(Written on Friday)

The Rio conference is over. Tim and I are sitting in the tropical heat of our little flat overlooking the conference centre with the noise of the 20 diesel generators powering the vast halls coming through the door. Since yesterday’s rain, a new range of mountains has been revealed with improbably narrow needle-like peaks. We’re trying to figure out ‘what next’.

We’re not coming home to a radically changed situation. What was needed wasn’t achieved. But despite a lack of targets and timetables for action, we are coming home with some good political progress on Sustainable Development Goals, tackling unsustainable consumption and production, marine protection and how to measure progress beyond GDP. There is recommitment to many targets we had before. This may sound unambitious, but I always remember a fisheries campaigner telling me ‘Sacha, things can always get worse’.

So having dusted ourselves off, the challenge will now be for our Government and devolved administrations to translate the Rio+20 outcomes into national actions. We will need to make sure they are held to account.

We are also coming home to an increased realisation that we are going to have to think of extra ways to achieve our goals. Seeing real passion and leadership from the private sector – from companies such as Unilever and Aviva– has been great. We're already working with Tesco through our Together For Trees partnership to reduce the environmental impact of the products they sell (as well as funding our tropical rainforest work) and it's really encouraging to see that there are others in that sector who are keen to step up and do their bit.

One quote struck me, from the Chairman of Puma, Jochen Zeitz. When asked about Greenpeace’s campaign to Save the Arctic from drilling and destructive fishing: "As a private individual and businessman, this campaign is fundamental. I abhor that businesses want to use and destroy the environment and use the effects of such as an opportunity for more business and thus more destruction." I believe him, and its great to see companies such as his walking the walk.

The mountains that surround Rio are being reforested in a giant programme that has been quietly progressing for 20 years, bringing back the Atlantic rainforest. The whole city is dominated by nature, it's spectacular. I’ve been looking at broad beaches enviously since I got here. I cannot believe I never got a swim!

I have got to come and visit again (but only if it fits in my carbon budget!).