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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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.
The polar regions, Arctic and Antarctic, represent some of the most extreme and unforgiving environments on Earth. Yet, they have long captivated the human imagination, drawing explorers and adventurers in search of discovery, with their allure of the unknown. Their icy landscapes, at the ends of the Earth, have stories to tell — tales of heroism, survival, and environmental change.
Exploration of the polar regions dates back centuries, throughout which some of the most celebrated names of discovery have left an indelible mark on these harsh, remote landscapes. Men like Robert Peary and Frederick Cook vied for the title of “first to reach the [North] pole,” with the former claiming success in 1909… (Whilst Peary was attributed for being first for a long time, in more recent years Cook‘s claim to have done so in 1908 has come in for greater consideration…). In either case, it was a feat that would test human endurance and navigation skills to their limits.
In the South, the Antarctic was the stage for iconic figures like Ernest Shackleton, Robert Falcon Scott, and Roald Amundsen, who each led brave expeditions to reach the elusive South Pole. These expeditions faced even more extreme cold, greater isolation, and the same ever-present threat of frostbite and death. It was Amundsen who first attained this goal.
The legacy of these early explorations is not just tales of human perseverance, but also one of science. Polar exploration has contributed significantly to our understanding of the Earth’s climate, geology, and ecosystems. These regions have unique biodiversity, being home to species who have adapted to extreme cold, such as penguins, seals, and polar bears.
However, as the world grapples with climate change, the polar regions have become barometers of its severity, in speed and extent. The rapid warming of the poles, with melting ice and the resulting changes to its ecosystem, serves as a stark reminder of the impact of human activities on our planet.
The story of the polar regions is not one of static, frozen wastelands but a dynamic and evolving narrative. Climate change has profound consequences for the polar ecosystems, affecting not only the iconic creatures that call these regions home but also the indigenous communities that have adapted to life in these extreme environments for generations. In the face of these environmental challenges, contemporary explorers and scientists continue to brave the cold to document the changes taking place. They conduct vital research on ice dynamics, sea-level rise, and the impact of melting ice on the global climate. Their work not only advances our understanding of the Earth but also underscores the urgency of addressing climate change.
The changes taking place in the Arctic and Antarctic are not isolated events but part of a larger story of environmental change, one that requires global cooperation and an unwavering commitment to protecting the Earth’s delicate polar ecosystems.
The field of archaeology holds a fascination for uncovering the mysteries of ancient civilisations and lost worlds. Traditionally, archaeologists rely on painstaking excavation, analysis of artefacts, and interpretation of historical records to piece together the past. However, a new tool has emerged that is revolutionising the field: generative artificial intelligence (AI). By harnessing the power of AI-powered simulations, archaeologists can now reconstruct and visualise these lost worlds in ways previously unimaginable.
Generative AI refers to the use of machine learning algorithms to create new content based on patterns and data it has been trained on. In the context of archaeology, generative AI can analyse existing archaeological data, such as artefacts, ruins, and landscapes, and generate realistic simulations of what these ancient sites might have looked like in their prime.
One application of generative AI in archaeology is the reconstruction of ancient cities and buildings. By feeding the AI with data from excavated remains, historical texts, and artistic depictions, it can generate 3-D models and visualisations of the structures as they would have appeared centuries or even millennia ago. This technology allows archaeologists and historians to digitally step back in time, exploring the architecture, urban planning, and daily life of ancient civilisations.
Generative AI simulations also aid in understanding ancient landscapes and environments. By analysing geological data, climate records, and flora and fauna distribution, AI algorithms can recreate past ecosystems and landscapes. This enables researchers to study how ancient peoples interacted with and adapted to their surroundings, shedding light on topics like agricultural practices, resource management, and the impact of climate change on past civilisations.
Moreover, generative AI can help fill in the gaps left by incomplete or damaged artefacts. For instance, if an archaeologist discovers a fragment of a pottery vessel, AI algorithms can analyse similar pottery styles and designs from the same time period to generate a digital reconstruction of the complete vessel. This not only provides a more comprehensive understanding of the artefact but also offers insights into artistic techniques, trade networks, and cultural exchange.
AI-powered simulations also have the potential to enhance public engagement with archaeology. By creating immersive virtual reality experiences or interactive applications, people can virtually explore reconstructed ancient sites, walk through ancient streets, and interact with virtual inhabitants. This technology brings ancient civilisations to life, making history more accessible and engaging to a wider audience.
However, it is important to note that generative AI in archaeology is not a replacement for traditional archaeological methods. It is a complementary tool that enhances our understanding and visualisation of the past. Human expertise, fieldwork, and careful analysis of archaeological evidence remain crucial in interpreting and contextualisation the insights generated by AI simulations.
Generative AI in archaeology opens up new possibilities for exploring and understanding lost worlds. By harnessing the power of AI algorithms, archaeologists can reconstruct ancient cities, landscapes, and artefacts with a level of detail and accuracy previously unattainable. This technology not only aids in research and interpretation but also enhances public engagement and appreciation of our shared human history. As the field of generative AI continues to advance, we can expect even more remarkable discoveries and insights into the depths of the past.
Serendipity, that delightful phenomenon of stumbling upon something valuable or unexpected by chance, often transcends the boundaries of time and place. In the world of geography, it can unveil a fascinating tapestry of connection between seemingly unrelated locations and discoveries.
One example of the geography of serendipity lies in the story of the spice trade and the exploration of new trade routes during the Age of Discovery. As navigators and explorers set sail in search of exotic spices, they inadvertently encountered new lands and cultures. The pursuit of valuable commodities like cinnamon and pepper led to the discovery of distant lands such as the Americas and the circumnavigation of the globe. The paths of commerce and the hunger for spices brought together people and places in unexpected ways, forever altering the course of history and shaping the world we know today.
Another example can be of course found in the field of archaeology. Often, extraordinary discoveries occur when explorations diverge from their original objectives. China’s famous terracotta warriors, for example (pictured), were only discovered in 1974, when a farmer stumbled on some pottery fragments while in the process of digging a well.
Archaeologists seeking to uncover the remnants of one ancient civilisation may stumble upon the ruins of an entirely different culture, opening a window into a previously unknown chapter of human history. These chance encounters shed light on forgotten civilisations, challenge existing narratives, and offering fresh perspectives on the interconnection of our past.
The geography of serendipity also manifests itself in scientific research. Scientists exploring one field of study may unexpectedly stumble upon connections or phenomena in seemingly unrelated disciplines, leading to groundbreaking discoveries. For instance, the accidental discovery of penicillin by Alexander Fleming, stemming from a contaminated Petri dish, revolutionised the field of medicine.
Serendipity also reveals itself in the natural world, where unique ecological connections and surprising adaptations can be found. Remote and isolated ecosystems, seemingly detached from the rest of the world, often harbour extraordinary species and intricate ecological relationships. Serendipitous encounters with rare and elusive creatures or the discovery of resilient plant species in unexpected habitats remind us of the resilience and adaptability of life.
In unravelling the geography of serendipity, we come to appreciate the profound influence of chance encounters and unexpected connections. It reminds us that the world remains full of hidden surprises, waiting to be uncovered by the curious and open-minded. Serendipity teaches us to embrace the unexpected, to venture beyond the confines of familiar paths, and to embrace the potential for discovery in every corner of our planet.
If you want to read about a recent example of a fortunate, potentially history changing find, follow this link to the BBC website, with a report on a dig in Zambia which has unearthed the possibility that we may have been building our homes a lot earlier than we thought.
The Age of Exploration marks a pivotal era in human history, characterised by intrepid explorers venturing into uncharted territories in search of new lands, riches, and knowledge. This period, spanning from the 15th to the 17th century, witnessed a remarkable surge of maritime expeditions that forever reshaped our understanding of the world. The tales of adventure and discovery created by this epoch continue to captivate our imaginations and inspire a sense of awe for those courageous souls who dared to voyage into the unknown.
One of the most renowned explorers of this era is Christopher Columbus, whose transatlantic journey in 1492 opened the door to the vast, unexplored continents of the Americas. His expedition not only connected Europe with the New World but also paved the way for subsequent explorations, trade routes, and the exchange of goods, ideas, and cultures between East and West. Columbus’ daring voyage ignited a spark of curiosity and ambition that spurred countless others to set sail and seek their own fortunes and adventures across the vast oceans. You can read more about Columbus in another article focused on him – and some of the associated controversies -, here.
Another legendary figure of the Age of Exploration was Ferdinand Magellan, whose expedition in the early 16th century achieved the first circumnavigation of the globe. Magellan’s voyage demonstrated the spherical nature of the Earth and shattered long-held beliefs about the boundaries of the known world. The challenges faced during this historic journey, including treacherous storms, mutinies, and encounters with indigenous cultures, showcased the indomitable spirit and resilience of these explorers, pushing the limits of human achievement.
The Age of Exploration was not limited to the most well-known names like Columbus and Magellan. Countless other intrepid explorers embarked on daring expeditions, each with their own stories of triumph, adversity, and discovery. From Vasco da Gama’s pioneering voyage to find a sea route to India, to James Cook’s epic exploration of the Pacific Ocean, these brave individuals ventured into uncharted waters, navigated treacherous seas, and encountered new lands, peoples, and wildlife previously unknown to the world.
These tales of adventure and discovery from the Age of Exploration continue to inspire us today. They highlight our innate human curiosity and desire to explore, to push the boundaries of our knowledge. They showcase the courage, determination, and resilience of the early explorers who embarked on such perilous journeys with limited navigational tools and technology.
The Age of Exploration brought about profound cultural, scientific, and economic transformation. It facilitated the exchange of goods, ideas, and technologies between different regions of the world, fostering globalisation and reshaping societies. It led to the expansion of colonial empires – for good and ill, the development of new trade routes, and the exploration of new frontiers in science, cartography, and astronomy. They laid the foundation for the advent of the modern world, shaping our understanding of geography, cultures, and the interconnection of nations.
This era continues to inspire, reminding us of the transformative power of exploration. It also serves as testament to the indomitable human spirit and our unyielding quest to uncover the mysteries of the world and expand our horizons.
When we think of future cities, we might picture flying vehicles or space-age architecture, but how will they cope with the growing trend in urbanisation? According to current predictions, more than two-thirds of the world’s population will live in urban areas by 2050. As demand for city living continues, so does the need to create better living conditions and more sustainable environments.
The growing trend in urbanisation has led to a number of challenges, with population growth and migration leading to overcrowding and an increased strain on current resources and infrastructure. Services we take for granted, such as waste disposal or recycling, can often be outdated or ill-equipped to deal with this increased demand.
As the trend for city living increases, so does the cost of housing, potentially leading to an affordability crisis for lower-income residents and a rise in income inequality and crime levels. Urban areas are also a cause for many health concerns. Increasing levels of car ownership and insufficient public transport can lead to high levels of congestion; together with urban construction and industrial activities, this can lead to an increase in air pollution levels. High population densities also encourage the spread of disease and there are growing concerns for the decline in mental health of urban residents compared to those living in rural areas.
Cities are constantly evolving to adapt to challenges like these in an effort to improve the living conditions for their residents. It is highly likely that cities of the future will continue to evolve with the aid of biomimicry, a design approach that takes inspiration from natural elements to develop more sustainable and resilient urban environments. Singapore (pictured) is a great example of how creating green spaces in its urban architecture allows opportunities for sustainability, biodiversity and mental wellbeing, while helping to counter the urban heat island effect.
Cities will become smarter with advancements in technology. The Internet of Things and artificial intelligence will increase the level of automation and optimise services like transportation, energy usage and waste management. As the popularity of autonomous vehicles grows, cities may see a shift away from privately owned vehicles that will help decrease pollution levels, congestion and traffic accidents.
Current urban space constraints may be resolved through vertical expansion, taking advantage of the space high above the ground within cities. Vertical farming techniques will most likely be used to maximise crop yields from a limited land area; this will allow food to be grown near to urban environments and reduce the need for long haul transportation.
From the advancements we can see today to the challenges we have yet to overcome, it’s clear that our cities of the future will have a continued focus on sustainability and resilience. Developing practices such as an urban circular economy will help ensure the preservation of our planet’s resources and address current climate change issues while an enhancement of the quality of life for its residents will improve levels of health and wellbeing. It is therefore vital that governments, businesses and city residents work together in a collaborative effort to help bring about these important changes.
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Perfectionism is not, in and of itself, a negative trait. Perfectionists are often conscientious high achievers; our greatest weakness is also our greatest strength. But those trying to be constantly perfect can find that every task feels like an unconquerable burden and every essay a path to failure, however unlikely our friends and family might find our doom-laden predictions. Here are three thoughts to use to beat the unrealistic idealism that may currently be beating you.
What is perfect, anyway? Maybe you could decide. Perhaps perfection could simply mean sitting down at your messy desk, ignoring the clothes on the floor, and spending 10 minutes planning the first half of your essay. In this deeply imperfect and challenging world, if you were to be reasonable with yourself, your definition of perfect should, and could, be different. Redefine perfection: make it doable and make it your own.
A to-do list is a depressing sight, if, at every item, we are telling ourselves that we ‘have to’ or ‘must’ do this or that. But turn ‘have to’ into ‘get to’ and suddenly life seems more joyful. Perhaps it is an irritating piece of advice, an unwelcome call to simply have more gratitude, but studying is essentially an overwhelmingly positive thing. You are learning and growing, and you have access to great materials and educated teachers; you are lucky. And so, even if it feels at first like you are lying to yourself, tell yourself, next time you inspect your to-do list: “I get to plan my essay today”.
We will do it, but we are waiting for the perfect time when we are in the mood. Because we know we can do it well, and not just well but REALLY well. And so that is the aim. This isn’t laziness, for the fear is real: we cannot bear to submit anything less than our best; we cannot tolerate failure; and we want to be proud of what we have achieved. We have visualised (or we think we have) the perfect essay or assignment. But the truth is that you have a deadline. Perhaps you could achieve perfection if you had eternity to complete it. But you don’t. Most tasks have a timeline, whether it is 6 years to complete a part-time PhD, or one night to finish an essay. And the test is not what you can achieve, but what you can achieve in the time you have to complete it. The definition of perfect might simply be this: finished.
Volcanoes erupt when magma (molten rock) from deep under the earth works its way up through the earth’s mantle and crust, forcing its way through weaker rock, before breaching the surface of the earth. Some eruptions are explosive whilst others ooze lava slowly. An active volcano is defined as one that has erupted within the last 10,000 years and is expected to erupt again. By that definition, there are 1500 active volcanoes in the world today, with three-quarters of them located along the Pacific ‘Ring of Fire’. But active volcanoes don’t necessarily erupt all the time and there are around 50 to 70 volcanic eruptions each year. Let’s take a look at some of the world’s most active volcanoes.
Mount Etna is the largest active volcano in Europe. It first erupted around 500,000 years ago and has been continuously erupting for the past 3500 years. In Greek mythology, Zeus, the ruler or the gods, trapped the one hundred-headed monster, Typhon, beneath the ground. Typhon’s rage at his imprisonment causes rivers of fire to pour out of the mountain. Italy is home to two other active volcanoes – Stromboli, known for its violent bursts of lava, and Mount Vesuvius, the volcano that brought about the destruction of Pompeii in 79 CE.
Found on Hawaii’s Big Island, Kilauea is situated on the south-east slope of the neighbouring volcano, Mauna Loa. Initially it was thought that Kilauea was a satellite of Mauna Loa, but recent research has shown that it has its own system of magma tunnels. The volcano has caused the destruction of much of the surrounding area and so local people often leave flower leis as offerings to the fire goddess Pele who, it is believed, lives in the lava lakes of Kilauea’s Halema’uma’u crater. Mauna Loa, the largest volcano on Earth, is thought to have been erupting continuously for the past 700,000 years.
This volcano caused havoc for the commercial aviation industry in the spring of 2010 when a series of eruptions sent huge clouds of ash into the sky, covering a large area of northern Europe. The eruptions continued from March until June that year forcing 20 countries to close their airspace for a week in April as it was too dangerous to fly, disrupting the travel plans of millions of passengers.
This volcano, thought to have produced more lava flow than any other volcano in the world, also wreaked havoc in 2010 when it began to erupt in October. The series of eruptions continued for weeks, causing the deaths of over 350 people, and leaving thousands more homeless after destroying hundreds of homes. In a 1994 eruption, the volcano claimed the lives of 64 people. It is the most restless of Indonesia’s 130 active volcanoes, with smoke continuously rolling across the mountaintop.
Situated on Ross Island, Mount Erebus is the southernmost of all the world’s active volcanoes and is home to one of the planet’s small number of permanent lava lakes. This volcano is also known for its fumaroles; vents in the Earth’s crust which allow steam and gas to escape, creating huge snow chimneys as the steam instantly freezes.
If you’re interested in learning about the most recent volcanic eruptions, you can view data about them the at the Global Volcanism Program website.