Discovery

The second episode in our four-part series Saving the Ocean in which we look at the impact of climate change, overfishing and pollution on ocean environments, and examine the scientific solutions to some of those issues. Presented by Joel Werner from the Australian broadcaster ABC Radio National, the series focuses on the improvements both for marine life and the people who depend on oceans for their livelihoods.In this second programme Joel looks at plans to help conserve sharks in the waters around remote Pacific islands. A shark fin export trade to Asia has provided a lucrative but ultimately unsustainable income for the islanders. And he visits New Zealand, where a high-tech solution has been designed to help sustainably harvest a different valuable export commodity - marine snails. A high demand from Asia for this delicacy has endangered the snails. Joel hears how digital technology is being used to track them to ensure there are enough left to breed. He also sees what tracking technology is revealing a

Saving the Ocean looks at the impact of climate change, overfishing and pollution - and examines the scientific solutions to some of those issues. In the first programme Joel Werner visits Kiribati – an isolated Pacific island group threatened by rising sea levels. They are also facing a range of more immediate problems - a high human population and a shortage of land puts pressure on natural resources. Joel meets the scientists working to keep the population afloat on these tiny coral atolls. He finds out about how this island group is threatened by sea level rise and changing weather patterns - and how in some cases, poor sea defence management is making the erosion of the islands worse.(Image: Low tide reveals the detritus of 50,000 people on South Tarawa, Kiribati, BBC copyright)

Today, 3.5 billion people are alive because of a single chemical process. The Haber-Bosch process takes nitrogen from the air and makes ammonia, from which synthetic fertilizers allow farmers to feed our massive population. Ammonia is a source of highly reactive nitrogen, suitable not just for fertilizer, but also as an ingredient in bomb making and thousands of other applications. We make around 100 million tonnes of ammonia annually - and spread most of it on our fields. But this is a very inefficient way to use what amounts to 1-2% of the planet's energy needs. Only around 20% of fertilizer made ends up in our food. Professor Andrea Sella explores some of the alternative ways we might make fertilizer. Vegetables such as peas and beans, allow certain cells in their roots to become infected by a specific type of bacteria. In return, these bacteria provide them with their own fertilizer. Could we infect the plants we want to grow for food – such as cereals – in a similar way to cut down the climatic and envir

Are you a lark or an owl? Are you at your best in the morning or the evening? Linda Geddes meets the scientists who are exploring the differences between larks and owls. At the University of Surrey's Sleep Research Centre she talks to its director, professor Derk-Jan Dijk, and finds out her own chronotype by filling in a questionnaire. Linda discovers why we have circadian rhythms and why they do not all run at the same rate. Dr Louis Ptacek from the University of California, San Francisco, explains his investigation of the genes of families whose members get up very early in the morning and of those who get up very late. She finds out why our sleep patterns change as we age – teenagers really are not good at getting up in the morning. Professor Mary Carskadon from Brown University explains that although some schools have experimented with a later start there is no plan to put this into universal practice. Linda talks to Professor Til Roenneberg from Ludwig-Maximilians-University Munich about his concept of s

Geoengineering is a controversial approach to dealing with climate change. Gaia Vince explores the process of putting chemicals in the stratosphere to stop solar energy reaching the earth. When volcanoes erupt they put sulphur in the stratosphere. The particles reflect solar rays back into space and the planet cools down. Scientists are suggesting that it could be possible to put sulphur into the stratosphere using specialised aircraft or a very long pipe. But if this was implemented there could be impacts on rainfall and the ozone layer. Another idea is to spray seawater to whiten clouds that would reflect more energy away from the earth. Gaia Vince talks to the researchers who are considering solar radiation management. She also hears from social scientists who are finding out what the public think about the idea and who are asking who should make decisions about implementing this way of cooling the planet.(Photo: The ocean with the sun rising in the horizon)

The Australasian Antarctic Expedition has been retracing the steps of the first expedition to East Antarctica, a century ago. Its leader was Douglas Mawson, one of the great figures of the heroic age of exploration of the frozen continent. In the last of the programmes from the Antarctic, Andrew Luck-Baker reports on the 10 days the scientists, tourists and crew of the ship, the Academik Shokalskiy, spent locked in the ice and their eventual release via helicopters from a Chinese ice breaker to an Australian vessel.

Alok Jha and Andrew Luck-Baker continue to follow the scientists on the ongoing Australasian Antarctic Expedition 2013. They go out on fieldwork trips with the researchers studying how the wildlife that lives in this inhospitable environment is responding to climate change. Zoologist Tracy Rogers searches for leopard seals with underwater microphones. From a safe distance she takes a small sample from a Weddell seal to find out what it’s been eating. Ornithologist Kerry-Jayne Wilson discovers that an iconic breeding colony of Adelie penguins at Cape Denison, the rocky area where Douglas Mawson built his expedition hut, has depleted numbers as the fast ice has grown. Producer: Andrew Luck-BakerImage: Ice-blocked bow of the Shokalskiy and expedition doctor Andrew Peacock

Alok Jha and Andrew Luck-Baker continue to follow the scientists on the ongoing Australasian Antarctic Expedition 2013. Ice, the oceans and climate change are the themes this week as one of the expedition scientists makes a troubling finding. Moored in Commonwealth Bay in East Antarctic, the expedition’s oceanographer Erik van Sibble discovers a stunning difference in the nature of the water beneath the sea ice. Although it is a preliminary finding, the consequences for the motions of the world’s oceans and climate change could be dramatic. With thanks to AAE volunteer scientist Terry Gostlow for sound recording assistance.

Join the scientists of the Australasian Antarctic Expedition 2013, as they go about their experiments and seek adventure at the windiest place on earth.This location was named the Land of Blizzard by Douglas Mawson, the Antarctic pioneer who was the first to explore this remote and desolate place 100 years ago.Between 1911 and 1914, Douglas Mawson explored a fiercely harsh part of Antarctica while the more celebrated Scott and Amundsen raced to the South Pole, elsewhere on the frozen continent. Mawson’s expedition was dedicated to scientific study in the early Heroic Age of Antarctic Exploration but his journey was fraught with horror and danger. The 2013 Australasian Antarctic Expedition aims to repeat many of Mawson’s investigations around Commonwealth Bay and Cape Denison in East Antarctica where the original team set up their base. This remote area hasn’t been studied systematically for 100 years, so the expedition will reveal any changes that have taken place as a result of climate change.

Quentin Cooper takes a look at the new materials that can mend themselves. Researchers are currently developing bacteria in concrete which, once awakened, excrete lime to fill any cracks. In South America you can choose a car paint that heals its own scratches. And there are even gold atoms which can migrate to mend tiny breaks in jet turbine blades.Engineers normally design things so the likelihood of breaking is minimised. But by embracing the inevitability of breakage, a new class of materials which can mend cracks and fissures before you can see them may extend the lives of our cars, engines, buildings and aeroplanes far beyond current capability.(Image: Presenter, Quentin Cooper, BBC Copyright)

We like to think that we are in control of our lives, of what we do, think and feel. But, as Geoff Watts discovers, scientists are now revealing that this is just an illusion. A simple magic trick reveals just how limited our conscious awareness of the world is, and how easy it is to fool us. So if our conscious brain can cope with so little, what is responsible for the rest? Science is starting to reveal the crucial role of a silent partner inside our heads, that we are completely unaware of – our unconscious. In this programme, Geoff enlists the help of, not just brain scientists but, a conjuror and a musician to reveal the pivotal role the unconscious plays in pretty much everything we do, think and feel. This new-found knowledge is enabling scientists to harness its powers for both medical and military benefit.

The human gut has around 100 trillion bacterial cells from up to 1,000 different species. Every person's microbiota (the body's bacterial make-up) is different as a result of the effects of diet and lifestyle, and the childhood source of bacteria. What is it about the microbes in our guts that can have such an impact on our lives? Scientists are learning more and more about the importance of these bacteria, as well as the viruses, fungi and other microbes that live in our gastrointestinal tracts. Without them, our digestion, immune system and overall health would be compromised. Adam Hart talks to researchers who are discovering how important a balanced and robust gut microflora is for our health. And he asks how this can be maintained and what happens when things go wrong.(Image: Gut Microbiota Copyright: Getty Images)

Journalist and numbers obsessive Alex Bellos travels around India to explore the fundamental numerical gifts which early Indian mathematicians gave to the world and asks whether the great religions of ancient India - Hinduism, Buddhism and Jainism - had any part in their origins. The number system which the world uses today originated in India in the early centuries of the first millennium AD. It is usually called the Arabic numeral system, but in the Middle East the scheme employing the symbols 0 to 9 is correctly referred to as the Indian system. The designation of zero as a number in its own right by South Asian thinkers was arguably the greatest conceptual leap in the history of mathematics. During his numerical odyssey, Alex visits a temple in Gwalior, containing the earliest zero in India with a known date. He is also granted an audience with one of Hinduism's most revered gurus, who is also an author of books on numbers. His Holiness, the Shankaracharya of Puri tells Alex that the study of mathematics

Australian geneticist Jenny Graves discusses her life pursuing sex genes in her country's weird but wonderful fauna, the end of men and singing to her students in lectures.(Image: Jenny Graves, BBC copyright)

Life on earth has gone through a series of mass extinctions. Mike Benton talks about his fascination with ancient life on the planet and his work on the Bristol Dinosaur Project.Image: Mike Benton BBC Copyright

Joanna Haigh, Professor of Atmospheric Physics at Imperial College, London, studies the influence of the sun on the Earth's climate using data collected by satellites. She talks to Jim al-Khalili about how she got started on her career in climate physics: she can trace her interest in it back to her childhood when she built herself a home weather station. Jo Haigh explains why we need to know how the sun affects the climate: it's so scientists can work out what contribution to warming is the result of greenhouse gases that humans produce, and what is down to changes in the energy coming from the sun. She has sat on the Intergovernmental Panel on Climate Change and discusses with Jim how it delivers its reports. And as a prominent scientist who speaks out about the dangers of increasing man made greenhouse gases in the atmosphere, she explains how she responds to climate change deniers. Image: Joanna Haigh Credit: BBC

Russell Foster, professor of circadian neuroscience at Oxford University, is obsessed with biological clocks. He talks to Jim al-Khalili about how light controls our wellbeing from jet lag to serious mental health problems. Professor Foster explains how he moved from being a poor student at school to the scientist who discovered a new way in which animals detect light. Image: Russell Foster Copyright: BBC

Adam Hart investigates yet another threat to the ash trees of Europe. In the last programme he found out about the latest research developments to save ash trees from ash dieback, a disease that has already devastated trees across Europe, but now it seems that another threat could be on its way from Russia – the emerald ash borer. This beetle already targets ash trees in the USA and kills 99% of the trees it infests. But, what is it, how great is the threat and is there any way to stopping it spreading to Europe?Image: Emerald Ash Borer Traces Credit: Cornelia Schaible

Professor Adam Hart looks at the disease that has devastated ash trees in Europe – ash dieback. Over the last 20 years the fungus that causes ash dieback has been spreading westwards across the continent and last year it was found in the UK for the first time. At the moment there is no cure for the disease and only a tiny fraction of trees seem to be able to survive it. In this programme, he investigates the very latest scientific research into this deadly disease and asks if it will be enough to save this important species.(Image: Professor Adam Hart in Trolleholm seed orchard in Sweden where ash dieback has infected many of the trees. Credit: BBC)

Fracking for gas is highly controversial in the US and the UK as it has been accused of contaminating water courses and causing earthquakes. Yet it provides a cheap source of energy. Beneath England there are thought to be considerable amounts of shale gas and the UK government is considering whether to allow fracking in these areas. Already there is opposition from residents, concerned about pollution and earth tremors. Gaia Vince talks to scientists to find out what fracking involves and what impact it has on the environment, and she discovers what other countries can learn from the pioneers of the technology, the United States.(Image: Views of the Cuadrilla Fracking Site at Balcombe. Credit: WPA Pool, Getty)