new york republican presidential contender donald trump say tuesday would renegotiate america role u.n. global climate accord spell potential doom agreement many view last chance turn tide global warm pull-out world second big carbon-emitting country would hobble deal reach paris last december nearly 200 nations first time two decades find common vision curb greenhouse gas emissions look seriously minimum renegotiate agreements minimum maximum may something else new york real estate mogul say interview reuters agreements one-sided agreements bad unite state trump say believe china world top emitter carbon dioxide gas many scientists believe contribute global climate change would adhere pledge paris deal big fan countries adhere china adhere china spew atmosphere say accord transform world fossil-fuel drive economy potent signal investors seek limit rise global temperatures less degrees celsius combine national pledge cut emissions provide fund develop nations mitigate damage effect sea level rise climate change obama administration pledge 26 28 percent domestic reduction greenhouse gas 2025 compare 2005 china promise would halt increase carbon emissions 2030. countries promise ratify deal year many u.s. republicans find fault deal overreact see uncertain threat former french foreign minister laurent fabius help broke deal say month u.s. election critical future climate change denier elect would threaten dramatically global action climate disruption say trump say believe global warm concept invent china hurt competitiveness u.s. business one energy policy advisers climate change skeptic u.s. congressman kevin cramer north dakota hillary clinton lead democratic contender white house advocate shift country 50 percent clean energy 2030. trump comment draw fire environmental advocate another example trump dangerous lack judgment real impact could us say gene karpinski president u.s.-based environmental group league conservation voters trump denunciation paris climate accord short sight would terribly costly america ability lead world go backwards important step towards clean energy economy benefit families billionaire environmental financier tom steyer say statement paris agreement article build mean protect countries accord event new government come want dismantle clause say nation want withdraw first wait four years u.s. chief climate envoy jonathan pershing say last week regardless outcome u.s. election countries likely bind pact exclusive skeptical trump say would renegotiate global climate deal