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Comments 131351 to 131400:

131351. Philippe Chantreau at 11:49 AM on 25 September 2007
        It's the sun
        What it also shows for the 20th century is that the timing is not quite right. Temp increases sharply before the TSI and then, even before the TSI reaches its first 20th century spike, the temp actually starts to decrease, followed by a TSI decrease, and then the temp increases again, followed again (very modestly) by the TSI. If I was using a skeptical aproach to attempt a correlation between the 2 on this graph, it would appear that TSI was driven by temperature during the 20th century.
131352. Philippe Chantreau at 11:31 AM on 25 September 2007
        Jupiter is warming
        Interesting paper. I don't have a subscription so I could not read the full article. I might miss something but from the abstract and the excerpt provided I do not see where it is demonstrated that heat from solar particle winds (?) warms up the polar regions. Any cites on how the particles would generate the heat? Whatever heat is there is unlikely (that's an understatement) to amount to more than the solar irradiance itself, which is, as we have well reviewed, 2.4 times less than the internal heat. I have not read anything suggesting that internal heat is confined to the equatorial regions. Although the lower latitudes Jovian auroras are somewhat mysterious, the polar ones are mostly similar in nature to those of Earth, as suggested by the Cassini/Galileo data: http://www.jpl.nasa.gov/releases/2002/release_2002_46.html I don't know of any research attributing a significant part to auroras in the atmospheric heat budget of any planet and I still have not burned my hand by touching a neon tube. If there is some research about that, a cite would be nice. From my (modest) recollection of physics, I would think that trying to heat anything with particles is like trying to boil a kettle by throwing hot pebbles at it. Eventually you may succeed with a super-dense barrage of particles, but that's not what the solar wind is.
        Response: Phillipe, for the record, free registration to the Science website will get you access to that article. Science has a window of free access (providing you're registered) - the only articles requiring subscription are recent ones and much older papers but 2004 is fair game.
131353. papertiger at 05:09 AM on 25 September 2007
        Jupiter is warming
        Let's return to the main thrust of your post. You say "Temperature is relatively uniform on Jupiter - the temperature at the poles is nearly the same as at the equator. This is due to the chaotic mixing of heat and airflow from vortices (eg - the White Ovals). The oscillatory motions of the White Ovals ceased after they merged, dampening the movement of heat from Jupiter's equator to its south pole." This is all falsified by observation of the Shoemaker Levi 9 comet aftermath. When the comet hit it created certain shock chemicals which were tracked over the years by Galileo's CIRS; hydrogen cyanide (HCN), carbon monoxide (CO), and carbon monosulfide (CS). The HCN is long lived and provides a footprint to study latitudinal transport. From the paper Jupiter's Atmospheric Composition from the Cassini Thermal Infrared Spectroscopy Experiment -

        HCN latitudinal distribution. Once produced by shock chemistry during the SL9 impacts, HCN is stable and almost inert in the stratosphere, so that it is a tracer of atmospheric motions. In fact, the peak abundance is still at the impact latitude [emphasis is mine], and the total HCN mass in Jupiter's stratosphere observed between 1995 and 2000 is comparable to what was inferred right after the SL9 impacts in 1994. The sharp falloff of HCN observed at high latitudes cannot be due to chemistry driven by particle bombardment in the auroral regions. Ion chemistry does not break the CN bond but only efficiently recycles HCN. Thus, a dynamical explanation is the most logical explanation, and HCN should provide a powerful constraint on mixing at mid-latitudes in the southern hemisphere by meridional winds and horizontal wave-induced diffusion. The CIRS observations yield a maximum 5° latitudinal shift in the location of peak abundance from the impact latitude, a behavior consistent with a meridional velocity of zero and a spreading due to diffusion. The equatorward spread of HCN is then mostly by diffusive transport. If horizontal diffusion were constant with latitude, the SL9-produced HCN would maximize at the south pole. The most probable dynamical reason for the southward decrease is the inhibition of wave-induced diffusive mixing of HCN in the presence of strong circumpolar winds (vortices) in Jupiter's polar regions. This effect is analogous to the polar vortex that produces a confinement vessel for the Antarctic ozone hole from mid-latitude air in Earth's stratosphere and dynamically isolates polar regions from lower latitudes. Latitudinal temperature gradients measured by CIRS in Jupiter's upper stratosphere indicate the existence of strong polar vortices near 65°N and 65°S, yielding jet streams with eastward velocities of about 20 m s–1 or higher near 1 mbar. Ground-based observations at the Infrared Telescope Facility confirm the presence of a north polar vortex.

        So you can see that there was no appreciable latitudinal heat transport for Red Jr. to interrupt. Also this paper proves that Jupiter's polar regions are heated by solar wind particles accelerated to relativistic energy level by the magnetic flux, rather then heat mixing from the equatorial region.
        Response:

        There are actually "5 thrusts" to my post, any one of which puts paid to the idea that climate change on Jupiter is due to a warming sun:

        1. Jupiter's storms are fueled internally, not by the sun
        2. The changes occuring (eg - disappearance of vortices, creation of Red Spot Jr) are the result of internal turbulence, not an external forcing
        3. Global warming isn't happening on Jupiter - it's a change in the distribution of energy with more in the equator, less in the poles due to disappearing vortices
           
        4. The climate change cited by skeptics (changes of 10 degrees) haven't even been observed yet - they are model predictions
           
        5. The sun isn't getting hotter
           

        However, I appreciate your tenacity and hard work in researching Jovian climate - the comments have been engrossing and John Cross will be chuffed to find a paper on the impact of Shoemaker Levi as that was what got me started on Jupiter in the first place.
131354. Philippe Chantreau at 01:54 AM on 25 September 2007
        Other planets are warming
        Rereading through Papertiger posts, I thought it would be interesting to address the issue of water on Jupiter. Here is what I found in 10 minutes of straight, basic googling. Observations by the Galileo probe in orbit around the planet led to more information on this subject than the atmospheric probe, which entered over a very dry, cloudless area. This release gives the skinny: http://www.nature.com/nature/journal/v446/n7136/abs/nature05718.html Here is also a cool pic from JPL: http://pds.jpl.nasa.gov/planets/captions/jupiter/watercld.htm I had conversations with proponents of outer SS planetary warming before and for some reason, they seem to be fond of Dr Beebe. She contributed to this paper: http://www.aas.org/publications/baas/v31n4/dps99/212.htm. Overall, it does not seem that Jupiter suffers a lack of water such as to invalidate the convective models proposed by Gierasch and many (most) others.
131355. Philippe Chantreau at 02:55 AM on 24 September 2007
        Mars is warming
        This seems to be the best work so far on Mars' recent weather: Global warming and climate forcing by recent albedo changes on Mars
        Response: Thanks, this was the study I was refering to but I didn't have a direct link to the study. I've updated the page with the link added.
131356. Philippe Chantreau at 02:36 AM on 24 September 2007
        Mars is warming
        Once again, it is useful to ask ourselves this question about other planets: how unusual is this (the recent southern ice caps sublimation)? This link gives a hint: http://www.msss.com/http/ps/seasons/seasons.html. Consider also that Mars' orbit takes about 589 days, letting us observe only three full seasonal cycles in 5 years. It has long been known that Milankovitch cycles are the best fit to the available evidence for historic glaciation-deglaciation cycles on Earth. The energy source, the Sun, is extra-terrestrial but there is no evidence that it got brighter or dimmer in proportions apt at changing our climate and in any case, that is not what Milankovitch cycles are. As far as I can recall, the energy received changes because of the planet getting closer, farther, or being oriented slightly different, which is a function of its orbit and precession; in that sense, extra-terrestrial is a little misleading, since these qualities could really be called intrinsic to the planet. The point of the paper cited by papertiger is that Earth and Mars' Milankovitch Cycles could be resonant. I wonder if anyone has tried to obtain some level of confirmation from pure celestial mechanics calculation. In any case, it is interesting but quite irrelevant to the current terrestrial warming, which does not correlate well with neither Milankovitch nor with the so-called Martian warming. That Martian warming is really a re-warming back to the kind of weather seen by the Viking crafts, and the Earth should now be heading for cooler climate if only Milankovitch was at play.
131357. biocab at 13:46 PM on 22 September 2007
        It's the sun
        No, what it shows is that the solar irradiance in 2006 was 1367.25 W/m^2.
131358. biocab at 01:44 AM on 22 September 2007
        It's the sun
        Ben Lankamp, the source is http://lasp.colorado.edu/science/solar_influence/index.htm It's not unrealistic given that the data is NH instrumental. Solar irradiance is going up, not down. You cannot take just one sunspots cycle out of context. The last would be pseusoscience.
        Response: The only information at the LASP page about long term trends in solar irradiance is the following graph:

        

        What it shows is a close correlation between Solar Irradiance (the orange line) and global temperature (dotted blue line). But they also show the correlation ends when the modern global warming trend begins in the mid-70's. The data is all there and it's unambiguous - there's a reason why so many studies (listed above under "Other Studies on solar influence on climate") conclude the sun's influence on recent global warming is minimal.
131359. Philippe Chantreau at 03:00 AM on 21 September 2007
        It's the sun
        I like your analysis Ben. If you haven't, check Tamino's post "PMOD vs ACRIM." He did an outstanding job of examining solar data. Hope John isn't going to get tired of me always referring to other sites!
        Response: Not at all - the point of Skeptical Science is to point people to relevant resources, primarily the peer reviewed papers but good blog posts too. Tamino has two great posts which I link to from my Is the sun getting hotter? page (and I even lifted one of his graphs to use on my page).
131360. Philippe Chantreau at 16:10 PM on 20 September 2007
        Other planets are warming
        What "local" climate statistics do you use to justify the assertion that Saturn or any other outer SS planet is undergoing climate change? The IPCC definition of climate for Earth involves a 30 years period. I'm sure you know what kind of time period that translates into for Jupiter, Saturn, Uranus, Neptune or Pluto (respectively 356, 884, 2522, 4947 and 7435 years, give or take). I find interesting that "skeptics" so eagerly recommend taking the enormous amount of highly accurate data available for Earth with a grain of salt (or the all shaker for that matter), while at the same time accepting wild conclusions on poorly understood extra-terrestrial "climates" based on very scant, spotty observations. If you want to tell me about climate change on outer SS planets, I'll take the skeptical approach and ask for some serious climate history and data before considering any conclusion. As for Pluto's expanding atmosphere observation, it was made under ideal conditions, with equipment never available before (KECK, if I remember right). So, even if the event witnessed on that occasion is a regular occurrence, it could never have been seen before, for that reason and this other detail: with a year lasting close to 248 Earth years, Pluto has not been observed through a full orbit yet. Should we add that Pluto's atmospheric changes are suspected to be highly albedo dependent and that Pluto has been darkening since the 50's (collection of space materials is probable)? There are countless caveats and like considerations for all the planets supposedly experiencing "climate change." How about crunching some numbers and showing us what kind of energy output would be necessary from the Sun to obtain those changes that you assert are Sun driven? Then we could compare that with the observed changes in solar irradiance. You could crunch some more and come up with theoretical values of increased energy input for Venus and compare with what is actually happening there (not much unusual if I recall), where the Sun is mighty close. Jupiter deserves some crunching too: three vortices merged into one to form the so-called Red spot Jr. How unusual is this? By the way, the idea of Jovian internal heat is not new, see this: But Galileo certainly helped restart the debate, as discussed here: http://www.nasa.gov/home/hqnews/1996/96-103.txt I noted the following passage: " According to mission scientists, Galileo probe data strongly suggest that circulation patterns in Jupiter's cloud tops and its interior (which runs 10,000 miles deep) are part of one continuous process. Dr. David Atkinson of the University of Idaho continues to report persistent Jovian wind velocities of over 400 mph. The probe detected no reduction in wind speed, even at its deepest levels of measurement,approximately 100 miles below Jupiter's clouds. Galileo scientists regard this finding as confirmation that the main driving force of Jupiter's winds is internal heat radiating upward from the planet's deep interior. The strength of the Jovian winds and the fact that they do not subside with depth is very significant, according to Dr. Andrew Ingersoll of the California Institute of Technology, Pasadena, CA." This blurb is interesting also: http://www.jhu.edu/~gazette/julsep96/sep0996/model.html Closer to Earth: for all the talk about Mars, it is worth pointing that it went trough significant cooling after the Viking landing, before experiencing the more recent warming some are so excited about (which is best explained by dust storm patterns). It does not leave that much correlation with Earth changes. The bottom line is this: what is presented as climate change carries little meaning when the climates in question are so poorly known to start with. Outer SS planets are exposed to all sorts of influences that have as much weight as the solar constant in their "climate." Attempts to show a solar source to terrestrial climate change by pointing to observations on other planets whose significance is unclear should be received with the highest skepticism. Especially when there are satellite observations of solar irradiance available for Earth. Sorry for the long post.
131361. papertiger at 04:49 AM on 20 September 2007
        Other planets are warming
        Uranus has just passed into the equinox of its orbit where the whole of the planet is receiving sunshine evenly, as opposed to just the one pole getting continuous sunlight. So of course it is going to cool down on the poles. By the way, you left out Saturn and Enceladus on your list of planets or moons undergoing climate change.
131362. papertiger at 04:42 AM on 20 September 2007
        Other planets are warming
        I have heard discussion about ammonia clouds (being imaged for the first time and such). What is the conductivity of ammonia as compared to water? As I remember it, water is only a conductor due to impurities. Ingersol and company "infer" water deep under the opaque cloud cover, beyond direct inspected, due to lightening strikes. Is it not possible that some other chemical is the source of lightening activity on Jupiter? There were two events which allowed the direct examination of whether Jupiter's atmosphere contained appreciable ammounts of water. The Galileo atmospheric probe, which found no water, and the Shoemaker Levi comet crash. In the first instance, Ingersol explained the lack of water found by the probe as due to it falling in an area analogous to a desert region on Jupiter. IN the second case, the comet, due to it's disintigration, fell over a wide area of Jupiter. Spectroscopic analysis found some water but it wasn't native to the planet. The water vapor found was carried by the comet and after a short period of time was converted through photolytic processes into Co2.
131363. Philippe Chantreau at 07:46 AM on 19 September 2007
        Temp record is unreliable
        Obviously, it is beyond unthinkable at CA that the evidence pre-existing their "scrutiny" could have any validity. Let us not forget what exactly the CA/McIntyre effort basic drive consists of, in summary: we do not like what the scientific research concludes on this issue, so we are going to review every single detail, fishing for anything that could lead in the direction that we favor. On the other hand, the actual climate research follows this basic process: study climate, by considering the physical laws governing atmospheric dynamics and their interrelations, by modeling these on supercomputers, by gathering as much data as can be obtained and carefully sorting through and analyzing that data. It is not very suprising that when the CA folks actually get into a scientific way to analyze data, their conclusions confirm the prior ones from real researchers.
131364. Philippe Chantreau at 08:54 AM on 18 September 2007
        Temp record is unreliable
        John V on CA has results using "good" stations and "bad" stations (per Watts definitions) and comes to results extremely close to GISSTEMP. GISSTEMP is closest to the curve obtained withe the "good" stations. There is a post and a link on Rabett Run, you can also go directly to CA.
        Response: Phillipe, thanks for the comment. You can find Rabett's post here plus here's a direct link to John V's graphs on Climate Audit. What I find particularly interesting is Steve McIntyre's response:

        "...keep in mind that USHCN stations have already passed one cut of quality control. They are represented as “high quality” stations. No such representations have been made for stations in China - they may be good, they may be bad, they may have had accurate records throughout the turmoil of Chinese history, they may not. I don’t know how you’d even begin to place “confidence” in the Chinese record in the absence of such analysis."

        Eg - he concedes that in spite of all those photos of air conditioners and car parks, the US stations are actually good quality. So instead, let's go pick on China instead!
131365. John Cross at 01:30 AM on 18 September 2007
        Jupiter is warming
        Papertiger: Interesting idea about the tides on the sun, but I am not sure it is as large as you might think. I took the following quote from PLANETARY TIDES AND SUNSPOT CYCLES by Condon and Schmidt (Solar Physics 42, 1975) "Thus the maximum tide height produced by the Earth is only Hme = 0.1 mm. The tide due to Mercury is comparable, and those caused by Venus and Jupiter are about twice as large. The tidal effects of all the remaining planets are much smaller." John
131366. John Cross at 00:45 AM on 18 September 2007
        Jupiter is warming
        Papertiger. I suspect that you have overlooked the fact that Jupiter is a sphere. My 55 W/m2 value looks at the intensity of solar radiation at Jupiter's radius as opposed to earth's radius. However your 33 W/m2 looks at emissions from the whole of Jupiter. The formula for the surface area of a sphere is 4 pi r2 so we need to divide the 55 W/m2 by 4 to get about 13.75 W/m2. Dividing 33/13.75 gives you 2.4 so I would say the 2.5 value is pretty close. John
131367. Steve Bloom at 06:23 AM on 17 September 2007
        Satellites show no warming in the troposphere
        John, note that Christy (with Spencer) pulled a bait and switch on his CCSP report co-authors after they'd gone to all that trouble avoiding trashing his work in the report. I don't think they were amused. Also FYI, Roy Spencer has become Rush Limbaugh's in-house climatologist.
131368. papertiger at 18:43 PM on 16 September 2007
        Jupiter is warming
        John Cross asks an interesting question. 1) The orbit of Jupiter is somewhat eccentric and at times is 70 million km closer to the sun than other times. Could the your warming be associated with this annual effect? Answer: Jupiter is huge. So huge infact that the focii of orbit between Jove and the sun is actually outside the solar surface. This makes the relationship between the two roughly analogous to the relationship between the Earth and moon. The Moon's gravitation causes tides on Earth. Likewise Jupiters gravitation causes tides on the sun. This solar tide results in a greater surface area photosphere, hence higher insolation on Earth, when Jupiter is in perihelion.
131369. papertiger at 10:23 AM on 16 September 2007
        Mars is warming
        Nice picture of the southern icecap by the way.
        Response: Thanks, it was either a photo of the icecaps or a picture of Fred Thompson. I think I made the right choice.
131370. papertiger at 10:20 AM on 16 September 2007
        Mars is warming
        Sediment cycles on Mars in resonance with Earth

        After computation of the astronomical Milankovitch cycles on deep sea cores for the last 2.4 Ma the same cycles revealed to exist in land sediment series: Long Term (last 2.4 Ma, Pleistocene) and Middle Term (last 127Ka, Last Interglacial - Last Glacial Time-span) Time Series after cycle computation with the newly developed ExSpect method. Moreover, the same calculation method proved useful for Short Term Time Series as well on sediments of the last 10.000 years (10Ka). The latter cycles as those obtained for ice and glacial lake deposits on Mars could also clearly be traced back in the planetary correlations computed by the NASA Goddard Space Flight Center. This points to an extra terrestrial astronomical forcing of the origin of all these cycles on both planets Earth and Mars.

        Which begs the next question - how would they know this without taking a sediment sample on Mars? Answer: they got one with the the Mars orbital satellite.
131371. papertiger at 04:25 AM on 16 September 2007
        Jupiter is warming
        Lets go ahead and quantify, by all means. John Cross has helpfully converted the vague "4% of the level we receive on earth" into the more useful 55 W/m2. On to the internal energy source. This is the tricky part. How much "heat" is Jupiter giving off? I have seen rather vague discriptions, with qualifiers such as "almost" and "about", but no concrete numbers. Before Pioneer visited, the heat given off of Jupiter was estimated as "several" times the incident sunlight. After Voyager it was "about" 2 and 1/2 times. Now the author of this post has lited on "almost" twice as much. No help here, so I went to the library. In Reta Beebe's book Jupiter: The Giant Planet page 72, we learn from Rudolf Hanel and his team at Goddard, who developed the duel instrument radiometer and Michelson interferometer used by the Voyager spacecraft, that

        By comparing the intensity of the infrared light that was obtained during daylight and dark intervals, Hanel and his team could separate scattered infrared sunlight from infrared radiation that was emerging from below the clouds. They show that Jupiter emitted energy at a rate of 0.0033 W/cm2.

        Well dang. Something doesn't compute. How is 0.0033 W/cm2 "almost twice as much" as 55 W/m2? Someone explain this to me, because I am stumped.
        Response: John Cross' later comment addresses this but let me clarify a few things. Firstly, your figures are correct. Jupiter emits energy at 0.0033 W/cm². As there are 10,000 square centimetres in a square metre (eg - 100cm x 100cm), this means 0.0033 W/cm² = 10,000 x 0.0033 W/m² = 33 W/m². The surface area of a sphere is 4 x pi x r². So the total amount of energy emitted by Jupiter = 33 x 4 x pi x r² Watts = 414 r² Watts (I can't be bothered looking up Jupiter's radius).
        
        Secondly, the solar flux at Jupiter is roughly 55 W/m². But Jupiter only absorbs solar energy on the half of the planet facing the sun. Eg - the area that absorbs solar energy at 55 W/m² is a circle with the same radius as Jupiter. The area of a circle = pi x r². Hence, the total amount of solar energy absorbed by Jupiter = 55 x pi x r² Watts = 172 r² Watts .

         

        In other words, Jupiter emits about 2.4 times as much energy as it absorbs from the sun. Thanks for your research in quantifying the incoming and outgoing radiation. I've updated the text from "almost twice as much" to "more than twice as much".
131372. papertiger at 03:23 AM on 16 September 2007
        Other planets are warming
        Phil, Here is the first two sentences from Gierasch

        "The energy source driving Jupiter's active meteorology is not understood. There are two main candidates: a poorly understood internal heat source and sunlight."

        Doesn't sound like he has extensively analyzed the Jovian storms to me. Further on he says,

        We estimate that the total vertical transport of heat by storms like the one observed here is of the same order as the planet's internal heat source. We therefore conclude that moist convection-similar to large clusters of thunderstorm cells on the Earth-is a dominant factor in converting heat flow into kinetic energy in the jovian atmosphere.

        Now isn't it interesting that when in doubt Gierasch offers up water vapor as his main transport of heat energy on a planet without water. Recall it is the water born heat exchange which is not well modeled, misunderstood, discounted, and ignored by the IPCC on Earth as the basis for alarm, regarding CO2 warming. Does this not disturb you?
        Response: I think the point of the "is not understood" is that his paper sheds some light on Jupiter's meteorology. Also, there is water on Jupiter. Ingersoll 2000 says "We estimate, based on the inferred abundance of water in the deep atmosphere that the base of the water cloud is at 6 bars. From the base to the top of the cloud clusters the vertical distance is 80 km, or 0.1% of Jupiter's radius. Water is the principal agent of cloud electrication, as the other condensates are thought to be less abundant than water."
131373. TMLutas at 05:50 AM on 15 September 2007
        Temp record is unreliable
        I strongly suspect that periodic physical checks are needed to avoid error. Poor ventilation, not painting when needed, allowing vents to get partially or totally blocked, etc. can have a heating effect on these stations independent of UHI. The abortive attempt to hide the station locations and an awful lot of hot air floating around the Internet about how physical checks aren't really necessary makes me think that the universal commitment to quality is more theoretical on some people's part than real.
131374. Philippe Chantreau at 22:39 PM on 14 September 2007
        Jupiter is warming
        Here are a couple more questions: how much increased solar irradiance would it take to "warm" Jupiter in the extent that you propose (and that you haven't quantified)? And how would that same increased irradiance be felt on Earth (where a significant solar irradiance increase has not been detected recently). By the way, the sheer pressure generated by Jupiter's gravity is enough to produce a lot of its internal heat.
131375. Philippe Chantreau at 20:44 PM on 14 September 2007
        Other planets are warming
        Papertiger, your comment about Jupiter is in disagreement with research conducted by Gierasch (summary and comment readable on space.com), and several other teams. Gierasch has extensively analyzed the jovian storms and has concluded that they can not be fueled by solar energy, there is not enough of it. Other teams have built very successful models of Jupiter's atmosphere, they all use internal heat as the energy source. All this has been published and is easy to find. Jupiter's core is extrememly hot, from compression and the residual heat from the planet's formation. That heat is the main driver of the planet's weather and climate.
131376. Ben Lankamp at 06:59 AM on 14 September 2007
        It's the sun
        Small addition: this is what you get when you compare random years, say 1966 and 1996 (thirty years): 1365,951 and 1365,621, a decrease of -0,330 W/m². This is all using the Lean (2000) data from your webpage. Now 1966 was three years away from the maximum of cycle 20 in 1969 and 1996 was the minimum at the end of cycle 22.
131377. Ben Lankamp at 06:42 AM on 14 September 2007
        It's the sun
        What is your source of 1367,25 W/m² for 2006, honestly for me it would seem like an unrealistic jump from the late 1990's to now. According to the PMOD-WRC data (link above, 'direct satellite measurements'), which is consistent with Lean (2000), the average TSI last year was 1365,4 or 1365,5 W/m² which seems more appropriate than 1367 W/m². In any case you cannot directly compare 1957 with 2006 because 2006 was the 11-year cycle minimum and 1957 was a cycle maximum, so compare maxima or minima or averages per solar cycle instead. E.g. if I use the Lean (2000) data from your webpage and compare 1957 with 2000 (maximum of solar cycles 19 and 23), I get 1366,681 and 1366,724, which equates to deltaF = 0,043 W/m² or a deltaT of 0,06 according to your equation. The first half of the century however I see a deltaF of 1,6 W/m² in the maxima and deltaF of 1,0 W/m² in the minima, equating to deltaT = 1,6-2,4 degrees. This strikes me more as a debate on data than principals or methods, by the way. The detrended data shows no [significant] decrease or increase in TSI/ISI. From that perspective I neither agree with the Lockwood article that ISI has decreased in the last 25 years nor with the claim that it has increased in the last 50 years. I would have to make myself more familiar with the exact fundamentals of radiative forcing before investigating whether or not the trend found would induce any (significant) forcing, your equation looks nice but I want to check it for myself first :-). On CO2 forcing: climate sensitivity to doubling of its concentration has a probability range even in the IPCC reports, however further discussion on this is not meant for this page.
131378. John Cross at 05:52 AM on 14 September 2007
        Jupiter is warming
        Paper Tiger: I found your link interesting but I do not see the connection with what seems to be your premise that the climate change is caused by an increase in solar radiation. As John Cook pointed out there is a great deal of internal heat, you can argue about its source but not the fact that it is there. Also as John pointed out the energy received by Jupiter from the sun is 1/25 the amount that earth receives. Taking a typical value of 1365 W/m2, that means that Jupiter gets about 55 W/m2. This of course also means that the changes in solar values are 1/25 that of what we see on earth. Taking some typical ACRIM values for the solar output during solar cycles we see a difference of 3 W/m2. In jupiter terms this would be a change of 0.12 W/m2. Much less than current enhanced CO2 forcings on Earth. Can this be responsible for warming Jupiter. Now, in the tradition of science, let me ask you some questions, specifically how can you exclude the following. 1) The orbit of Jupiter is somewhat eccentric and at times is 70 million km closer to the sun than other times. Could the your warming be associated with this annual effect? 2) What was the effect of Shoemaker-Levy 9 on the planet and can you state that we are not seeing residual effects from that? Finally, based on the above, what would allow you state that the warming is caused by solar output (especially since we haven't seen any increase in solar ouput on Earth)? My take on this is that we don't really know what cause the climate to change on Jupiter so it can not be taken as evidence of increased solar output. Regards, John
131379. biocab at 05:13 AM on 14 September 2007
        It's the sun
        Well, let's compare 1957 (50 years ago) with 2006 (one year ago). In 1957 the ISI was 1365.7689 W/m^2, while in 2006 the ISI was 1367.25 W/m^2. Where is the decrease? The radiative forcing from ISI is 0.85 K per each W/m^2 of solar IR. From 1957 the extent of ISI has been 1.4811 W/m^2, that is 1.26 K. It is more credible than the 0.02 K from the heat absorbed by the CO2. The point where I don't agree with you is the radiative forcing for CO2, which is not 5.35 W/m^2, but 0.414 W/m^2. That was considered in the NAS paper. It seems, from the article, that the value for deltaF wasarbitrarly fixed.
131380. papertiger at 03:09 AM on 14 September 2007
        Jupiter is warming
        Here is something that I found striking in it's implication for climate change in the Jupiter system.

        Although astronomers had studied Jupiter from Earth for several centuries, scientists were surprised by many of Voyager 1 and 2's findings. They now understand that important physical, geological, and atmospheric processes go on - in the planet, its satellites, and magnetosphere - that were new to observers. Discovery of active volcanism on the satellite Io was probably the greatest surprise. It was the first time active volcanoes had been seen on another body in the solar system. It appears that activity on Io affects the entire Jovian system. Io appears to be the primary source of matter that pervades the Jovian magnetosphere -- the region of space that surrounds the planet, primarily influenced by the planet's strong magnetic field. Sulfur, oxygen, and sodium, apparently erupted by Io's volcanoes and sputtered off the surface by impact of high-energy particles, were detected at the outer edge of the magnetosphere. Particles of the same material are present inside Io's orbit, where they accelerate to more than 10 percent of the speed of light. It is clear to scientists from a comparison of data from Pioneers 10 and 11 (which flew past Jupiter in late 1973 and 1974) and the Voyagers that something changed in the four and one-half years between the Pioneer and Voyager encounters. It is not entirely clear just how far-reaching those changes are, or what brought them about. They may be related to Ionian activity. It is difficult to imagine, however, that at least some of Io's volcanoes were not erupting when the Pioneers flew past; it is also, the Voyager scientists say, difficult to believe the Pioneers' instruments failed to see magnetospheric concentrations of sulfur detected by both Voyager spacecraft (Voyager 1 saw greater concentrations than Voyager 2).

        Excerpted from Voyager Jupiter Science Summary May 7, 1990 Courtesy of: Jet Propulsion Laboratory (JPL) weblink Let me encapsulate. In the early 70's, Pioneer's 10 and 11 flew through the magnetic field of Jupiter and detected no sulfuric eruptions or particles that were obvious and pervasive in Jupiter's magnetic field in 1979. In short the climate changed.
131381. papertiger at 01:50 AM on 14 September 2007
        Jupiter is warming
        An internal heat source? That would involve gravitational compression. For a planet undergoing gravitational compression to have a climate change, such as a new Red Jr. or increased heat at the equator, the specific gravity would have to change. Jupiter would have had to gain weight.
        Response: Jupiter's internal heat source is not well understood but has been well observed for several decades (eg - Murphy 1975, Fazio 1976). Gierasch 2000 concludes that moist convection from the internal heat source is the dominant factor in converting heat flow into kinetic energy (eg - internal heat fuels the storms). But it's not changes in the internal heat source that is causing climate change on Jupiter at the moment. The predicted climate changes at the equator and poles are due to changes in the vortices that mix heat throughout the planet. I recommend reading this interview with Philip Marcus who explains the process in detail.
131382. papertiger at 23:03 PM on 13 September 2007
        Other planets are warming
        You realize that the argument, Jupiter is heated from within and only receives a small fraction of the energy from the sun that the Earth does, depends upon that 4% of energy being incapable of driving weather. We know this to be false from your own report regarding Neptune. While Jupiter receives 25 times less energy per square meter from the sun that the Earth does, Neptune receives 900 times less. How is it that the 900 times weaker sunshine can drive weather and promote seasonal changes on Neptune, as you testify on this very blog above, but the much stronger incident sunshine on the face of Jupiter is considered inconsequential? The fact is Jupiter is a strong case for solar driven climate change. The Great Red Spot is a singular weather event without a peer or analog on any of the other known worlds. Some people insist on describing it as a hurricane. This is incorrect. A hurricane is a low pressure zone funneling surrounding warm air to the ground. The Great Red Spot is a high pressure zone, forcing hot air out of the middle of the planet. It rises 8 kilometers above the surrounding methane cloud deck, like a turkey timer that is popping out to tell us that the thanksgiving meal is ready. And now we have another great red spot, which will probably be with us for a very very long time. Neptune is changing in a spectacular and miraculous way which a cut and dried pdf file will not impart to you. Have a look at it in color. Neptune's orbit is 164 years long, and Voyager only visited it once back in 1989, so we have no baseline to judge if this change is the natural effect of Neptune traveling through it's orbit, or if it is the result of an augmented solar effect. But either way it is the sun driving Neptune's weather. Voyager was launched in 1977 and didn't get to Neptune until 1989. Right now, thirty years later, Voyager still has ten more years of travel before it reachs the heliopause, where the solar wind gives way to the pressure of interstellar space. So don't let this joker fool you that the sun is too weak or feeble to affect Jupiter.
131383. greenman3610 at 19:28 PM on 13 September 2007
        Climate change on Jupiter
        thanks for this post, and for this blog. In the rapidly expanding field of denialist-squashing websites, this one is a standout.
131384. Ben Lankamp at 17:38 PM on 13 September 2007
        It's the sun
        An increase of 1365,7689 to 1366,6620 is not in any way statistical significant. Pick two others years and you get a decrease (e.g. what Lockwood did). You did not account for the 11-year periodic cycle which needs to be substracted before looking at trends, which underlines the uselessness of randomly picking TSI from any given year or years. Ergo: looking at the data with the 11-year cycle substracted, the trend in the last 50 years is more or less neutral (+0,08 W/m²) and in any case not statistical significant, given the amount of variance in that same period. Inciding IR upon the Earths surface is not ~240 W/m², sure I agree with that, but then again I am not claiming it is (I said it was the outgoing flux at the TOA). The ~469 W/m² is the [total] incoming IR at the surface, which is a combination of solar flux and radiation coming from the GHGs (water vapour, carbon dioxide, so on). IPCC puts it at 492 W/m² as a consensus though. Of that amount about 452 W/m² goes into the atmosphere by latent heat exchange, evapo(trans)piration and absorption by GHGs (the latter roughly 350 W/m²). The atmosphere itself radiates 195 W/m² upwards into space and 324 W/m² downwards towards the surface. About 40 W/m² makes it directly from the Earth's surface into space. The incoming solar flux is ~235 W/m² (and outgoing as well), of which 67 W/m² is absorbed by the atmosphere and 168 W/m² reaches the surface. So summarizing: the [surface] incoming flux is ~492 W/m² and outgoing as well, the TOA incoming and outgoing flux is ~235 W/m². The atmosphere absorbs 519 W/m², most of it from below from the Earth's surface, and emits this upwards and downwards (mostly the latter). As far as I can tell, nothing of this appears in real contradication with your article from Manrique (2007). The 5.34/5.35 is indeed in W/m², I stand corrected. The ln(co2/co2_orig) only scales the value and deltaF is in W/m². Ben
131385. biocab at 13:03 PM on 13 September 2007
        Temp record is unreliable
        The error is 2.6 K: http://biocab.org/NOAA_vs._UAH.jpg
        Response: When comparing temperature anomalies, the trend is what you want to look at, not absolute values. Temperature anomaly is calculated as the difference from a baseline average. Often different temperature datasets use different baseline periods (eg - 1960 to 1990 or 1978 to 2000). However, the trend will be the same regardless of the period. In the case of the NOAA vs UAH graph, the trends are very similar. An additional complication is there is much uncertainty in satellite data regarding correcting for long term satellite drift (see our Satellite page for more info)
131386. biocab at 13:00 PM on 13 September 2007
        It's the sun
        I don't agree with consensus, I agree with science. In the last 50 years the Intensity of Solar Irradiance increased in 1981 uo to 1366.6829 W/m^2. Higher than in 1957 (1365.7689 W/m^2); consequently, in 1981 was higher than 50 years ago. In 2000 the ISI was 1366.6620 W/m^2, and it was higher than 50 years ago (ISI in 1957 was 1365.7689 W/m^2). The last year (2006) the ISI was 1367.25 W/m^2, higher than in 1957, 1981 and 2000. Is ISI increasing or decreasing in the last 50 years? The inciding IR upon the surface is not 240 W/m^2, but ~469 W/m^2. From the last load of energy, the surface absorbs ~356.15 W/m^2 (median ~342 W/m^2) (1- Manrique, José Ángel V. Transferencia de Calor. 2002. Oxford University Press. England. 2- Maoz, Dan. Astrophysics. 2007. Princeton University Press. Princeton, New Jersey Some scientists from the IPCC think that the value 5.35 W/m^2 is wrong... I agree: http://www.nap.edu/catalog.php?record_id=10787
131387. biocab at 11:35 AM on 13 September 2007
        It's the sun
        5.35 needs to have units: delta T = W/m^2 [Ln (ppmv/ppmv)] / 4 (W/m^2*K^4) (K^3) If don't, how could we eliminate W/m^2 from Stephan-Boltzmann constant?
131388. Ben Lankamp at 06:24 AM on 13 September 2007
        It's the sun
        Biocab: surely you can agree with the consensus that solar irradiance has not increased significantly in the last 50 years, while the global average temperature has? The only conclusion can be that changes in solar irradiance cannot have contributed to recent warming in the last half century. With regard to CO2: I think you are not completely aware of the exact concept of the natural greenhouse effect, the enhanced greenhouse effect and most important of all radiative forcing. I am not an expert on the exact chemistry of all the trace gases and how that works, so I cannot judge your comments on the exact emissivity (though my gut feeling hints at the missing of the immediate re-emittance of longwave IR-radiation while you seem to be talking only about the independent emittance of the absorbed heat). I do know the following though: the absolute value of carbon dioxide (whether expressed in ppm or Pp) is not relevant when it comes to the increase or decrease of the Earth's surface temperature. Changes in the exact amount of each gas are what is important. The reason for this is that such changes will cause changes in radiative fluxes and, as a part of the total atmospheric adjustment for these radiative inbalances, the earth's surface cools or warms. Now given that carbon dioxide concentrations have risen at least 35% since 1900, there surely must have been some warming due to carbon dioxide (though not due to the existance of the gas in the first place, but because of the increase in its concentration). I am more at home in meteorology, so some rough calculations about that: the upward surface flux of the earth is around 390 W/m² (sigma T^4 = 5,6704x10^-8 * 288^4 ~ 390) and the outward flux at the top of the atmosphere is (1-a)S/4 where a ~ 0.3 (the global, terrestial albedo of the atmosphere) so this flux comes down to about 240 W/m². Now you can easily see that a large amount of longwave radiation must have been absorbed by the atmosphere, roughly 150 W/m². We know that water vapour is by far the primary absorber and carbon dioxide relatively weak (that is what you have showed, I think). Then comes radiative forcing: this can be understood simply by looking at toy models, which show that if the solar input or emissivity of the earth or the atmosphere (e.g. the greenhouse gasses) changes, the Earth's surface temperature changes. To conclude, models have shown that a doubling in CO2 concentration will likely cause a radiative forcing of around 3,7 W/m². One can now find that the coefficient for determining the radiative forcing caused by an increase or decrease of CO2 concentration from any given value A to B, will be C = 3.7 / ln(2) = 5.34 (and reversing the equation results in DF = 5.34 ln(co2/co2_orig) ). I am just a layman but I am pretty sure the value you quoted, 5.35, is NOT the total emissivity of carbon dioxide but only a coefficient effectively indicating the climate sensitivity to CO2 doubling. The value is not even in W/m² but dimensionless. Note of caution: I consider myself a layman and excuse me for any dramatic failures in reasoning. Willing to learn though :). Ben
131389. biocab at 03:45 AM on 13 September 2007
        It's the sun
        I think I have the right to argue on my article based on peer reviewed papers. When we consider a short period, for example an 11 years period we can argue that the intensity of the solar irradiance is decreasing; however, if we consider a longer period, for example 400 years, we can see that the intensity of solar irradiance has not decreased. Some 400 years ago the solar irradiance intensity was 1365.5946 W/m^-2, while in 2000 the total solar irradiance intensity was 1366.6620 W/m^2. This year the Sun has been mostly spotless, but the solar irradiance intensity has been 1365 W/m^-2. This constitutes evidence on the existence of other solar "pulses" that we have not understood well: http://science.nasa.gov/headlines/y2003/17jan_solcon.htm Regarding the particularity of CO2 on the global warming, I don't see why to blame the CO2 of GW when its particular thermal characteristics show that the CO2 is not capable of producing any warming. The Pp of the CO2 in the atmosphere is roughly 0.00034 atm*m, wich limits the absorptivity-emissivity of the CO2 to only 0.00092 (dimensionless value), not the 0.2 given by the IPCC. The absorptivity-emissivity of CO2 is 0.00092 conduces to its total emittancy of barely 0.414 W/m^2, not the 5.35 W/m^2 given by the IPCC. If I was to blame any atmospheric gas of a GH effect, I would blame the Water Vapor, not the the coolant CO2.
        Response: "its particular thermal characteristics show that the CO2 is not capable of producing any warming"
        
        On the contrary, the enhanced greenhouse effect from CO2 has been confirmed by multiple lines of empirical evidence (eg - satellite measurements of infrared spectra, surface measurements finding more downward infrared radiation warming the planet’s surface).
        
        "If I was to blame any atmospheric gas of a GH effect, I would blame the Water Vapor, not the the coolant CO2."
        
        You would be right in that water vapour is the most dominant greenhouse gas. It's also the dominant positive feedback in our climate system and amplifies any warming caused by changes in atmospheric CO2. This positive feedback is why climate is so sensitive to CO2 warming.
131390. ScaredAmoeba at 18:16 PM on 12 September 2007
        It's the sun
        Just assuming for the sake of argument that your assertions based upon http://biocab.org/Solar_Irradiance_is_Actually_Increasing.html#anchor_15
        are proven by peer-reviewed studies to be correct and that: -
        Recent oppositely directed trends in solar climate forcings and the global mean surface air temperature BY MIKE LOCKWOOD AND CLAUS FROHLICH
        is shown by peer-reviewed studies to be wrong in some way, that still does not invalidate the fact that Solar output [once the 11-year cycle has been removed], has had no tend or virtually no trend. http://www.pmodwrc.ch/tsi/composite/pics/org_comp2_d41_61_0705.png
        Claims that the recent anomalous warming are solely due to solar effects are unsustainable. It is clear that the current anomalos warming cannot be explained without including the effects of GHGs and CO2 in particular.
        
131391. ScaredAmoeba at 15:59 PM on 11 September 2007
        It's not bad
        This NY Times article apparently refers to the following document: “Estimating Future Costs for Alaska Public Infrastructure At Risk from Climate Change”
        Response: Many thanks, I've updated the link (under Economical) - always good to go direct to the source!
131392. Greg F at 13:34 PM on 11 September 2007
        Models are unreliable
        Look at plate 1 in Hansen's 88 paper, the model includes the oceans. Hansen's Scenario C is the one that most closely matches the "Land – Ocean" temperature. John Cook wrote: "A way to test the accuracy of models is through hindcasting - see whether they successfully predict what has been observed over the past century." Not true for any model. All that shows is they can fit the model to the history. That is beside the point as the IPCC does not claim that the models can predict anything. John Cook wrote: "The key point is that all the models fail to predict recent warming without taking rising CO2 levels into account." Given enough "tunable parameters" that should come as no surprise. The modelers also assume that there is some positive feedback, there is no proof that this is the case. Here is one for you straight from the IPCC, Chapter 8, page 596: "The number of degrees of freedom in the tuneable parameters is less than the number of degrees of freedom in the observational constraints used in model evaluation." IOW, the models are nothing more then sophisticated curve fits. Calling the models "predictions" does not instill confidence that you have done your homework. Kevin E. Trenberth http://blogs.nature.com/climatefeedback/2007/06/predictions_of_climate.html "In fact there are no predictions by IPCC at all. And there never have been. The IPCC instead proffers “what if” projections of future climate that correspond to certain emissions scenarios." And from the same letter: "Even if there were, the projections are based on model results that provide differences of the future climate relative to that today. None of the models used by IPCC are initialized to the observed state and none of the climate states in the models correspond even remotely to the current observed climate. In particular, the state of the oceans, sea ice, and soil moisture has no relationship to the observed state at any recent time in any of the IPCC models." John Cook wrote: "Satellite measurements show that the troposphere is warming" The models predict that the troposphere should warm faster then the surface, it isn't.
        Response: Re tropospheric warming, I recommend reading Satellite show little to no warming in the troposphere. The argument over "prediction" vs "projection" is semantics. Kevin Trenberth is merely saying we don't know with certainty what future emissions will be so we make predictions based on various emission scenarios. However, lest it be a stumbling block, I'll update the text. Thanks for the feedback!
131393. ScaredAmoeba at 02:32 AM on 11 September 2007
        Human fingerprint on atmospheric CO2
        The contrarians' dismissal of the tiny percentage of anthropogenic CO2 as therefore automatically insignificant is shown to be completely fallacious by an interesting analogy drawn by Professor Andrew Pitman, Climatologist at UNSW.
        Professor Pitman reminds us that the Ebola virus, whilst undeniably microscopic is hardly insignificant to human health.
        This link is to an interview with Martin Durkin about his mockumentary The Great Global Warming Swindle.
        See the upper video at 06.18
131394. ScaredAmoeba at 02:14 AM on 11 September 2007
        Stephen Schwartz on climate sensitivity
        One thing that is often overlooked is that irrespective of whether CO2 causes warming, [I for one, will stick with the science]. Increasing CO2 will result in acidification [reducing pH] of the ocean. There are a number of studies that show that this is likely to be bad thing. AFAIK, no peer-reviewed scientific studies have suggested it is a good idea, although I look forward to a new study - perhaps “authored” by ExxonMobil et al. What Corals are Dying to Tell Us About CO2 and Ocean Acidification - Caldeira "Emissions of carbon dioxide are causing the oceans to become more acidic. Recent experiments show that this ocean acidification threatens many ocean ecosystems. The ancient past may provide a cautionary tale, indicating what might happen if we change ocean chemistry too much too fast. end quote" Effects of carbon dioxide and climate change on ocean acidification and carbonate mineral saturation - Long Cao, Ken Caldeira, and Atul K. Jain "We use an earth system model of intermediate complexity to show how consideration of climate change affects predicted changes in ocean pH and calcium carbonate saturation state. Our results indicate that consideration of climate change produces second-order modifications to ocean chemistry predictions made with constant climate; these modifications occur primarily as a result of changes in sea surface temperature, and climate induced changes in dissolved inorganic carbon concentrations." Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms – Orr et al. "Today’s surface ocean is saturated with respect to calcium carbonate, but increasing atmospheric carbon dioxide concentrations are reducing ocean pH and carbonate ion concentrations, and thus the level of calcium carbonate saturation. Experimental evidence suggests that if these trends continue, key marine organisms—such as corals and some plankton—will have difficulty maintaining their external calcium carbonate skeletons. Here we use 13 models of ocean–carbon cycle to assess calcium carbonate saturation under the IS92a ‘business-as-usual’ scenario for future emissions of anthropogenic carbon dioxide. In our projections, Southern Ocean surface waters will begin to become undersaturated with respect to aragonite, a metastable form of calcium carbonate, by the year 2050. By 2100, this undersaturation could extend throughout the entire Southern Ocean and into the subarctic Pacific Ocean. When live pteropods were exposed to our predicted level of underaturation during a two-day shipboard experiment, their aragonite shells showed notable dissolution. Our findings indicate that conditions detrimental to high-latitude ecosystems could develop within decades, not centuries as suggested previously."
        Response: Thanks for the links, I've added ocean acificiation to the list of negatives on the Global Warming is Good page.
131395. JohnMashey at 07:19 AM on 10 September 2007
        Schulte vs Oreskes on consensus, Round 2
        You may want to check out: Stranger Fruit as it has a jolly tiff, with lawsuits threatened, bloggers ordered to be silent, etc.
        Response: Thanks for the link. The comments are particularly interesting (I had a laugh at Eli Rabbett's comment at the end).
131396. jimdk at 04:16 AM on 10 September 2007
        It's the sun
        "From the actual data we conclude that the graphs from Lockwood and Frölish were flawed: 1. The methodology used by Lockwood and Frölish to smooth the lines was applied only to maxima of R (sunspot number), dismissing the TSI. This practice hides the minima, which for the issue are more important than the maxima. For example, if the minimum of TSI in 1975 was 1365.5 W/m^2, it would contrast dramatically with the minimum of TSI of 1998 that was 1366 W/m^2 (0.033% higher). That would make the Sun in 1975 “colder” than in 1998. However, if we compare minimum values with maximum values, then the Sun would be frankly “warmer” in 1998 -when the solar energy output was 1366 W/m^2- than in 1975 -when the energy output was 1366.1111 W/m^2. Today (21/07/07), the global TSI was 1367.6744 W/m^2); hence, we see that we must not smooth maxima values through movable trends because we would be hiding the minima values, which are more important because the baseline of the “cooler” or lower nuclear activity of the Sun are higher everyday. The coolest period of the Sun happened during the Maunder Minimum when the TSI was 1363.5 W/m^2. The coolest period of the Sun from 1985 to date occurred in 1996 when the TSI was 1365.6211 W/m^2. An interesting blotch is that in 1985 the TSI was 1365.6506 W/m^2 and in 2000 was 1366.6744." http://biocab.org/Solar_Irradiance_is_Actually_Increasing.html#anchor_15
131397. windyridge at 03:58 AM on 5 September 2007
        Klaus-Martin Schulte and scientific consensus
        Fascinating stuff, keep it coming and hopefully alot of people will read.

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