Which IPCC Scenario is your guess?

[2020hindsight]

Which of the IPCC Scenarios do you think we should be using?

(based on public awareness, attitudes, likely fuel sources, population growth, technology improvement, (cleaner and more resource efficient maybe?) human efforts to reduce the effect , coordinated global effort etc)...

Note , you'll have to do some reading of the websites for this one - most of which I have pasted below

I suspect you could ask this as :-
"how ecologically friendly, frugal, fossil-fuel-dependant, and coordinated in our efforts do you see "mankind-en-masse" being in the (near) future and for the rest of the 21st century?"

Best estimate for Surface air warming in the 21st century:
B1...........1.8deg
A1T............2.4degC
B2..............2.4degC
A1B................2.8degC
A2.....................3.4degC
A1F1..........................4.0degC


http://en.wikipedia.org/wiki/Special_Report_on_Emissions_Scenarios

The Special Report on Emissions Scenarios (SRES) was a report prepared by the Intergovernmental Panel on Climate Change (IPCC) for the Third Assessment Report (TAR) in 2001, on future emission scenarios to be used for driving global circulation models to develop climate change scenarios. It was used to replace the IS92 scenarios used for the IPCC Second Assessment Report of 1995. The SRES Scenarios were also used for the Fourth Assessment Report (AR4) in 2007.

The six families of scenarios discussed in the IPCC's Third Assessment Report (TAR) and Fourth Assessment Report (AR4) are A1FI, A1B, A1T, A2, B1, and B2.

Scenario descriptions are based on those in AR4, which are identical to those in TAR. [1]

A1F1
The A1 scenarios are of a more integrated world. The A1 family of scenarios is characterized by:

Rapid economic growth.
A global population that reaches 9 billion in 2050 and then gradually declines.
The quick spread of new and efficient technologies.
A convergent world - income and way of life converge between regions. Extensive social and cultural interactions worldwide.
There are subsets to the A1 family based on their technological emphasis:

A1FI - An emphasis on fossil-fuels.

A1B - ditto , but with A balanced emphasis on all energy sources.

A1T - ditto, but with Emphasis on non-fossil energy sources.

A2
The A2 scenarios are of a more divided world. The A2 family of scenarios is characterized by:

A world of independently operating, self-reliant nations.
Continuously increasing population.
Regionally oriented economic development.
Slower and more fragmented technological changes and improvements to per capita income.

B1
The B1 scenarios are of a world more integrated, and more ecologically friendly. The B1 scenarios are characterized by:

Rapid economic growth as in A1, but with rapid changes towards a service and information economy.
Population rising to 9 billion in 2050 and then declining as in A1.
Reductions in material intensity and the introduction of clean and resource efficient technologies.
An emphasis on global solutions to economic, social and environmental stability.

B2
The B2 scenarios are of a world more divided, but more ecologically friendly. The B2 scenarios are characterized by:

Continuously increasing population, but at a slower rate than in A2.
Emphasis on local rather than global solutions to economic, social and environmental stability.
Intermediate levels of economic development.
Less rapid and more fragmented technological change than in B1 and A1

Incidentally Estimates of temp increase and rise in sea level are as follows (21st century):-
http://en.wikipedia.org/wiki/IPCC_Fourth_Assessment_Report

Temperature and sea level rise for each SRES scenario family
There are six families of SRES Scenarios, and AR4 provides projected temperature and sea level rises for each scenario family for the 21st century.

1. Scenario B1
Best estimate temperature rise of 1.8 °C with a likely range of 1.1 to 2.9 °C (3.2 °F with a likely range of 2.0 to 5.2 °F)
Sea level rise likely range [18 to 38 cm] (7 to 15 inches)

2. Scenario A1T
Best estimate temperature rise of 2.4 °C with a likely range of 1.4 to 3.8 °C (4.3 °F with a likely range of 2.5 to 6.8 °F)
Sea level rise likely range [20 to 45 cm] (8 to 18 inches)

3. Scenario B2
Best estimate temperature rise of 2.4 °C with a likely range of 1.4 to 3.8 °C (4.3 °F with a likely range of 2.5 to 6.8 °F)
Sea level rise likely range [20 to 43 cm] (8 to 17 inches)

4. Scenario A1B
Best estimate temperature rise of 2.8 °C with a likely range of 1.7 to 4.4 °C (5.0 °F with a likely range of 3.1 to 7.9 °F)
Sea level rise likely range [21 to 48 cm] (8 to 19 inches)

5. Scenario A2
Best estimate temperature rise of 3.4 °C with a likely range of 2.0 to 5.4 °C (6.1 °F with a likely range of 3.6 to 9.7 °F)
Sea level rise likely range [23 to 51 cm] (9 to 20 inches)

6. Scenario A1FI
Best estimate temperature rise of 4.0 °C with a likely range of 2.4 to 6.4 °C (7.2 °F with a likely range of 4.3 to 11.5 °F)
Sea level rise likely range [26 to 59 cm] (10 to 23 inches)

Note that those rises in sea level have been "upgraded" since.

 

[2020hindsight]

I suspect you could ask this as :-
"how ecologically friendly, frugal, fossil-fuel-dependant, and coordinated in our efforts do you see "mankind-en-masse" being in the (near) future and for the rest of the 21st century?"

and (I guess) effective or otherwise even if we do act (one for the sceptics)

 

[Smurf1976]

Whichever scenario results from us burning everything we can get our hands on.

I'd be highly surprised if by the end of this century we hadn't burnt essentially all the conventional oil and natural gas (already done a bit over a half and a quarter respectively) and most of the coal too. Plus quite bit of unconventional fossil fuels - tar sands, methane hydrates etc.

IMO the debate is not seriously about how much CO2 we will ultimately add to the air. Nor is it about when in any meaningful sense - a few years here or there won't make much difference. It's about who adds it and from what use as far as I'm concerned.

The more I've studied the topic over the past 20 years, the more convinced I've become that we'll collectively (globally) burn the whole lot as fast as we can get it out of the ground. Sad but I think that's what's going to happen without a very major shift in global politics, religion etc which is unlikely until there is an actual catastrophy or massive evidence that it's imminent - but then it's too late.

The only real thing that might change IMO is if peak oil or some other factor causes enough economic problems that we also end up using less gas and coal. Possible though we're talking about a pretty serious economic collapse here and not just a recession. Even then we'll try and burn our way out of it until we can't (because there's nothing left to burn).

 

[2020hindsight]

1. Whichever scenario results from us burning everything we can get our hands on.

2. I'd be highly surprised if by the end of this century we hadn't burnt essentially all the conventional oil and natural gas (already done a bit over a half and a quarter respectively) and most of the coal too. Plus quite bit of unconventional fossil fuels - tar sands, methane hydrates etc.

3. IMO the debate is not seriously about how much CO2 we will ultimately add to the air. Nor is it about when in any meaningful sense - a few years here or there won't make much difference.

4. It's about who adds it and from what use as far as I'm concerned.

5. The more I've studied the topic over the past 20 years, the more convinced I've become that we'll collectively (globally) burn the whole lot as fast as we can get it out of the ground. Sad but I think that's what's going to happen without a very major shift in global politics, religion etc which is unlikely until there is an actual catastrophy or massive evidence that it's imminent -

6. but then it's too late.

7. The only real thing that might change IMO is if peak oil or some other factor causes enough economic problems that we also end up using less gas and coal.

8. Possible though we're talking about a pretty serious economic collapse here and not just a recession.

9. Even then we'll try and burn our way out of it until we can't (because there's nothing left to burn).

brilliant post Smurf. (imho lol)
gotta be worth at least :4 twocents


I agree those scenarios are a bit confusing at first sight.
IPCC = Institute for Pointing out Cataclismic Conseqences?
IPCC = Institute for Promoting Climatic Caution?
IPCC = Institute for Pushing Complete Confusion? lol -

1. "whichever assumes burn burn who cares".
My guess is that's somewhere south of A1F1 - except that when the fossil fuels run out , then voila, problem turns around (for those still around). This is the only subcategory that specifically mentions continued fossil fuel use/abuse.
They don't give you an A2F1 option for example, which would be worse obviusly.

Just discussing and trying to understand those categories....

the B's are "best" options (at risk of confusing even more) -
more ecologically friendly than the A's
integrated world wide plan (B1), or more local and uncoordinated (B2), arguably half or 3/4 hearted

population magically halts at 9 billion (B1) or keeps growing (B2)

reductions in "material intensity" (and hence economic devt??) (B1), or "intermediate economic devt" (B2), arguably half or 3/4 hearted (B2)

emphasis on clean technolgies (B1), arguably half or 3/4 hearted (B2)

...........
Then for the A's - the same except less green mean approach. Now A1, like B1, assumes an integrated world wide plan, but (compared to B1) no real change in direction of economic growth. The same assumptions

coordinated (A1) and uncoordinated (A2), arguably 1/4 or half hearted (?)

population magically halts at 9 billion (A1) or keeps growing (A2) - even more rapid than B2

reductions in "material intensity" (i.e. "more convergent" economic devt) (A1), or "more selfish" (B2), arguably 1/4 or half hearted (A2)


Plus subcategories for A1 (? why not for each and every).
A1FI - An emphasis on fossil-fuels.
A1B - A balanced emphasis on all energy sources.
A1T - Emphasis on non-fossil energy sources


2. "I'd be highly surprised if by the end of this century we hadn't burnt essentially all the conventional oil and natural gas"...
unless we wake up to ourselves. But it surely means we MUST go nuclear eventually - whether 2050 or 2100 or whatever.

3. I'd say , since we are hotter today than yesterday - and the yesterday before that, then do something now today (so that tomorrow we will have a tomorrow? and another tomorrow after that?)

4. "It's about who adds it and from what use as far as I'm concerned." spot on!! While the third world dies in their deserts, and the islands get flooded, We argue about whether we are entitled to set air conditioned "controlled environs" in our massive shopping malls at (if anything) too cold - should be legislated try 29 degC (just hooking into the "temperate twenties" - or turn em off imo.

5. "or massive evidence that it's imminent" - surely we are there !

6. "but then it's too late" yep, but better late than baked.

7. shift in economic thinking you reckon?

8. "Possible though we're talking about a pretty serious economic collapse here and not just a recession." - probably true, different direction doesn't have to mean nothing to sell imo. Stern report more upbeat about the effects of changing direction - in fact pointing out the economic folly of NOT doing so etc.

9. "Even then we'll try and burn our way out of it until we can't (because there's nothing left to burn)." - I suspect you're right . (especially USA - no one tells them what to do!)

Thanks m8.
As I say - I reckon your scenario qualifies as A1F1 - but much worse. A2F1? 5degC?

 

[2020hindsight]

Think I'm right here, but this is what the graph would look like - approx for A2 (3.4deg C for the century) - just to put such rises into perspective

 

[Garpal Gumnut]

and (I guess) effective or otherwise even if we do act (one for the sceptics)

For those of us not into doom and gloom, or burn n squirm, from the postings, what does IPCC stand for?

gg

 

[2020hindsight]

http://www.metoffice.gov.uk/research/hadleycentre/models/modeldata.html

Hadley Centre (=UK Met bureau) projections..based on scenario A1B = "This is a 'business as usual' scenario, which assumes mid-range economic growth but no measures to reduce greenhouse-gas emissions."

(??Wiki calls A1B balanced between fossil and clean power (?) - hardly call that "no measures" !! - whatever)

Hopefully we will intervene and do better than A1B. (?)

Climate change projections
Key results from climate-change experiments conducted using Hadley Centre computer models of the climate system. The experiments assume that future emissions of greenhouse gases will follow the IS92a scenario, in which the atmospheric concentration of carbon dioxide more than doubles over the course of the 21st century. This is a 'business as usual' scenario, which assumes mid-range economic growth but no measures to reduce greenhouse-gas emissions.

It is important to be aware that predictions from climate models are always subject to uncertainty because of limitations on our knowledge of how the climate system works and on the computing resources available. Different climate models can give different predictions.

Climate change results from the Met Office Hadley Centre
The globes below show latest results from the Met Office's climate change research. The data are based on a mid-range IPCC emissions scenario A1B.

If you click on the map of the world it passes through the century with temp effects.

btw bright red on that graph = +15degC from 2000 I think

 

[2020hindsight]

For those of us not into doom and gloom, or burn n squirm, from the postings, what does IPCC stand for?

gg

http://en.wikipedia.org/wiki/Intergovernmental_Panel_on_Climate_Change

Thanks for that gg - at last I found an easy table that shows those scenarios

 

[Garpal Gumnut]

Thanks.

I've voted bang in the centre, so far its a normal distribution. People are averse to bad predictions. I do know the Antarctic is supporting less ice than in the past. Global temperature is a difficult one to predict. Any statisticians in the thread?

gg

 

[2020hindsight]

http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr_spm.pdf
IPCC's 4th report (2007)

 

[Gundini]

2020, unbelievable thread, and info/pics/data, it's a credit to you.

Just one question!

What's the question again?

 

[wayneL]

Weather is a chaotic system (in the physics sense). Even a negative result is possible.

BTW, why isn't the most important GW gas ever mentioned?

 

[visual]

Think I'm right here, but this is what the graph would look like - approx for A2 (3.4deg C for the century) - just to put such rises into perspective

One question what caused the warm age and the mini ice age?
Today the blame goes to burning oil and coal but in medieval times what was the cause and then what caused the mini ice age?

 

[2020hindsight]

Gundini
Well, when it comes to predicting what the temp will be in 2100
It is necessary to make some assumptions about what will be done to coordinate man's efforts internationally, will there be an economic or environmental emphasis, what will the population be etc ....

Hence there are various scenarios in the IPCC report.

btw, here is the graph of world temp for the last 3000 years. (approx only)
and what would happen if it went up 3.4degC for instance (scenario A2).

The "more median" option (A1B) is only 2.8degC, but still pretty serious yes?

To me that suggests that we should check it out .... to the best of our ability.... and change our ways bigtime if necessary.

Perhaps in the course of each of us researching those scenarios we will be better equipt to decide on GW issues

Note the blue line for A1F1 - my guess is the only reason it changes direction is that we run out of fossil fuels - could be the only thing that saves a fraction of the species on earth - and us (as Smurf alluded to)

the coloured graph is from the IPCC report - the other I just found somewhere (and very approx for 2007 temp, post hockey-stick)
http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr_spm.pdf

PS I have revised the 3000 year graph downward - no need to risk being accused of exaggeration

 

[2020hindsight]

Weather is a chaotic system (in the physics sense). Even a negative result is possible.

BTW, why isn't the most important GW gas ever mentioned?

well that IPCC report mentions most gases (anthropo-thingo)
- in terms of CO2equivalent.

 

[wayneL]

well that IPCC report mentions most gases (anthropo-thingo)
- in terms of CO2equivalent.

Exposes IPCC intentional muppetry.

The most important GW gas is H2O vapour.

 

[2020hindsight]

One question what caused the warm age and the mini ice age?
Today the blame goes to burning oil and coal but in medieval times what was the cause and then what caused the mini ice age?

visual,
There are other parameters which affect the earth's temperature. Solar actvity (heats), volcanic dust (cools) etc. btw, future contributions of all known parameters - with best guess on their trends - have allegedly been taken into account in predicting into the future.

 

[2020hindsight]

Exposes IPCC intentional muppetry.

The most important GW gas is H2O vapour.

again wayne, play riddles if you wish
not much we can do about water vapour.
(that graph was anthropogenic)

but short of drinking less confused I'd prefer to do what you do - and act on the co2 and other pollutants.
plus, btw, vote for people who will take it to the international community.

 

[wayneL]

again wayne, play riddles if you wish
not much we can do about water vapour.
(that graph was anthropogenic)

but short of drinking less confused I'd prefer to do what you do - and act on the co2 and other pollutants.
plus, btw, vote for people who will take it to the international community.

Riddles? **** me! It's a huge part of the whole climate equation and goes to the total effect of other gases.

 

[2020hindsight]

Riddles? **** me! It's a huge part of the whole climate equation and goes to the total effect of other gases.

sure - any large molecules - H-O-H, O-C-O , CH4, etc cause ghg effect.
where O2 doesn't for instance.

- so what are you planning to do about water vapour. ?
I mean what's your point here?