By Gerard Wynn
LONDON Feb 23 Discriminating against tar
sands in the name of curbing carbon emissions makes sense, but
is also a distraction from a bigger question about how much
fossil fuel humankind can safely burn.
A calculation of the carbon dioxide emissions embedded in
global crude oil reserves shows that burning these would pump
out more CO2 than many scientists and world leaders have deemed
safe to the climate, after including additional emissions from
deforestation and burning coal and gas.
Simply maintaining present levels of crude oil consumption
over the next several decades would have the same effect,
implying a present carbon over-spend.
But many environmentalists have demonised a particular type
of crude oil from tar sands in Canada and Venezuela, which
involves high energy costs to pump oil from a thick, sandy
Burning gasoline derived from tar sands emits
10-25 percent more CO2 than conventional crude, but focusing on
tar sands neglects the other 91 percent of world crude reserves,
according to BP energy statistics, not to mention all other
A panel of European Union experts votes on Thursday on
whether to support a carbon label on gasoline refined from tar
sand crude oil, mirroring similar efforts by Californian
legislators under the U.S. state's low carbon fuel standard.
If approved, the EU label would make refiners think twice
about using tar sands crude, given that they already face
targets to cut CO2 emissions embedded in their fuel products.
A label is clearly a good idea, improving transparency over
the environmental implications of our energy choices.
But a more important, and politically more difficult, step
is to address coherently all the fossil fuels which the world's
economy depends on - which implies either preparing for more sea
level rise, erratic rains and heatwaves, or writing down the
assets of the world's biggest energy companies.
A useful framing discussion for the environmental impact of
fossil fuels is a letter published in the journal Nature three
The authors calculated that humankind could safely emit a
cumulative 1,440 billion tonnes of CO2 from 2000-2050 to have a
50 percent chance of world surface temperatures rising this
century by no more than 2 degrees Celsius, compared with
The 2 degrees threshold is a target derived more politically
than scientifically: governments have formally referred to it as
a safety limit at successive U.N. climate summits.
Some experts say that 2 degrees warming or more will lead to
the eventual collapse of the Greenland icesheet over centuries,
raising sea levels by 7 metres. Observations support more
dangerous heatwaves, volatile rainfall and sea level rise with
higher, global average temperatures.
It is widely acknowledged that the target is barely
achievable, and that at present the world is on track for more
than 3 degrees average surface warming by the end of the
In the last decade, cumulative (and still rising) CO2
emissions from burning fossil fuels and net land use change
including deforestation were about 337 billion tonnes, according
to BP and Global Carbon Project estimates.
That leaves 1,100 billion tonnes CO2 of the estimated
available budget left over the next four decades .
In other words, annual emissions at 2010 rates (36.5 billion
tonnes CO2 from land use change and fossil fuels) would consume
the remaining budget by 2040, a decade early.
Viewing the role of crude oil, consumption in 2010 was 87
million barrels per day, according to BP energy statistics.
That's equivalent to nearly 14 billion tonnes of CO2
emissions annually (calculated using a U.S. Environmental
Protection Agency conversion of 0.43 tonnes of CO2 emissions for
an average barrel of crude, accounting for emissions only from
burning, not producing, the oil).
If maintained through 2050 (actually predicted to rise in
the medium-term), such road fuel emissions would consume half
the calculated available CO2 budget.
That would require a cut in present annual CO2 pollution
from burning coal and gas (by about a third from 20 billion
tonnes in 2010), implying that some power plants would have to
be closed and burgeoning shale gas discoveries left unexploited.
A similar view is obtained by calculating the CO2 emissions
from simply burning all of the (conservatively) estimated proven
crude oil reserves, including tar sands, at 1,526 billion
The conclusion is that the European Commission and
Californian efforts are very worthwhile, taking a first step to
measuring and so limiting CO2 emissions from road fuel.
But a franker discussion about plans for all crude oil and
other fossil fuels is needed, given that the balance sheets of
the world economy and of energy companies presently assume the
environmental cost of burning these at almost zero, even in
Europe which has a carbon price, but at near all-time lows.
If EU member state experts approved the tar sands measure by
a majority on Thursday, and it were subsequently approved by the
European Parliament (as expected), the label would be adopted as
an amendment of an existing law, the Fuel Quality Directive.
A stalemate is more likely where it is neither approved nor
voted down, meaning a compromise would be voted on by EU
environment ministers within three months, again before scrutiny
A compromise may be around the level of extra CO2 emissions
attributed to gasoline from tar sand crude: the oil lobby
estimates this at about 11 percent more than average crude, some
academics at 15-20 percent more, and the European Commission at