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Is Climate Change Just A Lot Of Hot Air?

bcglorf says...

@newtboy

#1 and #2, fine, if you won't go there to read it's now pasted in full for you:
Arctic tundra soils serve as potentially important but poorly understood sinks of atmospheric methane (CH4), a powerful greenhouse gas1, 2, 3, 4, 5. Numerical simulations project a net increase in methane consumption in soils in high northern latitudes as a consequence of warming in the past few decades3, 6. Advances have been made in quantifying hotspots of methane emissions in Arctic wetlands7, 8, 9, 10, 11, 12, 13, but the drivers, magnitude, timing and location of methane consumption rates in High Arctic ecosystems are unclear. Here, we present measurements of rates of methane consumption in different vegetation types within the Zackenberg Valley in northeast Greenland over a full growing season. Field measurements show methane uptake in all non-water-saturated landforms studied, with seasonal averages of − 8.3 ± 3.7 μmol CH4 m−2 h−1 in dry tundra and − 3.1 ± 1.6 μmol CH4 m−2 h−1 in moist tundra. The fluxes were sensitive to temperature, with methane uptake increasing with increasing temperatures. We extrapolate our measurements and published measurements from wetlands with the help of remote-sensing land-cover classification using nine Landsat scenes. We conclude that the ice-free area of northeast Greenland acts as a net sink of atmospheric methane, and suggest that this sink will probably be enhanced under future warmer climatic conditions.

#3, regardless of if it make's sense to you, and regardless of if it means a 10C warming by 2100, the IPCC scientists collaborative summary says it anyways. If you want to claim otherwise it's you opposing the science to make things seem worse than they are, not me.

#4, To tell them those things would sound like this. The IPCC current best estimates from climate models project 2100 to be 1.5C warmer than 2000. This has already resulted in 2000 being 0.8C warmer than 1900. Summer arctic sea ice extent has retreating significantly is the biggest current impact. By 2100 it is deemed extremely unlikely that the Greenland and Antarctic iccesheets will have meaningfully reduced and there is medium confidence that the warming will actually expand Antarctic ice cover owing to increased precipitation from the region. That's the results and expectations to be passed on from the 5th report from an international collaboration of scientists. Whether that fits your world view or not doesn't matter to the scientific evidence those views are founded on and supported by.

You said the ocean's may be unfishable in 20 years, and the best support you came up with was a news article quote claiming that by 2040 most of the Arctic would be too acidic for Shell forming fish. Cherry picked by the news article that also earlier noted that was dependent on CO2 concentrations exceeding 1000ppm in 2100, and even that some forms of plankton under study actually faired better in higher acidity in some case. In a news article that also noted that the uneven distribution of acidity makes predicting the effects very challenging. If news articles count as evidence I then want to claim we'll have working fusion power to convert to in 5 years time from Lockheed Martin. I'll agree with your news post on one count, the world they talk about, where CO2 emissions continue accelerating year on year, even by 2100, is bad. It's also a bit hard to fathom with electric cars just around the corner, and if not solar and wind, fusion sometime before then too, that we'll still be using anywhere near today's emissions let alone still accelerating our use.

by 2025 it's estimated that 2/3 of people worldwide will live in a water shortage.
And you link to a blog, and a blog that provides exactly zero references to any scientific sources for the claim. Better yet, even the blog does NOT claim that the access to water will be limited because of climate change, the blog even mentions multiple times how other forms of pollution are destroying huge amounts of fresh water(again with zero attributions).

Here's the IPCC best estimates for 2100 impacts regionally:
http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter14_FINAL.pdf

You'll find it's a largely mixed bag if you can be bothered to read what the actual scientists are predicting. Just bare in mind they regularly note that climate models still have a lot of challenges with accurate regional estimates. I guess your blogger isn't hindered by such problems though. If you don't want to bother I'll summarize for you and note they observe a mixed bag of increased precipitation in some regions, notably monsoons generally increasing, and other areas lowering, but it's all no higher than at medium confidences. But hey, why should uncertainty about 2100 prevent us from panicking today about more than half the world losing their drinking water in 10 years. I'll make you a deal, in ten years we can come back to this thread and see whether or not climate change has cause 2/3 of the world to lose their drinking water already or not. I'm pretty confident on this one.

Northern India/Southern China is nearly 100% dependent on glacial melt water, glaciers that have lost 50% in the last decade
Lost 50% since 2005? That'd be scary, oh wait, you heard that from the same blog you say? I've got a hunch maybe they aren't being straight with you...
Here are a pair of links I found in google scholar to scientific articles on the Himalaya's glaciers:
http://cires1.colorado.edu/~braup/himalaya/Science13Nov2009.pdf
I you can't be bothered to read:
Claims reported in the popular press that Siachin has shrunk as much as 50% are simply wrong, says Riana, whose report notes that the glacier has "not shown any remarkable retreat in the last 50 years" Which looks likely that your blogger found a popular press piece about that single glacier and then went off as though it were fact, and across the entire mountain range .

http://indiaenvironmentportal.org.in/files/glaciers%20and%20climate.pdf
Here's another article noting that since 1962 Himalayan glacier reduction is actually about 21%.

If you go back and read the IPCC links I gave earlier you can also find many of the regional rivers and glaciers in India/East China are very dependent on monsoons and will persist as long as monsoons do. Which the IPCC additionally notes are expected to, on the whole, actually increase through 2100 warming.

I've stated before up thread that things are warming and we are the major contribution, but merely differed from your position be also observing the best evidence science has for predictions isn't catastrophic. That is compounded by high uncertainties, notably that TOA energy levels are still not able to be predicted well. The good news there is the latest IPCC estimated temps exceed the observed trends of both temperature and TOA imbalance, so there's reason for optimism. That's obviously not license for recklessly carrying on our merry way, as I've noted a couple times already about roads away from emissions that we are going to adopt one way or another long before 2100.

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