The Royal Soc and NAS have produced Climate Change: Evidence & Causes. From the official doc we have: The atmosphere and oceans have warmed, accompanied by sea-level rise, a strong decline in Arctic sea ice, and other climate-related changes. EWW says this in his quick intro (go on, its only 1:20, watch it) but he adds "...but so far, they are relatively modest, but if we continue emitting carbon dioxide without any abatement, the effects will get really large by the end of the century... we present this report as the state of the science as it is, the basis on which people - governments - the world as a whole - to decide: whether to do anything, what to do, whether to reduce emissions or whether to let them happen and prepare for the consequences".
I very much like this way of putting it, and its pretty well what I'd have said myself, particularly the last bit.
Browsing through the report - a sequence of Q&A's - it covers most of the ground you'd expect in about the sequence you'd expect.
Are climate changes of a few degrees a cause for concern?
Asks Q 17. And the answer is:
Yes. Even though an increase of a few degrees in global average temperature does not sound like much, global average temperature during the last ice age was only about 4 to 5 °C (7 to 9 °F) colder than now. Global warming of just a few degrees will be associated with widespread changes in regional and local temperature and precipitation as well as with increases in some types of extreme weather events. These and other changes (such as sea level rise and storm surge) will have serious impacts on human societies and the natural world.
which seems fair. Will it, and the rest, convince the "skeptics"? No, of course not, because they aren't open to argument, and because they likely won't read it anyway. Or, to be slightly fairer to those "skeptics" who are capable of rationality (not a large constituency, so largely ignored by all sides): whilst it does cover some of the problems ("Why is Arctic sea ice decreasing while Antarctic sea ice is not?") it only has the space to sketch in an answer, and it doesn't refer you elsewhere for more details.
Will it be read by interested observers, government folk, school children, those wishing to be informed? Quite likely. For those for whom the full weight of IPCC AR5 is too scary and complex, this is a decent simplification of the main points.
ZOMG are we all going to die?
Yes, of course, we will all die eventually. But not of GW. Or, more seriously, Are disaster scenarios about tipping points like ‘turning off the Gulf Stream’ and release of methane from the Arctic a cause for concern? gets:
Results from the best available climate models do not predict abrupt changes in such systems (often referred to as tipping points) in the near future. However, as warming increases, the possibilities of major abrupt change cannot be ruled out... Such high-risk changes are considered unlikely in this century, but are by definition hard to predict. Scientists are therefore continuing to study the possibility of such tipping points beyond which we risk large and abrupt changes.
Where I'd criticise the report is in the leading you on to further deeper reading. There's a list of sources at the very end - what you'd expect, IPCC AR5 etc - but they aren't really folded into individual sections, so anyone wanting to know more about any individual topic would then be faced with navigating AR5 for themselves, which is no easy task. They should have provided "further reading" and/or direct citations for each of the individual sections.
Oh, and I'll also criticise the lighting in the video. Will W, where were you? The light from the lamp needs to spill over Eric's face making him look like a kindly uncle, not on the wall leaving him in shadow like a ringwraith.
Quiet, sane voices from the RS and NAS warn us again that the house is on fire, while most of humanity continues to argue loudly about what color to paint the kitchen or whose job it is to vacuum the carpet.
At the moment, the problem is too remote to engage our attention. Perhaps we'll notice when the roof falls in.
@Adam R : +1. If you don't mind I am going to shamelessly rip that off and use it myself.
We have a long term aging world with a decelerating global economy, and outside of Africa, a declining population.
Kinda hard to imagine much increase in CO2 forcing rate under those circumstances.
@ #2 David :
Please, be my guest.
> hard to imagine much increase in CO2
The increase is not something you imagine.
It's something you know about.
Let's see: suppose we stabilize emissions tomorrow and they stay the same for the rest of the century, and we don't do CCS or any equivalent.
Does Mauna Loa-measured CO2 go up, stay the same, or go down?
re #7: Fairly sure atmospheric CO2 goes up still.
Ongoing climate change following a complete cessation of carbon dioxide emissions
Nathan P. Gillett et al.
Nature Geoscience 4, 83–87 (2011) doi:10.1038/ngeo1047
Let's try condensing that last quote a bit:
Results from the best available climate models do not predict abrupt changes in such systems...in the near future...[but] (s)uch high-risk changes are by definition hard [for the models] to predict.
Well, isn't that self-canceling.
My kingdom for a preview.
[Fortunately, I have special powers -W]
My kingdom for a preview.
Heh. I was in the habit of using RealClimate's comment preview for my comments here, until I accidentally posted my comment there instead of here. Since W has special powers, I guess I can live without a preview.
@ Adam R's no. 1
"At the moment the problem is too remote to engage our attention. Perhaps we'll notice when the roof falls in."
You know, I really hate seeing a good-comrade all in a funk--I really do! So I thought I'd try and cheer Adam up (and everyone else too, for that matter, who shares Adam's "quiet" and "sane" despair). Yep!--I've got an idea that will chase all those eco-flake, chicken-little, not-only-is the-sky-falling-but-now-even-the-"roof"-is-falling-in-too-thanks-to-the-headless-chicken-deniers-who-just-won't-heed-the-brave-new-hen-house-grand-designs-hatched-by-their-egg-head-betters!, worry-wart blues away, big-time. With me?
First off, all Adam's Cassandra-boogers aside, things are not really so bad on the carbon-reduction front, in reality. For example, the wiki entry for "Fuel Poverty in the United Kingdom" advises that approximately 25K useless-eater, point-source CO2-emitters are regularly and permanently shut down every winter since 2000. And even more encouraging, the 2008-09 freeze-your-butt-off-proof-of-global-warming Winter moved that carbon-reduction figure up a gratifying 23% to 38K.
Now, I can well anticipate that "some" will chide such numbers as mere, even depressingly small, drops in bucket. But bear with me--my idea takes the "excess winter deaths", seasonal-cull "ball" and runs with it.
My CO2-cidal plan has three elements:
-Gut the British economy through mind-numbing, stultifying regulation and carbon taxes/cap-and-trade permits, thus reducing much of the population (the hoi-polloi portion) to permanently-unemployed penury and dependence on government hand-outs controlled by hive-apparatchik gatekeepers. And, most critically, plunge, thereby, ever-increasing numbers of poor-sucker, coolie-trash nobodies into "fuel poverty". Beginning to get the picture?
-Dramatically ratchet up utility bills through regulation/carbon taxes (Whoa!-give me a chance to 'splain things before you start hurling your brick-bats my way, PLEASE!--my plan also takes care to increase wind-turbine, rentier income-flows to the hive's shot-caller class so that they more than offset any "sticker-shock" utility billings, and, also, my plan provides the hive's parasite courtiers, toadies, and enablers with exclusive, tax-payer rip-off, utility bill subsidies that will fully preserve their in-your-face, snout-in-the-trough, carbon-piggie hypocrite-lifestyles).
-Gut the "National Health Care" system through long waits for specialty care (google "Forbes happy birthday to great britain's increasingly scandalous health care service" for some "good news" on the hive's current, heroic efforts in this area); a Hogarthian standard of hospital-care (the wiki entry "Stafford Hospital Scandal" serves as the model here); and a quality of medical diagnosis/treatment that dispenses with the historic, anti-science, flat-earther, Republican-brain focus on the patient's welfare and, instead, replaces it with an enlightened view of medical care as a valuable instrument of "carbon-footprint-reduction" (again, see the above Forbes article, for some interesting developments, already, that might be of relevance on this score).
And, then, with those three elements, above, in place, it's all just a matter of a little patience until the next unusually severe winter works its carbon-reduction magic. Indeed, I'm thinkin' that with my plan locked-and-cocked, the next, humdinger cold-snap might even up the "hibernal thinning" body-count by two or more, Gaia-pleasing orders of magnitude, with any luck! Voila!
Happy now, Adam? And David H, please feel free to "shamelessly" rip-off my plan "and use it for yourself". And, naturally, I fully expect that my plan will be improved upon by Stoat's collective, smarty-pants brain-power, so be my guest, guys, with your "sane" and "quiet" adjustments to the basic scheme of maneuver.
[So: Mike is trolling. Your test, folks, is to not respond -W]
re #1: Reading the RS and NAS doc, I don't see a the house is on fire warning. Oh, for sure, there's some frayed wiring. There's too much lint in the dryer flue. and that space heater is dangerous, but there is still time. I think there is every reason to be optimistic about reductions in human CO2 emissions over the next 50 years.
[So: Mike is trolling. Your test, folks, is to not respond -W]
This is the internet
@ Paul Kelly #14:
Mmm, I think 400 PPM and climbing is a bit more of a problem than some frayed wiring: I can definitely smell smoke. But yeah, it's still manageable--just.
Unfortunately, all the voices shouting that there is no fire or, OK, there is but it's not a big deal, are drowning out the calls to the fire dept.
"...but so far they're relatively modest..."
As said by someone who lives in a place that lacks millions of acres lying less than 2m above sea level. For those of us who do this statement is infuriatingly dismissive.
[As a global statement, it can't address every little local difficulty. From your IP, though, I'm baffled. *So far* the affects of SLR on, say, the USA has indeed been relatively modest. Do you dispute that? -W]
All that the world needs to understand is why it's not carbon dioxide after all. The reasons are in my comments starting here and similar have been posted in this blog, but William deletes them probably because he feels threatened by them and that is because he cannot rebut the truth of physics.
[Spare me the paranoia. I've deleted no links to your comments elsewhere; you've never attempted to place that link before. My comment policy explicitly suggests that links elsewhere are better than repeating yourself. The rest, which is ranting, deleted -W]
*So far* the affects of SLR on, say, the USA has indeed been relatively modest. Do you dispute that? -W]
Why yes. When Eli was a little bunny growing up in NYC the south end of Manhattan seldom if ever flooded. The same is true for South Brooklyn. Today, well you saw what Sandy did.
Point is that even a small lift with a big heave makes a huge difference.
In the real world, phrases like "relatively modest" are about as useful as "catastrophic".
Yes, I dispute that. Much of the Gulf coast where I live has a 1,500:1 (horizontal to vertical) to 10,000:1 slope. This means that the beaches, barrier islands and marshes along this coast are already doomed with the 0.8m+ of sea level rise most experts agree we are already locked into. For this area, every additional year of CO2 accumulation adds to the slow motion disaster that is already playing out. The various sea level rise VS land inundation maps that have been produced for this area greatly underestimate land loss as they don't take subsequent erosion into account. In addition, because these are accretion features (beaches, barrier islands and marshes) that have built up over the last 6,000 years of near steady sea level, often with irreplaceable Pleistocene (fossil) sediments, in this area, they are a geologic legacy that won't be rebuilt inland, even if development patterns allowed, which they don't. Local subsidence from oil,gas and water withdrawal have provided examples of how these geologic features react to relative sea level rise so we're pretty sure of what's in store.
[Two answers. First, none of this has happened "already", though that might depend on what you mean; the forcings have happened, the inundation hasn't. Second, although locally being drowned isn't modest, on a global scale your little bit of the coastline is just a little bit of the coastline -W]
"Yes, I dispute that. Much of the Gulf coast where I live has a 1,500:1 (horizontal to vertical) to 10,000:1 slope. This means that the beaches, barrier islands and marshes along this coast are already doomed with the 0.8m+ of sea level rise most experts agree we are already locked into."
There is also salt intrusion into the porous limestone aquifers of the Florida Peninsula …
> [As a global statement, it can't address every little local difficulty. From your IP, though, I'm baffled. *So far* the affects of SLR on, say, the USA has indeed been relatively modest. Do you dispute that? -W]
Yes, only two cities have been affected so far - New Orleans and New York!
[NO wasn't SLR -W]
NO wasn't solely SLR, but 8" of SLR contributed to the miseries of Katrina, surely?
SLR has definitely played a part in the ongoing destruction of the Mississippi delta wetlands south of the city, reducing their effectiveness as a surge barrier, to say nothing of the massive loss of natural habitat for Gulf Coast plants and animals--and land for human settlements.
It should be noted that an infestation of marsh rats eat the roots of plants anchoring and matting the wetlands in place. David Brin ( Contary Brin ) has written articles on the folly of decades long dredging of the ships' channel in the Mississippi River as a cause of lack of silt deposit renewing the delta. Damage from Katrina was as much a failure of responsible upkeep of infrastructure holding back ravages of the sea as any actual storm surge. At the time it crossed the coast the storm actually had dropped force category to a lesser measure ! As a consequence of this failure, Levees.org was formed to spread awareness of these problems. Yet there is a stunning resemblance to measures possible under water warfare in this scenario : both Katrina and marshland.
Yes, the Delta is suffering from multiple abuses; dredging oil and gas service canals thru it has hurt as well. Piling SLR on top of all of it is not helping.
And yes, not everyone is happy with restoration efforts. Oyster fishermen have been outraged at some of the measures to increase the silt deposition in the area, because floods of fresh, muddy water can kill oyster beds. It all shows what a bad idea it is to mess with nature in the first place: we end up chasing our tails trying to correct the unintended consequences.