As I am traveling and do not have time to respond to the different posts, I will reply to Csnavywx as I agree that cumulative emissions and not rates are what counts. The first attached image by the IEA is a little bit old (it is what I have when traveling) compares the 1990 - 2011 cumulative CO2 emissions vs the AR4 SRES scenario (see the second figure as to how to compare SRES and RCP scenarios). The IEA figure shows the historical dip in CO2 due to the 2008 financial crisis (show one does need to be careful about variability (due to various factors including economics, ENSO, plant growth variations etc.) But even considering the variability, the evidence gives a high probability that we are more likely following the high end of the IPCC emission scenarios than the low end.
This is not only true for CO2 but also for almost all of the GHG atmospheric concentrations, as indicated for methane in the third attached image and for nitrous oxide in the fourth attached image (both showing the 2014 Mauna Loa data), as compared to the following mid-year RCP 8.5 (I take this to be the values on June 30th) of 1823.655 and 1837.966, for methane in 2014 and 2015 respectively, and of 326.17 and 327.01, for nitrous oxide in 2014 and 2015, respectively.
Again, I do not have a crystal ball, and I do not know what radiative forcing will happen in the future; but I believe that it is unwise to assume that we are not following a BAU pathway now, and that unless we make a real effort (such as carbon price) we may well remain on a BAU pathway for sometime to come.
You "believe" in it, huh. Well, unlike you, i don't "believe" in it; i _know_ it. And i know that even if real effort ("such as carbon price" and much more than that) will be made, - we'll still follow higher end of carbon emission scenarios, or even above.
It's rather simple logic and relatively few facts of life which leads to this conclusion. I'll present them for your consideration.
1. At this time and for at least several decades into the future, billions of humans on Earth each consume goods and services which are 1) critically important for their survival and b) can only be provided via burning hundreds kilograms or even tons of fossil fuels per capita per year. Example: modern food production requires fossil fuels (mechanization, fertilizers, transportation) to produce enough food to feed 7+ billions humans. There is NO other known method to produce that much food - not even third of it.
2. At this time and for at least few generations of people into the future, dominant consumption pattern - is "consumerism". Humans consume much more than they actually need. Example. They "like" meat, and billions of humans who can "afford" to eat meat every day - do so. They are not bothered about grain, water, pollution and other costs of growing beef and such. This is one direct consequence of "consumer culture" promoted in mass media, which, in turn, is one direct consequence of "free market competition" between large corporations (which have more than enough money and influence to design and use mass media "advertisements", including hidden and indirect ones).
3. There is the "tragedy of commons" and peer pressure. Majority of humans do NOT change to cleaner, less-polluting and less-carbon-intensive ways of life when a) it is not their property which suffers as a result of their anti-Gaia behavior, and b) majority of their peers are not doing it. This is a direct consequence of "private property" concept perpetuated by capitalistic societies. Defining what is "mine" automatically define what is "not mine", which leads to tragedy of commons. As long as capitalistic mindset prevail, this block will continue to be a major factor. Sadly, better (than capitalism) alternative is not known, so far; socialism proved time and time again to be only a dream, not realistically possible in practice (always get corrupted).
4. There is the "amplification of complexity and efficiency by prolonged use" phenomena in technologies. Best illustrated by example of internal combustion engine: by the time it was just invented - middle XIX century, was it, - it wasn't popular, or any efficient, or any complex. Steam machines ruled the world of large vehicles like trains and ships, and were much more complex than any internal-combustion engine of the time. Used and built in great numbers, steam engines grew much more efficient and complex simply because they were built and used in such great numbers: the latter fact caused so many engineers to invent and patent improvements for steam machines, so many technicians and operators to experiment and find better methods and regimes of operation, etc. And then, early XXth century, internal combustion engines, slowly developed bit by bit during previous decades and improved by visionaries like Diesel and Ford, went to be mass-produced and mass-used for smaller applications (cars, generators, etc). And once again, mere facts of being produced in great numbers, used by millions, - caused so much more innovation, invention and improvement to happen to internal combustion engines. Very soon, internal combustion engines became so much more refined, advanced and complex that they became more efficient than steam engines on trains and smaller ships. Plus, aviation was born. Internal combustion engines for all those vehicles had to differ dramatically between themselves, which further diversified the science of internal combustion engine, made them even more complex and efficient. Today, we have ICEs of all sorts, from tiny ones used in plane modelling sport - to huge diesel-electric submarine ones.
Similar effect, and on similar scale, is happening with fossil fuel extraction. Done for decades on a world-wide scale, dozens gigatons every year last few decades, - the science and engineering of fossil fuel extraction attracted lots and lots of talented eggheads and engineers. They enhanced the technology further and further. The process is going on even now. Shale oil and gas, nearly a dozen of non-traditional methods of oil extraction from once rich, but nowadays nearly "exhausted" sources, very sophisticated oil and gas finding methods, etc etc. Platforms at sea, several-kilometers-deep holes into the ground. All those things are very complex and require massive amount of science and development. Which oil and gas and coal businesses get - they have the scale and the pay to afford it. So it's kind of promotes itself, R&D happens dozens to hundreds times faster for fossil fuels than it ever was for alternative fuel sources. And this situation will remain as long as fossil fuels power over 85% of the world (counting both electricity AND all sorts of other fossil fuel applications - plastics, chemistry, transportation, machine oils, asphalt, etc). That's why mankind _can't_ beat efficiency of fossil fuels; for every improvement of, say, solar-thermal electricity generation - there are dozens or hundreds of comparable efficiency improvements in fossil fuel power generation and/or fossil fuel extraction.
5. Infrastructure inertia and continuity. See, billions of people now own devices and/or vehicles which demand (primarily) fossil fuels as their energy source. Every time an average world citizen turns on his TV - he burns some coal and gas, since over 70% of the world electricity comes from burning those; every time someone drives his car - he burns some oil (or, for electric cars - some coal and gas, since it uses electricity primarily generated by oil and gas). Every time someone flies a plane, eats a burger (created and transported mainly with energy of fossil fuels), boils some rice (grown and transported with fossil-fuel-powered vehicles, - and boiled most likely by burning some fuel, as well), - list goes on and on. The key thing here - people _own_ things their lives depend on, and most of those things are designed to work from fossil fuel energy. We talk WHOLE WORLD infrastructure here, most of which is fossil-fuel based. It took more than a hundred years to build it. And most bits and pieces are someone's property. It is naive to expect people will willingly toss their property away; it is naive to expect much or most of this world infrastructure could be replaced by something much more complex (alternative energy is more complex, sadly, than simply burning fossil fuels) in less than another hundred years; and it is naive to expect mankind to function "somehow" without burning fossil fuels AND without having adequate infrastructure for functioning mainly from non-fossil energy source(s).
Conclusion. Facts above are more than enough, together, to clearly see that no carbon price, no amount of legislation, and even, no amount of "real effort" can prevent the world from following higher-end carbon emissions scenarios for at least few decades ahead. There are only two things which can prevent it. First, planetary catastrophe (global nuclear war; sudden and catastrophic collapse of much or most of Greenland ice sheet into the ocean, causing mega-tsunami around the world and several meters of nearly instant sea level rise; large asteroid hit; etc). Second - rapid, massive and global reduction of human populations, by an order of magnitude or so (i.e., down to 10% or less of current population - to 700 millions or below), which would mean unnatural death of most humans alive - be it unprecedentally powerful epidemic, or some organism genetically engineered to destroy most humans, or something else of the sort. Anything less will fail to alter mankind carbon emissions simply because most of mankind is now dependent so massively and critically on all the fossil fuel burning.
P.S. It is illuminating to compare carbon emissions graph (since 19th century to nowadays) with world population graph. In a sense, fossil fuels are nothing less than a lifeblood of modern mankind. It can no less reduce fossil fuel burning than a human could reduce volume of blood in his system; yes, _some_ reduction can be done, - and if really desperate, even rather large reduction, something on the order of 50%, i.e. reducing it to half, - but anything much more than that leads to death - for both human body if we talk blood, and for mankind if we talk fossil fuels. The task of switching to alternative energy source for mankind is akin to switching to some GREEN blood for human body, - means, different blood cells, different compound which carry oxygen to tissues, different bone morrow, different genes - and lots of them - for human being, and most likely lots of changes within all major organs and tissues of the body. That task is possible to do for intelligent beings working together long enough time - for both mankind and human body; the latter, can be altered by geneticists, but it'd take long time to create such a "green-color-blood human"; the former - quite similarly, takes lots of scientists and engineers working together for decades, creating alternative fuel sources (alternate electricity sources is not enough - different sort of fuel for planes, ships, buses, trucks, agriculture machinery, etc would also be needed), and then more decades to implement all the tech - to create billions of vehicles and devices to replace old ones, to pay for all that, to convince owners to change from old ones to new ones, etc. This is the ONLY way how it could actually work in practice, and no amount of carbon price will change it. Raising carbon price sky high "right now" - this year, or next year, or some time 2020 - will only result in millions of bankruptcies and billions of dead and hungry people worldwide, since there is no alternative infrastructure for vast majority of places and individuals yet; in fact, there is still even no alternative technology able to provide base-load power, nor globally-enough amount of non-fossil-fuel vehicle fuel. We don't even know - as a mankind, - _how_ exactly to replace our fossil-fuel-based infrastructure; we don't even know if it's actually possible at all. Still lots of years of R&D to do, here - and no guarantee of success. That's why we _need_ to recognize: we will continue higher-end carbon emissions path for several decades into the future at very least; we _will_ get consequences to it; we _will_ need to learn how to live with that. And it will be harder and harder to work on cleaner tech and infrastructure as things get progressively worse. There is nothing to "believe" in here - this all is already well _known_. It is just that so many people - especially in the media, - are willing and/or ordered to pretend this is not the case. Don't let them fool you. Think for yourself.