With the global economy still in the doldrums, this year's World Environment Day on 5 June is trumpeting the merits of the Green Economy as an alternative way of creating jobs and growth - without trashing the planet.

It also takes place 15 days before the snappily-titled Rio+20 United Nations Conference on Sustainable Development, which kicks off in Brazil's most famous party town.

These global jamborees attract thousands of besuited delegates from across the world and often seem to generate a frenzy of discussion and chatter. They usually end with glowing speeches proclaiming positive progress with plenty of photo opportunities for smiling politicians to look thoroughly pleased with themselves. That, and usually a vastly complicated legal document outlining what everyone has managed to agree on so they can go home.

But although these summits can seem mystifyingly opaque and to do little more than create a lot of hot air, for many millions of our fellow human beings they actually have the potential to be the difference between life and death.

For people lucky enough to live in the UK, doing our bit for the environment can feel like nothing more than a good deed. But for those living in poverty in countries like Bangladesh, a country besieged by rising sea and flood water, assuaging the climate gods and making sure the rest of the world develops in a sustainable way is vital to keeping their heads above water.

Joyanta Adhikari, a 60-year-old Bangladeshi who runs a Christian Aid partner organisation raising awareness of the crisis faced by his country, told me coastal flooding was forcing people to live in the streets.

"We already have a large number of climate refugees who have been forced out of their homes and most of them have to live by the side of the road or in shanty towns," he said.

"Experts are forecasting that if the world doesn't change course we will see a rise in sea level of 1.5 metres by 2050.

"If that happens another 17 million people will be left homeless."

Rising sea levels have also led to other problems - salt water intrusion destroys paddy fields and agricultural land, which are the country's main food source.

The galling thing for the Bangladeshis is they weren't the ones responsible for, or the beneficiaries of, the carbon emissions which have heated the planet, melted global ice reserves and flooded their country. And what's worse, on their own they can't do anything to tackle the problem, which is why global get-togethers like the one in Rio in two weeks are so important.

Rio+20 seems very unlikely to produce any grand or significant outcomes by itself - but at Christian Aid we still think it's an important event which we want to influence.

Rio will set the direction for future work on, for instance, achieving access to sustainable energy for all, which would transform the lives of the 1.4 billion people who currently have no electricity. Furthermore, Rio is a major landmark in the discussions, debates and ultimately decisions about what should succeed the Millennium Development Goals after 2015. To us, it seems obvious that whatever comes next must push the world rapidly towards environmental sustainability, as well as social justice.

One final point about influence: unless a broad range of organisations from civil society do engage with Rio, there is a real danger that it will focus narrowly on low-carbon and 'green' technologies without tackling the bigger, thornier problems of global poverty and inequality. For the sake of more than a billion people who currently live in absolute poverty, we must make Rio embrace far more than technological fixes.

I think Joyanta summed it up pretty well when he said: "This world has enough for our need, but not our greed.

"We are all God's creation and we have to live responsibly to ensure God's world is not destroyed.

"We cannot solve the problem of climate change alone, we need the help of people in other countries."

To find out how you can support UK government to positively influence the talks, visit Rio Connection.

Follow Joe Ware on Twitter: www.twitter.com/wareisjoe