Latest emission figures show world on track for 4 degrees
Figures
released by the International Energy Agency (IEA) last week showed
that carbon emissions from energy production reached a record high
in 2010.
At 30.6 Gigatonnes, emissions were 5% higher than the previous
record year in 2008.
Dr. Fatih Birol, the chief economist of IEA called the latest
data "another wake-up call" while Lord Stern
warned that "the room for manoeuvre is narrow and the window of
opportunity is closing" for emissions cuts.
The IEA figures were particularly significant because emissions
had been expected to fall as a result of the economic downturn. As
a result of the recession, emissions fell
in the UK and globally
during 2009, leading some to suggest that the world had been given
"breathing space" to start a shift to low-carbon
infrastructure. The resurgence of carbon emissions makes it clear
that this hasn't happened.
Australian blog Skeptical
Science has now produced the following graph comparing current
global emissions with the IPCC 'emissions scenarios', which
speculate about future emissions and likely temperature changes
that may result.
Figure 1: US Energy Information Administration (EIA) global
human CO2 annual emissions from fossil fuels estimates vs. IPCC
SRES scenario projections. The IPCC Scenarios are based on
observed CO2 emissions until 2000, at which point the projections
take effect. For actual emissions, figures up to 2008 are taken
from the
EIA. 2009 emissions are 29Gt, 2010 emissions are 30.6Gt -
figures taken from the IEA.
The creators of the graph suggest that the best fit for
our behaviour in the real world is currently IPCC
Scenario A2, which describes a world where
there is:
* Delayed development of
renewable energy.
* Relatively slow change in
current birth and death rates.
* Relatively slow reduction of
inequality.
* Relatively slow improvement
in energy efficiency.
* No barriers to the use of
nuclear energy.
Scenario A2 gives a most likely global temperature rise of
around 3.5°C by 2100 above temperatures in 2000 - more than 4°C
above pre-industrial levels. See the second (red highlighted) grey
bar from the right in the graph below.
Figure 2: IPCC 2007 Working Group 1,
Figure SPM 5
If the prospect of a four-degree rise in temperatures by the end
of the century on current trends wasn't alarming enough, the IEA calculated
that 80 percent of projected 2020 emissions from the power sector
are already 'locked in' by infrastructure already being built or
has been given the go-ahead.
This means that emissions may well continue to accelerate - with
global emissions continuing to rise towards - or beyond - the
IPCC's most pessimistic A1FI or "fossil-fuel intensive"
projection.
Scenario planning gives a broad-brush picture of what future
temperature rise will be. Scientists needs more than a few years
data to draw conclusions about where we are going, so we don't know
exactly where we are going. But with the fall in emissions over the
last couple of years occurring as an accident of global economic
turmoil rather than because of infrastructure change, it's the
higher emissions scenarios that remain the most relevant for
mapping our future.
Ironically, relatively little research has been done on the
likely consequences of these higher-end scenarios - because
scientists assumed that the world would take action to reduce
emissions. Met Office scientist Richard Betts however
estimated in a paper published in later 2010 that the A1FI
scenario could lead to a temperature rise of 4 degrees in just
fifty years time (2060-70).
There is no doubt that the impacts of four degrees of
temperature rise would be incredibly serious for the environment
and for human society. One recent paper
concluded that:
"In such a 4°C world, the limits for
human adaptation are likely to be exceeded in many parts of the
world, while the limits for adaptation for natural systems would
largely be exceeded throughout the world. Hence, the ecosystem
services upon which human livelihoods depend would not be
preserved."
The disconnection of climate skeptics from the realities of the
debate were thrown into contrast during the debate around the IEA
publication. Dr Benny Peiser, director of the Global Warming Policy
Foundation argued
on Radio 4 that:
"… no-one really knows what the
trajectory will be within the next 100 years, whether the warming
trend will be pronounced, whether it will be moderate, whether it
will be smaller, no-one knows..."
Whilst may not know precisely what trajectory we are on, but it
is inaccurate - and irresponsible - to suggest that we don't have
ballpark figures for what will happen if global emissions aren't
curbed. We do - and the news isn't good.