National Geographic "The War On Science"

GW = weather, and weather is extreme today, so GW is real.
Even if there has been more extreme weather in the past , before any rise in CO2.
There is greater polar ice today than there has been for decades.
More polar ice today than when CO2 was 30% lower circa the 1900s.

 

Mojo @57 – the world is warming? Do I understand you correctly? Every decade since the 1960’s, or by some other metric?


The other trends mentioned through time are also interesting. The Maue website (that both Mojo and I have mentioned before) does not show any change in global “accumulated cyclone energy” from 1972 to the present. He published a paper in Geophysical Research Letters discussing an apparent decrease in cyclone frequency (Maue 2011), but total energy matters more, being the source of storm surge and knocking things down. I am entirely confident that Dr. Maue would agree, as his website is the only place where one can find global ACE time series. The calculations are not trivial. He does them for some reason.


The Dai (2013) study saw recent increases in global drought area and severity. Sheffield et al. (2012) suggested that drought was not increasing, that the commonly used metric (called PDSI) should be replaced, and that the issue needed more study. What Sheffield et al. did not say was that drought was decreasing. Rather, they began the abstract with their expectations of future drought increases.


There were decadal-scale increases in CO2 from forest burning 1960-2000 (Schultz et al. 2008), but no detectable trend from 2001 to 2010 (Randerson et al. 2012). Global forest burn is another thing that only became directly quantifiable in the satellite era. Charcoal (burned trees) does persist in soils and you can determine when it burned from carbon-14 over the past 50,000 years or so. Such a global picture has been developed for only the last 2000 years (van der Werf et al. 2013). I could post their Figure 1, but this is an open-access journal, so DIY. It is a bit of a hockey stick though, I must say. Gradually downwards until about 1700 AD, then ka-boom.


It is only the wood-burning trend that I follow, other than from stimuli that I receive here, so thanks, again. I’d “like” #57, but with the invocation of BS it looks too much like scoring an “own goal”.


In all cases that I know, projections from global circulation models are for all those things to increase. Such models are what they are, and less canny than we’d hope. The recent decades look pretty flat, due at least in part to the high degree of interannual variability in the Earth system. Yet arguing from that, that all three are clearly trending down seems imaginative at best. But we have heard it at PC before and I have little doubt we’ll hear it again. Imaginative and dedicated.


+++


Dai, A. (2013). Increasing drought under global warming in observations and models. Nature Climate Change, 3, 52-58


Maue, R. N. (2011). Recent historically low global tropical cyclone activity. Geophysical Research Letters, 38, L14803, DOI: 10.1029/2011GL047711.


Randerson, J.T., Chen, Y., van der Werf, G.R., Rogers, B.M. & Morton, D.C. (2012). Global burned area and biomass burning emissions from small fires. J. Geophys. Res., 117, G04012, DOI: 10.1029/2012JG002128


Schultz, M.G.., Heil, A., Hoelzemann, J.J., Spessa, A., Thonicke, K., Goldammer, J.G.., et al. (2008). Global wildland fire emissions from 1960 to 2000. Glob. Biogeochem. Cyc., 22(2), GB2002, DOI: 10.1029/2007GB00303


Sheffield, J., Wood, E.F. & Roderick, M.L. (2012). Little change in global drought over the past 60 years. Nature, 435-438.


van der Werf, G.R., Peters, W., van Leeuwen, T.T. & Giglio, L. (2013). What could have caused pre-industrial biomass burning emissions to exceed current rates? Clim. Past, 9, 289–306.

 

excuse my off topic / word nazi-ism's - and I might be wrong - but i think that's 'inextricably' linked ... either way - they're stuck together

.

 

I sometimes think of what my response might be to someone who 'makes light' of climate change or AGW. If they say something around me like 'ah, climate change, global warming ... bunch of BS', my response could be something like ' oh wow, you're a Climatologist! Can I have your autograph, you must be soo smart!'

Seriously, to live in a world and enjoy so many things that have come out of science and technology like - Aeronautics/Space, Computers / Software, High Technology, Medicine/Healthcare/Pharmaceuticals , etc.... then pooh poo the work of bodies of scientists (IPCC, NOAA, etc ...) ... it's sickening really.
I can see the motive of business and politics to deny AGW: Money. Lots of money yet to be made burning fossil fuels.

But know nothing individuals 'tritely' blowing off AGW based on their know noting friends (trbves) beliefs ... PATHETIC. Let them be the first to be sent to another planet or to live in space, etc..

 

It actually is quite intersting as businesses, especially insurance companies are far ahead of the deniers.
Between the studies and outlook the insurance companies and risk assessment (Google "Risky Business climate change") business is starting to try to asses the dangers.
The armed forces have also added climate change to their largest risks for world stability.

It is becoming more and more apparent, even if you aren't a scientist that the risks are rapidly growing and the costs of dealing with it will only go up the longer we delay.

 

IIRC in the last 2 interglacials the sea level rose another 6 meters and ghg levels were lower than today. Man did not "cause" the last 2 interglacial sea level rises. While it is likely man is sped up the sea level rise, no one understands how to stop it.

Nature can be quite dramatic without man's help.

Huge icebergs are washing up on Cape Cod shores after winter blizzards

 

during mid-pliocene warm period Greenland was 18-27F warmer than it is now, so what?

Issue isn't that we are warming; issue is that we are warming quicker then it ever happened before. It would be great if the mechanism which were causing rapid warming/cooling/glaciation in last .5mil are able to accommodate man-caused GW, but if not? Is possibility of runaway process ruled out?

Ice age - Wikipedia, the free encyclopedia

 

Right. Also that there are a few more humans on the planet than during the Pliocene and their food supply is a whole lot more tenuous.

No one disputes the historical record that natural cycles have eclipsed present day AGW. That, however, is completely besides the point.

 

I found graphs @ 73 and 74 both to be informative, and will add another from "globalwarmingart.com"


This top panel indicates that CO2 has increased, something like exponentially throughout the 1880 to present time, including the two 50-year excerpts. Global air T did not. The most we could say is that it increased linearly, with a great deal of short-term variation.

This makes sense upon realizing that energy absorption depends on the logarithm of the gas in question. I think y'all have got that, whether from Beer's law or the idea of a fixed effect on temperature for each CO2 doubling.

The difficulty with message 73 is the implication that CO2 only increased in the more recent 50-year slice. Clear that up in your minds, and all three figures are singing the same song. This is as we would expect examining data and a reasonable causative mechanism.

So, no war on science here. Just one minor, ill-chosen implication that might stand between us and that song.

 

As the graphs I posted ended in 2000, we should further realize that the most recent Scripps Mauna Loa CO2 annual average (through 2015 Jan) is 399. Fossil fuel burn In the units of the bottom panel I posted was 10 in 2014. So these exponential increases are still underway.

 

Cyclo, during Pliocene, Greenland may have been ice-free, Antarctica certainly was not, and sea level was several meters higher than now. That would be a fair beginning on "so what?"

Concerning fastest ever T rise I post another figure from the Smith et al 2015 I recently prattled on about in "Climate Change News". Here comes the spaghetti:



This is temperature decadal rate of change for latest 1000 years. The recent past has been fast, but not clearly unique among the last 100 decades. Further back in time, the T proxies are not as sturdy. Could get better; a lot of polar ice cores are in freezers and techniques are improving to slice them more finely.

The aspect of Smith I talked about in that other thread is that climate models (going forward) project decades with + 0.4 oC, but the thermometers are still stuck in the + 0.2 range. So the 21st century ending 2 oC higher than now does not seem unlikely to me. A new perspective for me (but who cares?).

Given that, and given that the fossil-C burn enthusiastically continues, maybe we can direct our attention to walling off rising seas, getting enough water to crops, and ensuring (somehow) that the food chain holds in acidifying seas because all that protein is handy too. Environmental issues related to fossil-C extraction and medical consequences of smokin' them.

In short, it would be great if Thermageddon could be moved to the back burner because there are plenty of other aspects of adaptation/mitigation.

Let us not be simplistic in efforts to understand the Earth System, because it is really and truly, all we've got.

Let us not be slow to supplement fossil-C energy with renewables, because a few more terawatts would come in real handy. And would not make worse the issues in the "Given that" paragraph above.

I wish to avoid a world where in retrospect, people wonder "why did those dopes spend all their time arguing about temperature?". Because 'the room holds several elephants', and T may not be the biggest one.

Declare Peace on Science, and get on with it. 600 ppm CO2 is on the way. What will that require of us?

 

A note to clarify. 'direct' burning of fossil-C was 9.7 Pg in both 2013 and 2014. This flatness is a matter of interest in some news media now. Getting to 10 Pg requires inclusion of things like making concrete.

 

Yes the skeptics that look at the science simply don't believe (faith is not scientific) that is has to be catastrophic and that feedback is purely positive, as the earth has some pretty big negative feedback pathways. No feedback would have a sensitivity of 1 degree C per doubling of ghg (carbon dioxide, methane, etc). That seems low, as consensus appears to be 3, but there are great arguments that it is much lower than 3. 0.2/decade is not a floor then. If the sensitivity is 1, we are today at 401. Over the next century it is likely to stay bellow 802 (a doubling) so i would put the floor at around 0.7 for the whole century. The ceiling is the scary place as we have hit tipping points in the past, and even if sensitivity is low we may hit this ad eaily rise 4 degrees in the next centrury, worse if sensitivity is higher. 0.2 C/decade doesn't seem like a batd hypothesis. Lets look back in 20 years and see how it does.

I would use both concreaste and agricultural soruces. Both lead to deforestation which leads to less ability of the earth to sequester, so they may have a multiplier effect compared to simply burning the fuels for transportation or for HVAC.