Skip to main content

Home/ Advanced Concepts Team/ Group items tagged climate change

Rss Feed Group items tagged

13More

Nature Paper: Rivers and streams release more CO2 than previously believed - 6 views

  •  
    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...
  • ...10 more comments...
  •  
    This could also be a mechanism to counter human CO2 emission ... the more we emit, the less turbulent rivers and stream, the less CO2 is emitted there ... makes sense?
  •  
    I guess there is a natural equilibrium there. Once the climate warms up enough for all rivers and streams to evaporate they will not contribute CO2 anymore - which stops their contribution to global warming. So the problem is also the solution (as always).
  •  
    "The source of inland water CO2 is still not known with certainty and new studies are needed to research the mechanisms controlling CO2 evasion globally." It is another source of CO2 this one, and the turbulence in the rivers is independent of our emissions in CO2 and just facilitates the process of releasing CO2 waters. Dario, if I understood correct you have in mind a finite quantity of CO2 that the atmosphere can accomodate, and to my knowledge this does not happen, so I cannot find a relevant feedback there. Johannes, H2O is a powerful greenhouse gas :-)
  •  
    Nasia I think you did not get my point (a joke, really, that Johannes continued) .... by emitting more CO2 we warm up the planet thus drying up rivers and lakes which will, in turn emit less CO2 :) No finite quantity of CO2 in the atmosphere is needed to close this loop ... ... as for the H2O it could just go into non turbulent waters rather than staying into the atmosphere ...
  •  
    Really awkward joke explanation: I got the joke of Johannes, but maybe you did not get mine: by warming up the planet to get rid of the rivers and their problems, the water of the rivers will be accomodated in the atmosphere, therefore, the greenhouse gas of water.
  •  
    from my previous post: "... as for the H2O it could just go into non turbulent waters rather than staying into the atmosphere ..."
  •  
    I guess the emphasis is on "could"... ;-) Also, everybody knows that rain is cold - so more water in the atmosphere makes the climate colder.
  •  
    do you have the nature paper also? looks like very nice, meticulous typically german research lasting over 10 years with painstakingly many researchers from all over the world involved .... and while important the total is still only 20% of human emissions ... so a variation in it does not seem to change the overall picture
  •  
    here is the nature paper : http://www.nature.com/nature/journal/v503/n7476/full/nature12760.html I appreciate Johannes' and Dario's jokes, since climate is the common ground that all of us can have an opinion, taking honours from experiencing weather. But, the same as if I am trying to make jokes for material science, or A.I. I take a high risk of failing(!) :-S Water is a greenhouse gas, rain rather releases latent heat to the environment in order to be formed, Johannes, nice trolling effort ;-) Between this and the next jokes to come, I would stop to take a look here, provided you have 10 minutes: how/where rain forms http://www.scribd.com/doc/58033704/Tephigrams-for-Dummies
  •  
    omg
  •  
    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
1More

Risky Business | The Economic Risk of Climate Change in the US | Risky Business - 2 views

  •  
    interesting report on the cost of climate change for the US ... coming from Bloomberg and financed by him might not give it its utmost credibility but still
3More

IPCC models getting mushy | Financial Post - 2 views

  •  
    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
1More

Climate Futures: responses to climate change in 2030 | Forum For The Future - 0 views

  •  
    Some predictions on our climate - something which might help for the YGT description...
3More

Aerosols make methane more potent - 1 views

  •  
    "climate policy-makers need to pay much more attention to restricting short-lived pollutants, such as methane, carbon monoxide, volatile organic compounds (VOCs) and aerosols. This could create significant changes in the local and global climate quite quickly, whereas the effects of efforts to reduce emissions of long-lived carbon dioxide will not be seen for many years."
  •  
    interesting indeed ... but coming at the right time before copenhagn?
  •  
    These conclusions come too late to have a real impact on decisions that will be taken in Copenhagen, I assume. But I think it is a hot topic as climate change 'solutions' that work QUICKLY are more and more needed!!
7More

Letter from Intergovernmental panel on climate change. - 2 views

  •  
    To Coordinating Lead Authors, Lead Authors, and Review Editors for the Fifth Assessment Report (AR5) "I would also like to emphasize that enhanced media interest in the work of the IPCC would probably subject you to queries about your work and the IPCC. My sincere advice would be that you keep a distance from the media and should any questions be asked about the Working Group with which you are associated, please direct such media questions to the Co-chairs of your Working Group and for any questions regarding the IPCC to the secretariat of the IPCC." and an amusing related memo on how to deal with reporters if you can't avoid them. I particularly enjoyed the list of words that mean one thing to scientists and something else to other people. https://docs.google.com/fileview?id=0B88iFXWgVKt-NDc2N2FiM2QtYzQzYS00MWMxLWE4MGEtZjUwZDlmNzc3MTcz&hl=en
  • ...4 more comments...
  •  
    This. Memo. Is. Awesome.
  •  
    quite weird this note of IPCC... I feel more like people have to be educated...
  •  
    i agree. however, (and perhaps it would have been useful to post my source which didn't seem so interesting at the time) the contents of this particular memo seems to have been interpreted as a more or less direct consequence of "ClimateGate" rather than standard practice. http://freakonomics.blogs.nytimes.com/2010/07/14/what-we-talk-about-when-we-talk-about-climate-change/ On the other hand, I'd suggest that talking to the press is not necessarily a great way of educating the public, there being some truth i think to the contents of the memo.
  •  
    don't know why this seems weired or shocking - looks like some good practice advice to me
  •  
    well compare to ESA it's sure it doesn't seem weird. Imagine one second a journal article about climate change: "We contacted Dr. X of the IPCC, who refused to answer to our questions..."
  •  
    this is not what the memo recommends ... it just says speak only about what you can confidently speak about and refer to others for other questions ...
1More

ScienceDirect - Current Biology : The missing climate change policy - 2 views

  •  
    "Affluent western individuals are increasingly fretting about the carbon dioxide emissions from their lifestyle and energy use but one key issue, having fewer children, is little considered. " If sb has access to the article... Having fewer children as a solution to climate change makes me curious...
2More

Royal Society Fellows Question Body's Climate Change Statements - 1 views

  • The Royal Society has released a statement acknowledging that its climate guide is being updated and noting: "The new guide has been planned for some time but was given added impetus by concerns raised by a small group of Fellows of the Society that older documents designed to challenge some of the common misrepresentations of the science were too narrow in their focus."
  •  
    The "climatosceptics" are more and more powerful, in France it's crazy how much they are in newspaper and television... Before it was fancy to fear the global warming, now it's fancy to fight the "dictat" of the Science, as if Science was a religion with its dogma !
1More

Air travel and climate: A potential new feedback? - 0 views

  •  
    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?
1More

Global Warning - a project of the National Security Journalism Initiative - 0 views

  •  
    "WASHINGTON, D.C. - In a three-month investigation, a team of Northwestern University student reporters has found that the US nation's security establishment is not adequately prepared for many of the environmental changes that are coming faster than predicted and that threaten to reshape demands made on the military and intelligence community. This is despite the fact that the Defense Department has called climate change a potential "accelerant of instability." The Medill School of Journalism graduate student team began publication on January 10 of its findings on the national security implications of climate change with a series of print, video and interactive stories."
2More

A harsh critics to GCMs from Judith Curry - 2 views

  •  
    "By extension, GCMs are not fit for the purpose of justifying political policies to fundamentally alter world social, economic and energy systems. It is this application of climate model results that fuels the vociferousness of the debate surrounding climate models."
  •  
    but you know wo these global warming policy foundation is, do you? they are the main advocacy group for climate change deniers in the UK, nothing scientific to start with; fine to post here reasonable scientific papers criticising global climate models but please not this shit
1More

Dynamic Coalition on Internet and Climate Change - 0 views

  •  
    IGF - The Internet Governance Forum. Did you know that the Internet and its usage are responsible for 5 per cent of the world's total electricity consumption
1More

Management of trade-offs in geoengineering through optimal choice of non-uniform radiat... - 1 views

  •  
    Nice modelling research on geo engineering options ...
5More

Betting on Green - 5 views

  •  
    breakthroughs vs. accelerated deployment in climate change mitigation technologies.
  • ...2 more comments...
  •  
    interesting guy indeed ... "Forget today's green technologies like electric cars, wind turbines, solar cells and smart grids, in other words. None meets what Mr Khosla calls the "Chindia price"-the price at which people in China and India will buy them without a subsidy. "Everything's a toy until it reaches that point," he says. I also like this one since its a bit like ACT topic selection: ""I am only interested in technologies that have a 90% chance of failure but, if they do succeed, would change the infrastructure of society in some radical way," he says." should we propose SPS to him ? :-)
  •  
    one more: ""I never compute returns. If you start forecasting cash flows, you lose innovation, you lose instinct. You average yourself down to mediocrity." "I've had many more failures than successes in my life," admits Mr Khosla. "My willingness to fail gives me the ability to succeed."
  •  
    indeed. puts me in mind of the often reinvented private ACT idea. actually there's a bunch of interesting looking articles on his website. http://www.khoslaventures.com/khosla/papers.html . No sps in the solar one as far as i can tell :) found this bit intriguing too in that, albeit presumably out of context, it doesn't make sense ""The solution to our energy problems is almost the exact opposite of what Khosla says," declares Joseph Romm, who is the editor of Climate Progress, an influential climate blog, and a senior fellow at the Centre for American Progress Action Fund, a think-tank. "Technology breakthroughs are unlikely to be the answer. Accelerated deployment of existing technologies will get you down the cost curve much more rapidly than a breakthrough."" found this seemingly not very well considered piece (to be fair a blog post) by the guy http://climateprogress.org/2010/07/02/is-anyone-more-incoherent-than-vinod-khosla/ . maybe he's written some more convincing stuff in this vein somewhere.
  •  
    "Mr Khosla (...) is investing over $1 billion of his clients' money in black swans" Well, with his own money his approach might be a little different :-)
1More

CFC Replacements Intensify Climate Concerns - 0 views

  •  
    "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...
3More

BBC NEWS | Asia-Pacific | Scientists bring snow to Beijing - 2 views

  •  
    Did you know about this Weather Modification Office? Promising or dodgy?
  •  
    Yes. In China it happens apparently quite often that weather is regionally modified, e.g. in order to have good weather conditions during certain events (like olympics in Beijing). But also in other countries weather modification is applied, for reasons of agriculture, pollution, skiing, etc. Obviously, one wonders on the environmental impact of such an artificial cloud feeding process with silver iodide. I just googled, stumbling upon this report http://www.weathermodification.org/AGI_toxicity.pdf which published the result: no environmentally harmful effects...
  •  
    and w.r.t. ur question: I mean different weather conditions which we experience locally (like droughts or other extreme weather events) are (often) due to large-scale/global climatic changes. Hence, cloud seeding just describes a local, short-term mitigation of these events. However, there is a geoengineering proposal (so climate modification) which also suggests to seed clouds above the sea (i.e. increase cloud coverage, e.g. by using seaspray as cloud condesation nuclei), thereby increasing the planetary albedo (Earth reflectance) and reducing the energy reaching the Earth surface. If this idea is promising or not, I couldn't judge upon, but for sure it is worthwhile to take a closer look at.
1More

9 Ways NASA Can Tackle Climate Change: Scientific American - 0 views

  •  
    NASA feeling the wind of change and not surprisingly its Pete Wordens boys that are fastest ... -LS
3More

NASA Brings Earth Science 'Big Data' to the Cloud with Amazon Web Services | NASA - 3 views

  •  
    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.
1More

Venus holds warning for Earth - 0 views

  •  
    Just in case you missed these one... should be of interest for ACT's climate modelling squad. "As well as telling us more about Venus, it could be sending a warning to those on Earth seeking to inject our atmosphere with sulphur droplets in an attempt to mitigate climate change."
1 - 20 of 77 Next › Last »
Showing 20 items per page