Obama to give major climate change speech Tuesday

US President Barack Obama will give a major speech on climate change Tuesday in which he is expected to propose executive action to cut carbon pollution. \"I\'ll lay out my vision for where I believe we need to go -- a national plan to reduce carbon pollution, prepare our country for the impacts of climate change, and lead global efforts to fight it,\" he said in a statement Saturday. Obama announced the speech on Twitter, calling global warming a \"serious challenge\" but one that is \"uniquely suited to America\'s strengths.\" \"We\'ll need scientists to design new fuels, and farmers to grow them. We\'ll need engineers to devise new sources of energy, and businesses to make and sell them. We\'ll need workers to build the foundation for a clean energy economy.\" \"And we\'ll need all of us, as citizens, to do our part to preserve God\'s creation for future generations - our forests and waterways, our croplands and snowcapped peaks,\" Obama said. \"There\'s no single step that can reverse the effects of climate change. But when it comes to the world we leave our children, we owe it to them to do what we can.\" Obama\'s past attempts at passing legislation on climate change have been blocked by Republicans in Congress, meaning he will likely take executive action that does not require legislative approval. US media said Obama was expected to announce tighter regulations on new and existing power plants -- particularly those fired by coal -- as well as tougher energy standards for consumer appliances. The administration was also expected to make more federal land available for solar and wind projects in a further boost to renewable energy, according to the Politico news website. Obama had hoped to pass \"cap and trade\" legislation during his first term to slash carbon emissions but the proposal was defeated in Congress. The president\'s Republican rivals have long slammed such efforts as wasteful government overreach, warning that tougher regulations will drive up the cost of energy and further hobble an already weak economy. Earlier this month, Obama and Chinese President Xi Jinping vowed joint action on climate change -- specifically the reduction of hydrofluorocarbons or \"super greenhouse gases\" -- after their first-ever summit in California. And last week, in a speech in Berlin, Obama said the United States \"will do more\" to tackle the threat of climate change and that the world must act before it is too late. \"Peace with justice means refusing to condemn our children to a harsher, less hospitable planet,\" he said on a blistering hot day at Brandenburg Gate. He said Germany, which is fast building up solar, wind and other renewable energies, and Europe, had led in efforts to battle a warming planet, melting ice caps and rising seas. He said the United States had also doubled renewable energies, boosted fuel efficiency in cars and brought down carbon emissions, but added: \"We know we have to do more and we will do more.\"