

To say that this was a big year for the environmental movement is an understatement. From the Paris climate agreement to the indelible progress of renewable energy, 2015 was a landmark year.
And people didn’t hesitate to talk about it. Here are the 20 most popular hashtags on Twitter inspired by environmental progress made in 2015:
Climate change is not a political issue. It’s a people and a planet issue. #ActOnClimate pic.twitter.com/z7yGgERVVn
— Climate Reality (@ClimateReality) December 28, 2015
Activists ramped up the pressure on world leaders to reach a strong, global agreement on climate change at the UN COP21 Paris climate talks, calling it “our last, best chance” to do so. Climate change received far more attention from mainstream media outlets this year, and according to recent polling, more Americans than ever accept the science on global warming.
And part of that heightened awareness is thanks to the efforts of Pope Francis, who repeatedly spoke out about the need to take immediate action on climate change in 2015.
I can't even. #BlackFridayIn3Words
— Melissa Knowles (@Knowlesitall) November 23, 2015
More and more Americans became disenchanted with Black Friday, and they took to Twitter to express themselves in often very humorous ways.
3. #OptOutside
"My soul went Black Friday shopping. First on the list? Adventure." -Instagram's _gentry__ #OptOutside pic.twitter.com/5yNC03G22b
— REI (@REI) November 28, 2015
REI made waves when it announced that it would be closing all of its 143 retail locations, headquarters and two distribution centers on both Thanksgiving Day and Black Friday. All 12,000 full- and part-time employees received paid time off as the company encouraged them and everyone else to go outside instead.
This U.S. town plans to #Go100percent #renewables #OffGrid https://t.co/F20s2tJVPA via @ecowatch pic.twitter.com/CFQ5MoArbZ
— Climate Council (@climatecouncil) December 21, 2015
Uruguay; Burlington, Vermont; Aspen, Colorado; and Kodiak Island, Alaska were among the countries and cities that transitioned to run completely on renewables this year.
Costa Rica ran on renewables for almost all of 2015. From small towns like Nassau, New York to major cities such as San Diego, Vancouver and Las Vegas, pledges were made to go 100 percent renewable. Sweden vowed to as well. And Hawaii pledged to do so by 2045—the most ambitious standard set by a U.S. state thus far.
5. #Renewables
It's simple: If we're serious about reducing carbon emissions, #renewables are key to meeting our goals https://t.co/4JPwrCmOLR
— American Council on Renewable Energy (@ACORE) December 25, 2015
Renewables had another record-breaking year with solar and wind power growing like crazy—providing more than 5 percent of the nation’s electricity for the first time—and the country’s first offshore wind power project is finally under construction.