The BBC is visiting eight areas of the world to find how people are preparing for climate change. The BBC has charted a special boat to travel the fragile Mekong delta in Vietnam, from where Tom Hannen reports.
The residents of Vietnam's capital, Ho Chi Minh City, are increasingly frequently finding themselves flooded out.
Locals say it is the most visible effect that climate change is having on the country. Tom Hannen found out how mangrove forests are being planted to help protect inland Vietnam from the rising flood tide.
With climate change anticipated to cause more frequent and severe flooding in the country, children in Vietnam are being taught to swim at a young age in order to prepare them.
Guidance: this video has no sound.
Students like Nguyen Pham Hong Van come from the area around the Mekong river delta and have seen the effects of climate change first hand.
In this video Nguyen and other students from Can Tho University appeal to the delegates of the for technology transfer and funds to offset the effects of climate change.
Changing global temperatures are having a noticeable effect on the rice harvest in Vietnam, according to the country's farmers.
Tom Hannen reports from the Mekong delta.
"Together The Green World" is the title of the brass sign, hung in the hotel bathroom. It urges me not to waste water or electricity during my stay in Ho Chi Minh City. This is a city hungry for energy.
Leaving the airport, I was greeted by an incredibly bright, high-definition TV screen, advertising mobile phones. The modern glow of LED lighting adorns everything - the inside of the taxis, cascades of bulbs suspended from trees, multi-leveled pagoda roofs.
The city is full of mopeds. The drivers' carefully colour coordinated helmets bob along through the seething traffic.
Smog and dust are real problems here, so most of the moped riders cover their mouths with handkerchiefs or masks. At garages they can be seen refueling - and socialising. Whole families on a single moped is not uncommon.
This means that the frequent flooding of the main roads can be a real problem here. As we left the city, we drove through foot-deep brackish water - high tides frequently cause main roads to flood.
We were visiting fisherman who have a new role - as guardians of freshly planted mangrove forests by the riverside.
The mangroves have been grown their as part of a governmental programme to try to lessen the impact of flood waters on the surrounding land.
The snaking roots of the mangrove twist and knot deeply into the river bed, helping sediment to build up, and slow down any flash flooding. They also help to improve the overall ecology of the water by storing heavy metals from the water.
Later, despite a local government presence, we were able to speak to some rice farmers who were frantically harvesting their crop at an incredible speed.
The cutting of the rice was all done by women - hacking through the paddy field with scythes by hand.
Vietnam is known as a key part of "The Rice Bowl of Asia" and is one of the largest exporters of rice in the region.
Once they had bundled the rice up into piles, a rusty petrol-driven contraption was fired up to remove the rice from the stalks, tossing the chaff high into the air.
The harvest takes place four times a year. In a way, this process was a great example of the demands the developing world is making of the richer nations at the Copenhagen Summit. The "embodied energy" - the amount of CO2 required to produce it - of this rice must be very low, in comparison to more agriculturally developed farming practices
An equivalent farm in the US would only employ a handful of people manning GPS-driven tractors around the fields. Much more productive possibly, but also much more reliant on fossil fuels.
For Vietnam, climate change is not a theory.
It is already affecting the lives and livelihoods of millions of people living in the Mekong delta.
The people there - 22% of Vietnam's population - have a simple choice: adapt, or leave the delta.
The delta produces food - rice, fruit, vegetables and fish - for millions of people. But sea levels are already rising, cyclones are becoming more common and more intense, and the summers are bringing drought.
Many already move to the cities in the wet season - although the main centre, Can Tho, will be under water itself in 20 years.
The government is resettling thousands to higher land, raising sea defences and replanting mangroves. Non-governmental organisations are helping farmers grow more saline-tolerant rice, and diversify into fruit farming.
But it is likely that millions will eventually have to move from the Delta. How will the government cope with such a mass human migration?