Few places present as many challenges to travellers as the Amazon.
Follow my progress as I investigate how climate change and logging are affecting a region that has more than half the planet's remaining rainforests.
19 JULY: ROOT OF THE PROBLEM
In the fierce midday heat, a small boat slides over the black waters of the Rio Negro, draws up to our broadcasting position in the jungle and disgorges two improbably distinguished visitors to this remote corner of rainforest 1,000 miles up the Amazon.
We have arranged an interactive session to answer your questions and have invited the two visitors to lend a hand. We couldn't have more relevant people: the Bishop of Liverpool, the Right Reverend James Jones, and Sir Ghillean Prance, the science director of the Eden Project.
They are here to take part in the symposium on the future of the Amazon, arranged by the Orthodox Church.
We have set up a mini open-air studio on a floating dock with a view of the river and the rainforest beyond. Behind us flutter scores of butterflies. And around us, bemused by the spectacle, are the rangers and boatmen of the huge Jau national park.
The minutes flash by and soon we are on air, receiving emailed questions by satellite and beaming back the answers live on BBC World, and recorded to be shown later on News 24.
Sir Ghillean fields questions about the rainforest. It's humbling to be with a man who has personally discovered some 300 new plants in the Amazon and has about 50 named after him. He's passionate about the scale of deforestation and the impact on the people of this region and on the global climate.
The bishop is equally passionate about the controversy over the growing of soya in the Amazon. Many of the soya beans are cultivated in fields carved out of rainforest and are then shipped directly to the bishop's home city. He says his eyes have been opened to the potential damage caused by this trade.
Eye in the sky: "balloon cam" offers a fresh perspective on the problem
All too soon our time is up and our two guests have to leave. The symposium's flotilla of ships is heading back to Manaus. After the long line of vessels has passed, the jungle is quiet once more. We will set off later.
Our time here has been hot, frantic and challenging. But the beauty of this scene is captivating and we've become addicted to the views from our balloon camera.
We're exhausted and need to get home but I know that slipping away downstream, leaving behind the emerald forest, the splash of the pink dolphins, and the changing light on the river, is also likely to be a wrench.
18 JULY: BALLOONING IN THE AMAZON
A tense morning for the BBC News team in the burning heat of the Amazon.
We are victims of our own ambition. Our aim is to give viewers a live panorama of our position on the Rio Negro, one of the mightiest of the Amazon's tributaries, and the best way to achieve this involves some surprisingly old fashioned technology: a balloon from which we'll hang a camera.
How best to get above the trees
Amid the buzz of the countless insects, the stifling humidity, and the stress of trying to keep our promises to editors in London, we unroll the bulky material of a mini-blimp.
We're in the Jau National Park and the rangers who run the place gather to watch in amazement. We're pretty amazed too: this is the part of our plan that has long caused most excitement.
Engineers Martin Doyle and Paul Szeless have worked at double speed to prepare every other element of our broadcasting system - the satellite dish that will connect us to the newsroom and the "mast camera" on top of a 12m extendable tower.
Now it's time to inflate the balloon and see if it will fly. With producer Mark Georgiou filming each step in the process, ropes are attached, helium cylinders are opened and finally it's time for lift-off. But then it's a case of : "Amazon, we have a problem".
There is lift-off but not much. Martin and Paul lighten the balloon's load and pump in more helium. And then a moment of broadcasting history: our latest pet rises gently into the tropical air and soon we're on air, too.
The camera can be remotely controlled so we can show spectacular views from 30m above the canopy. The sweep of the river, the clusters of islands and the dense green of the rainforest all lie revealed below our lens - and our small team in a remote corner of the Amazon managed to share it with millions.
17 JULY: ALL ABOARD
A day of ludicrous extremes. Our first stop is the wooden shack that is home to Jose Amorin and his family.
A few chickens pick at scraps and his grandchildren toss marbles into the dust.
Jose was one of many millions in the region who suffered from the drought that struck last autumn. He lost half his crop and recalls having only enough food to keep everyone going and none spare to sell in the market.
He sits with his wife on a bench under a tree and they calmly peel oranges while we chat.
He hands me an orange which I try to peel while holding my notebook, a process that ends so messily that Jose shoots me a look of disdain. I manage to wash before our next stop: a lavish cruise ship in the capital of the region, Manaus.
The ship is the setting for what must rank as one of the more surreal gatherings I've ever attended.
It's a symposium on the future of the Amazon organised by the so-called "Green Patriarch", the head of the Orthodox Church who has long taken an active interest in environmental issues.
After previous symposia focusing on other threatened waters like the Baltic and the Black Sea, he has now brought together scientists, politicians, and church leaders to investigate the fate of Amazon.
In the chill of an air-conditioned conference room on board the ship, a top table groans with ecclesiastical weight - the Patriarch and his men sporting splendid beards, senior cardinals from the Vatican in white robes, the Bishop of Liverpool in purple.
The speeches are strong - the theme is the Amazon as a source of life - but I find myself gazing out of a window as the clouds darken and a vicious wind hurls rain horizontally across the river itself.
The challenges here are immense and interlocking: an area the size of Wales is chopped down every year; the burning of so many trees adds hugely to the greenhouse gases linked to global warming; global warming itself threatens to shift the weather system and deny the forest the rain it needs to survive.
I think back to Jose and what it might mean for him, but not for long. That night we set off by boat for an overnight journey upstream and the splash of the river sends me to sleep immediately.
16 JULY: SEIZING CONTROL
We can't help standing out in the crowd: two Brits with sunburned faces, carrying a lot of TV equipment and wearing those off-white, explorer-style shirts with countless pockets and vents that all new boys to the tropics are convinced will keep them cool.
It is 0500, the temperature is 27C and I wonder how the shirt salesman would explain why we are so hot and bothered.
We're up early to catch a short flight from Manaus, the capital of Brazil's Amazon region, to Santarem, a fast-growing riverside town.
I soon fall into conversation with the two men beside me, representatives of a large biscuit company, on a tour to drum up new orders. The first topic is Brazil's shame in the World Cup - my two companions recall it all with forensic detail.
Humiliation confirmed, they then ask about me. I explain that I will be reporting on the future of the rainforest, how it faces the twin threats of climate change and large-scale felling. Their faces drop. Look, says one of the biscuit-men, you Europeans chopped down your forest so leave us alone to decide what to do with ours.
I start to explain that since then scientists have established the Amazon's vital role in the global climate, but it is horribly early in the day, a bumpy ride is making me feel queasy and I sense that I am utterly unconvincing and unprepared for the argument to come.
The Americans are getting ready to seize the forest, I am told. Why do you think they have military bases in countries all around us? To fight drugs, I suggest. Ah, comes the reply, that is what they want you to think - really they want to control our rainforest, and you British will help the Americans.
I feel weary at the prospect of anyone even contemplating invading this place. We land in a thunderstorm. We are given umbrellas to shield us from the waves of rain as we walk to the terminal, but the gales blow them inside out.
15 JULY: WELCOME TO THE FOREST
Have I stepped into the heart of dampness or the heat of darkness?
The Amazon rainforest does strange, confusing things to the brain. Never mind global warming; it's my mind that's heading for dangerous temperatures.
From the air, the ocean of trees had looked so stunning - inviting, even innocent, a rolling carpet of brilliant greens. But step inside and the forest is a world of endless shadows and stifling air.
Only the odd trickle of sunlight makes it down through the leaves and creepers to our path. Imagine entering a darkened sauna that has been placed inside a hothouse and you get the idea.
And then picture the surge of adrenaline that comes from discovering that we are not alone. I suddenly find myself enduring a short, sharp lesson in biodiversity.
I'm all for conserving wildlife but some of the creatures here are truly unnerving. Within a minute of arriving, an ant the size of a paper clip falls from a tree and lands on my sleeve.
Seconds later, a particularly muscle-bound type of mosquito, with the burly physique of a wasp, tries to punch through the shirt of cameraman John Boon.
The monster is swiped to the ground by the Brazilian scientist guiding us, Flavio Luizao, who picks it up and points out its proboscis, which resembles one of those particularly large hypodermic needles.
But what really makes us jump is the appearance of a scorpion with attitude. It suddenly appears at our feet, scuttling at steroid-induced speed. You only need to worry if there is a red dot on its back, we are told. Otherwise it won't actually kill you.
And that's all in the first five minutes. The depressing thing is that we are bathed in insect repellent and it is not working. Welcome to the forest, says Flavio with a grin, fruitlessly waving his cap at the swarm around his head.