All this month the BBC World Service is travelling along the rivers of Bangladesh as part of a major project to track and debate climate change.
Ben Sutherland is among those on board the vessel, the MV Aboshar.
1 November - BLEAK FUTURE
Along the journey so far we have met a number of people who are among the most vulnerable possible on the planet - but none more so than the residents of Bou Doba char.
A "char" is the name given to an island that forms from collected silt and sediment washed down the river - often, in fact, the result of the erosion which is causing problems for people further upstream.
Effectively, millimetre by millimetre, new terrain literally rises out of the river.
Bou Doba char is populated by a few very large, and young, families
Although initially it is uninhabitable, after around four years the quality of the soil improves to the extent that crops can be grown on it.
At this point, there is a rush for the new land. Bou Doba char is covered in banana trees from when people - mostly residents of already existing chars - literally uprooted the ones growing where they lived, took them across and replanted them to claim a space.
They then returned for the scraps of corrugated iron they used to build their shelters.
One man, Ahatar Padhr, who was one of the first to move to Bou Doba char, said that he arrived when the land was only visible at low tide, meaning that he was flooded up to thigh height every day.
But once settled, life is incredibly hard. The people live a remote, agrarian existence. One particularly vivid illustration was the sight of a young boy driving a herd of emaciated cattle down towards a stream.
In fact, there are very few adults here. The vast majority of the population are children; the first two families we met had eight each.
These people grow what crops and livestock they can, for sale at markets that may be a day or more away. There is obviously no infrastructure at all - this is raw land - so there are no schools, shops or roads.
And there is little point in building any either, because the chars do not last long.
Bou Doba char only became habitable around five years ago, but is itself already eroding fast; those that have been able to find somewhere else to go to have already left.
Only a residual 2,000 or so hang on, but they face a very bleak future.
2 November - PREPARING FOR CHANGE
The next day we headed to Bhola, a large, flat island in southern Bangladesh.
It was here that we were to record the first of the four BBC Bangladesh Sanglap river journey shows - hour-long debates in front of a live audience on the riverbank, in a similar format to the famous Question Time programme in the UK.
The show was being recorded the day after, but there was much work for the local crews to do in setting up.
For us on the MV Aboshar, this meant keeping out of the way at the back of the boat, where a large set was to be constructed which would feature in the background during the shooting.
Around midday the set arrived - unexpectedly pre-built. Effectively, it was one very large wooden block.
While it was handy that there was less work to do on board the boat, it meant a frenzied and back-breaking time for those on the end of the ropes and poles who had to haul it 30 feet (10 metres) off a small wooden rowing boat and onto the MV Aboshar..
Meanwhile, also joining us on board - but with considerably less difficulty - was Dr Saleemul Huq, one of the key authors of the latest report by the Intergovernmental Panel on Climate Change.
Originally from Bangladesh himself, Dr Huq explained that for the first time the IPCC had been able to base its findings not only on future predictions, but on data from recent years and in particular the increasing frequency of extreme weather in places around the world.
In Bangladesh, extreme flooding - defined as that which covers 30-40% of the country - should only occur once every 20 years. But recently it has been happening once every five.
"That is a very strong message that something has changed in the last 10 years," Dr Huq told us.
"The only explanation that is consistent across all these events - droughts, floods, cyclones, ice melt, temperatures across the spectrum - is that we are already in a man-made climate-changed world."
What this means for the people here is that they will have to prepare for what is coming. Already, some of these things are being done - and we will see and explain much more of this later in our journey.
3 November - HOTTER NIGHTS
However, when we visited the town of Bhola the next day, we found that not everyone is so concerned.
As one shopkeeper pointed out, flooding has been a way of life in this part of the world for centuries.
"The climate is always changing," he said.
"Flooding has always been going on; it is inevitable everywhere, because this is the biggest delta district in the country. When the levels of the Meghna rise, flooding is imminent - it is simple."
And as Dr Huq said, no one specific weather event can categorically be defined as a direct result of climate change. All that can be said is that extreme weather is the type of thing that can be expected.
But other residents told us they had indeed noticed that something is different now.
They include 70-year-old Abdul Hassan, a one-eyed tobacco seller in Bhola's impossibly crowded bazaar.
"The days are very much hotter now, and the nights much colder," he told us.
"It has been this way for four or five years. I have already suffered from these changes; floods three months ago broke through into my home.
"Rich countries like America and India have not banned carbon dioxide. When they do it will be sorted out."
4 November - TAKING THE TEMPERATURE
On Sunday morning, the boat chugged forward out of Bhola - the previous day's Sanglap recording having gone off without a hitch - and took a detour towards the city of Barisal to pick up supplies and a new supply of journalists.
We have now been joined by colleagues from the Chinese, Latin American, Azeri, Brazilian, Hindi, Mandarin, Indonesian and Russian services, as well as BBC World television.
Our "newsroom-on-the-water" is powered by solar energy
The main cabin, in which we have been spending our time when not on shore, now looks like a newsroom on the water.
The reason for the sudden influx is that this is a very important week for the World Service, as the Taking The Temperature season starts.
Starting with the announcement of the results of a global survey into people's opinions on climate change, Taking The Temperature will also be debating the prospects for action, the potential global impact and the biggest carbon dioxide emitting countries - whose actions, scientists say, are affecting people here, around these rivers.