THE evidence for global warming is "unequivocal", and it is
"extremely likely" that human activity has been the dominant cause
of the phenomenon since the mid-20th century, a new UN report
The fifth assessment of the Intergovernmental Panel on Climate
Change (IPCC) is based on about 9000 peer-reviewed scientific
papers and 50,000 comments from expert reviewers.
Published on Friday, the summary of the report, Climate
Change 2013: the Physical Science Basis, states that "Warming
in the climate system is unequivocal and since 1950 many changes
have been observed throughout the climate system that are
unprecedented over decades to millennia.
"Each of the last three decades has been successively warmer at
the Earth's surface than any preceding decade since 1850."
It is "extremely likely that human influence has been the
dominant cause of the observed warming since the mid-20th century",
the report states. "Extremely likely" refers to a 95-100-per-cent
Dr Thomas Stocker, Professor of Climate and Environmental
Physics at the University of Berlin, who co-chairs the working
group that produced the report, said: "Continued emissions of
greenhouse gases will cause further warming and changes in all
components of the climate system. Limiting climate change will
require substantial and sustained reductions of greenhouse-gas
The group has predicted that the earth will warm by more than
1.5°C by the end of the 21st century, relative to 1850-1900,
possibly by more than 2°C. Sea levels are expected to rise at a
faster rate than that seen in the past 40 years, by between 26 and
81cm, as the ocean warms and glaciers reduce. In the Copenhagen
Accord in 2009, governments promised to prevent the rise of global
temperature by 2°C above pre-industrial levels.
Professor Stocker said: "Heatwaves are very likely to occur
more frequently and last longer. As the earth warms, we
expect to see currently wet regions receiving more rainfall, and
dry regions receiving less, although there will be exceptions."
He warned that the effects of climate change would persist "for
many centuries", even if emissions of carbon dioxide, were to
On Friday, the chairman of the Mission and Public Affairs
Council, Philip Fletcher, said that the report made it "clearer
than ever that climate change is happening, that we, the human
race, are largely or completely responsible for that, and that we
really ought to proceed on that basis, rather than just hoping that
it will all turn out to be wrong".
The Church of England is committed to reducing its carbon
footprint by 80 per cent by 2050, with an interim target of 42 per
cent by 2020. St Michael and All Angels', Withington, Gloucester,
is claimed to be the first zero-carbon church in the UK since the
PCC took measures that included installing a biomass boiler and
"There are things we do well and things we do badly but we have
been seeking to work at shriking our own footprint for some time,"
Mr Fletcher said. "We know that we should be doing more, and we
shall be thinking hard about the implications of that. We are
taking it seriously, and we know we are part of the problem."
On Friday, Christian Aid's senior climate change adviser, Dr
Alison Doig, said: "We need to support countries and communities
most at risk in preparing to cope with disaster, to lessen the
impacts of extreme weather events, and help communities recover
more rapidly when they do occur.
"As a developed, industrialised country, the UK has to lead the
way by ending our dependence on fossil fuels, and investing in
clean, renewable sources of energy, which we are fortunate enough
to be blessed with in the UK."
The advocacy director at Tearfund, Paul Cook, said: "This report
gives further scientific backing to what our partner organisations
around the world have been telling us: the climate is changing, and
not in a good way. Droughts, floods, and erratic weather are
ruining crops and damaging communities."
The IPCC was established by the UN and the World
Meteorological Organization in 1988 "to provide the world with a
clear scientific view on the current state of knowledge in climate
change and its potential environmental and socio-economic impacts".
It does not conduct research, but assesses the most recent relevant
material. Thousands of scientists from across the world contribute
to its work. Currently, 195 countries are members of the IPCC.
Governments endorse its reports, and it describes itself as
"policy-relevant and yet policy-neutral, never