The last chapter explains how the 2010s became another lost decade in the fight against climate change – as the move to natural gas delayed a transition to more renewable sources of energy.
Engineer Tony Ingraffea, in the 1980s, helped develop a new technique for extracting gas and oil from shale rock, which ultimately became known as 'Fracking'. It was to unleash vast new reserves of fossil fuels and was promoted as a cleaner energy source. But Ingraffea explains how he later came to regret his work when he realized that gas could be even worse for climate change than coal and oil.
Dar-Lon Chang, a former ExxonMobil engineer, speaks for the first time on camera alleging that as the company increased its natural gas operations, it was not sufficiently monitoring methane leaks that were contributing to climate change. Now, after a year of unprecedented wildfires, drought and other climate-related disasters, multiple lawsuits are being brought in US courts in efforts to hold Big Oil legally accountable for the climate crisis.

The climate is changing faster than ever, which is why 'fix our climate' is one of the five goals of the Earthshot Prize. Prince William, Sir David Attenborough and Christiana Figueres highlight inspiring and often unexpected solutions to the challenge. In this film, we'll explain the scale of the problem posed by climate change and will introduce you to some amazing people already working on climate crisis. One of these three finalists will win the Earthshot Prize and get the platform and resources they need to scale their ground-breaking work. Nine more solutions for fixing our climate will receive the same support over the course of this decade.

We routinely talk about healthy food and clean water, but how often do we spare a thought for what enters our lungs? The World Health Organization calls air pollution the silent killer. Air pollution is proven to shorten our lifetimes and it hits the vulnerable - children, the sick and the elderly - hardest of all.
Prince William, Sir David Attenborough and astronaut Naoko Yamazaki hear the personal stories of people who are directly affected by air pollution and show us incredible solutions.

The meteoric rise of renewable energy has consequences for our electricity supply. While coal and gas fired power stations can generate electricity whenever you need it, renewables are intermittent by nature. So we need a backup plan for when the wind stops or the sun goes down.
All over the world, engineers and scientists are racing to solve one key problem; how to safely and efficiently store electricity at a huge scale but at a low cost. The quest is producing some truly remarkable ideas and this episode details three of them.

Across the world, rising demands for food, water and materials have pushed resources to the limit. Many parts of the world have major challenges over fresh water. A lot of soils have a lot of residual pesticides and herbicides. At the same time waste is piling higher. All this demands a new wave of innovation. The challenge is to make more of the things we need without the environmental cost.

This episode is centered around how science, in particular the work of Clair Patterson (voiced in animated sequences by Richard Gere[33]) in the middle of the 20th century, has been able to determine the age of the Earth. Tyson first describes how the Earth was formed from the coalescence of matter some millions of years after the formation of the Sun, and while scientists can examine the formations in rock stratum to date some geological events, these can only trace back millions of years. Instead, scientists have used the debris from meteor impacts, such as the Meteor Crater in Arizona, knowing that the material from such meteors coming from the asteroid belt would have been made at the same time as the Earth. Patterson also examined the levels of lead in the common environment and in deeper parts of the oceans and Antarctic ice, showing that lead had only been brought to the surface in recent times. He would discover that the higher levels of lead were from the use of tetraethyllead in leaded gasoline resulting in government-mandated restrictions on the use of lead.