The next big step in the fight to save the Arctic is happening right now.

Greenpeace US activists have suspended themselves from St. Johns Bridge in Portland, Oregon to block a Shell Oil vessel from leaving port for Alaskan waters. The climbers have enough supplies to last several days, and are prepared to stay in Shell's way as long as possible.

Follow here for breaking updates from the scene of this incredible display of people power, and don't forget to say #ShellNo yourself. Tune into the conversation on social media using #ShellNo, #PeopleVsShell, and #SaveTheArctic.

What's At Stake?

Why exactly have these activists chosen to put themselves in between Shell and the Arctic?

Shell is almost ready to drill in the Arctic, but a vessel containing a vital piece of drilling equipment – without which it is not permitted to drill – has a gaping hole in it. So it had to come down to Portland to get patched up. The climbers blocking its way are now what stands in between Shell and an Arctic oil catastrophe.

Shell isn't just threatening polar bears and walruses with its drilling plans. By tapping into a new source of oil – only accessible because of melting ice – it's threatening the entire world with worsening climate change. And here's the real irony: Shell wouldn't even be in Portland if it weren't for its own incompetence. Its icebreaker vessel, the Fennica, was damaged within weeks of leaving for the company's drilling site in Alaska's Chukchi Sea.

With billions of dollars and the US government in its pocket, Shell thinks it can get away with anything – even in the Arctic. But people around the world – including right here in Portland – are proving otherwise. Thanks to people power, the movement to save the Arctic is growing stronger every day, and we can win.

Shell would love for this fight to stay quiet, unseen and unheard by the millions of people worldwide who have spoken out against Arctic drilling. We can't let that happen.

Raise your voice and say #ShellNo. Tell President Obama to reject Arctic drilling today.

Ryan Schleeter is an online content producer for Greenpeace USA.