Yes, there is a rate of CO2 emissions from fossil fuels. There are all kinds of rates. That one is not the steepness of the curve either but its height. The higher the curve goes, the more CO2 emissions from fossil fuels happen in one year. That's not what we were talking about.
You might think that emissions rate translates into a proportional increase in atmospheric CO2 concentrations but thankfully it doesn't with a year on year increase of 1.6 ppm right now (according to the seasonally corrected Mauna Loa monthly mean). What exactly happens to emissions of fossil fuels is poorly understood except that a large share remains in the atmosphere. This share is fluctuating however and there is also considerable concern in some quarters about the unpredictability of CO2 sources other than fossil fuels.
But these are all details. The bottom line is that there's an increasing amount of CO2 in the atmosphere which can be traced to combustion of fossil fuels. Whatever happens to any rate at any one point, atmospheric CO2 concentrations are not likely to fall any time soon without policies most governments are currently not willing to implement.

Sorry for the confusion. This thread had degenerated in yet another silly argument between me and Mike and I forgot others were reading.
There's unfortunately lots of confusion on this topic, some of which is deliberately engineered and some of which results from honest communication failures.
One thing you should know is that charts are generally not trivial to interpret and that confusers love showing you genuine as well as doctored charts with a message along the lines of "we report, you decide".
They also love to take other people's charts out of context and argue with them (ever heard of the "hockey stick"?). Best ignore the pictures.

The steepness of the curve represents the rate of increase of emissions.
You don't seem to trust charts - perhaps you don't know how to interpret and represent data.
You sound as if you know what you're talking about but what you actually say gives the game away.

Merry Christmas.

For those who don't remember or who didn't pay attention, that was the one who brought us propaganda funded by the fossil fuel industry.

Propaganda/data from here

Who funds it? - No idea. Probably the US government.

What is your field of expertise HFat? I doubt it's maths or engineering, if it were you'd be able to come up with an argument rather than reeling off stuff you've read on Wiki.

More distraction and ad homs.
For the record, Mike linked to a page from the US government. Mike doesn't do propaganda funded by the fossil fuels industry. What you linked to was discussed earlier.
I'm done replying to you.

Actually I think that was what you were talking about (unless I'm missing something?). You and Mike were talking about the rate of increase in C02 (either from fossil fuel emissions or in the total atmospheric C02 concentration). Mike said regardless of which, both were increasing at a faster rate than ever. The chart he posted was fossil fuel emissions, which clearly shows an accelerating rate. You said the steepness of the curve is not the same as 'rate of growth'. It seems to me that the rate of growth (in emissions) is what the chart shows. This may not correlate into total atmospheric concentration, but the emissions rate seems to be growing.

Is the disagreement over whether the rate of growth in C02 emissions is increasing?



No problem. I'm just trying to understand, and to follow the discussion.

There's no disagreement about the data.
But there are three different rates: the rate of emissions, the absolute rate at which emissions are increasing and the rate of growth of emissions.

Maybe you'd understand if you compared emissions to GDP. I don't particularly care for GDP but it's something you've probably heard discussed extensively.
The world's real GDP is higher than ever, just like emissions are higher than ever. That's the first rate and the height of the curve in Mike's chart.
The world's real GDP also grew faster in absolute terms than any previous year in 2010, like emissions. That's the steepness in Mike's graph. But, as you know, people nevertheless talk about an economic crisis...
That's because the rate of growth, what you usually want to look at, is not the second but the third rate which isn't directly apparent in the chart.
In 1970, the world's real GDP grew at over 8% (third rate). In 2010, it grew at about half that rate and only because it was rebounding from a bad year. From 2008 to 2010, the yearly rate was less than 2%, lower than any three-year period since the Soviet Union collapsed. That's why people talk about a crisis.
Similarly, emissions growth (third rate) is at best half as strong as it was before the Arab oil embargo. Since then, people have learned to make a more efficient use of fossil fuels.
If emissions are to be reduced, people need to push efficency further, especially in places like China which would need to move to higher efficencies much faster than rich countries have done historically. It would actually trickier (see Jevon's paradox) but that's the gist of it.

As I originally stated, the rate of growth (the third rate) is what people look at when they talk about emissions reduction (you can tell because they use percentages while the second rate would be expressed in weight) and also what tells you how close a peak could be.
It's OK to use absoute growth (the second rate) when comparing a year to the next but, if you look farther in history, it exagerates current changes relative to past changes, just like absolute GDP growth hides how poor economic growth is these days compared to the post-WWII era.

When it comes to looking at charts, remember this: if you've got a value with a fixed rate of growth, the curve is going to get steeper with time and ultimately almost vertical.

Thanks, ok, I think I understand now. The amount of total C02 emissions has been steadily rising, but the rate (speed) at which the emissions have risen has varied over historical time. More rapid increases have occured before, eg. the decade prior to the Arab Embargo (approx. 1963-1973?) compared with now.

If Mike's chart were more fine grained, would it be able to indicate the 'rate of emission growth' by the steepness of curve? Or is another value on the chart needed?

Growth rate can be roughly inferred by looking at the chart. It's not the slope of the curve alone, though, that indicates growth rate; you need to look at the slope of the curve at a given point relative to the height at that point.

Or in other words, you would want to look at year-over-year growth, expressed as a percentage of the previous year.

Looking at the chart, for example:

Total emissions in 1975: 4.5 billion tons
Total emissions in 1980: 5.3 billion tons
Percent growth from 1975 to 1980: (5.3 - 4.5) / 4.5 * 100 = 17.7%
Average yearly growth rate from 1975 to 1980: 17.7% / 5 years = 3.6% per year

Total emissions in 2005: 8 billion tons
Total emissions (predicted) in 2010: 9 billion tons
Percent growth from 2005 to 2010: (9 - 8 ) / 8 * 100 = 12.5%
Average yearly growth rate from 2005 to 2010: 12.5% / 5 years = 2.5% per year


So to HFat's point, even though CO2 emissions are growing faster than ever before in absolute terms, the growth rate is considerably less now than it was 30 years ago.

If click on Mike's link, you can download the dataset and build your own chart showing growth rates or whatever else you want to show. Or you can simply use the dataset to make such calculations quicker and more reliably than by eyeballing the chart. You can do this with a simple spreadsheet like LibreOffice's Calc.
I thought this was obvious but I realized over the years that some people do not realize it's easy to make your own graphs. Maybe that's less common now.

edit: also, note how emissions from coal have not been rising steadily. There's been a long pause and growth has resumed relatively recently. That's particularily significant because coal is easier to replace than oil and gas which are also running out faster anyway.

You had me up until here:



If C02 emissions are growing faster than ever before, then 'faster' must refer to rate. What else could 'rate' mean? But then you say the growth 'rate' is considerably less (than 30 years ago).

From 1975 to 1980 the rate of growth was 3.6%
From 2005 to 2010 the rate of growth was 2.5%

Therefore C02 emissions are not growing faster than ever, since there was a time when they did grow faster.

As I said above, there are different rates with different units. Except for the annualization of the growth rate, gregrah was correct.
From 2005 to 2010, 2.4% or 0.2 billion tons.
From 1975 to 1980, 3.3% or 0.16 billon tons.
(I'm trusting gregrah's reading of the chart here because the exact numbers are irrelevant for our purpose.)

The rate with percentages is the one people usually look at but since you wanted an explanation for the slope of the curve, we had to explain the other rate it represents. And now we have several rates, which causes some confusion.
And all this because of a simple chart... they're best used as illustrations, not arguments. When people say something like "look at this chart", too much remains implicit. If Mike had written something like "from 2005 to 2010 emissions increased by 1 billon tons per year" instead of posting a picture, we wouldn't have to clear this up. He might even have realized on his own he should have looked at percentages.

The facts and figures are important to take on board, but the most important thing is the reality in the environment.

Here in central New England, the ground has frozen on the surface 3 times, but has now thawed again. It is 5 days after the winter solstice and only 5 days until the new year. This is pretty freaky -- one can contemplate a winter very soon when the ground will not freeze more than a inch of the surface of the ground. Building codes here require foundation footings to be at least 4 FEET below the surface to avoid the ground freezing under them...

This affects many things. Trees will not dormant which will affect their growth and the fruit they may bear. We are now seeing birds like the Carolina wren for the first time. Species are going extinct at an alarming rate -- we are in the 6th great extinction. We are seeing this:

http://news.yahoo.com/blogs/sideshow/giant-plumes-methane-bubbling-surface-arctic-ocean-163804179.html

And this: http://hereandnow.wbur.org/2011/12/20/climate-change-himalayas

We are having record warmth, record floods, record droughts, fires, dropping water tables, fishing collapses, crop losses, rising ocean levels, spreading of tropical diseases, population migrations, etc. etc.

Here in Calgary, Canada on the prairies, it is above 5 C and has been around this temp (give or take a few degrees) for a week or so. It is not due to a seasonal chinook. There was no white Christmas this year, not completely unusual given the last 10 years, but compared to when I was a child when there were always high snow drifts and cold temps during Christmas holidays (I still have childhood photos showing this), things have changed remarkably.

Greetings,

This video sums up our world situation as well as anything I have come across -- please watch:

http://www.youtube.com/watch?v=Sv2MHEDlXlU