The Bering Land Bridge, or Beringia, was a massive landmass that once connected Asia and North America during the Ice Age. Spanning up to 1,000 miles from north to south and 600 miles wide at its peak, this expansive region served as a vital corridor for the migration of humans and animals. It played a crucial role in shaping the movement of species and the course of human history. Genetic studies reveal that individuals across Canada, North America and South America share direct ancestral links with populations in present-day Eastern Russia, highlighting the impact of this ancient land bridge.
The Bering Land Bridge emerged as a result of dramatic climatic and geological changes during the Ice Age, particularly in the Pleistocene Epoch. During this time, glaciers trapped vast amounts of the Earth’s water, causing sea levels to drop by as much as 400 feet, which exposed the Bering Land Bridge. This vast landmass supported diverse plant and animal life, creating a rich ecosystem that provided essential resources for migrating species. Over millennia, the bridge was repeatedly exposed and submerged due to the cyclical nature of glaciations and interglacial periods.
Archaeological and genetic evidence suggests that the first humans to cross the Bering Land Bridge were small groups of hunter-gatherers in search of animal food sources and more favourable climates. According to the “Beringian Standstill Hypothesis,” these early migrants are believed to have spent thousands of years living on the bridge itself, adapting to its unique environment. Once ice-free corridors opened up, these populations moved southward, eventually spreading throughout the Americas.
The Bering Land Bridge served as a critical corridor for the exchange of plant and animal species between continents during the Ice Age. North American species such as horses and camels migrated into Asia, while Asian species like mammoths and saber-toothed tigers journeyed into North America. This bidirectional movement enriched biodiversity on both continents and played a pivotal role in shaping evolutionary pathways.
The disappearance of the Bering Land Bridge around 11,000 years ago led to the isolation of plant and animal populations, driving distinct evolutionary pathways. The earlier exchange of species had enriched the genetic pool and fostered ecological resilience on both continents, highlighting the transformative impact of such connections. The impact of the Bering Land Bridge serves as a reminder of the pivotal role geographical features play in shaping biodiversity. Even today, the shared ancestry of certain plants and animals in Asia and North America stands as evidence of these ancient migrations.
The next time you look at a world map, ask yourself, “Is this world map wrong?”. Maps are everywhere, hanging in classrooms or your home study wall and appearing on websites. But have you ever wondered if the world map you know is actually accurate?
World maps are complex representations of the Earth’s surface that involve significant compromises and distortions. The challenge arises because the Earth is a three-dimensional sphere, but maps are flat, two-dimensional representations. When translating the Earth’s curved surface onto a flat map, cartographers must decide what to keep accurate and what to distort. This has led to the creation of various map projections, each with its own strengths and weaknesses.
While it’s unlikely you use these maps in an educational environment, the Babylonians (600 BCE), Greeks (6th century BCE), and the Byzantine monk Ptolemy, (2nd century CE), used travelers’ accounts and mathematical calculations to depict the world’s basic layout, often featuring one to three continents. With more data and exploration, they could have created even more accurate maps.
However, the typical classroom map you see is likely based on the more (relatively speaking) recent Mercator projection, developed in the 16th century, informed by both historical and new knowledge from global exploration. The creation of accurate maps remained challenging, however, because full geographic information was still limited; as such, maps were built painstakingly from the notes, accounts, and observations of these explorers. Despite these limitations, the Mercator projection was revolutionary for its time because it preserved angles and directions, making it useful for navigation. However, the first Mercator maps also distorted the true sizes of continents and oceans, especially those farther from the equator.
Some notable distortions in the Mercator projection included:
Greenland, Siberia, Canada, and Antarctica appear disproportionately massive.
Greenland alone looked roughly the size of Africa, even though Africa is actually 14 times larger.
Africa appears smaller than North America, although it is, again, larger.
In contrast, the Gall-Peters projection, developed in the 19th century, was designed to preserve the relative area of land masses, offering a more accurate sense of the size of different countries. Although this projection distorts the shapes of continents, making them appear stretched or squashed, their relative sizes are more accurate, with Africa shown as larger than North America and Europe. This projection sparked political controversy, which may have limited its popularity. Other projections have since been developed to balance distortions in size, shape, and distance, but the Mercator and Gall-Peters projections remain among the best-known.
Thanks to satellite imagery and advanced technology, such as Google Maps, we now have the capability to create accurate global images. While the physical challenge of gathering geographical data has been largely overcome, today’s challenge lies in creating map projections that are politically acceptable in a complex geopolitical landscape. So, if you’re looking for a truly accurate and politically neutral view of the world, the best option may still be a globe!
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October half-term is the perfect time to take a break from the hustle of daily routines, enjoy autumn’s beauty, and spend quality time with family and friends. With Halloween festivities and the crisp, colourful weather, this is a great opportunity to embrace the season’s charm while keeping kids entertained. Whether you’re looking for outdoor adventures, cultural experiences, or creative indoor activities, here are some fantastic ideas to make the most of the October half-term.
Visiting a pumpkin patch is a quintessential autumn activity that kids and adults alike will enjoy. Many farms across the UK open their fields for pumpkin picking in October, offering a fun day out where you can choose the perfect pumpkin to carve for Halloween. Many pumpkin patches also host other activities, such as tractor rides, corn mazes, and petting zoos. Don’t forget to snap a few seasonal photos to capture the magic of autumn!
Top Tip: Check local farms for pre-booking requirements, as pumpkin patches can get busy during the half-term.
With the leaves turning golden and the crisp air setting in, October is one of the best months for enjoying the UK’s stunning natural landscapes. Take a trip to a nearby national park or woodland for a peaceful family hike, picnic, or wildlife spotting. Autumn is the perfect time for collecting conkers, pine cones, and colourful leaves to use in seasonal crafts later.
Where to go: The New Forest, Peak District, or Sherwood Forest are all fantastic for autumn walks.
Many attractions across the UK embrace the spooky spirit of Halloween with special events that range from family-friendly fun to haunted house experiences for older kids and teens. From ghost tours and haunted castles to pumpkin trails and fancy dress parties, there’s no shortage of ways to get into the Halloween spirit.
Where to find Halloween events: Check your local museums, stately homes, and theme parks for Halloween activities. Some, like Warwick Castle, have special Halloween experiences with spooky trails and stories.
For families with a love of outdoor sports, half-term is an excellent time to try an adventurous activity. Many outdoor centres offer everything from climbing, abseiling, and archery to paddle boarding and canoeing. Adventure parks and activity centres often run special half-term sessions where kids can learn new skills or try something new in a safe, supervised environment.
Great outdoor activity centres: Go Ape locations across the UK are ideal for tree-top climbing and zip-lining, while centres like PGL or local adventure parks offer multi-activity days.
The UK’s rich history offers a wide range of fascinating historical sites and castles to explore. Many of these places run special half-term activities for families, such as themed treasure hunts, costume days, or living history demonstrations. Visiting a castle or historic house is not only a great way to learn about history but also a chance to explore stunning grounds and gardens.
Top sites to visit: Windsor Castle, Tower of London, and Edinburgh Castle are popular, while lesser-known gems like Bodiam Castle and Kenilworth Castle often host half-term events.
If the weather isn’t on your side, a visit to a museum or science centre can provide an educational and exciting day out. Many museums across the UK offer free entry and have interactive exhibits that are perfect for children. Check if your local museum is offering any half-term workshops, craft activities, or temporary exhibitions that might pique the interest of curious minds.
Family-friendly museums: The Natural History Museum and the Science Museum in London are firm favourites, while the Eden Project in Cornwall and the Museum of Science and Industry in Manchester are excellent alternatives.
For a creative day indoors, why not try some autumn-inspired arts and crafts? Leaf printing, pumpkin carving, and making Halloween decorations are great ways to get into the seasonal spirit. You can collect natural materials like leaves, acorns, and pinecones from a nearby park or forest to use in your projects. Baking Halloween-themed treats like spooky cookies or toffee apples is another way to make the day special.
Craft ideas: Make autumn wreaths, paint pine cones, or create spooky garlands to hang around the house.
Autumn is a wonderful time to see wildlife, as many animals prepare for winter. Whether you visit a wildlife reserve, zoo, or a local nature reserve, half-term is a great chance for kids to learn about nature. Many wildlife centres offer guided walks, bird-watching sessions, or even bat walks, where you can discover nocturnal creatures in a safe environment.
Top wildlife parks: Visit Longleat Safari Park or Woburn Safari Park for an exciting animal adventure, or take a quieter trip to a wildlife reserve like RSPB Minsmere or Slimbridge Wetland Centre.
Many theatres across the country put on special performances for children and families during the October half-term. Whether it’s a magical pantomime, a musical, or a puppet show, catching a live performance is a fantastic way to introduce children to the arts and enjoy a cosy afternoon together. Check your local theatre for family-friendly performances, including adaptations of popular books and films.
Theatres to watch: The West End in London offers big productions, while local theatres often have affordable, charming shows perfect for younger audiences.
Many theme parks across the UK go all out for Halloween, offering special spooky events alongside their usual rides and attractions. Some parks feature haunted mazes, scare zones, and Halloween-themed parades. These parks cater to various age groups, with milder activities for younger children and scarier thrills for teens and adults.
Theme parks to try: Alton Towers, Chessington World of Adventures, and LEGOLAND Windsor offer Halloween events perfect for a family day out.
If you’re looking for a cost-effective activity, why not create your own treasure hunt at home? You can make it Halloween-themed, with clues leading to hidden treats or spooky surprises. Tailor the difficulty to suit the age of your children, and let them solve puzzles or follow maps to find hidden treasures. This can be a brilliant way to engage their imagination and keep them entertained indoors.
For a relaxing day at home, plan a cosy movie marathon. You can theme it around Halloween with spooky-but-not-too-scary films for younger kids or pick a family-favourite series like Harry Potter. Create a cinema experience by making popcorn, dimming the lights, and letting everyone choose their favourite film.
Movie ideas: The Nightmare Before Christmas, Hocus Pocus, or Coco are great autumnal options.
October half-term offers a wonderful opportunity to enjoy the best of autumn, whether that’s embracing the season’s natural beauty, indulging in Halloween festivities, or spending quality time indoors. With a range of activities that cater to every interest and budget, there are plenty of ways to make the most of this break and create lasting memories with your family.
There are many subjects related to activities available for half-term. You can find them at the top of Oxford Open Learning’s Home Page by clicking on ‘Courses’. There are a variety of levels you can choose to study at for most subjects. You can also Contact Us for more information.
Nowadays, it’s easy to take digital maps for granted; we can easily pull out our phones to find directions and get suggested travelling routes. However, many centuries ago, maps did not exist and our perceptions of the world were very different. The art of mapping, or cartography, has revolutionised our understanding of our planet, but even with high precision mapping and digital technology, maps are always being updated. “Sandy Island”, which was known to be in the South Pacific, for example, was included in maps for over 200 years, but in 2012 scientists proved it didn’t exist when the island couldn’t actually be located.
While evidence of the earliest maps created are contested, from mammoth tooth inscriptions to cave art star maps, Babylonian maps created in 600 BC on clay tablets are generally accepted as the first real global scale maps. Early maps such as these were based more on speculation than scientific approach and had no measure of scale, depicting the Earth as a flat disc. The first scientific approach to cartography was made by Greek astronomer and mathematician Claudius Ptolemy in the 2nd century AD. Through his work on horoscopes, Ptolemy devised a system of longitude and latitude to accurately plot global locations and create a two-dimensional map of the world – which was now known to be round.
The 15th and 16th centuries marked a pivotal era in the history of mapping. Explorers such as Christopher Columbus, Vasco da Gama and Ferdinand Magellan, through desire for trade and conquest, discovered new lands such as the Americas and new sea routes. New maps were needed to showcase nautical routes with greater accuracy. Much of the inland of these newly found continents was still speculated at the time, however (See the largely absent North America on the map above, which was drawn up around 1621).
The Mercator projection, developed by Gerardus Mercator in 1569, further revolutionised nautical navigation through the ability to represent lines of constant course as straight lines. The mathematical method of the map’s construction caused land masses appear further away from the equator and become distorted and disproportionally larger. This made its practical usage limited but it was ideal for nautical navigation.
During the 17th and 18th centuries, scientific advancements brought about more precise methods for mapping. The invention of the chronometer by John Harrison allowed mariners to finally measure their longitude wherever they were at sea, improving sea navigation. Mapping agencies began to appear along with large scale surveys. In 1745, The Ordinance Survey first started mapping the UK, initially as part of a military defence strategy, bringing with it a higher level of detail than previously seen.
The 20th century has brought with it new technology such as the internet, satellites and geographic information systems (GIS). These advances have allowed the rapid development of highly sophisticated digital maps, through the use of aerial mapping, spatial awareness and data sharing. Companies such as Google have completely revolutionised modern maps, allowing for a higher level of detail and interactivity.
While historically maps have served the purpose of navigation, territory marking, trade routes and military campaigns, modern maps are able to provide high-level advantages. GIS technology has allowed scientists to map the spread of diseases, climate change, migration patterns and land development.
This additional level of spatial data has also allowed informed decisions to be made on resource management and urban development. Businesses can analyse customer location data while emergency responders can use GPS locations to rapidly locate accident scenes. Future developments such in AI and real-time dynamics will continue to make our maps more interactive and integrated into our everyday lives.
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Our oceans are forever in motion, transporting nutrients and thermal energy across the globe. The thermohaline circulation, sometimes called the Ocean Conveyor Belt, is a vast and complex interconnected system that facilitates this motion through differences in water density. The thermohaline circulation helps to maintain a stable climate and plays an important role in the absorption of greenhouse gases from the atmosphere.
While winds effect the upper 100 metres of the oceans surfaces, changes in water density due to salinity (salt concentration) and temperature affect deeper ocean currents. The theory of thermohaline circulation was first proposed by Henry Stommel and Arnold Arons in 1960 and is an extremely slow process – the circulating water moves at approximately 1cm per second and takes 500 years to complete a full cycle.
In warmer climates near the pacific equator, surface water is heated by the sun and flows west through the Indian ocean, southern Africa and up towards the North Atlantic via the Gulf Stream. As the warm water reaches Greenland and Norway, the effects of evaporation, heat loss and the formation of ice increases the level of salination in the water. This increases its density, causing it to sink to the ocean floor as ‘North Atlantic Deep Water’. This effect forces displaced nutrient rich water south towards Antartica and then eastwards as part of the Antartic Circumpolar Current. As it passes back into the Pacific, it starts to mix with warmer water which causes an upwelling, completing the THC cycle.
The thermohaline circulation plays an important role in the stabilisation of the Earth’s temperature by supplying heat from the equator to the polar regions. This helps cool down the hotter regions and regulates the rate of polar sea ice formation. Changes in oceanic temperature influences global weather patterns; the gulf stream for example causes the climate of Western Europe to be milder than other regions of similar latitude.
The thermohaline circulation supports marine life and biodiversity where nutrient-rich deep water upwelling promotes the growth of plankton – the foundation energy source for the oceanic food web. The cycle also helps to lock away greenhouse gases such as carbon dioxide into the depths of the ocean, helping to mitigate the effects of global warming.
There is a growing concern for the health of the thermohaline circulation system. Global warming has led to the warming of the oceans waters and melting of the polar ice caps, the latter leading to a decreased level of salination in the polar regions. These effects make it more difficult for the formation of North Atlantic Deep Water, leading to a slowdown in the thermohaline cycle. Scientist research has suggested that if carbon emission remain constant, the thermohaline circulation will slow down by more than 40% over the next 30 years.
A collapse in this oceanic system will lead to lower levels of marine life, increased weather and global climate instability, changes in sea levels and flooding and depletion of fish stocks. Past disruptions have been attributed to the glacial conditions of the Younger Dryas event, around 12,000 years ago. We must therefore take care to ensure the future of this fragile ecosystem through practices such as sustainability and the reduction of greenhouse gasses.
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The Gulf Stream is a powerful ocean current that originates in the Gulf of Mexico, travels along the eastern coast of the United States, and then crosses the Atlantic Ocean towards Europe. It is part of the larger North Atlantic Gyre, which is a circular system of currents in the North Atlantic Ocean. The stream is also part of another system called the Atlantic Meridional Overturning Circulation, or AMOC. This system brings warm water from tropical areas north on the surface. When it reaches the Arctic it cools down and sinks and travels south along the ocean floor as part of the deep ocean’s circulation.
The warm waters, (and the associated warm air), from the Gulf Stream have a significant role in moderating the UK climate. For example, during the winter months, the Gulf Stream brings warmer air to the region, preventing extreme cold temperatures that would otherwise occur at such high latitudes. The Gulf Stream means that winters in the UK tend to be milder compared to other regions at similar latitudes, such as eastern Canada. This climate chart shows that the average low in the mid-winter months of Dec and Jan is minus 10.5 degrees Celsius, yet in London at corresponding latitudes, the average winter month temperature is minus 1 degrees Celsius. Although a simplistic analysis this relatively warming 10-degree positive swing in winter temperature clearly illustrates the impact of the Gulf Stream on the UK climate which should be like the bitterly cold Canadian climate.
The impact on our summer climate is not as straightforward as daytime temperatures in London and Calgary are similar during the summer months, but overnight temperatures are about 5 degrees lower in Calgary.
The Gulf Stream also plays a role in transporting moisture from the tropics towards Europe. This moisture contributes to rainfall in the UK, particularly in the western and coastal regions. Areas on the western coast, such as Wales and western Scotland, tend to receive more rainfall than eastern regions due in part to the influence of the Gulf Stream.
The Gulf Stream has a significant impact on the climate of the UK, helping to create the relatively mild and temperate conditions that are characteristic of the region, despite its high latitude. However, the latest Scientific research suggests that it is weakening and slowed by 4% over the last 40 years, which will have as yet unquantifiable impacts on the UK climate. This is a hotly contested issue, but one we’ll save that for another article!
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The Severn Bore is a natural phenomenon that occurs on the River Severn in the United Kingdom. It is a tidal bore, which is a large and powerful wave that forms in the river because of the incoming tide from the nearby Atlantic Ocean
Of course, these bores aren’t present or noticeable in every river and there is a reason that the Severn bore exists and is such a spectacle. This is due to it having one of the highest tidal ranges in the world, with the difference between high and low tides often exceeding 14 meters (46 feet). This significant tidal range is a key factor in the formation of the Severn Bore.
As the Atlantic tide pushes water up the narrowing estuary of the River Severn, the water is funnelled into a progressively narrower channel. This narrowing of the estuary helps to amplify the incoming tide and creates the world-famous Severn bore, a powerful wave that travels upstream against the direction of the river flow. The wave can reach heights of up to two meters (6.6 feet) and travel at speeds of up to 21 kilometres per hour.
This would of course be quite a ride for anyone choosing to surf it, which people do! Colonel ‘Mad’ Jack Churchill was the first person documented to have surfed the bore, back in 1955. Surfers, being notorious thrill seekers, tend to target the biggest 3, 4, and 5 star bores, (with 5-star bores happening rarely, perhaps once a year).
The Seven Bore is most pronounced during the spring and autumn months when the tidal range is at its highest. Friday 17th September to Saturday 19th October is the next, most densely packed period of 3- and 4-star bores. The size of the bore is influenced by various factors, including the alignment of the sun and moon, as well as atmospheric conditions, the amount of water flowing down the river and how well sourced the main drainage channels are.
The Seven Bore is a popular attraction for spectators, (underlining its phenomenon status), who gather along the banks of the Severn to watch as it travels upstream. You might even see me there as it’s very local to where I live.
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https://www.geograph.org.uk/photo/1735611
Licence:https://creativecommons.org/licenses/by-sa/2.0/
When you look at the vast, arid landscape of the Sahara desert, you may find it hard to believe that this was once a lush, green space full of grasses, trees and lakes. Yet this is likely the case. It has been called the North African Humid Period, and occurred around 12,000 years ago during the late Pleistocene and Holocene geological epochs.
There is good paleoclimatological evidence to suggest that over the last 3,000,000 years, there have been 230 of these North African Humid Periods (NAHPs), indicating that the Sahara region alternates between arid phases (as present) and humid phases, which are full of rivers, vegetation and lakes. According to an article in Nature Magazine online, these NAHPs are governed by a phenomenon known as the Procession Cycle, which is when a wobble occurs in the orientation of the Earth’s axis of rotation. Thereafter, you might imagine the planet as a slightly off-centre spinning top. This off-centre rotation continues for a period of around 25,000 years. Procession is an additional form of planetary motion to the more well-known daily rotation and annual revolution cycle of the Earth. It is caused by the gravitational tidal force of the Sun and Moon acting on our planet’s equatorial bulge. There is a good visual of this rotational phenomenon here on Wikipedia.
The wobble itself is known as an Axial Procession, and it makes seasonal contrasts more extreme in one hemisphere and less extreme in the other. Not only does the procession cycle govern the seasonal contrasts, it determines temperature and precipitation variance between seasons. During the periods of increased Boreal Summer Insolation (when solar radiation hits the Earth’s northern hemisphere between March and September), the African Monsoon systems are intensified. It is these precipitation-rich phases of the procession cycle that underpin the North African Humid Periods.
This article in the Geographical explains how the most recent incarnation of the dry version of the Sahara came about. Around 12,000 years ago, the end of the ice age led to a wetter climate in the region, possibly due to low-pressure areas forming over collapsing ice-sheets in the north. But, once these ice sheets melted, the Northern Sahara region dried out. However, monsoon conditions in the South meant that the Southern Sahara region was wetter. But, eventually this monsoon retreated south (as part of the procession cycle) and the entire Sahara region become desert. This is the incarnation of the Sahara you see today.
When will this cycle end, then? Well, not for a while. Experts predict that the Sahara will revert back to that lush green alternative state in about 10,000 years.
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Human Biology IGCSE Fast Track
Our planet is a treasure trove of fascinating natural wonders, and when it comes to geographical oddities, few things are as intriguing as islands within lakes within islands. These peculiar formations defy conventional expectations, showcasing the awe-inspiring creativity of nature. Today, we embark on a journey through this quirky world.
One remarkable example of this phenomenon can be found in the heart of Canada’s Manitoulin Island, the largest freshwater island in the world. Within the already impressive Manitoulin Island lies Lake Manitou, a vast inland lake that holds an astonishing secret. Deep within the waters of Lake Manitou are two smaller islands: Treasure Island and Flowerpot Island. These each create a mesmerising and unexpected natural spectacle, demonstrating nature’s ability to surprise and astonish us.
Venturing across the globe, we find another illustration of this phenomenon in the Philippines. In the picturesque Taal Lake, or Taal Volcano Caldera (pictured), rests Volcano Island. This island, shaped like a smaller replica of its titular parent volcano, holds its own miniature crater lake, known as the Main Crater Lake. Intriguingly, it temporarily vanished following the eruption of the Taal volcano in 2020, but as the eruption subsided and very wet weather blew in, it returned. This shows how the interplay of such inter-related geographic features creates truly unique, as well as visually stunning landscapes.
These geographical oddities not only captivate our imagination but also serve as valuable reminders of the dynamic forces that shape our planet. They are windows into the geological history of an area, revealing a complex interplay of volcanic activity, erosion, and tectonic forces. By studying these formations, scientists gain insights into the intricate processes that have shaped our world over millions of years. We are reminded that the natural world is full of surprises waiting to be discovered, with peculiar, fascinating formations highlighting the delicate balance of Earth’s ecosystems. Each layer of island on lake on island supports a unique array of flora and fauna adapting to the specific conditions within their microcosmic environments, and it’s essential to cherish and such natural wonders. They represent the beauty and resilience of our planet and remind us it is our responsibility to be stewards of the environment. By preserving these unique formations’ environmental qualities we can ensure that future generations will also have the opportunity to witness and appreciate them.
The start of this month saw the marking of World Tsunami Awareness Day. Following up on this subject, let’s explore what a tsunami actually is and discover the stories of some of the most devastating in history.
The word ‘tsunami’ is Japanese, meaning ‘harbour wave’. Tsunamis are essentially large waves caused by oceanic earthquakes or volcanoes. When an earthquake occurs, or there is a volcanic eruption deep under the ocean, the water around it is displaced and often forms a large wave. As the wave moves closer and closer to land it grows taller as the ocean shallows close to shore (as shown in the visual above.) Not all earthquakes and volcanoes will cause a tsunami but one way to predict them is if the water at the shore begins to quickly recede after an earthquake. Tsunamis can be hundreds of feet tall and travel extremely quickly, so they can be incredibly destructive for the areas affected by them. Below are a couple of examples of some of the worst to have been recorded.
One of the deadliest tsunamis ever occurred off the coast of Sumatra on the 26th December 2004. A magnitude 9.1 earthquake created a wave that towered 50m tall and reached 5km inland. It is estimated to have cost around US$10 billion of damage and killed around 230,000 people.
Another of the more recent tsunamis to have caused a great deal of devastation struck the coast of Japan on the 11th of March 2011, having begun with a 9.0 magnitude earthquake. With waves 10m high and arriving at an especially rapid speed of 800km per hour, this tsunami killed more than 18,000 people and displaced around 452,000 whose homes had been destroyed. As well as generating the tsunami, this earthquake caused a nuclear emergency at the nearby Fukushima Daiichi power plant, which began to leak dangerous radioactive steam. The damage that this natural disaster caused is estimated to have been in the region of $235 billion.
As mentioned, tsunamis are not only caused by earthquakes. The Krakatau, or Krakatoa, volcano is located on a small Indonesian island in the Sundra Strait between the larger ones of Java and Sumatra. When it erupted on the 27th of August 1883, it caused waves as high as 37m to form. This tsunami destroyed the towns of Merak and Anjer on Java, and its effects were felt as far away as India and Sri Lanka too. The event killed around 40,000 people in total, though many of those deaths were directly caused by the volcano, rather than the tsunami.
Tsunamis don’t just occur in East and South-East Asia. On the 1st of November 1755, three waves struck the west coast of Portugal and southern Spain. These tsunamis, which reached up to 30m high, together with the earthquake that caused them, killed around 60,000 people in Portugal, Spain and Morocco.
For more information about tsunamis, and of the most powerful in history, visit What Is a Tsunami? at NASA’s Space Place website – and The 10 Most Destructive Tsunamis In History at australiangeographic.com.