This year, millions of people around the world mobilised in protest to highlight the dire emergency facing our planet. Could 2019 prove to be the year when talk turned to action on the climate crisis?
We looked back at some of the biggest stories of the year in science and the environment.
In 2019, the reaction to the ongoing climate crisis switched up another gear. Inspired by Swedish activist Greta Thunberg, the climate strike movement exploded this year. Millions took part in mass protests during the course of the year in countries as diverse as Australia, Uganda, Colombia, Japan, Germany and the UK.
Greta chose to make a statement when she sailed - rather than flew - to a UN climate meeting in New York. Summing up the trajectory for many who have joined popular climate movements, she told chief environment correspondent Justin Rowlatt: "I felt like I was the only one who cared about the climate and ecological crisis... it makes me feel good that I'm not alone in this fight."
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The UK's Extinction Rebellion (XR) was making its point through non-violent direct action in 2019. The group, which aims to compel government action on climate change, occupied five prominent sites across central London in April 2019. Notably, they parked a pink boat in the middle of busy Oxford Circus bearing the phrase "Tell the Truth".
This year also saw the UK's Parliament - along with individual councils around the country - declare a climate emergency, granting what had been one of XR's key demands.
But there were also setbacks to political efforts aimed at reducing greenhouse gas emissions. The US - one of the world's top emitters - began the process of pulling out of the Paris Agreement. This deal was conceived in 2015 with the intention of keeping the global average temperature to below 2C. President Donald Trump said the pact was bad for the US economy and jobs.
This year's UN climate meeting - COP25 - ended in a deal many described as disappointing. The result means that the onus now falls on the UK to resolve many of the most challenging questions at COP26 in Glasgow in 2020.
In April, astronomers released the much anticipated first image of a black hole. This is a region of space from which nothing, not even light, can escape. The picture was taken by a network of eight telescopes across the world and shows what was described as "the heavyweight champion of black holes".
The 40 billion km-wide, spacetime-warping monster features an intense halo, or "ring of fire", around the black hole caused by superheated gas falling in.
The image caused a sensation and raised the profile of one computer scientist working on the project. 29-year-old Dr Katie Bouman helped develop an algorithm that allowed the image to be created. A picture of her with hands clasped over her mouth, barely containing her excitement at the astronomical picture on her laptop, quickly went viral.
But her fame led to trolling, with some accusing her of hogging credit for a male colleague's work. That team member, Dr Andrew Chael, quickly came to her defence. In an interview for the BBC 100 Women series, Dr Bouman said: "At first I was really taken aback by it. But... I do think it is important that we highlight the women in these roles."
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Two major reports from the UN's climate science body revealed in sharp relief the extent to which humanity is ravaging Earth's land surface and her oceans. The first of these documents from the IPCC (Intergovernmental Panel on Climate Change) warned that we must stop abusing the land if catastrophic climate change is to be avoided.
The report outlined how our actions were degrading soils, expanding deserts, flattening forests and driving other species to the brink of extinction. Scientists involved in the UN process also explained that switching to a plant-based diet could help combat climate change.
The second report, dealing with the world's oceans and frozen regions, detailed how waters are rising, ice is melting and species are being forced to move. As co-ordinating lead author Dr Jean-Pierre Gattuso said, "The blue planet is in serious danger right now, suffering many insults from many different directions and it's our fault." The authors believe that the changes we've set in motion are coming back to haunt us. Sea level rise will have profound consequences for low-lying coastal areas where almost 700 million people live.
On 1 January, Nasa's New Horizons spacecraft made the most distant ever exploration of a Solar System object. Launched all the way back in 2006, it performed its primary task - a flyby study of the Pluto system - in 2015. But with plenty of gas still in the tank, mission scientists directed the spacecraft towards a new target, an object called 2014 MU 69.
MU 69, later dubbed Ultima Thule, and more recently Arrokoth, may be fairly typical of the primitive, icy objects occupying a distant zone of our Solar System known as the Kuiper Belt.
There are hundreds of thousands of objects out there like it, and their frigid state holds clues to how all planetary bodies came into being some 4.6 billion years ago.
Earlier this year, scientists presented details of what they had found at a major conference in Houston. They had determined that Arrokoth's two lobes formed when distinct objects collided at just 2-3m/s, about the speed you would run into a wall, according to team member Kirby Runyon.
In September, former UK chief scientist Sir David King said he was scared by the faster-than-expected pace of climate-related changes. One of the most shocking examples this year of the extreme events Sir David spoke of was surely the record ice melt in Greenland.
In June, temperatures soared well above normal levels in the Danish territory, causing about half its ice sheet surface to experience some melting. As David Shukman reported on his trip to the region, during 2019 alone, it lost enough ice to raise the average global sea level by more than a millimetre.
Underlining the rapid nature of the change, he returned to a glacier he had filmed in 2004 to find that it had thinned by as much as 100m over the period.
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Greenland's ice sheet stores so much frozen water that if the whole of it melted, it would raise sea levels worldwide by up to 7m. Although that would take hundreds or thousands of years, polar scientists told the American Geophysical Union meeting in December that Greenland was losing its ice seven times faster than in the 1990s.
Prof Andy Shepherd, of Leeds University, said: "The simple formula is that around the planet, six million people are brought into a flooding situation for every centimetre of sea-level rise."
While civilisation-threatening asteroids are a staple of the movies, the probability of a sizeable space rock hitting our planet is very low. But as the dinosaurs found out, the risk does increase with time. Some 19,000 near-Earth asteroids (NEAs) are being monitored, but many lurk undetected by telescopes, so there is always potential for a bolt-from-the-blue.
In March, Nasa scientists told the Lunar and Planetary Science Conference (LPSC) that a big fireball had exploded in Earth's atmosphere at the end of 2018. The space rock barrelled in without warning and detonated with 10 times the energy released by the Hiroshima atomic bomb.
Luckily, the rock blew up over the sea off Russia's remote Kamchatka Peninsula. But an outburst that size could have had serious consequences had it occurred nearer the ground, over a densely populated area.
Then in July, an asteroid the size of a football field buzzed Earth, coming within 65,000km of our planet's surface - about a fifth the distance to the Moon. The 100m-wide rock was detected just days before it passed Earth.
Meanwhile, two robotic spacecraft have been examining different NEAs close-up. Scientists working on Japan's Hayabusa mission reported that their asteroid, Ryugu, was made of rubble blasted off a bigger object. And the US Osiris-Rex spacecraft detected plumes of particles erupting from the surface of its target, Bennu.
The gas sulphur hexafluoride (SF6) isn't a household name. But as the most powerful greenhouse gas known to science, it could play an increasingly important role in discussions about climate change.
As environment correspondent Matt McGrath reported in September, levels are on the rise as an unintended consequence of the boom in green energy. The cheap, non-flammable gas is used to prevent short circuits and fires in electrical switches and circuit breakers known collectively as "switchgear".
As more wind turbines are built around the world, more of these electrical safety devices are being installed. The vast majority use SF6.
Although overall atmospheric concentrations are small for now, the global installed base of SF6 is expected to grow by 75% by 2030. Worryingly, there's no natural mechanism that destroys or absorbs the gas once it's been released.
Quantum computers hold huge promise. The "classical" machines we use today compute in much the same way as we do by hand. Quantum computers promise faster speeds and the ability to solve problems that are beyond even the most powerful conventional types. But scientists have struggled to build devices with enough units of information (quantum bits) to make them competitive with classical computers.
A quantum machine had not surpassed a conventional one until this year. In October, Google announced that its advanced quantum processor, Sycamore, had achieved "quantum supremacy" for the first time. Researchers said it had performed a specific task in 200 seconds that would take the world's best supercomputer 10,000 years to complete.
IBM, which has been working on quantum computers of its own, questioned some of Google's figures. But the achievement represents an important step towards fulfilling some of the predictions made for
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The big science and environment stories of 2019 - BBC News
- Google claims to have invented a quantum computer, but IBM begs to differ - The Conversation CA - January 22nd, 2020
- Xanadu Receives $4.4M Investment from SDTC to Advance its Photonic Quantum Computing Technology - Quantaneo, the Quantum Computing Source - January 22nd, 2020
- U of T's Peter Wittek, who will be remembered at Feb. 3 event, on why the future is quantum - News@UofT - January 17th, 2020
- Quantum Computing Technologies Market 2019, Size, Share, Global Industry Growth, Business Statistics, Top Leaders, Competitive Landscape, Forecast To... - January 17th, 2020
- This Week In Security: Windows 10 Apocalypse, Paypal Problems, And Cablehaunt - Hackaday - January 17th, 2020
- Kitchener's Angstrom Engineering is making a quantum leap with its next-generation technology - TheRecord.com - January 17th, 2020
- Xanadu Receives $4.4M Investment from SDTC to Advance its Photonic Quantum Computing Technology - Yahoo Finance - January 16th, 2020
- The dark side of IoT, AI and quantum computing: Hacking, data breaches and existential threat - ZDNet - January 16th, 2020
- 'How can we compete with Google?': the battle to train quantum coders - The Guardian - January 16th, 2020
- IBM heads US patent list for 27th consecutive year - Technology Decisions - January 16th, 2020
- New Technique May Be Capable of Creating Qubits From Silicon Carbide Wafer - Tom's Hardware - January 14th, 2020
- The hunt for the 'angel particle' continues - Big Think - January 13th, 2020
- How to verify that quantum chips are computing correctly - MIT News - January 13th, 2020
- Googles Quantum Supremacy will mark the End of the Bitcoin in 2020 - The Coin Republic - January 13th, 2020
- Bleeding edge information technology developments - IT World Canada - January 13th, 2020
- Jeffrey Epstein scandal: MIT professor put on leave, he 'failed to inform' college that sex offender made donations - CNBC - January 10th, 2020
- The teenager that's at CES to network - Yahoo Singapore News - January 10th, 2020
- AI, ML and quantum computing to cement position in 2020: Alibabas Jeff Zhang - Tech Observer - January 8th, 2020
- Perspective: End Of An Era | WNIJ and WNIU - WNIJ and WNIU - January 8th, 2020
- Volkswagen carried out the world's first pilot project for traffic optimization with a quantum computer - Quantaneo, the Quantum Computing Source - January 6th, 2020
- The 12 Most Important and Stunning Quantum Experiments of 2019 - Livescience.com - December 31st, 2019
- Physicists Just Achieved The First-Ever Quantum Teleportation Between Computer Chips - ScienceAlert - December 31st, 2019
- Quantum Supremacy and the Regulation of Quantum Technologies - The Regulatory Review - December 31st, 2019
- The Best of Science in 2019 - Research Matters - December 31st, 2019
- Technology And Society: Can Marketing Save The World? - Forbes - December 31st, 2019
- From the image of a black hole to 'artificial embryos', 2019 was the year of many firsts in science - Economic Times - December 28th, 2019
- Information teleported between two computer chips for the first time - New Atlas - December 26th, 2019
- Same Plastic That Make Legos Could Also Be The Best Thermal Insulators Used in Quantum Computers - KTLA Los Angeles - December 26th, 2019
- Quanta's Year in Math and Computer Science (2019) - Quanta Magazine - December 26th, 2019
- 2019 EurekAlert! Trending Release List the most international ever - Science Codex - December 26th, 2019
- Could quantum computing be the key to cracking congestion? - SmartCitiesWorld - December 15th, 2019
- ProBeat: AWS and Azure are generating uneasy excitement in quantum computing - VentureBeat - December 15th, 2019
- Will quantum computing overwhelm existing security tech in the near future? - Help Net Security - December 15th, 2019
- Quantum expert Robert Sutor explains the basics of Quantum Computing - Packt Hub - December 15th, 2019
- Traditional cryptography doesn't stand a chance against the quantum age - Inverse - December 15th, 2019
- China is beating the US when it comes to quantum security - MIT Technology Review - December 15th, 2019
- Technology to Highlight the Next 10 Years: Quantum Computing - Somag News - December 15th, 2019
- Quantum Trends And The Internet of Things - Forbes - December 6th, 2019
- Quantum supremacy is here, but smart data will have the biggest impact - Quantaneo, the Quantum Computing Source - December 6th, 2019
- Beer With Bella: Tyson Yunkaporta - The New York Times - December 6th, 2019
- The New Cold War? Its With China, and It Has Already Begun - The New York Times - December 2nd, 2019
- How Countries Are Betting on to Become Supreme in Quantum Computing - Analytics Insight - December 2nd, 2019
- Study: Our universe may be part of a giant quantum computer - The Next Web - November 28th, 2019
- First quantum computing conference to take place in Cambridge - Cambridge Independent - November 28th, 2019
- Threat of quantum computing hackathon to award $100,000 - App Developer Magazine - November 28th, 2019
- World High Performance Computing (HPC) Market Oulook Report, 2019-2024 - HPC Will Be Integral to Combined Classical & Quantum Computing Hybrid... - November 28th, 2019
- ETU "LETI" first won the Bertrand Meyer Award - QS WOW News - November 28th, 2019
- Global Quantum Computing Market is Set to Experience Revolutionary Growth With +25% CAGR by 2025 | Top Players D-Wave Systems Inc., QX Branch, Google... - November 28th, 2019
- Japan plots 20-year race to quantum computers, chasing US and China - Nikkei Asian Review - November 23rd, 2019
- A super cover illustration highlights superconductivity research - The Mix - November 23rd, 2019
- The future that graphene built - Knowable Magazine - November 23rd, 2019
- New Berlin foundation turns AI into immersive art - Art Newspaper - November 23rd, 2019
- Maryanna Saenko and Steve Jurvetson of Future Ventures talk SpaceX, the Boring Co. and . . . ayahuasca - TechCrunch - November 23rd, 2019
- Quantum Hackathon With $100,000 Prize Receives Overwhelming Response - Yahoo Finance - November 22nd, 2019
- Quantum Computing: Challenges, Trends and the Road Ahead - CMSWire - November 20th, 2019
- Researchers Have Achieved a New Level of Quantum Supremacy - TechDecisions - November 20th, 2019
- Will quantum computers revolutionize the world? The Courier - The Courier - November 20th, 2019
- Reality is subjective to the observer - scientists make stunning claim in quantum study - Express.co.uk - November 20th, 2019
- Geeking Out With Legendary Futurist and Investor Steve Jurvetson - mySanAntonio.com - November 20th, 2019
- Hedera Hashgraph (HBAR) Founder Says Quantum Computing Is Not a Threat to Cryptocurrency, Although That Claim Is Debatable Crypto.IQ | Bitcoin and... - November 18th, 2019
- Innovation Focused Firms Issue Open Call for Hackers - IndustryWeek - November 18th, 2019
- Quantum computer - Simple English Wikipedia, the free ... - October 11th, 2019
- Topological quantum computer - Wikipedia - October 11th, 2019
- What is a quantum computer? Explained with a simple example. - September 11th, 2019
- Qubits and Defining the Quantum Computer | HowStuffWorks - September 5th, 2019
- For a Split Second, a Quantum Computer Made History Go ... - May 13th, 2019
- Noisy Quantum Computers Could Be Good for Chemistry Problems ... - April 11th, 2019
- What is a Quantum Computer? - Definition from Techopedia - April 11th, 2019
- What Is a Quantum Computer? | JSTOR Daily - April 11th, 2019
- Measuring Quantum Computer Power With IBM Quantum Volume ... - April 9th, 2019
- Explainer: What is a quantum computer ... - March 24th, 2019
- What Can We Do with a Quantum Computer? | Institute for ... - March 7th, 2019
- Qubit - Wikipedia - February 25th, 2019
- Quantum computer | computer science | Britannica.com - January 10th, 2019
- IBMs new quantum computer is a symbol, not a breakthrough - January 9th, 2019
- IBM unveils the world's first quantum computer that ... - January 9th, 2019
- Were Close to a Universal Quantum Computer, Heres Where We're At - November 28th, 2018
- Schrdinger's Killer App: Race to Build the World's First ... - August 7th, 2018
- How Quantum Computers Work - May 3rd, 2018
- This is what a 50-qubit quantum computer looks like - January 15th, 2018