Earth Changes
There are no latrines for the 74,000 people who live in their section of Kibera, the biggest slum in Africa, which lies either side of the main railway line between Nairobi and Mombasa in the Kenyan highlands.
People there use what, with dark humour, are called "flying toilets". They defecate in a plastic bag and then throw it into the street or on to one of the vast dung heaps. Some just visit the heaps and relieve themselves directly. The heap next to Grace school is about 20 feet high and the size of a quarter of a football pitch.
The stench is unimaginable. When it rains, a noxious black liquid runs off the heap, and through the school, over the dirt floor of the classrooms. It seeps into the drinking water supply pipes, which run beneath the dump.
Oceans have already absorbed a third of the world's emissions of carbon dioxide, one of the heat-trapping gases blamed for global warming, leading to acidification that prevents vital sea life from forming properly.
The forecast called for more showers on Tuesday. Parts of the eastern Fraser Valley were hit by 300 millimetres of rain in the last few days that caused the Chilliwack River to overflow.
"The first massive movement of climate refugees has been that of people away from the Gulf Coast of the United States," said the Earth Policy Institute, which has warned for years that climate change demands action now.
Institute president Lester Brown said that about a quarter of a million people who fled the devastating impact of Hurricane Katrina a year ago must now be classed as "refugees".
"Interestingly, the country to suffer the most damage from a hurricane is also primarily responsible for global warming," he said.
Satellite measurements of the area of the Arctic covered by sea ice show that for every month this winter, the ice failed to return even to its long-term average rate of decline. It is the second consecutive winter that the sea ice has not managed to re-form enough to compensate for the unprecedented melting seen during the past few summers.
The report, published by the UK government, says there is only a small chance of greenhouse gas emissions being kept below "dangerous" levels.
It fears the Greenland ice sheet is likely to melt, leading sea levels to rise by seven metres over 1,000 years.
The poorest countries will be most vulnerable to these effects, it adds.