Why we can't bank on recessions to keep global warming in check

[xchrom]

http://www.guardian.co.uk/environment/blog/2012/oct/08/recessions-global-warming-check?intcmp=122
Cars bought during times of economic growth could be responsible for carbon emissions not falling as fast as GDP during recessions. Illustration: Alamy



Greenhouse gas emissions rise when economies expand but don't fall as quickly when recession strikes, according to new research that emphasises the risks of relying on economic downturns to keep future emissions in check.

The most likely reason is that carbon-emitting vehicles and infrastructure created as the economy grows continue to be used in harder times, even as the economy contracts.

Based on a review of World Bank statistics of more than 150 nations from 1960 to 2008, the research – published in Nature Climate Change on Sunday – found that emissions of carbon dioxide rose by an average of 0.7% for every 1% growth in gross domestic product (GDP) per capita. But emissions fell just 0.43% for every 1% decline in GDP per capita.

[AverageJoe90]

1. Very true, and population reduction won't do a damn thing, either.

We need to focus on alternative fuels, carbon sequestering, and other technologies that will play a role in combatting global warming. We really don't have a choice if we want a shot at improving our global environment.

[GliderGuider]

2. That depends on how much population reduction you're talking about.

3 billion people can't drive as many cars as 7 billion can...

[AverageJoe90]

4. I'm afraid it probably won't.

Paul, the big problem is, is that although cars are a somewhat significant source of Co2 emissions they are by no means, the biggest culprit.
And unfortunately, none of the scenarios I've seen so far take into account what could happen if the crooks amongst the big energy companies decide to take full advantage of the situation by redoubling their efforts to drill in the Arctic, and other things. Sadly, this is a reality we could be facing in a less populated world.

[GliderGuider]

5. That's short term thinking.

Let Mother Nature fully into the equation and give her 50 to 100 years. You won't recognize the old homestead. Our efforts over the next 20 years will only make her final housecleaning that much more thorough.

I've concluded that we have no idea what realities we will be facing, in either a more or less populated world. We simply lay our beliefs on the table, bet our bodies and souls on the outcome and play the cards as they come up.

[AverageJoe90]

6. Depends on what you mean by final housecleaning.

As for what we could face? It's true that we may not know exactly. But science does give us a basic idea of what we could be facing in various climate scenarios by the end of this century(and sadly, I'm not convinced we'll be at or even below 2*C by 2100, even with drastic measures, barring, of course, some sort of miracle).

[GliderGuider]

7. What I mean by "final housecleaning"

Is a planet playing host to a few tens of millions of humans, and about half the species it currently sports, in 100 years. A planet that has seen a 6° C rise in average temperatures, with an increase of 15° C around the poles, a globe-girdling band of desert between the two Tropics and with acidic, anoxic oceans that support maybe 10% of the biomass they did 100 years ago.

I don't think we'll get to Canfield oceans in 100 years, but within 200 years even that is possible.

Peter Ward's book on oceanic catastrophe: Under A Green Sky is well worth a read.

And here's a glimpse of 6 degrees from three years ago:

http://www.independent.co.uk/environment/climate-change/world-on-course-for-catastrophic-6deg-rise-reveal-scientists-1822396.html

The world is now firmly on course for the worst-case scenario in terms of climate change, with average global temperatures rising by up to 6C by the end of the century, leading scientists said yesterday. Such a rise – which would be much higher nearer the poles – would have cataclysmic and irreversible consequences for the Earth, making large parts of the planet uninhabitable and threatening the basis of human civilisation.

We are headed for it, the scientists said, because the carbon dioxide emissions from industry, transport and deforestation which are responsible for warming the atmosphere have increased dramatically since 2002, in a way which no one anticipated, and are now running at treble the annual rate of the 1990s.

This means that the most extreme scenario envisaged in the last report from the UN Intergovernmental Panel on Climate Change, published in 2007, is now the one for which society is set, according to the 31 researchers from seven countries involved in the Global Carbon Project.

Although the 6C rise and its potential disastrous effects have been speculated upon before, this is the first time that scientists have said that society is now on a path to meet it.

Also covered by New Scientist:
http://www.newscientist.com/blogs/shortsharpscience/2009/11/world-on-track-to-rise-by-6-de.html

The GCP: http://www.globalcarbonproject.org/

Given that the climate effects we expected at 2° degrees are appearing already at 0.8°, this does not make me happy.

[pscot]

9. Current trend suggests a billion U.S citizens

in a hundred years. Some lifestyle adjustments may take place.

[GliderGuider]

3. Both the article and the study's author carefully ignore one looming possibility

That is the possibility of a recession sans finis. The possibility of a permanent, ongoing contraction of the global economy nicely eliminates the "growth phases" that this argument hinges on (or swings by, take your pick).

A permanent contraction would simply mirror the essentially continuous growth that the world economy has been experiencing since 1800 or so. Anyone who thinks that such growth represents some preordained state of natural affairs (whether desirable or not) hasn't been paying attention to the real world.

The "sustainable period" of modern civilization might be imagined as the period between AD 1 and AD 1800, when the growth in average per-capita GDP (in constant 1990 dollars) amounted to something between 0.04% and 0.06% per year. Between 1800 and 1900 per-capita GDP grew by an average of 0.7% per year - over ten times as fast as during the two previous millennia. Then between 1900 and 1950 the rate accelerated to around 1.3% per year and since 1950 has been running at 2% to 3% per annum. *

Such growth rates are obviously not sustainable, especially when they require similar supporting growth in the use of fossil fuels (as they have for the last 250 years, a trend which shows no sign of changing). This growth will eventually, inevitably reverse for one reason or another, or for a whole converging set of reasons. When that happens the resulting contraction - aka permanent global recession - will bring GHG emissions down with it.

Whether such an eventuality might correspond to a commensurate reduction in population, how such a reduction might be distributed across the regions and countries of the planet, and why, is left as a thought experiment for the reader.

* These numbers have been derived from the work of Angus Maddison (XLS)

[pscot]

10. Population decline would most definitely compromise

our economic arrangements.

[Kennah]

8. Not to worry, a depression can't be far off