Sigh.... I'm really disappointed by the ignorance that people have about climate change. No wonder our governments aren't doing anything to help, the voting public does not understand the issue. I've put down my thoughts in the comments section of "Climate Change—Don’t Blame It on the Sun"... I won't bother to post again here.

CO2 has such a greater affect than H2O because of the relative concentrations. H2O and CO2 absorb at certain wavelengths. Since the atmosphere is already saturated with H2O, it is already absorbing all it can at that particular wavelength. Since there is much less CO2, an increase in CO2 means the atmosphere will absorb more efficiently at that particular wavelength. For the same reason, CH4 and N2O have a greater warming potential than CO2. As for warming on Mars and Titan.... I assure you we know much more about our own planet...

So, first I check out Phil Valentine on wikipedia, I had never heard of him. And he's a conservative radio talk show host in Tennessee. Great. I'm sure he's an expert on this subject area then :) Anyways.... ok first link.... Temperature monitors report widescale global cooling http://www.dailytech.com/Temperature+Monitors+Report+Worldwide+Global+Cooling/article10866.htm Ok, so he's using anecdotal evidence of cold weather this year to support the idea that the planet is actually cooling, rather than warming. Well, anecdotal evidence is a terrible indicator of a long term trend. Also, he says that NASA and others have data indicate that this year was cooler on average than previous years. Fair enough. But one cool year is not an indication of a long term climate change. That's why scientists are typically looking at 10, 30 and 50 year trends. Global weather is sort of like the stock market..... it's always going up and down. Since you don't like the IPCC (I'll address that later...) here's a peer reviewed article to support this: Antarctic atmospheric temperature trend patterns from satellite observations Johanson CM (Johanson, Celeste M.), Fu Q (Fu, Qiang) GEOPHYSICAL RESEARCH LETTERS Volume: 34 Issue: 12 Article Number: L12703 Published: JUN 19 2007 I have access to it through my academic institution, you may have trouble getting access to it though, or you might need to pay, I'm not sure. A bit further down the page: Study finds natural cause for rapid Arctic warming http://www.dailytech.com/Study+Finds+Natural+Cause+for+Rapid+Arctic+Warming/article10216.htm So wow.... someone would read this and think that these scientists have found a natural explanation for global warming.... ok, lets take a look at the original research: Vertical structure of recent Arctic warming published in Nature, you can read the abstract here: http://www.nature.com/nature/journal/v451/n7174/pdf/nature06502.pdf So first of all, if my research actually debunked the current understanding of global warming, I sure would have put that into the title! If you read the abstract, really what this article is about is that these researchers measured the vertical structure of the warming trend of arctic temperatures. They found at higher altitudes, the atmosphere is actually warming up faster than at the ground surface. The arctic is currently warming much faster than people expected. One of the possible explanations is that as sea ice and snow melts, the changing albedo allows the earth surface to absorb more radiation, and increase in temperature. The higher temperature increases at high altitudes indicates that instead, it is likely related to atmospheric circulation. Therefore, if you read the original article, you can see that this research had absolutely nothing to do with finding a "natural cause" for global warming. They are conducting new research into some of the feedback mechanisms that causes certain parts of the globe to heat up faster than others. See here's the thing. Greenhouse gases (especially CO2) are the major cause of warming. You can't deny that the concentration of these gases are increasing. You can check out the raw data here: http://agage.eas.gatech.edu/index.htm The climate forcing attributed to increasing concentrations of greenhouse gases is dead easy to calculate. CO2 for example will absorb infra-red radiation at a very specific wavelength. This can be measured in the lab. We know what wavelengths the earth emits (blackbody radiation). Then it can easily be calculated. Ignoring all other factors, the increasing concentrations of these gases will lead to global warming (or more accurately climate change, since some areas actually cool in response to changing atmospheric and oceanic circulations patterns). Climate forcing attributed to greenhouse gases far outweighs the forcing attributed to other factors. Where is this CO2 (and other gases) coming from. Well, again, it's easy to calculate using a simple mass balance approach. We know how much we are producing, and how much is produced naturally, and how much is absorbed naturally. It's also easy to prove this by measuring the isotopic composition of atmospheric CO2. Again, since you don't like the IPCC, here's another article (again you might have trouble tracking it down): Anthropogenic emissions of CO2 and CH4 in an urban environment Kuc T, Rozanski K, Zimnoch M, Necki JM, Korus A APPLIED ENERGY Volume: 75 Issue: 3-4 Pages: 193-203 Published: JUL-AUG 2003 As for the IPCC... I think they are doing a great job of communicating the science to the policymakers. The job of scientists is to determine the truth and then communicate it to the public and to the governments. It fine to debate about what should be done or what shouldn't be done in response to climate change, but it's counterproductive to pretend that there is a debate in the scientific community when this really isn't the case. As far as the IPCC reports are concerned.... if anything, they actually represent a very conservative estimate of the risks/causes of climate change. Since the IPCC committees are drawing from published scientific literature to write these reports, they always lag a couple years behind the most recent data. Also, the IPCC scientists are under a lot of pressure not to overstate the climate change issues, because, although they are not a political entity, they do face political pressure to be more "industry friendly". Also, the reports risk being dismissed if they are too alarmist. You can read more about the IPCC on the wikipedia entry, and make your own decision. http://en.wikipedia.org/wiki/Intergovernmental_Panel_on_Climate_Change Since wikipedia is open to public editing, you could argue that it is not too biased. But to summarize, you need to base your arguments on actual peer reviewed articles. The peer review process is what ensures that scientific research is valid and bias free. I like to refer to the IPCC because they draw from peer reviewed research, and they are experts in the field as well.

One of the major challenges facing the poor in Sub-Sahara Africa is the lack of nitrogen nutrients in the soil. This lack of nitrogen makes it very difficult for them to grow food to support themselves. A very cost effective way to reduce hunger in this region is to supply these farmers with simple fertilizer and seed. This is part of the UN Millennium Villages project, and so far has had great success in these trial villages. Check out this video for more information: http://nitrogen2007.com/videos/One_Season_low_bitrate.avi

There is no doubt in anyone's mind that the planet goes through natural cycles. However, the driving force behind current climate change is undoubtedly anthropogenic. If you need more convincing take a look at figures 2.4 and 2.5 in the latest IPCC synthesis report. http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr_topic2.pdf Figure 2.4 is a breakdown in the magnitude of radiative forcing attributed to many different factors. From the figure, it is obvious that the natural cycles in solar irradiance are minuscule compared to the effects from various greenhouse gases. Figure 2.5 is a comparison between climate models run using only natural inputs vs. natural inputs plus greenhouse gases. As you can see, only the models that include the effects of greenhouse gases are able to simulate the recent temperature increase. I find it funny when people like you claim to be open minded. It's the same argument people use to denounce evolution. Just because you believe something to be true doesn't make it equally as valid as an opposite viewpoint unless you have scientific evidence to back it up. Your viewpoint that climate change is potentially caused by natural cycles would be fine if you had some evidence to support it. However, there is an overwhelming body of evidence proving that current climate change is being driven by anthropogenic factors. If you have some references to some recent scientific work that would support your assertions that natural cycles are responsible for climate change, I would love to read them. Please post them!! Then maybe we can have a real scientific discussion. Your statement in your first comment proves that you have absolutely no idea about the science behind climate change. ("Some uninformed legislator may see the last sentence of the article and proposed a law prohibiting us from breathing.") Yes, the amount of CO2 added to the atmosphere through the combustion of fossil fuels is small compared to the amount that is naturally cycled through the environment (http://en.wikipedia.org/wiki/Carbon_cycle). The problem is that this upsets the fine balance of sinks and sources, and causes the concentration to slowly increase. This increase drives the increase in global temperatures. The fact that Al Gore drives an SUV has absolutely nothing to do with the causes of climate change. You might argue that he is being hypocritical, since he is advocating that people drive smaller vehicles, but this does nothing to change the scientific facts! And lastly, I've noticed a fair bit of whining about the quality of the articles lately. I think that PopSci is doing a great job. I don't think these articles were ever intended to be full length and in depth. The website is just a free supplement to the magazine. Also, have you ever been to a scientific conference? You are often overwhelmed with information. Really, the goal is to try and sample as much of the new scientific research as you can. The presenters are often trying to make a simple point in a very short amount of time allotted to them. That was the point of this article. PopSci is trying to give us a taste of what is happening at the AAAS meeting in Boston. The point of this particular presentation was that there is further proof that the sun is not responsible for recent climate change. Please, I am very much open to further discussion on this topic.