In this Friday, April 24, 2020 file photo, activists place thousands of protest placards in front of the Reichstag building, home of the german federal parliament, Bundestag, during a protest rally of the 'Fridays for Future' movement in Berlin, Germany. World leaders breathed an audible sigh of relief that the United States under President Joe Biden is rejoining the global effort to curb climate change, a cause that his predecessor had shunned. (AP Photo/Michael Sohn, File)

FILE - In this Feb. 4, 2020 file photo, Britain's Prime Minister Boris Johnson launches the upcoming UK-hosted COP26 UN Climate Summit in London, England. World leaders breathed an audible sigh of relief that the United States under President Joe Biden is rejoining the global effort to curb climate change, a cause that his predecessor had shunned. (Jeremy Selwyn/Pool via AP, File)

FILE - In this Sept. 19, 2019 file photo, an aircraft passes the rising sun during take off at the international airport in Frankfurt, Germany. World leaders breathed an audible sigh of relief that the United States under President Joe Biden is rejoining the global effort to curb climate change, a cause that his predecessor had shunned. (AP Photo/Michael Probst, File)

FILE - In this Friday, Nov. 30, 2018 file photo smoke rises from a factory as a truck loaded with cars crosses a bridge in Paris, France. World leaders breathed an audible sigh of relief that the United States under President Joe Biden is rejoining the global effort to curb climate change, a cause that his predecessor had shunned. (AP Photo/Michel Euler, File)

FILE - In this Jan. 11, 2021 file photo, French President Emmanuel Macron stands during the One Planet Summit, at The Elysee Palace, in Paris, France. World leaders breathed an audible sigh of relief that the United States under President Joe Biden is rejoining the global effort to curb climate change, a cause that his predecessor had shunned. (Ludovic Marin, Pool Photo via AP, File)

FILE - In this Dec. 8, 2019 file photo, a hundred activists hold portraits of President Emmanuel Macron to urge France to take action during the U.N. COP 25 climate talks in Madrid, during a gathering at Place du Trocadero facing the Eiffel Tower in Paris, France. World leaders breathed an audible sigh of relief that the United States under President Joe Biden is rejoining the global effort to curb climate change, a cause that his predecessor had shunned. (AP Photo/Francois Mori, File)

FILE - In this April 3, 2014 file photo giant machines dig for brown coal at the open-cast mining Garzweiler in front of a smoking power plant near the city of Grevenbroich in western Germany. World leaders breathed an audible sigh of relief that the United States under President Joe Biden is rejoining the global effort to curb climate change, a cause that his predecessor had shunned.  (AP Photo/Martin Meissner, File)

FILE - In this Saturday, June, 3, 2017 file photo, the coal-fired Plant Scherer, one of the nation's top carbon dioxide emitters, stands in the distance in Juliette, Ga.. World leaders breathed an audible sigh of relief that the United States under President Joe Biden is rejoining the global effort to curb climate change, a cause that his predecessor had shunned. British Prime Minister Boris Johnson and French President Emmanuel Macron were among those welcoming Biden’s decision on Wednesday, Jan. 20, 2021 to rejoin the the Paris climate accord. (AP Photo/Branden Camp, file)

FILE - In this Dec.12, 2015, file photo, an activist holds a poster during a demonstration near the Eiffel Tower, in Paris, during the COP21, the United Nations Climate Change Conference. For America's allies and rivals alike, the chaos unfolding during Donald Trump's final days as president is the logical result of four years of global instability brought on by the man who promised to change the way the world viewed the United States. Alliances that had held for generations have frayed to a breaking point — from leaving the Paris climate accord and Iran nuclear deal to quitting the World Health Organization amid a pandemic. (AP Photo/Thibault Camus, File)