When you think of climate change images of scorched earth and ruined crops come to mind.

Ray Colgan assesses the social consequences of climate change on Nairobi slums 

The consequences for food supply are obvious, but there are social consequences too.

People are forced off land which can no longer support them, trying their luck in the city seems like a better option.

That’s what’s been happening in Kenya. The consequences can been seen in the filthy streets of Nairobi’s slums.

We visited Kibera, a maze of corrugated iron and mud shacks. The narrow streets are layers of earth, compacted rubbish, and well, let’s just say other unpleasant stuff mixed in too.

There is a preference in some quarters to use the term “informal settlement” rather than slum; the argument being that slum has negative connotations. The people who live in Kibera are aware of those negative connotations. They describe where they live as a slum. Frankly, what their area is called is the least of their problems.

Kibera officially is home to 170,000 people.

The real figure is probably closer to a million.

It is Africa’s biggest slum. Space is at a premium: homes and stalls run right along the side of the Nairobi to Mombassa railway line. It is a city within a city. Amid the mud and the dirt there are shops and even businesses making small furniture.

The influx of new arrivals has made for a very tense atmosphere. Fierce fighting broke out between various tribes in Kenya following the country’s last election.

Four Kenyan politicians are due to stand trial at the International Criminal Court for their role in encouraging the violence.

Across the country 1,200 people were killed. With so many people packed into so little space and in such awful conditions, it is easy to understand why Kibera saw some horrific incidents.

Locals tell us of gangs of hundreds of youths surrounding houses and looting; one woman describes seeing a child beaten to death on her doorstep. Whispers have already started ahead of next years election.

Another resident says gangs have been warning it will be three times worse.

There’s a lot I could say about the people we met there, how they are trying to solve their own problems and the children of Kibera who deserve a whole lot more. Probably best just to check out the video.

The complexities of what’s been happening in Kibera are as good an illustration as any of the problems those at the UN Summit on Sustainable Development are trying to deal with.

More and more people need more and more resources, creating social tensions and increasing strain on the environment.