NEW YORK (Reuters) - U.S. Republican Representative Darrell Issa of California has joined the Climate Solutions Caucus, a bipartisan group of lawmakers dedicated to fighting climate change, spokesmen for the group and Issa said on Wednesday. The group, founded a year ago by Florida lawmakers looking to slow the effects of global warming, like coastal flooding, now has 13 Republicans and 13 Democrats. It is committed to keeping an even number of members of both parties. The group hopes to become a counter-balance to President Donald Trump’s new administration, which includes several doubters of the science of climate change.  “This is a place where Democrats and Republicans are working together on problem that’s really difficult to solve,” said Daniel Richter, the caucus spokesman and legislative director for the Citizens Climate Lobby, a non-profit whose volunteers encourage members of Congress to join the caucus. Not all Republicans accept the idea that human activity is causing global temperatures to rise, a conclusion reached by an overwhelming majority of scientists. Others accuse Democrats of overly politicizing a scientific issue in an attempt to demonize their opponents. Trump, a Republican, has expressed skepticism about climate change, speculating during his campaign that global warming was “a hoax” and concern over it was “a money-making industry.” Richter said he hoped the caucus can one day be as powerful as the House Freedom Caucus, a group of Republicans whose votes en bloc have become a strong force for conservative activism, scuttling new legislation its members ideologically oppose. But he said, with Congress strongly weighted in favor of Republicans, the caucus will need at least a dozen more Republican members to become a significant force. 