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Another underestimated source of CO2, are turbulent waters. "The stronger the turbulences at the water's surface, the more CO2 is released into the atmosphere. The combination of maps and data revealed that, while the CO2 emissions from lakes and reservoirs are lower than assumed, those from rivers and streams are three times as high as previously believed." Alltogether the emitted CO2 equates to roughly one-fifth of the emissions caused by humans. Yet more stuff to model...

Nasia, I thought about your statement carefully - and I cannot agree with you. Water is not a greenhouse gas. It is instead a liquid. Also, I can't believe you keep feeding the troll! :-P But on a more topical note: I think it is an over-simplification to call water a greenhouse gas - water is one of the most important mechanisms in the way Earth handles heat input from the sun. The latent heat that you mention actually cools Earth: solar energy that would otherwise heat Earth's surface is ABSORBED as latent heat by water which consequently evaporates - the same water condenses into rain drops at high altitudes and releases this stored heat. In effect the water cycle is a mechanism of heat transport from low altitude to high altitude where the chance of infrared radiation escaping into space is much higher due to the much thinner layer of atmosphere above (including the smaller abundance of greenhouse gasses). Also, as I know you are well aware, the cloud cover that results from water condensation in the troposphere dramatically increases albedo which has a cooling effect on climate. Furthermore the heat capacity of wet air ("humid heat") is much larger than that of dry air - so any advective heat transfer due to air currents is more efficient in wet air - transporting heat from warm areas to a natural heat sink e.g. polar regions. Of course there are also climate heating effects of water like the absorption of IR radiation. But I stand by my statement (as defended in the above) that rain cools the atmosphere. Oh and also some nice reading material on the complexities related to climate feedback due to sea surface temperature: http://journals.ametsoc.org/doi/abs/10.1175/1520-0442(1993)006%3C2049%3ALSEOTR%3E2.0.CO%3B2

I enjoy trolling conversations when there is a gain for both sides at the end :-) . I had to check upon some of the facts in order to explain my self properly. The IPCC report states the greenhouse gases here, and water vapour is included: http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-2-1.html Honestly, I read only the abstract of the article you posted, which is a very interesting hypothesis on the mechanism of regulating sea surface temperature, but it is very localized to the tropics (vivid convection, storms) a region of which I have very little expertise, and is difficult to study because it has non-hydrostatic dynamics. The only thing I can comment there is that the authors define constant relative humidity for the bottom layer, supplied by the oceanic surface, which limits the implementation of the concept on other earth regions. Also, we may confuse during the conversation the greenhouse gas with the Radiative Forcing of each greenhouse gas: I see your point of the latent heat trapped in the water vapour, and I agree, but the effect of the water is that it traps even as latent heat an amount of LR that would otherwise escape back to space. That is the greenhouse gas identity and an image to see the absorption bands in the atmosphere and how important the water is, without vain authority-based arguments that miss the explanation in the end: http://www.google.nl/imgres?imgurl=http://www.solarchords.com/uploaded/82/87-33833-450015_44absorbspec.gif&imgrefurl=http://www.solarchords.com/agw-science/4/greenhouse--1-radiation/33784/&h=468&w=458&sz=28&tbnid=x2NtfKh5OPM7lM:&tbnh=98&tbnw=96&zoom=1&usg=__KldteWbV19nVPbbsC4jsOgzCK6E=&docid=cMRZ9f22jbtYPM&sa=X&ei=SwynUq2TMqiS0QXVq4C4Aw&ved=0CDkQ9QEwAw

Sometime in the last few billion years, disaster struck one of Earth's nearest neighbours. Planetary geologists think there is good evidence that Venus was the victim of a runaway greenhouse effect which turned the planet into the boiling hell we see today. A similar catastrophe is almost certain to strike Earth in about 2 billion years, as the Sun increases in luminosity.

the actual paper: http://arxiv.org/abs/1201.1593 just wondering if their conclusion that the long term solution is to change the orbit of Earth is really the ultimate wisdom ...

A new mechanism was discovered on how H2 and N2 participate in the radiation budget. This may help to resolve the "faint young sun paradox", a hypothesis according to which during the earlier age of the solar system when sun radiation had lower intensity than now, the earth was warmer. Extended, it could reassess the past habitability of Mars.

why am I not surprised .....

http://www.academia.edu/4210419/Can_climate_models_explain_the_recent_stagnation_in_global_warming A view of well-respected scientists on how to proceed from here, that was rejected from Nature. In any case, a long way to go...

unfortunately it's too early to cheer and burn more coal ... there is also a nice podcast associated to this paper from nature Recent global-warming hiatus tied to equatorial Pacific surface cooling Yu Kosaka & Shang-Ping Xie Nature 501, 403-407 (19 September 2013) doi:10.1038/nature12534 Received 18 June 2013 Accepted 08 August 2013 Published online 28 August 2013 Despite the continued increase in atmospheric greenhouse gas concentrations, the annual-mean global temperature has not risen in the twenty-first century1, 2, challenging the prevailing view that anthropogenic forcing causes climate warming. Various mechanisms have been proposed for this hiatus in global warming3, 4, 5, 6, but their relative importance has not been quantified, hampering observational estimates of climate sensitivity. Here we show that accounting for recent cooling in the eastern equatorial Pacific reconciles climate simulations and observations. We present a novel method of uncovering mechanisms for global temperature change by prescribing, in addition to radiative forcing, the observed history of sea surface temperature over the central to eastern tropical Pacific in a climate model. Although the surface temperature prescription is limited to only 8.2% of the global surface, our model reproduces the annual-mean global temperature remarkably well with correlation coefficient r = 0.97 for 1970-2012 (which includes the current hiatus and a period of accelerated global warming). Moreover, our simulation captures major seasonal and regional characteristics of the hiatus, including the intensified Walker circulation, the winter cooling in northwestern North America and the prolonged drought in the southern USA. Our results show that the current hiatus is part of natural climate variability, tied specifically to a La-Niña-like decadal cooling. Although similar decadal hiatus events may occur in the future, the multi-decadal warming trend is very likely to continue with greenhouse gas

"But researchers say what's good for ozone is bad for climate change. In the atmosphere, these replacement chemicals [replacements for CFCs] act like "super" greenhouse gases, with a heat-trapping power that can be 4,470 times that of carbon dioxide." Havent't heard of this before...

stratospheric ozone hole leads to decreased uptake of greenhouse gas CO2 by the ocean

once more ... the Romans did it already 2000 years ago! this time: burning so much wood that they increased the methane level in a way we can still measure it in ice cores ...

The researchers used a global climate model to show that if an extreme emissions pathway -- RCP8.5 -- is followed up until 2035, allowing temperatures to rise 1°C above the 1970-1999 mean, and then SRM (Solar Radiation Management) is implemented for 25 years and suddenly stopped, global temperatures could increase by 4°C in the following decades.

Nice quantitative study. They treat the problem within the full uncertainty range of climate sensitivity parameter (much uncertain), very complete. However, at SRM ceasing, after an initial positive spike of Radiative Forcing, the rate of warming seems to return to rates predicted for the non-geoengineering case: "The 20-year temperature trends following SRM cessation are 0.2−0.6 °C/decade for the range of climate sensitivities (figure 5), comparable to those trends that occur under the RCP8.5 scenario without any SRM." I am actually working on a similar idea for deliberate Mars terraforming: aiming to cool the planet down before we introduce a positive Temperature raising feedback with greenhouse gases, maybe could be more efficient than warming itself.

NASA answer to the big data hype

"The service encompasses selected NASA satellite and global change data sets -- including temperature, precipitation, and forest cover -- and data processing tools from the NASA Earth Exchange (NEX)" Very good marketing move for just three types of selected data (MODIS, Landsat products) plus four model runs (past/projection) for the the four greenhouse gas emissions scenarios of the IPCC. It looks as if they are making data available to adress a targeted question (crowdsourcing of science, as Paul mentioned last time, this time climate evolution), not at all the "free scrolling of the user around the database" to pick up what he thinks useful, mode. There is already more rich libraries out there when it comes to climate (http://icdc.zmaw.de/) Maybe simpler approach is the way to go: make available the big data sets categorized by study topic (climate evolution, solar system science, galaxies etc.) and not by instrument or mission, which is more technical, so that the amateur user can identify his point of interest easily.

They are taking a good leap forward with it, but it definitely requires a lot of post processing of the data. Actually it seems they downsample everything to workable chunks. But I guess the power is really in the availability of the data in combination with Amazon's cloud computing platform. Who knows what will come out of it if hundreds of people start interacting with it.

Global air travel contributes around 3.5 percent of the greenhouse gas emissions behind/driving anthropogenic climate change, according to the International Panel on Climate Change (IPCC). But what impact does a warming planet have on air travel and how might that, in turn, affect the rate of warming itself?

interesting perspective ... hopefully included by now in the list but I did not check ....

New method for geoengineering? New insight into methanotrophs, bacteria that can oxidise methane, may help us develop an array of biotechnological applications that exploit methane and protect our environment from this potent greenhouse gas. Publishing in Nature, scientists led by Newcastle University have provided new understanding of how methanotrophs are able to use large quantities of copper for methane oxidation.

A revolutionary new type of laser (fiber laser) is promising major advances in remote sensing of greenhouse gases.The new laser can operate (bed tuned) over a large range within the infrared light spectrum.

Reads too good to be true .... where is Isabelle when we need her ? :-)