Negotiators grab head start on monumental climate challenge

* More and 150 heads of state and government to attend
Monday
* Sticking points include finance, cost of adaptation,
legality
* World needs 'trajectory' to a 2 degrees, or 1.5 degree cap

By Barbara Lewis and Bate Felix
PARIS, Nov 29 (Reuters) - Senior negotiators from almost 200
nations on Sunday began thrashing out a new global deal to curb
climate change as the president of China, the world's biggest
polluter, landed in Paris.
The United Nations conference begins at summit level on
Monday, when more than 150 heads of state and government -
including U.S. President Barack Obama and Chinese President Xi
Jinping - will attend talks at a sprawling complex north of the
French capital. Xi arrived on Sunday.
To signal determination to resolve the most intractable
issues, expert negotiators sat down on Sunday rather than after
Monday's high-level speeches, as originally planned.
French Foreign Minister Laurent Fabius said the aim was to
give the world the means to cap global warming at 2 degrees
Celsius (3.6 degrees Fahrenheit) above pre-industrial times or
even 1.5 degrees.
That would avoid the most devastating consequences of global
warming, such as rising sea-levels and desertification.
Referring to previous U.N. conferences that have dragged on
days beyond the official close, Fabius said relying on "a
last-night miracle" could risk failure. Progress must be made
every day.
"The process cannot be chaotic. We owe it to ourselves and
to the world to conclude the process in an orderly and
respectful manner," he said.
France, as well as hosting the Paris talks, formally takes
on leadership of the U.N. process for a year from Monday.
Governments hope the Paris summit will end on Dec. 11 in a
deal that will herald a shift from rising dependence on fossil
fuels since the Industrial Revolution to cleaner energies such
as wind or solar power. ID:nL8N13G09R
Hundreds of thousands of people on Sunday joined rallies
across the globe, telling leaders gathering for the summit there
is "No Planet B" in the fight against global warming.
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There is a tough task ahead. Weeks of preparatory talks this
year have struggled to whittle down a negotiating text, which is
still more than 50 pages long.
The most difficult issues include working out how to share
the burden of taking action between rich and poor nations, how
to finance the cost of adapting to global warming and the legal
format of any final text, as U.S. politicians are likely to
block a legally binding treaty.
"Some countries have concerns about all of the targets being
binding," Canadian Environment Minister Catherine McKenna told
reporters. "The idea is to have a binding agreement. There may
be elements that are not binding."
Canada, home to reserves of oil sands, one of the most
polluting forms of fossil fuel, withdrew from the 1997 Kyoto
Protocol, which any new Paris deal will replace.
It is re-engaging with U.N. talks following the election of
a Liberal government in October.
While big carbon burner China has been reluctant to submit
to any outside oversight of its carbon pledges made at a climate
summit in Copenhagen six years ago, it has promised to steer its
coal-powered economy to a greener path.
The Paris summit is being held in tight security after
attacks in Paris by Islamic State two weeks ago that killed 130
people.