Climatology

People enjoy the sun and the fountains of the Trocadero gardens in Paris, Thursday July 25, 2019, when a new all-time high temperature of 42.6 degrees Celsius (108.7 F) hit the French capital. (AP Photo/Rafael Yaghobzadeh)

In this image taken on Thursday Aug.1, 2019 large rivers of melting water form on an ice sheet in western Greenland and drain into moulin holes that empty into the ocean from underneath the ice. The heat wave that smashed high temperature records in five European countries a week ago is now over Greenland, accelerating the melting of the island's ice sheet and causing massive ice loss in the Arctic. (Photo via Caspar Haarløv, Into the Ice via AP)

In this photo taken on Friday, July 26, 2019, Greta Thunberg stands next to Swedish parliament in Stockholm. Thunberg, the Swedish teenager whose social media-savvy brand of eco-activism has inspired tens of thousands of students in Europe to skip classes and protest for faster action against climate change, said Monday, July 29, 2019 that she plans to take her message to America the old-fashioned way: by boat. (AP Photo/David Keyton)

People cool down in the fountains as temperatures reached 30 degrees Celsius, at Toldbod Plads in Aalborg, Denmark, Wednesday July 24, 2019. (Henning Bagger/Ritzau Scanpix via AP)

Swedish climate activist Greta Thunberg, centre, arrives for a meeting in the French National Assembly, in Paris, France, Tuesdays, July 23, 2019. (AP Photo/Rafael Yaghobzadeh )

FILE - In this Dec. 4, 2018 file photo, people walk in Tree Library park in Milan, Italy. The city has ambitious plans to plant 3 million new trees by 2030_ a move that experts say could offer relief to the city's muggy and sometimes tropical weather. A study released on Thursday, July 4, 2019 says that the most effective way to fight global warming is to plant lots of trees - a trillion of them, maybe more. (AP Photo/Luca Bruno)

FILE - In this Dec. 4, 2018 file photo, people walk in Tree Library park in Milan, Italy. The city has ambitious plans to plant 3 million new trees by 2030_ a move that experts say could offer relief to the city's muggy and sometimes tropical weather. A study released on Thursday, July 4, 2019 says that the most effective way to fight global warming is to plant lots of trees - a trillion of them, maybe more. (AP Photo/Luca Bruno)

The German Arctic research vessel Polarstern is docked for maintenance in Bremerhaven, Germany, Wednesday, July 3, 2019. Scientists from 17 nations are preparing for a year-long mission to the central Arctic to study the impact that climate change is having on the frigid far north of the planet. Mission leader Markus Rex said that researchers plan to anchor the German icebreaker RV Polarstern to a large floe and set up camp on the ice as the sea freezes around them, conducting experiments throughout the Arctic winter. (AP Photos/Frank Jordans)

FILE - This May 24, 2006, file photo shows the village of Newtok, Alaska, where the eroding bank along the Ninglick River has long been a problem for the village, 480 miles west of Anchorage. Northern Alaska coastal communities and climate scientists say sea ice disappeared far earlier than normal this spring and it's affecting wildlife. The Anchorage Daily News reported in June 2019 that ice melted because of exceptionally warm ocean temperatures. (AP Photo/Al Grillo, File)

FILE - In this April 4, 2018 file photo, Kelly Knight Craft, U.S. Ambassador to Canada, speaks about NAFTA and Canada-US relations at an Empire Club meeting in Toronto. Craft is President Donald Trump's nominee to be the next U.S. envoy to the United Nations. (Chris Donovan/The Canadian Press via AP)