'This place is just...crazy!!!!' It's a kind of ritual you have to go through with every new person you meet in the cavernous Bella Centre. You have to share your bewilderment at being in the eye of the storm that is the Copenhagen climate talks, before you can get down to business.

I've never been to one of these huge international summits before - and this one probably dwarfs most others. It's overwhelming. There are thousands of delegates swarming around: governments, NGOs and corporate lobbyists; young people, indigenous people, media people; several people, inevitably, dressed as polar bears. Everyone's here with their own agenda, trying to get the outcome they want. How to spend your time is a serious dilemma.

As I wander round, the background buzz of plots being hatched, deals being struck and steam being let off periodically erupts into some kind of demonstration. Before I'd even made it to the entrance I was accosted by a smiley mob telling me to cut meat out of my diet to save the planet. Grabbing lunch I suddenly found myself surrounded by a flashmob of young people 'freezing' for 350 seconds to call on developed countries to 'unfreeze' negotiations and support small island states through slashing their emissions.

This afternoon I encountered a noisy demo of wastepickers calling for more recycling, shortly followed by the announcement of 'Fossil of the Day', an award for the country doing the most to block an ambitious, fair and binding deal. Canada came an unprecedented second AND first today - as they should for their shameless attempts to block a strong deal in order to keep sucking out those tar sands.

Meanwhile, the first big street protests kicked off. Hundreds of demonstrators attempted to disrupt corporate events in the town centre, and just as many police were disappointingly effective in stopping them. This resulted in the first few 'pre-emptive' arrests of the summit, following the passage of a special law just for summit protesters that allows the cops to nick them before they've done anything. The experience doesn't sound too pleasant.

In the midst of all this, there are, of course, some negotiations going on. You'd need a PhD to fully understand the negotiation process, but essentially what we're seeing is a familiar tug of war. On one hand, industrialised nations are digging their heels in and hanging on for dear life to inadequate emissions cuts that won't keep global warming under 2 degrees, all delivered thorough disasterous market-based mechanisms like carbon trading. On the others, developing countries are heaving with all their might to drag them in the right direction, demanding deep emissions cuts to deliver less than 1.5 degrees warming, and a hefty finance package to help them adapt. Progress has been measly. Things are already getting fractious and, when the Heads of State swoop in next week, may well descend into all-out war.

The brightest spot of my day was interviewing Angelica Navarro, Bolivia's chief negotiator. A wonderfully inspiring woman, she is doing what she can to fight for climate justice and the preservation of Mother Earth, against extraordinary odds. She gave me hope that another world still just might be possible. But she said countries like Bolivia need all the support they can get from rich-world citizens.

Outside the Bella Centre global social movements are mustering, and we're going to give it our best shot. Today is a Global Day of Action. I'm going to be marching through the streets of Copenhagen with tens of thousands of people, in the 'System Change not Climate Change' bloc. It could well be the biggest climate demonstration the world has ever seen.

Will it have any impact inside the negotiations? I'll keep you posted...