Esther Williams is senior environment media officer for Tearfund.
I think it needs to be emphasised that we didn't come to the Cancun climate talks for the whole enchilada in terms of a deal. But we did and do expect some small bites of the burrito.
So when Connie Hedegaard reminded a packed press room that citizens all over the world mobilised in 2009 in the hope of seeing a fair climate deal, and that we can't leave Cancun empty handed, I think she managed to inject the momentum needed at the start of the second week.
That said, I do believe "cautious" and "optimism" are two words we should link together at this point.
The hope is that by Friday we come away with a "balanced package" - the latest buzz words bouncing off the walls in the corridors. Outside the Cancun bubble, this basically means we need to see an agreement that moves us closer towards a legally binding, fair climate deal in South Africa next year.
For this to happen, we need progress and secure building blocks in two key areas of the negotiations: the track focusing on the Kyoto Protocol, and the track on Long-term Cooperative Action (LCA).
This won't be plain sailing, but if all countries work together and come up with some tactical compromises, we could achieve an opening of the political space and a strengthening of trust between developed and developing countries. Which would be good news for the future.
There is definitely a sense of positivity in the air that goes beyond the "together again" camaraderie of thousands of civil society members who have galvanised to secure justice for poor people and the planet.
MONEY ON THE TABLE?
But what realistic bites of the burrito can we expect at Cancun? Coming into these talks, many NGOs and green groups believed this year's conference could set up a new climate fund with enough money committed to finance not just mitigation but climate change adaptation too.
In addition, we're lobbying for an agreement on where the money is coming from, along with clarity on how the fund will be governed so that fair representation is guaranteed for the poorest and most vulnerable countries.
In terms of carbon emissions, the current pledges under the non-binding Copenhagen Accord agreed at last year's disappointing summit must be - and here's another new climate term – "anchored" so they're not lost altogether. Even though they're inadequate, bringing them into a formal process at least means there's a chance of increasing them.
There is a real and tangible opportunity to deliver positive outcomes in Cancun. As environment ministers arrive, my hope is that countries will focus on what can be achieved rather than what they can get away with. To serve up a decent enchilada in South Africa next year, we need a few basic ingredients now.