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Emissions of Key Greenhouse Gas Stabilize
brian0918 writes "Multiple news sites are reporting that levels of the second most important greenhouse gas, methane, have stabilized". From Scientific American: "During the two decades of measurements, methane underwent double-digit growth as a constituent of our atmosphere, rising from 1,520 parts per billion by volume (ppbv) in 1978 to 1,767 ppbv in 1998. But the most recent measurements have revealed that methane levels are barely rising anymore — and it is unclear why." From NewScientist: "Although this is good news, it does not mean that methane levels will not rise again, and that carbon dioxide remains the 800-pound gorilla of climate change."
The real 800lb gorilla for methane is the Arctic. If the predictions are right then this is the calm before the storm. If the Arctic melts, which it is, it'll release vast amounts of methane. It's likely to dwarf all other greenhouse sources. Everyone seems to be ignoring the Arctic but all the CO2 sources combined can't compare so a melting Arctic should be our primary concern. If it's the canary then the canary isn't just dead but it has been reduced to a skeleton.
I do hope you were joking.
Just in case bozos out there actually believe it: The IPCC estimates that 60% of methane produced comes from our agriculture, industry, and waste. Humans are the biggest single source of methane. In North America and Europe, the largest single source of methane comes from landfills. The largest source of natural methane comes from wetlands.
CO2 is blamed for global warming yet the paleoclimate records show there is no correlation.
You seem to know a lot. So maybe you could then find me a single proper paper appearing in a real peer reviewed scientific journal in the last decade that says CO2 isn't to blame for global warming.
If you're going to spout off about how increasing CO2 emissions isn't a problem when the rest of the world thinks it is you could at least provide a link to your nonsense you're trying to pass as fact.
All you did was spout excuses - as far as I could make out, the only substantive thing you were saying was that they couldn't predict weather %100 accurately, therefore we shouldn't be predicting climate change over ~30 years. And, global warming aside, carbon dioxide is the cause of the greenhouse effect. So, we'd be screwed without it. However, with too much, more heat is trapped... it is a pretty logical "assumption", and I don't see why it's blowing smoke.
Weather forecasts are pretty accurate. And these global warming predictions are even less specific to area. All you should have to do to be scared is realize that: 1) higher CO2=higher temperatures (the greenhouse effect) and 2) it takes several years for changes on the surface to propagate into the upper atmosphere.
So, we pump CO2 into the atmosphere, and even if it was possible to stop emissions tomorrow, it would still take ten years for those changes to take effect.
I guess what I'm saying is: how would you like to find out (through experience) that global warming existed when your house was flooded by melting polar ice caps, and know that you still had ten more years of worsening conditions?
I have developed a truly marvelous proof of this comment, which this signature is too narrow to contain.
There is, of course, a vast difference between predicting weather - which is a local phenomena, with significant specificity - and predicting the climate trends - which is averaging general trends globally. Consider, for instance, that it is very hard to stand on a beach and predict the exact height and shape of the next wave and precisely where and when it will break. On the other hand predicting the approximate height and time of the next high tide is rather easier. GCMs are, indeed, currently rather poor at making predictions down to the level of day to day local weather. They have, however, been very accurate at predicting year on year global climate.
As noted above, contrary to your claim, the models have proved to be remarkably robust and accurate. They are also, contrary to popular perception in some circles, not just a big pattern matching machine that are "trained" on past data. They are models that are fed in physics. Yes, there are some tweakable parameters, as there should be in any model where there is some uncertainty. The greatest area of uncertainty in models currently is clouds, since they can be both a positive or negative feedback depending on the exact nature of their formation. Of course this problem is taken very seriously and there is a lot of study. The last IPCC report had considerable detail summarising that work. The simple reality, however, is that the models have worked pretty well, and have, in fact, made significant predictions that have since been observed.
Historical temperatures from ice-cores are determined by ratios of hydrogen or oxygen isotopes in the ice. The guts of the issue is that when combined in water the different isotopes, being different masses, fractionate out at slightly different temperatures, thus the exact isotope ratio is a function of many things, but a very signficant factor is the prevailing temperature at the time the water became vapout before precipitting out. Thus the ratio, while not an exact indication of specific temperatures (unless the many other factors are also accounted for), is a good indicator of general temperature trends over long time scales. For more detail see here. The result is that, using ice cores, we can plot temperature and carbon dioxide independently.
Furthermore, more recent temperature reconstructions (as in reconstructions of only the past 1000 years or so) rely not on ice cores but on a wide variety of sources including coral, tree rings, glaciers, and more. Usually many of these different methods are cross referenced with each other to create any single reconstruction. The results can be seen in this plot of 10 different reconstructions by different independent teams. The results, as you can see, while different, all show the same trend. If you're still uncertain, feel free to use the
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This is not good news because if people think that the problem is not serious enough to warrant attention, society will not change its bad habits.
Unless, of course, the problem wasn't serious enough to warrent attention in the first place, as many environmental skeptics have been saying all along.
"First of all the sun remains constant." completely wrong. the sun is NOT CONSTANT. it's ouput varies wildly with solar flares and obviously with the seasons and other solar cycles. "
I meant that when you are considering the sun it's effects on the oceans and the irrigation areas constant.
"AGAIN you couldn't be more wrong. evaporation has nothing to with with depth, and everything to do with SURFACE AREA, of which the ocean clearly dwarfs our irrigation."
It has to with the temprature. Shallow waters heat up faster and evaporate faster. Furthermore a lot of irrigation is done by spraying water from sprinklers which also evaporates at a much higher rate then the ocean.
About the surface area. Yes the ocean has more surface area but that's not the point. If there was no irrigation then the water vapor would be less. Agriculture adds a tremendous amount of water vapor into the air that would not be there otherwise. As I said virtually every square inch of land that can be cultivated is being cultivated. Sure it's less then the oceans which cover 75% of the planet but it's a significant chunk of the remaining 25%.
But hey don't let common sense get in the way. Just ignore the fact that agriculture puts water vapor into the air.
evil is as evil does