TORONTO -- Climate change activists Extinction Rebellion shut bridges across Canada and around the world this week, in a series of actions aimed raising awareness of a global “climate emergency.”

Here's a look at the group and what they hope to accomplish.

WHO ARE EXTINCTION REBELLION?

The environmental campaigners, known as XR, claim chapters in approximately 50 countries.

According to XR's website, the loose-knit, socio-political group launched on Oct. 31, 2018 and uses sit-ins, mass protests and non-violent, civil disobedience to draw attention to their aim of achieving net zero carbon emissions by 2025.

The group was spearheaded by U.K. environmental activists Roger Hallam and Gail Bradbrook.

On Wednesday, the group’s co-lead of outreach and communities joined CTV’s Your Morning to explain its actions.

“We took the bridges because symbolically the bridge to our future is now broken, we can’t get across, the road is blocked,” Irene Alatzakis said.

“Disruption is a method that civil disobedience uses to call attention to the matter. We don’t want to do it, we’re really sorry, but if you think about what climate change is doing around the world it has already disrupted lives.

“And it wakes people up, it disrupts their morning routine to say ‘Oh my God I have to think about this.’”

During protests, XR activists have been known to dress in white masks, face paint and red costumes. Demonstrators have splattered statutes, buildings and other public spaces with fake blood as part of the group's protests.

Last November, XR cited inspiration from other grassroots movements such as the Occupy protests, the U.S. Civil Rights movement, Gandhi's Satyagraha and suffragettes, according to The Guardian.

WHAT SPECIFICALLY ARE THEY PROTESTING

The group’s primary goal is to rally worldwide support for urgent action on climate change and to diminish greenhouse gases.

According to Extinction Rebellion’s website, the activists' core demands to international governments and other institutions are:

Tell the truth and declare a climate and ecological emergency.

Halt biodiversity loss and reduce greenhouse gas emissions to net zero by 2025 and be “led by the decisions of citizens’ assemblies on climate and ecological justice.”

“2020 is the big year to act,” Alatzakis said.

“Carbon emissions have to start falling down off the cliff. We’re at dangerously high levels, we have to have plans to draw it down and we expect our government to follow through on this.”

WHAT ARE THEY DOING?

On Monday, the group organized dozens of simultaneous protests around the world -- largely through sit-ins, flooding busy streets, and stopping traffic in major thoroughfares and bridges.

The protests in Canada were on some of the country’s busiest bridges including Angus L. Macdonald Bridge over Halifax Harbour, the Burrard Street bridge in Vancouver and the Prince Edward Viaduct in Toronto where protesters sprawled out on the roadway, according to The Canadian Press.

Meanwhile, demonstrators stopped traffic in European cities including Berlin, London, Paris and Amsterdam. In New York, activists smeared themselves -- and other emblems of Wall Street -- in fake blood and similarly laid in the street.

In some cities, activists occupied public spaces and even took to chaining themselves to vehicles and tent camps saying they’d be unwilling to move.

The group largely uses arrests as a tactic of civil disobedience with many activists wanting to get taken in by police to draw attention to their cause.

WHAT DOES EXTINCTION REBELLION’S SYMBOL MEAN?

The group and their supporters have taken to using a simple design of a circle with a stylized hourglass as their rallying symbol, with the logo appearing on posters, flags and banners.

Although the exact origins of the “extinction symbol” is something of a mystery, one U.K. report traced it back to an east London-based artist ESP or Goldfrog ESP who has a large Twitter and social media presence.

According to The Guardian and Ecohustler, the symbol is meant to represent the sixth mass extinction on earth with the circle representing the planet and the hourglass warning time is running out for countless species.

The symbol echoes the traditional peace sign with the ‘A’ inside of a circle symbol traditionally used by anarchists.

--- With files from CTVNews.ca writer Cillian O’Brien, The Canadian Press and The Associated Press