts of organic carbon to methane, which then escaped from the seafloor. It is a very interesting idea and explains several observations; however, it invokes catastrophism (i.e., essentially an equivalent to all the world’s oil, gas and coal were formed and released within <50,000 years). It also fails to explain the other hyperthermal events following the PETM. Newcrusader: With all deference to Dr. Hansen, this idea makes no sense given the timing. The massive carbon injection at the onset of the PETM happened within a maximum of 60,000 years, and probably less. -
Miriam O'Brien (Sou) at 20:28 PM on 18 June 2011Linking Extreme Weather and Global Warming
Camburn @21 said 'Also, the current La Nina was not a strong one, as some have indicated.' I don't know how it rated in your part of the world. This La Nina was extreme in Australia. Many parts of Australia had the wettest summer on record. From the media release from the Bureau of Meteorology: "This most recent La Niña [2010-2011] will go down in the record books as one of the strongest in living memory. It's been nearly 40 years [1975-76] since Australians have witnessed a La Niña event of this intensity," said Dr Watkins. AFAIK global warming is deemed a contributing factor in the amount and intensity of rain here this past few months, amplifying the effects of La Nina. -
Bern at 20:27 PM on 18 June 2011Linking Extreme Weather and Global Warming
michael sweet: I particularly liked this quote from Jeff Masters' article:One thing we can say is that since global ocean temperatures have warmed about 0.6°C (1°F) over the past 40 years, there is more moisture in the air to generate record flooding rains. The near-record warm Gulf of Mexico SSTs this April that led to record Ohio Valley rainfalls and the 100-year $5 billion+ flood on the Mississippi River would have been much harder to realize without global warming.
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jerryd at 19:54 PM on 18 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
The most fundamental problem regarding our understanding of the PETM (and other "hyperthermal" events) is one of carbon mass balance. All evidence consistently points to the idea that at least 2000-3000 Gigatonnes of carbon rapidly entered the exogenic carbon cycle (the combined ocean-atmosphere-biosphere). This is different than during glacial-interglacial cycles, when carbon was being shuttled between the ocean, atmosphere, and biosphere. It is, however, very analogous to what we are doing currently through carbon emissions (and why so many people have become fascinated with the PETM). To conceptualize the differences, I often give students a picture of a nightclub with three rooms: the big dance hall (ocean), a modest bar (biosphere), and a small restroom (atmosphere). As a spectator, there are two general views for checking the flow of people. One is watching people shuffle between the dance hall, the bar and the restroom, and sometimes there are more people at the restroom (this is the cycling of carbon within the exogenic carbon cycle, and how we think of things during glacial-interglacial cycles). The second is watching people enter and leave the nightclub, and sometimes there are more people in the nightclub, and consequently a more crowded dance floor, a packed bar, and longer queues at the restrooom (this is the cycling of carbon to and from the exogenic carbon cycle, and how we think of things during the PETM and in our future). It is easy to understand how and why the nightclub/exogenic carbon cycle is gaining mass at present-day. It’s 22:00 on a Saturday night, the door is open, and we are adding an excess of about 8 Gt C/yr through combustion of coal, oil and natural gas. However, it is not so easy to conceptualize why this happened rapidly in the past. To follow the analogy, albeit somewhat awkwardly, the PETM is a bit like finding the nightclub packed at 13:00 on a Tuesday afternoon. How can massive amounts of carbon suddenly enter the exogenic carbon cycle ~55 million years ago? Numerous explanations for the PETM carbon mass balance problem have been given. At present, only three seem viable -- intrusive volcanism (Svensen et al., Nature, 2004), burning/oxidation of peat (Kurtz et al., Paleoceanography, 2003), dissociation of gas hydrate in marine sediment (Dickens et al., Paleoceanography, 1995). None are compatible with current views for how carbon cycles on Earth’s surface. It really is an interesting puzzle … on multiple levels. On the one hand, there is the obvious tendency to make comparisons between the PETM and future climate predictions. In general, model simulations for a world perturbed by a rapid and massive input of carbon nicely explains many of the observations in sediments spanning the PETM. On the other hand, the models are based on a framework in which the PETM cannot have occurred … but it did. -
MoreCarbonOK at 19:36 PM on 18 June 2011Phil Jones - Warming Since 1995 is now Statistically Significant
You guys are obviously not interested in following the logic of my thinking and investigations as it progressed and still progresses http://www.letterdash.com/HenryP/more-carbon-dioxide-is-ok-ok so what is the point in arguing if you cut everything I say right left and centre. Carry on and stay in your ignorance. -
Tom Curtis at 19:20 PM on 18 June 2011Phil Jones - Warming Since 1995 is now Statistically Significant
MoreCarbonOK @172, having had experience with deniers I expected an accusation of dishonesty against BoM as soon as the data discrepancy was shown. It was for that reason I chose to compare the most recent full month, when the record was most easily checked, and hence for which any "fiddling" with the data. Despite that, you did not disappoint, and made the accusation anyway. Your accusation is, of course, absurd as is the supposed motive. As if their could not be sufficient commercial demand for a weather record at the airport of the capital of Queensland so that BoM needs to fiddle the data. Please note that you have made the accusation based on no evidence beyond the fact that BoM data was inconvenient to you. Further, you have made absolutely no checks on your hypothesis to see if it had any validity. That clearly shows that whatever your hobby is, it is not science. As it is, it is very easy to check if BoM has altered the data by comparing it with other records of the Brisbane Airport data. The first alternate record I could find was Weatherzone. Performing the same checks as I did for Tutieme (first four days and monthly mean for May 2011) I found complete agreement with BoM data. (I could not check humidity as it is not recorded at Weatherzone.) Please note the logic here. If BoM modified the data before initially issuing it, Tutiemo would have the modified data, and hence the modification could not be the explanation of the discrepancy between tutiemo and BoM. If BoM modified the data after first issuing it, then Weatherzone, who keeps a daily record, would have the unmodified data and would not agree with BoM. Hence this is simply a case of tutiemo getting the data wrong. I request that the moderator leave your post, even though it clearly violates the comments policy, and the replies on this thread. In that way your intellectual integrity will be clearly advertised to anyone tempted to take your website seriously. -
newcrusader at 19:15 PM on 18 June 2011CO2 Currently Rising Faster Than The PETM Extinction Event
Dr. Hansen feels that C02 was released from rich carbon beds in what is now the Indian Ocean during the PETM. India was still not attached to the Asian continent- and was moving rapidly through this ocean before its collision with the Asian continent. This carbon rich area was an area where many rivers emptied their debris. At least that is how Dr. Hansen perceives the PETM from a paleo climate and geological perspective in his book 'Storms of my Grandchildren'. Once India collided with Asia, C02 levels began to drop. -
Tom Curtis at 18:45 PM on 18 June 2011Linking Extreme Weather and Global Warming
Norman @25, do you mean to ask whether we see a trend in the graph of the detrended rainfall anomaly for south west Western Australia (Fig 1 b)? Well, no I don't see any trend in the detrended data, and nor would I expect to. Of course, if figure 1 b is not the figure you are referring to, would you please be more specific as I do not see any other suitable candidate. -
michael sweet at 18:41 PM on 18 June 2011Linking Extreme Weather and Global Warming
Jeff Masters wonder blog has a detailed article about the weather in the USA this spring. "Nature's fury reached new extremes in the U.S. during the spring of 2011, as a punishing series of billion-dollar disasters brought the greatest flood in recorded history to the Lower Mississippi River, an astonishingly deadly tornado season, the worst drought in Texas history, and the worst fire season in recorded history. There's never been a spring this extreme for combined wet and dry extremes in the U.S. since record keeping began over a century ago, It was the most extreme spring on record" (117 years). It was probably just the La Nina, worst in 117 years. -
Dikran Marsupial at 17:38 PM on 18 June 2011Phil Jones - Warming Since 1995 is now Statistically Significant
MoreCarbonOK I am not going to moderate your post as I am taking an active part in the discussion, but your post contains an accusation of dishonesty, which is explicitly forbidden by the comments policy. If you don't want your posts deleted by the moderators, please conform to the comments policy. BTW, your post only reduces your credibility further as yet again you are demonstrating a complete lack of self-skepticism. There is no good reason to think Tuitempo has the correct data and BoM data is incorrect. There will be a lot of organisations that downloaded the data from BoM at the same time or before Tuitempo, so if BoM were fiddling the data there would be no way they could get away with it. The guys at BoM are not stupid and wouldn't try fiddiling with data when there was no chance of getting away with it, even if there were something to gain from it (which there isn't, the data are primarily collected for weather forecasting, not climate studies, so they would be funded to collect it anyway). -
Dikran Marsupial at 17:26 PM on 18 June 2011Phil Jones - Warming Since 1995 is now Statistically Significant
sphaerica I shouldn't worry, the attitude to constructive criticism he has displayed here means it probably hasn't been much of an advertisement. His credibility is rather lower now than when he made his first post here; but it was his choice to behave in the rather unscientific way he did. -
Philippe Chantreau at 16:37 PM on 18 June 2011Increasing CO2 has little to no effect
Actually Scaddenp, CH4 is 24 times more powerful than a CO2 as a GHG, on a per molecule basis. However, the total amount of CH4 in the atmosphere is nowhere near that of CO2. This has been discussed already and is also treated on RC. Truly interested readers should become proficient at using search engines on both sites. -
scaddenp at 16:37 PM on 18 June 2011Linking Extreme Weather and Global Warming
Norman, why are you so sure that the proximate causes of precipation change does not have warming as the ultimate cause. What drives the changes in SAM? -
Norman at 16:08 PM on 18 June 2011Linking Extreme Weather and Global Warming
Albatross, You like the peer-review format. Here is a peer-reviewed article that shows the precipitation of Southwest Western Australia since the 1970's to present. If you look at the graph of precipitation over this time period, please explain how you see a trend and the trend is more extreme? I do not see it but maybe I need glasses. Article on causes of precipitation variations in Australia. -
Norman at 15:54 PM on 18 June 2011Linking Extreme Weather and Global Warming
Here is a peer-reviewed article that explains changes in New Zealand precipitation without the need for global warming as a cause. Likely causes of changes in New Zealand precipitation. -
Bern at 15:26 PM on 18 June 2011Linking Extreme Weather and Global Warming
Speaking of extreme weather - I was just looking at the IJIS sea ice extent graph. Sea ice seems to be declining at a similar rate to the record-setting 2007 season - but is currently nearly a million km2 lower. Will be interesting to see how the arctic weather patterns develop this northern summer, as that's what will determine the minimum extent in September. If we get more relatively abnormal weather, with cold arctic air pushing south and warm temperate air pushing north (as has happened a few times in recent years), we could be looking at some very cool summer weather in some spots, and record warm weather in some northerly locations. On the other hand, we might see some more 'average' weather (notwithstanding that the NOAA climate 'normals' have increased by 0.5-2ºC over most of the USA, thanks to dropping off the 70s and adding in the 2000s).
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