As a symbol of the extremes the world is prepared to go to feed its addiction to oil, the biggest and most complex civil trial in history is a blazing one. On Monday, barring a last minute settlement, BP and its partners in the Deepwater Horizon oil disaster will face 120,000 individuals who lost their livelihoods, plus the US federal government and states of Louisiana and Alabama. There are $40bn of damages and penalties at stake.

But has the race to the bottom of the oceans and the ends of the Earth in search of oil and gas slowed in the face of such colossal legal and financial risk? It has barely checked its step.

This is a story of superlatives. With unknowing hubris, Transocean, the owner of the Deepwater Horizon rig, trumpeted its world-record drilling depth of almost seven miles in September 2009. “Congratulations to everyone involved,” said CEO Robert Long at the time, noting the “intensive planning and focus on effective operations by BP and the drilling crews”. Just seven months later catastrophe struck: 11 men died and the US had its worst ever offshore oil spill on its hands.

Yet, after a brief pause, business has not just returned to normal in the Gulf of Mexico, but been turbo-charged. There are now 39 oil rigs operating in its deep seas, about a third more than before the Deepwater disaster. Elsewhere, exploration has surged further and deeper into the oceans. Five months after Deepwater erupted, the Brazilian oil giant Petrobras achieved another superlative, the world’s largest-ever share offering, which raised $67bn to fund its exploitation of the vast, deep and ultra-deep oil fields off its coast. But even this is not the region that has analysts bubbling with most excitement. Africa’s west coast, from Angola to Congo to Nigeria, has the world’s richest fields.

These contributions to the world’s fuel tanks will be topped up by a list of places that reads like a brochure for adventurous travellers – Egypt, Indonesia, Equatorial Guinea, the Phillipines, India and Mauritania – as well as the UK’s own fields in the deep blue off Shetland and perhaps the Falklands. While the Deepwater plaintiffs’ 340 lawyers and their opponents prepare to tackle 72m pages of evidence in a New Orleans court room, the world’s reliance on oil from miles under the sea also piles up. A fifth of all offshore oil is now dredged from the depths and this is expected by the industry to rise to over half by the end of the decade and two-thirds by 2030.

At this point I hope you are wondering why the world appears content relying for oil – its economic lifeblood – on extraordinary feats of engineering performed in ever-more extreme locations on Earth. If you weren’t, consider the march northwards into the Arctic, the harshest and most fragile environment on the planet, led by Norway.

The reason for this calm reliance on everyday technical miracles is, unlike the Deepwater court case, devastatingly simple: it is still cheap. Despite costing between four and eight times more to pump up than onshore oil, oil from the depths remains highly profitable. Global oil prices are being driven hard by the people from Beijing to Bangalore getting behind the wheel, with the number of cars on the world’s road expected to double to 1.7bn in 20 years. It is not impossible that plumbing the depths will become a little less attractive if BP, Transocean and the others emerge from their legal labyrinth with a bill of $40bn. But would oil majors really be held to account for disasters in the same way by nations whose GDP is dwarfed by the companies’ wealth? I think not.

Deep water drilling is a hostage to fortune in the short term, especially in locations lacking the resources of the US to clean up and the good fortune of the balmy Gulf waters to degrade spilt oil quickly. In the long term, we will run out of space in the atmosphere for climate-warming carbon dioxide well before we run out of oil and gas. But if money is fuelling the submarine adventuring of ExxonMobil, Shell, BP, Chevron and others, money might just curb it too. The colossal global subsidies for fossil fuels – at least half a trillion dollars in 2010 – are starting to look vulnerable. The UN, G20, International Energy Agency and Barack Obama would all like to torch them, with Obama stating this month: “We need to end the subsidies for oil companies and double down on clean energy.”

The New Orleans court case will push the boundaries of the US legal system and corporate responsibility. But oil exploration will continue to push the boundaries of the planet, until the cost of failure exceeds the prize of success.

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The scientist who has borne the full brunt of attacks by climate change deniers, including death threats and accusations of misappropriating funds, is set to hit back.

Michael E. Mann, creator of the “hockey stick” graph that illustrates recent rapid rises in global temperatures, is to publish a book next month detailing the “disingenuous and cynical” methods used by those who have tried to disprove his findings. The Hockey Stick and the Climate Wars is a startling depiction of a scientist persecuted for trying to tell the truth.

Among the tactics used against Mann were the theft and publication, in 2009, of emails he had exchanged with climate scientist Professor Phil Jones of East Anglia University. Selected, distorted versions of these emails were then published on the internet in order to undermine UN climate talks due to begin in Copenhagen a few weeks later. These negotiations ended in failure. The use of those emails to kill off the climate talks was “a crime against humanity, a crime against the planet,” says Mann, a scientist at Penn State University.

In his book, Mann warns that “public discourse has been polluted now for decades by corporate-funded disinformation – not just with climate change but with a host of health, environmental and societal threats.” The implications for the planet are grim, he adds.

Mann became a target of climate deniers’ hate because his research revealed there has been a recent increase of almost 1°C across the globe, a rise that was unprecedented “during at least the last 1,000 years” and which has been linked to rising emissions of carbon dioxide from cars, factories and power plants. Many other studies have since supported this finding although climate change deniers still reject his conclusions.

Mann’s research particularly infuriated deniers after it was used prominently by the UN’s Intergovernmental Panel on Climate Change (IPCC) in one of its assessment reports, making him a target of right-wing denial campaigners. But as the 46-year-old scientist told the Observer, he only entered this research field by accident. “I was interested in variations in temperatures of the oceans over the past millennium. But there are no records of these changes so I had to find proxy measures: coral growth, ice cores and tree rings.”

By studying these he could trace temperature fluctuations over the past 1,000 years, he realised. The result was a graph that showed small oscillations in temperature over that period until, about 150 years ago, there was a sudden jump, a clear indication that human activities were likely to be involved. A colleague suggested the graph looked like a hockey stick and the name stuck. The results of the study were published in Nature in 1998. Mann’s life changed for ever.

“The trouble is that the hockey stick graph become an icon and deniers reckoned if they could smash the icon, the whole concept of global warming would be destroyed with it. Bring down Mike Mann and we can bring down the IPCC, they reckoned. It is a classic technique for the deniers’ movement, I have discovered, and I don’t mean only those who reject the idea of global warming but those who insist that smoking doesn’t cause cancer or that industrial pollution isn’t linked to acid rain.”

A barrage of intimidation was generated by “a Potemkin village” of policy foundations, as Mann puts it. These groups were set up by privately-funded groups that included Koch Industries and Scaife Foundations and bore names such as the Cato Institute, Americans for Prosperity and the Heartland Institute. These groups bombarded Mann with freedom of information requests while the scientist was served with a subpoena by Republican congressman Joe Barton to provide access to his correspondence. The purported aim was to clarify issues. The real aim was to intimidate Mann.

In addition, Mann has been attacked by Ken Cuccinelli, the Republican attorney general of Virginia who has campaigned to have the scientist stripped of academic credentials. Several committees of inquiry have investigated Mann’s work. All have exonerated him.

Thousands of emails have been sent to Mann, many deeply unpleasant. “You and your colleagues… ought to be shot, quartered and fed to the pigs along with your whole damn families,” said one. “I was hopin [sic] I would see the news and you commited [sic] suicide,” ran another.

Yet all that Mann had done was publish to a study suggesting, in cautious terms, that Earth had started to heat up unexpectedly in the past few decades.

“On one occasion, I had to call the FBI after I was sent an envelope with a powder in it,” Mann adds. “It turned out to be cornmeal but again the aim was intimidation. I ended up with police security tape all over my office doors and windows. That is the life of a climate scientist today in the US.”

Mann insists he will not give up. “I have a six-year-old daughter and she reminds me what we are fighting for.” Indeed, Mann is generally optimistic that climate change deniers and their oil and coal industry backers have overstepped the mark and goaded scientists to take action. He points to a recent letter, signed by 250 members of the US National Academy of Science, including 11 Nobel laureates, and published in Science. The letter warns about the dangers of the current attacks on climate scientists and calls “for an end to McCarthy-like threats of criminal prosecution against our colleagues based on innuendo and guilt by association, the harassment of scientists by politicians seeking distractions to avoid taking action, and the outright lies being spread about them.”

“Words like those give me hope,” says Mann.

The Hockey Stick and the Climate Wars will be published by Columbia University Press in April