With the strongest warnings yet from the international scientific community on the threat of dangerous climate change just published, it's clearly time to match strengths of scientific warnings with determined action to reduce greenhouse gas emissions.
Strongest warning on climate change demands action
The latest report on the science of climate change from the
Intergovernmental Panel on Climate Change (IPCC) meeting in Paris,
concluded that continuing polluting business-as-usual practices is
likely to increase global average temperatures between 1.1°C and 6.4° C
above 1980-1999 levels by 2095, leading to more droughts, heatwaves,
floods and stronger hurricanes, rapid melting of ice-sheets and rapidly
rising sea levels.
Stephanie Tunmore, Greenpeace climate campaigner who was at
the meeting in Paris said, "The good news is our understanding of the
climate system and our impact on it has improved immensely. The bad
news is that the more we know, the more precarious the future looks.
There's a clear message to Governments here, and the window for action
is narrowing fast. If the last IPCC report was a wake up call, this one
is a screaming siren."
The main findings of the IPCC report are summarised below. Further reports will follow this year on at the probable
impacts of climate change, options for adapting to those impacts, and
possible routes to reducing emissions of greenhouse gases.
What's a few degrees?
While temperature increases of a few degrees might not sound so
dramatic it will have dramatic effects on our climate. That's why is
vital that action is taken now to reduce emissions and keep warming
below 2°C to prevent catastrophic climate impacts.
Fortunately, there is a blueprint for how to do this - the energy
(r)evolution. It shows how to cut global CO2 emissions in half by 2050, using
existing technology and still providing affordable energy and economic
growth. In short - a revolution in energy policy and an evolution in
how we use energy. Read more about the energy [r]evolution here.
We can have reliable renewable energy, and use energy more smartly to
achieve the cuts in carbon emissions required to prevent dangerous
climate change. Crucially, this can be done while phasing out damaging
and dangerous coal and nuclear energy.
As the science of climate change becomes ever more clear and alarming,
public concern is increasing rapidly. One of the few things not
matching the warning is the scale of real action from governments to
reduce emissions. If this stark warning goes ignored, future
generations will be enduring a warmer world of our own making and will not look
kindly on lack of action at the start of the 21st Century. Greenpeace activists having been taking action to send a clear message
to governments that the window for action is narrowing fast.
Human impact on climate has now been attributed with a 90
percent confidence, higher than in earlier assessments, and has been
found in all world regions.
An increase in the
theoretical climate ‘sensitivity’, i.e., how the climate will respond
to a doubling of greenhouse gases in the atmosphere compared to
pre-industrial levels. Previously, the best estimate for warming in
relation to GHG doubling was 2.5 degrees celsius, and now that has
increased to 3 degrees celsius.
Broad confirmation that the
range of warming expected by 2100 if emissions are not reduced is 1.1°C
and 6.4°C by 2095 over 1980-1999 levels.
The intensity of
tropical storms is likely to increase, a finding that was not possible
in the Third Assessment Report (TAR). Observed increases in intensity
are highly correlated with increased sea surface temperature.
The
Antarctic and Greenland ice sheets contributed a substantial amount
(around 15 percent) to the observed increase in sea level over the
1993-2003 period. However, the models say that the Antarctic ice sheet
should in fact be growing, due to increased precipitation, meaning that
as yet the models cannot explain the increase in the discharge of ice
especially from Antarctica, and don’t fully account for the rapid
melting and discharge of ice from Greenland. So, while it’s known that
sea-level rise will probably be greater, it is still difficult to
quantify precisely by how much.
A warming of 1.9 to 4.6°C above
pre-industrial levels, (well within the range expected for the 21st
century) would lead to the virtual elimination of the Greenland ice
sheet, if that warming is sustained for thousand years or more. That
would raise sea level by between 6 and 7 metres. The report also found
that future temperatures projected over Greenland are comparable to
those from a warm period 125, 000 years ago, when sea levels were 4-6
meters higher than they are today.