Many celebrities use their platforms to raise awareness about causes that are close to their hearts; here are some of the stars that are making climate change and the environment their main priorities.

Leonardo DiCaprio

Leonardo DiCaprio set up his own foundation in 1998 which is "dedicated to the protection and wellbeing of all Earth's inhabitants." So far the foundation has funded over 200 projects around the world and awarded $100million in grants.

In 2014 he addressed the United Nations to speak about the issue, and after (finally) winning his Oscar in 2016 for his performance in The Revenant, DiCaprio took the chance to highlight climate change during his acceptance speech.

"Climate change is real, it is happening right now. It is the most urgent threat facing our entire species and we need to work collectively together and stop procrastinating," he said. According to statistics, Google searches for climate change soared the day after the awards show.

Most recently DiCaprio showed his support for activist Greta Thunberg, sharing photos of them on Instagram - where he regularly shares environmental news with her 37.7million followers - with the caption, "She and I have made a commitment to support one another, in hopes of securing a brighter future for our planet."

Jane Fonda

While Jane Fonda has been a climate change advocate for a long time, she has most recently been making headlines for her Fire Drill Fridays. The star has been arrested four times so far for leading rallies in the US about climate change and calling for greater resources and government support for the issue. Fonda plans to continue her Fire Drill Fridays into the New Year.

Not only is she putting herself at the front of the rally for change, Fonda has pledged that the red coat she has been wearing to the weekly marches will be the last piece of clothing she ever buys in a bid to be more sustainable.

"We cannot leave it to young people to fight this fight for their future by themselves," she said of her fight for climate change awareness.

Mark Ruffalo

Another celebrity with ties to an organisation aimed at protecting the environment and raising awareness about climate change is Mark Ruffalo.

A co-founder of The Solutions Project, which also counts his fellow Avengers star Don Cheadle in its ranks, Ruffalo is focused on supporting the aim to bring renewable energy to everyone.

The projects mission statement reads: "The Solutions Project accelerates the transition to 100% clean energy by championing a movement that is more inclusive, more collaborative, and more celebratory… Together, we can make renewable energy a reality for everyone."

Ruffalo hulks out when it comes to fracking and has been extremely vocal in his stance against the practice. He even called out Irish political leaders in a recent tweet to urge them to vote against the Shannon Liquefied Natural Gas terminal. In his tweet he hailed Ireland as a world leader with the country's ban on fracking.

Cate Blanchett

"I care about climate change because of our children. I want to safeguard their future," Cate Blanchett said.

Blanchett, along with her husband, playwright Andrew Upton, were instrumental in making the Sydney Theatre Company green by cutting waste, water use and carbon emissions at the company and through the production of their shows. From installing solar panels, rainwater systems and using recycled materials in their set design, Blanchett made a huge difference to the sustainability of the company while setting an example for others to follow.

Back in 2011, Blanchett appeared on an ad in Australia calling for the introduction of a carbon tax. The actress received some backlash in the wake of the ad being broadcast, but it didn't stop her from supporting the issue.

A star of the red carpet, Blanchett has also often shown her support for sustainable fashion.

Shailene Woodley

"What makes me want to do it is [that] I want to have kids. And I just can't justify bringing them into a world where I’m not fighting every single day to make direct change for future generations. So that’s my driver," Shailene Woodley has said of using her platform to raise awareness about climate change.

"We are nature ourselves, human beings, and we kind of easily lose sight of that."

Through her social media posts about the environment to the campaigns she aligns herself with, the Big Little Lies star is very vocal about her support for the environment, and in her personal life she has opened up about using chemical-free products and foraging for her own food.

As an Oceans Ambassador for Greepeace, and through the non-profit organisation, All It Takes, that she co-founded with her mother, the actress is taking her passion and enacting change.

Shawn Mendes

Shawn Mendes is an artist that is leading the charge in trying to make touring more sustainable to the environment.

Launching The Shawn Mendes Foundation, the singer is focusing on "youth-related causes" in areas like children's healthcare, sustainability, mental health, human rights, anti-bullying and education. Under the foundation's wide umbrella comes a partnership with Reverb, an environmental non-profit that assists artists in attempts to minimize their environmental footprints on tour.

"Our generation has the power to change the future of our planet, and to help carry that change forward for so many generations to follow," he said.

Mendes is also active in showing his support for climate change on his social media, reaching millions of followers.

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