The environment and wildlife show returns with a celebration of the humble microbe. Tom Heap and Helen Czerski are joined by a ‘microbe explorer’ who travels to some of the Earth’s most hostile environments in search of microbes with a huge appetite for carbon dioxide. They also be visit the crop trial field station of Imperial College London where researchers are studying changes to bacteria in soil that could help agriculture and the environment.

Producer: Emma Campbell

Assistant Producer: Toby Field

Rare Earth is made by BBC Audio Wales and West in association with the Open University.

Seabirds face many challenges - avian flu, plastic pollution, overfishing and climate change have all had an impact - but despite all of this, these resilient birds are surviving and in some cases, thriving. Tom Heap and Helen Czerski explore all things seabird, from the urban kittiwakes of Tyneside to the sea cliffs of Shetland.

They're joined by Adam Nicolson, the author of The Seabird's Cry. He's determined to recover the reputation of the puffin from the cute star of seaside mugs and tea towels to its rightful place as a brave and powerful navigator of the toughest ocean environments.

Mike Dilger, resident nature expert on BBC TV's The One Show, reports from Shetland on the extraordinary colony of storm petrels that breed in the brickwork of Iron Age brochs.

The kittiwakes that nest in the heart of Newcastle and Gateshead are the furthest inland colony in the world. Helen Wilson of Durham University discusses her research on the birds and their developing relationship with the people who live and work alongside them.

Many of Britain's most dramatic seabird colonies breed on the most isolated islands of the west coast of Scotland. Film-maker and adventure leader Roland Arnison has spent the summer in a kayak, paddling from island to island, recording the sounds of thirty species of seabird. He tells Tom and Helen about his Call of the Loon expedition and his dramatic scrapes with riptides, hypothermia and the most predatory of Scottish seabirds- the great skua.

Producer: Alasdair Cross

Rare Earth is a BBC Audio Wales and West production in conjunction with the Open University

Tom Heap and Helen Czerski meet the people with fresh ideas to combat rising sea levels, from Enfield to Indonesia.

Average sea levels across the world are rising fast. That puts 570 cities with a combined population of 800 million people at significant threat of inundation. Add in the impact of extreme rainfall events and you have a huge slice of our urban planet that needs protection from flooding. Tom and Helen are joined by Professor Richard Dawson of Newcastle University who considers the engineering solutions available, from huge chunks of concrete and steel to the clever use of parks and gardens that can slow down the flow of water into the streets.

Emma Howard Boyd, former chair of the Environment Agency, tells them about her London Climate Resilience Review which shines a light on the urgent need to raise the city's embankments and suggests some quirkier options. Could the 160,000 large holes that are dug ever year in London be repurposed as emergency water buffers?

Helen visits New Orleans, 19 years after one of the world's most disastrous urban floods, to meet Dana Eness who leads the Front Yard Initiative which helps city residents floodproof their homes with native flower gardens and rainwater butts. And journalist, Peter Hadfield, discusses his visit to Jakarta, the capital of Indonesia that's sinking fast. There are ambitious plans for new sea defences linked by artificial Dubai-style luxury islands, but the national government has decided to abandon the city in favour of a new capital over 1000km away.

Producer: Alasdair Cross

Assistant Producer: Toby Field

Over the centuries, bottom-trawling activities have transformed our coastal seas both ecologically and physically, mostly for the worse. As the habitat has declined, so has the success of fisheries. Is it time we said goodbye to bottom trawling? Or can we manage our coastal seas more effectively to protect nature and provide seafood and jobs?

Tom Heap and Helen Czerski discuss the issues with a panel of experts.

Producer: Emma Campbell

Assistant Producer: Toby Field and Christina Sinclair

Rare Earth is a BBC Audio Wales and West production in conjunction with the Open University

Is the rise in global wild fires unstoppable? Helen Czerski and Tom Heap discuss the terrifying march of the flames and search for fresh answers. They're joined by John Vaillant, author of the award-wining exploration of Canada's Fort McMurray disaster, 'Fire Weather' and by Dr Stacey New from the Met Office.

Tom and Helen take a look at the ways in which indigenous knowledge is being applied to fire prevention in California and visit the Blodgett Research Forest where experts study the best ways to make America's threatened forests more resilient.

They're also joined by Grant Moir of the Cairngorms National Park to discuss new by-laws banning campfires in the area. Do we need to restrict our freedom in the wilderness to protect it for the future?

Producer: Alasdair Cross

Can meat ever be environmentally friendly, or do we need better substitutes? Helen Czerski and Tom Heap discuss the cutting edge technology being developed to reduce the carbon cost of our diet.

Producer: Emma Campbell

Assistant Producer: Toby Field

Rare Earth is a BBC Audio Wales and West production in conjunction with the Open University

What should we do with our old oil rigs? Can the relics of the fossil fuel age be good for wildlife? Helen Czerski and Tom Heap investigate the future for the steel and concrete that's fuelled the modern age.

Helen visits a highly specialist scrapyard on Teeside which dismantles oil rigs bought ashore at the end of their lives. Tom and Helen discuss whether the rules on what happens to old oil and gas installations in the North Sea should be relaxed to allow some to be turned into artificial reefs. They hear from Professor Matt Frost from Plymouth Marine Laboratory and INSITE, an international project investigating the future for undersea structures; Dr Alethea Madgett a marine ecologist who's researching how old rigs can be used in nature restoration; and Ricky Thomson from the industry body Offshore Energies UK.

Producer: Sarah Swadling

Rare Earth is a BBC Audio Wales and West production in conjunction with the Open University

With the general election now two weeks away, Helen Czerski and Tom Heap take a look at how the environment is featuring on the political agenda. They are joined by a panel of guests: energy and climate commentator Sepi Golzari-Munro; senior policy editor at the independent climate news website Carbon Brief, Simon Evans; Chief Executive of the Wildlife Trusts, Craig Bennett; and environment correspondent for BBC News, Matt McGrath.

Together they take a look through the manifestos of the main political parties, exploring their policies and pledges when it comes to the environment and wildlife. They ask whether green issues are taking a back seat in this general election compared with previous ones - and if so, why? They examine how the parties are talking about the environment in their campaigning, including the language they're using and how they're positioning environmental concerns in relation to other issues such as healthcare and the cost of living. Do politicians see environmental promises as a vote-winner or a vote-loser? We also hear from the polling organisation YouGov, which has carried out research assessing which issues are most important to voters.

Producer: Sarah Swadling

Rare Earth is a BBC Audio Wales and West production in conjunction with the Open University.

Nature-writing is going through a renaissance. What started largely with TV tie-ins has evolved into a genre encompassing books about climate change, the countryside, walking, and off-grid living. For Radio 4's new landmark environment and nature series, Rare Earth, presenters Tom Heap and Helen Czerski are joined on-stage at the Hay Festival by Mark Cocker, Philippa Forrester and Chris Thorogood to discuss the purpose of nature-writing, why it's important, and how nature-writing can help shape our understanding of the natural world. Produced by Emma Campbell for BBC Audio Wales and West in conjunction with the Open University

In the first edition of a new series of Rare Earth Tom Heap and Helen Czerski reveal a new phenomenon- 'Greenhushing'. Big corporations that once trumpeted their green credentials are now staying very quiet about the environment. From the left they've been attacked by green zealots eager to expose greenwashing, when their claims don't stand up to scrutiny. Meanwhile from the right any hint of environmental action is condemned as 'woke'. Better, some business advisors believe, to keep quiet about the issue and avoid offending any of their potential customers or falling foul of new regulations.

Tom and Helen discover how hotel towels inspired the coining of the term greenwash, by ecologist Jay Westerveld. Moving on to greenhushing, they're joined by business experts and PR gurus to consider the broader impact of business and industry disengaging from the core issue of our time. Solutionist Solitaire Townsend explains why she thinks some greenhushing is a good thing. Tom and Helen take a deep dive into what might be driving greenhushing with the former CEO of French food giant Danone, and now head of the International Sustainability Standards Board, Emmanuel Faber, international trade and sustainability expert Dr Rebecca Harding, and journalist turned PR advisor Piers Scholfield.

Producer: Sarah Swadling