The unrestricted use of fossil fuels should be phased out
by 2100 if the world is to avoid dangerous climate change, a UN-backed expert panel
says.
The Intergovernmental Panel on Climate Change (IPCC) says
in a stark report that most of the world's electricity can - and must - be
produced from low-carbon sources by 2050. If not, the world faces "severe,
pervasive and irreversible" damage.
IPCC is the leading international body for the assessment
of climate change. It was established by the United Nations Environment
Programme (UNEP) and the World Meteorological Organization (WMO) in 1988 to
provide the world with clear scientific view on the current state of knowledge
in climate change and its potential environment and socio-economic impacts
The UN said inaction would cost "much more" than
taking the necessary action.
The IPCC's Synthesis Report was published on November 2, in
Copenhagen, after a week of intense debate between scientists and government officials.
It is intended to inform politicians engaged in attempts
to deliver a new global treaty on climate by the end of 2015.
The report says that reducing emissions is crucial if
global warming is to be limited to 2C - a target acknowledged in 2009 as the
threshold of dangerous climate change.
The report suggests renewables will have to grow from
their current 30% share to 80% of the power sector by 2050.
In the longer term, the report states that fossil fuel
power generation without carbon capture and storage (CCS) technology would need
to be "phased out almost entirely by 2100".
The Synthesis Report summarises three previous reports from
the IPCC, which outlined the causes, the impacts and the potential solutions to
climate change.
It re-states many familiar positions:
- Warming is "unequivocal" and the human influence on climate is clear
- The period from 1983 to 2012, it says, was likely the warmest 30 year period of the last 1,400 years
- Warming impacts are already being seen around the globe, in the acidification of the oceans, the melting of arctic ice and poorer crop yields in many parts
- Without concerted action on carbon, temperatures will increase over the coming decades and could be almost 5C above pre-industrial levels by the end of this century
UN Secretary-General Ban Ki-moon said. "There is no ambiguity
in their message. Leaders must act. Time is not on our side."
"There is a myth that climate action will cost heavily,"
said Mr Ban, "but inaction will cost much more."
The US Secretary of State, John Kerry, described the
report as "another canary in the coal mine".
"Those who choose to ignore or dispute the science
so clearly laid out in this report do so at great risk for all of us and for
our kids and grandkids," Mr Kerry said in a statement.
The Secretary of State for Energy and Climate Change Ed
Davey described the report as the "most comprehensive, thorough and robust
assessment of climate change ever produced".
"It sends a clear message that should be heard across
the world - we must act on climate change now. It's now up to the politicians –
we must safeguard the world for future generations by striking a new climate
deal in Paris next year," he said.
Prof Myles Allen from Oxford University, a member of the
IPCC core writing team, said: "If we can't develop carbon capture we will
have to stop using fossil fuels if we want to stop dangerous climate
change."
Sources: BBC News;
IPCC website