2030

Sự nóng lên toàn cầu tiếp tục gia tăng

Sự nóng lên toàn cầu vào năm 2030 hiện đã đạt 1,3 ° C (2,3 ° F) so với mức trung bình giữa thế kỷ 20 và tiếp tục tăng. * Trong đợt El Niño tiếp theo, nó sẽ vượt ngưỡng 1,5 ° C (2,7 ° F) được thống nhất tại Hiệp định khí hậu Paris năm 2015.

Những năm gần đây đã chứng kiến những đợt nắng nóng chưa từng có, hạn hán, lũ lụt, cháy rừng, lốc xoáy nhiệt đới và các thảm họa khác trên khắp thế giới. Thiệt hại kinh tế do các sự kiện liên quan đến thời tiết vào năm 2030 lớn hơn 25% so với chỉ một thập kỷ trước đó, trung bình hơn 250 tỷ đô la mỗi năm. *

Giữa cảm giác cấp bách ngày càng sâu sắc, hoạt động vì môi trường hiện đang tăng lên mức chưa từng thấy trước đây. Điều này bao gồm việc nhắm mục tiêu trực tiếp và phá hoại cơ sở hạ tầng nhiên liệu hóa thạch, cùng với các chiến dịch ngày càng rầm rộ để kích hoạt những thay đổi trong hành vi và lối sống của công chúng. Vào đầu những năm 2020, các hành động phản đối đã bị tội phạm hóa ngày càng tăng ở một số quốc gia. Với các phong trào xanh cực đoan hơn đã xuất hiện kể từ đó, các biện pháp này hiện đang tiến thêm một bước nữa để phân loại một số nhóm là các tổ chức khủng bố hoàn toàn. Ở Nam Mỹ và các khu vực khác, các nhà hoạt động môi trường cản trở hoạt động kinh doanh nông nghiệp, đập thủy điện, khai thác mỏ và khai thác gỗ đang bị sát hại với số lượng lớn hơn bao giờ hết.

Sau đại dịch COVID-19, lượng phát thải khí nhà kính trên toàn thế giới đã giảm tạm thời. Từ mức cao kỷ lục 52 gigatonnes (Gt) tương đương CO2 (có nghĩa là tổng hợp các khí CO2, CH4, N2O và F), chúng đã giảm xuống dưới 49,5 Gt vào năm 2020. Tuy nhiên, tăng trưởng tiếp tục trong những năm tiếp theo và sớm phục hồi trở lại trước mức độ đại dịch. Các nhà lãnh đạo thế giới đã công bố các mục tiêu khí hậu đầy tham vọng hơn, đồng thời phê duyệt các dự án dầu khí mới và tiếp tục cung cấp các khoản trợ cấp khổng lồ cho ngành công nghiệp nhiên liệu hóa thạch.

Mặc dù đã đạt được nhiều tiến bộ trong việc làm chậm tốc độ phát thải - với những dấu hiệu cho thấy đỉnh có thể đang đến gần - nhưng chúng vẫn tiếp tục tăng vào năm 2030. * Những cam kết tại các hội nghị thượng đỉnh về khí hậu đã được chứng minh là không đủ để hạn chế nhiệt độ trung bình toàn cầu ở mức bền vững. Thế giới vẫn đang trên đà ấm lên 2 ° C vào những năm 2040 và gần 3 ° C vào cuối thế kỷ này.

Ectogenesis is transforming reproductive rights

Ectogenesis – the growth of mammalian embryos in artificial environments – was first described in 1924 by British scientist J.B.S. Haldane. His essay, Daedalus; or, Science and the Future, was regarded as shocking science fiction at the time, but later proved to be remarkable in having predicted many scientific advances. Haldane was a friend of author Aldous Huxley, whose famous novel Brave New World (1932) anticipated similar developments in reproductive technology.

In 1953, a transient biochemical pregnancy was reported by Australian researchers who extracted an intact fertilised egg. It was followed by in vitro fertilisation (IVF) six years later enabling the birth of a live rabbit. The first human pregnancy through IVF occurred in 1973 – though it only lasted for a few days. A major milestone was finally reached in 1978, when Louise Brown became the first "test tube baby" having been conceived on a petri dish.

During the 1980s, IVF was condemned as immoral by religious groups, but public opinion shifted in favour of these procedures. The next few decades saw rapid development in the field. New drugs, better ovarian stimulation techniques, and improved ways to identify the best embryos, all helped in achieving higher success rates, while costs were lowered. The ability to freeze and subsequently thaw and transfer embryos also greatly improved the feasibility of IVF. By the dawn of the 21st century, it had become a mainstream medical technology. Half a million test tube babies had been born around the world by 2004 and this number increased ten-fold to reach five million by 2012.

Other developments in reproductive medicine included the first baby born to a mother with a womb transplant, reported in 2014.* Three-parent babies became possible in 2016. An even more ambitious and challenging goal lay ahead. It was almost a century since Haldane coined the term "ectogenesis" and replacing traditional pregnancies with fully artificial wombs had now become a real possibility. A number of hurdles remained – including ethical and legal considerations – but genuine progress was being made. One study introduced a mouse embryo into a lab-created uterine lining, resulting in successful implantation and growth on these engineered tissues – held on a bio-engineered, extra-uterine "scaffold." In another study, goat foetuses survived for ten days in a prototype artificial womb consisting of a machine with amniotic fluid in tanks. A third study achieved this with a human embryo, but regulations allowed only a 14-day timespan on research of this kind. These and other breakthroughs led to the first complete working animal wombs in the early 2020s.*

A further decade of pioneering work, alongside a relaxing of regulations, led to a human version in the early 2030s.** This first model demonstrated an ability to supply both oxygen and nutrients from an external source to nurture a foetus, as well as dispose of waste material. The feed incorporated an interface to function as a placenta. During clinical trials, it was made available to a small number of parents, but quickly became widespread in the decade after its introduction.*

With mainstream use having been achieved, rapid changes began to occur in society. Ectogenesis offered a new way of producing children without having to endure a lengthy, painful and potentially dangerous pregnancy cycle. Women no longer had the sole responsibility of childbirth and were free from worries about whether a certain lifestyle or environment (such as alcohol consumption) was harming the foetuses' development. Every aspect of the nine-month process could be monitored in perfect detail by the machines – ensuring a safe and efficient alternative to natural birth. For many women, their lifestyle and career prospects were transformed; a boon for gender equality. Those with damaged, diseased or removed uteri could also take advantage of the procedure. Homosexual couples and single men could also have children without having to use surrogate mothers. Yet another option now available was for pregnant women seeking an abortion to place their embryo in these artificial wombs, allowing somebody else to adopt it rather than killing off the foetus.

Many conservatives and religious groups remained opposed to this process, just as they had been for IVF – but the influence of religion was declining as the world continued to become more secular. Feminists were divided over this new definition of "motherhood" and its effect on their role in society. Meanwhile some expressed concerns that children born in this way could lack an essential bond with their mothers that other children had. However, these machines were able to use vocal recordings, movement, and other sensations to accurately simulate a natural gestation. Even greater advances would emerge in the 2050s with extensive manipulation of DNA in these wombs allowing "designer babies" for the rich.*

Ectogenesis: artificial womb technology | © Sebastian Kaulitzki | Dreamstime.com

2034

Global warming hits 1.5°C

A temporary breach of the 1.5°C limit agreed at the Paris Climate Accords had already been observed during a recent El Niño. This phenomenon is part of a natural heating cycle that occurs every four to seven years in the Pacific Ocean, resulting in particularly hot years. By 2034, the global average temperature is regularly exceeding this threshold,*** with no sign of the increase slowing.

Panic is now setting in, as the impacts of climate change become ever more obvious – with increasingly frequent, record-breaking disasters throughout much of the world, accompanied by disrupted supply chains, falling crop yields, and surging numbers of displaced refugees. With its goal of 1.5°C now largely abandoned, the international community is focused on adaptation efforts and limiting the rise as much as possible.

In the mid-2030s, greenhouse gas emissions are finally peaking. Most developed nations are in the final stages of a transition to renewable sources of electricity. The US, for example, has cut its overall emissions by nearly 50% relative to 2005.* This is slower than required by the Paris Climate Agreement but significantly more than had been expected by some earlier forecasts, due to a landmark bill passed in 2022. Meanwhile, the UK recently achieved a goal of producing 100% of its electricity without fossil fuels and, led by Prime Minister Keir Starmer, established a new publicly owned clean energy company, Great British Energy.*

Even China – the world's largest emitter since 2006 – has now peaked its emissions and begun the long journey towards carbon neutrality, a goal it will reach within the next 30 years. India is close behind, on its way to net zero by 2070.

Significant advances have been made in cutting worldwide emissions of methane, a greenhouse gas with up to 96 times the warming potential of carbon dioxide when measured on a per-molecule basis over a 20-year timescale. At the COP26 summit in 2021, more than 100 nations agreed a 30% reduction in methane emissions by 2030. While this pledge fell short of its target, enough progress occurred to achieve a peak and decline, which has continued with another four years of reductions.

Despite these recent developments, greenhouse gas emissions remain dangerously high, with climate impacts accelerating. Just a decade and a half remains until the middle of the century and a potential breach of the 2°C threshold.

By 2034, the annual chance of a European summer like the 2003 heatwave has reached 30-50%. Warm spell durations in Northern Europe and the Mediterranean have increased by 14 and 15 days, respectively. Annual water availability in the Mediterranean has declined by 9%, while the area burned by summer wildfires has increased by more than 40%.*

In the Americas, temperature increases already exceed the 1.5°C global average – ranging from 1.8°C in the south and southwestern United States to as high as 2.4°C in the northeastern states.* As a result, US crops are being negatively affected, with maize yields now typically at least 10% below where they should be. Other impacts include the Mississippi River now experiencing an 18% increase in the frequency of extreme high flows. The length of the tropical rain season has declined by three days in Central America and as much as ten days in northern Brazil. In Amazonia, warm spell durations have increased by 28 days and the frequency of warm extremes over land has soared by more than 250%.

In Africa, the picture is more mixed. For example, while some regions have seen little or no change in rainfall, others such as the Greater Horn of Africa are experiencing as much as 17% more rainfall. The frequency of extreme high river flows has increased by 9% in the Nile and 25% in the Congo.* The number of people exposed to water scarcity has remained stable in the Sahara region, declined by 13 million in West Africa, and increased by five to six million in the eastern and southern parts of the continent.

In Asia, glacier masses in high mountains are on average 36% lower.* This has been accompanied by an increase in landslides, erosion, and floods, now a common feature in news reports, due to their devastating impact on populated areas below. By mid-century, glacier volumes in the Everest region will have declined by half (relative to 2015),* with serious consequences for water availability. The frequency of warm extremes over land has increased substantially throughout much of the continent – from 76% in Northern Asia to as much as 235% in Western Asia. However, the Russian Federation has benefited from a decrease of one month in average drought length. In terms of populations exposed to river flooding, the worst increases are being experienced by the countries of India (326%), Bhutan (261%), and Bangladesh (227%). For China, the figure is 93%. Despite increasingly disruptive climate events, Asia's crop yields have remained relatively stable, for now, although this will change with 2°C of global warming.

By the mid-2030s, the Arctic Ocean is becoming almost entirely ice-free during summer months.* The resulting change of albedo – from reflective white to a darker and more heat-absorbing surface – is creating feedback loops of amplified warming. The jet stream is also being altered, changing the movement of weather patterns over North America, Europe, and Russia. In a somewhat counterintuitive trend, cold winter extremes in some parts of the northern hemisphere are becoming more likely and winter storms are being driven further south. This is caused by the increasing moisture capacity of the atmosphere, with about 7% more water vapour carried per 1°C of temperature rise. The shifting jet stream is also influencing the path of hurricanes and worsening their damage.

In addition to these immediate short-term impacts, the breaching of 1.5°C has set in motion a number of longer-term trends.* This includes the almost total loss of the Great Barrier Reef by 2050, and a vast thawing of boreal permafrost. The loss of both the Greenland and West Antarctic ice sheets (together accounting for a combined 9 metres of sea level rise in the coming centuries) is no longer a mere possibility, but now likely.*

A growing sense of doom pervades the world, as nations scramble to protect their own interests amid the deteriorating geopolitical situation. Wars are being fought over water, land, and other resources. Borders are becoming tighter. Financial markets are increasingly volatile, in anticipation of a massive collapse in fossil fuel demand. The tourism industry is declining in many regions, due to environmental impacts. Mental health is suffering, with depression the number one global disease burden.* People are becoming reluctant to have children, or even to work and forge careers, as they foresee a bleak future. The sheer uncertainty is a defining feature of this time. The level of political and economic uncertainty in the world had been increasing since the financial crash of 2008 and this trend has continued.*

Service robots number a billion worldwide

By the mid-2030s, the number of service robots has reached one billion worldwide and continues to grow rapidly.* Service robots are generally divided into two separate groups: personal and professional. The former are used in non-commercial settings and usually by laypersons. Examples would include domestic units such as vacuum cleaners, lawn mowers, kitchen chefs, personal mobility assistants, toys and pet exercise robots. The latter group, professional service robots, tend to be used for commercial tasks and are normally operated or monitored by properly trained personnel. Examples can include medical robots performing surgical operations, fire-fighting robots, automated security patrols, machines to clean public places, delivery robots and others designed to assist with retail or leisure environments.

Both personal and professional service robots are separated from another category of machines: industrial robots. This third group is nowhere near as numerous or visible in everyday life, though still growing at a rapid rate during this time.*

The disruption caused by AI, automation and robotisation has accelerated in recent years,* creating a backlash among the general public. Some of the countries most affected include Germany, Italy, Japan, South Korea and Switzerland, where one-quarter of traditional work activities have been displaced.* While some employees are able to transfer into other industries, substantial numbers are unable to do so. This is leading to calls for increased support and intervention by both governments and businesses, such as providing retraining and education for those affected. More radical initiatives, such as universal basic incomes (UBI), have also seen increased public support, with an ever-growing number of countries and regions willing to experiment with the idea.

One of the sectors under most pressure in 2034 is retail, with machines having recently surpassed humans in the majority of tasks.* Shop robots are now a common sight in large grocery, hardware and other stores, where they roam the aisles and restock or rearrange items, perform security functions and handle tasks such as cleaning floors. Unlike the "dumb" machines of earlier generations, robots of the 2030s are considerably smarter – highly adaptable to their surroundings and work situations, able to instantly recognise and interact with countless objects, while providing real-time information to customers. This has come about through exponential improvements in machine learning, cloud computing, bandwidth, sensor technology and so on.

The increasingly sparse numbers of human staff – especially when combined with cashierless payment systems* – can be a rather dehumanising and impersonal experience compared to traditional stores of the past. Senior citizens find it hard to accept the changes.* However, the drive towards ever greater efficiency and productivity has made this trend unstoppable, with more and more businesses employing the use of robots. In some nations, such as Japan, China, South Korea and Taiwan, they are becoming a vital necessity due to aging populations and shrinking workforces.*

Image credits: Domino's Pizza / Kniff Projektagentur GbR / Fraunhofer IPA

NASA's Dragonfly spacecraft lands on Titan

Dragonfly is the fourth mission in NASA's New Frontiers program, chosen by the agency in June 2019. Launched to Saturn in 2026, it arrives on the surface of its large moon Titan in 2034.

The probe, weighing approximately 450 kg (990 lb), lands by parachute in the equatorial "Shangri-La" dune fields, which are terrestrially similar to the linear dunes in Namibia in southern Africa and offer a diverse sampling location. NASA's mission planners analyse many years of earlier Cassini data to choose a calm weather period, along with a safe initial landing site and scientifically interesting targets.

Dragonfly consists of a rotorcraft lander, much like a large quadcopter with double rotors – an octocopter. Its redundant configuration enables it to tolerate the loss of at least one rotor or motor. The craft performs vertical takeoffs and landings (VTOL) and controlled flights between locations, powered by a radioisotope thermoelectric generator (RTG). It can travel at 36 km/h (22 mph) or about 10 m/s and rise to an altitude of 4 km (2.5 miles). The craft is designed to operate at temperatures averaging −179.2 °C (−290.5 °F).

Taking advantage of Titan's dense atmosphere and low gravity (requiring 38 times less power than Earth-based flight), Dragonfly explores dozens of locations across the icy world, covering a total of 175 km (109 miles) over a three-year period. It samples and measures the compositions of its organic surface materials to characterise the habitability of Titan's environment and investigate the progression of prebiotic chemistry. The primary mission target is the huge Selk crater, produced by an impact large enough to have melted Titan's water-ice crust and liberate oxygen in the distant past.

The craft remains on the ground during Titan's nights, which last 192 hours, or eight Earth days. Activities during the night include seismological studies and meteorological monitoring, sample analysis and local microscopic imaging using LED illuminators. It communicates directly to Earth – more than a billion kilometres away – using a high-gain antenna, with a transmission delay of 79 minutes. In addition to spectrometers, meteorological sensors and a seismometer, the scientific payload includes high-resolution panoramic cameras to image Titan's terrain and scout for scientifically interesting landing sites.

The Laser Interferometer Space Antenna (LISA) is launched

The Laser Interferometer Space Antenna (LISA) is a gravitational wave observatory launched by the European Space Agency.** This project is the third of three L-class (Large) missions in the "Cosmic Vision" programme which includes two other spacecraft – the Jupiter Icy Moon Explorer (JUICE) launched in 2022* and the Advanced Telescope for High ENergy Astrophysics (ATHENA) deployed in 2028.*

LISA is designed to sense gravitational waves – tiny ripples in the fabric of space-time – with extreme precision. Three spacecraft are placed in a triangular formation with 2.5 million kilometre sides, flying along an Earth-like heliocentric orbit. Laser interferometry is used to monitor fluctuations in the relative distances between them, with a resolution of just 20 picometres (20 trillionths of a metre, or smaller than a helium atom).*

To eliminate non-gravitational forces such as light pressure and solar wind on the test masses, each spacecraft is constructed as a zero-drag satellite and effectively "floats" around the masses, using capacitive sensing to determine their relative position, with ultra-precise thrusters to remain properly centred at all times.

Previous searches for gravitational waves in space were conducted for short periods by planetary missions with other primary objectives (such as Cassini–Huygens), using microwave Doppler tracking to monitor fluctuations in the Earth-spacecraft distance. By contrast, LISA is a dedicated mission using laser interferometry to achieve a much higher sensitivity. Other antennas had been operational on Earth, but their sensitivity at low frequencies was limited by the largest practical arm lengths, seismic noise, and interference from nearby moving masses.

Passing gravitational waves alternately squeeze and stretch objects by a tiny amount. These waves are caused by energetic events in the Universe, such as massive black holes merging at the centre of galaxies; black holes consuming small compact objects like neutron stars and white dwarfs; supernova star explosions; remnants from the very early phase of the Big Bang and possibly theoretical objects like cosmic strings and domain boundaries.

Since LISA is the first dedicated, space-based gravitational wave detector, the mission adds a whole new sense to our perception of the Universe – enabling astronomers to "hear" events in ways not possible before and revealing many important phenomena that were previously invisible.

EnVision makes orbital insertion at Venus

EnVision is a spacecraft developed by the European Space Agency (ESA) to study Venus. ESA selected EnVision in 2021 as the fifth Medium-class mission for its Cosmic Vision plan. Launched in 2031, it takes 15 months to reach the planet and a further 16 months to achieve orbit circularisation via aerobraking.*

The probe is designed to help scientists understand the relationships between Venus' geological activity and the atmosphere, potentially finding clues as to why Venus and Earth took such different evolutionary paths. It determines the level and nature of current activity, reveals the sequence of geological events that generated its range of surface features and confirms whether Venus once had oceans or was hospitable for life. It provides new knowledge of the organising geodynamic framework that controls the release of internal heat from the planet. The probe's altitude ranges from 220 to 470 km and the mission has a duration of 4.5 years.

Three instruments are included, plus a radio science experiment. The Venus Synthetic Aperture Radar (VenSAR) enables several imaging and ranging techniques at spatial resolutions as fine as 10 metres. It characterises structural and geomorphic evidence of multi-scale processes that shaped the geologic history of Venus and reveals current volcanic, tectonic, and sedimentary activity. A second instrument, the Venus Subsurface Radar Sounder (SRS), penetrates the top kilometre of the subsurface, looking for underground layering and buried boundaries. This includes impact craters and their infilling, tesserae and their edges, lava flows and their edges, plains, and tectonic features, in order to uncover stratigraphic relationships at various depth ranges and horizontal scales. The third instrument, Venus Spectroscopy Suite (VenSpec), provides compositional data on rock types, extremely high-resolution atmospheric measurements, detailed monitoring of sulphurous gases, and scanning of the mysterious UV absorber in the Venusian upper clouds.

In addition to its three main instruments, a gravity and radio system maps Venus' gravity field in high resolution, allowing its deep internal structure to be probed and confirming the size and current state of the core. It also measures atmospheric properties through radio occultation.

EnVision is the latest in a series of probes to study Venus in recent years – the others being Russia's Venera D surface lander, as well as NASA's VERITAS and DAVINCI+ missions – greatly improving the scientific knowledge of this planet.

Australia has fully decarbonised its electricity supply

By 2034, virtually all of Australia's electricity is supplied from renewable energy sources, such as solar, wind, biomass and hydro-power.* For many years, Australia had struggled to break its addiction to fossil fuels. The coal industry, in particular, held enormous sway over the political system. PM Tony Abbott, describing coal as "good for humanity", insisted it would be the "world's main energy source for decades to come." He was followed by Malcolm Turnbull who, although promising to take climate change seriously, did little to alter the status quo. Turnbull was succeeded in 2018 by Scott Morrison, a fanatical lover of coal, who had once mocked the opposition by bringing a lump of coal into the debating chamber.*

Coal production in Australia increased substantially at the dawn of the 21st century – growing by 80% between 2000 and 2015. Australia was the biggest net exporter of coal in the mid-2010s, accounting for 32% of global exports (389 Mt out of 1,213 Mt total) and employing 50,000 people. The enormous Carmichael coal mine was proposed in the northeast of the country, a megaproject that was expected to produce 2.3 billion tonnes of coal over 60 years. This drew immense controversy about its claimed economic benefits, financial viability, plans for government subsidy and damaging environmental impacts. Alongside its potential harm to the nearby Great Barrier Reef (through dumping of dredge spoil), concerns were raised about groundwater pollution and the clearance of threatened species at the site, including koalas. Furthermore, the vast amount of carbon emissions, from this single mine alone, would be around 0.5% of the worldwide carbon budget limit for avoiding 2°C of warming. Nevertheless, the project continued to move forward, receiving billions of dollars in government assistance.

Carmichael was just the first of a number of large mines proposed for the Galilee Basin and was intended to facilitate their development too. Australia had experienced record growth in coal exports, with its largest importers being Japan (34%), China (24%), South Korea (15%) and India (14%). Much of the remaining glut of coal was consumed domestically, accounting for nearly 50% of Australia's electricity supply in 2015. The country was among the highest of the developed nations in terms of carbon footprint per capita.

However, the world was changing fast; in particular, with regards to energy production. Australia was not immune to the revolution now underway and faced losing billions of dollars in stranded assets. Early warning signs had provided a glimpse of what was to come – such as the auctions held in India, during which solar-generated electricity became cheaper than coal.* This had followed earlier reports that international coal projects relying on new import markets faced major financial risks.* Even when the costs of storage (to make intermittent power sources reliable) were added, renewable energy was becoming Australia's cheapest energy option.*

These changes had become more and more obvious in the late 2010s and continued into the 2020s. Between 2018 and 2019 the nation installed over 10,400MW of new renewable energy, helped by Australia's superb geographical placement and high level of solar irradiance. The accelerating trends in solar and wind power were accompanied by a corresponding decline in coal production, as mines and power stations proved to be economically unviable, either shutting down or being mothballed indefinitely. Renewables were even beginning to match the wholesale price of gas in Australia, meaning that solar-generated electricity could directly compete for provision of industrial heat.

By 2025, renewables had overtaken fossil fuels when measured by terawatt-hours (TWh) and were supplying 50% of Australia's electricity. The large-scale exposure of investors to stranded assets was producing a "carbon bubble" with major economic repercussions – particularly for Australia, but also many other countries around the world. As the plunging value of fossil fuels became apparent, the bursting of this bubble created one of the largest economic crises of the first half of the 21st century.* This setback was only temporary, however, as the world transitioned to a clean energy future. By 2034, renewables are supplying essentially all of Australia's electricity.*

Switzerland phases out nuclear energy

After the Fukushima disaster in Japan, questions were raised about the long-term viability of nuclear power. Switzerland was among the nations to abandon this form of energy production, following public protests and a government review. The country’s five existing reactors – supplying about 40% of the country's power – were allowed to continue operating, but were not replaced at the end of their life span. The last plant is taken offline in 2034.*

A nuclear power station with a cooling tower in Leibstadt, Switzerland.

Caribbean coral reefs are in danger of being wiped out

Often called "rainforests of the sea", coral reefs form some of the most diverse ecosystems on Earth. Historically, they have occupied less than 0.1% of the world's ocean surface – about half the area of France – yet provided a home for 25% of all marine species. Delivering a range of ecosystem services to tourism, fisheries and shoreline protection, the global economic value of coral reefs at one time was estimated at up to $375 billion each year.*

However, coral reefs are fragile ecosystems, partly because they are so sensitive to water temperature. In the early 21st century, they were under threat from climate change, oceanic acidification, blast fishing, cyanide fishing for aquarium fish, sunscreen use, overuse of reef resources, and harmful land-use practices; including urban and agricultural runoff and water pollution, harming reefs by encouraging excess algal growth.

The Caribbean – home to 9% of the world’s coral – saw a 50% decline between 1970 and 2012, leaving just one-sixth of the pre-industrial reef cover. According to a detailed analysis in 2014, virtually all of the remaining Caribbean coral reefs would disappear within 20 years, based on current trends.* Climate change had once been seen as the main culprit, lowering the pH level and causing bleaching. While ocean acidification was still a serious threat, new data suggested that a loss of parrotfish and sea urchin – the area’s two main grazers – was, in fact, the biggest driver of coral decline in this particular region.

For example, an order-of-magnitude increase in bulk shipping during the 1960s-70s introduced pathogens and invasive species near the Panama Canal that later spread to the Caribbean. An unidentified disease led to a mass mortality of the sea urchin in the 1980s, while extreme overfishing brought parrotfish to the brink of extinction in some regions. Loss of these species broke the delicate balance of coral ecosystems and enabled algae – on which they fed – to smother the reefs. Areas protected from overfishing, as well as other threats such as pollution, tourist activity and coastal development, were more resilient to pressures from climate change.

Some of the healthiest coral reefs, with high populations of grazing parrotfish, included the Flower Garden Banks National Marine Sanctuary in the northern Gulf of Mexico, Bermuda and Bonaire, all of which banned or restricted fishing practices that harmed the fish. Reefs where the parrotfish were not protected suffered tragic declines – such as Jamaica, the entire Florida Reef Tract from Miami to Key West, and the U.S. Virgin Islands.

Attempts were made in subsequent decades to protect these species across a wider area, and restore the balance between algae and coral using better management strategies. Although some of these efforts achieved modest success, short-term economic pressures and business interests tended to outweigh these concerns. The region as a whole remained under serious threat, and by 2034, Caribbean coral reefs have edged further towards complete collapse.*

Coral reef dead zones in the Caribbean. Credit: Catlin Seaview Survey

Coastal erosion has destroyed hundreds of UK homes

Rising sea levels and increased storm intensity have begun to seriously affect the British coastline. By the mid-2030s, more than 800 homes have been lost due to erosion. While mitigation efforts have been stepped up around the country as a whole, these particular homes were deemed too expensive to save, resulting in their occupants being forced to abandon them and settle elsewhere, with little or no government compensation. During especially stormy years, up to 7 metres (23 ft) of land is being eaten away per year in some places* – the highest rate in Europe. The most at-risk areas include Devon, Cornwall, the Isle of Wight, Yorkshire and East Anglia. As well as buildings, the shrinking coastline has affected farmland, nature reserves and nuclear power plants, along with a nationwide public footway established in the previous decade.* Towards the end of this century, the number of homes being lost will increase more than eight-fold to 7,000. If no action were taken, the figure would grow 90 times higher, from 800 to 74,000.*

A major supermoon occurs

A so-called "supermoon" occurs when a full moon coincides with a lunar perigee – the closest approach of the Moon in its elliptical orbit around Earth. Such events produce the largest apparent size of the lunar disk as seen from Earth, making it appear 15% larger and 30% brighter than during apogee (its most distant point from Earth). This provides great opportunities for astronomers and photographers. Particularly dramatic supermoons occur when a full moon and lunar perigee also happen when Earth is at perihelion (its closest point to the Sun for the year).

On the morning of 14th November 2016, the distance between the centre of the Moon and Earth was 221,524 miles (356,509 km), the closest they had been together during a full moon since 1948. The Moon would not appear this large again until 25th November 2034. The closest supermoon of the century occurs on 6th December 2052. Notable supermoons are also observed in 2070, 2088 and 2098.*

 By FutureTimeLines