Top environmental advocates on Wednesday urged the international community to increase and coordinate investments in research and development for renewable energy to make it cheaper than coal within 10 years. “A sensible approach to tackling climate change will not only pay for itself but provide economic benefits to the nations of the world,” they said in a petition, ahead of a key climate change conference in December. “We urge the leading nations of the world to commit to this positive, practical initiative by the Paris climate conference,” the petition said.–AFP