When we think of mountains, we often imagine towering, immovable structures of rock. It may therefore come as a surprise that mountains are actually dynamic, with their height constantly changing due to the natural forces acting on them. Although these changes take place over many years, the height of our mountains can play an important part on our climate and biodiversity.
Tectonic Activity
Mountain growth is primarily driven by Earth’s tectonic plate activity. In a process called continental collision, two plates collide, generating intense pressure and heat that cause the rocks to soften. This force causes the rocks at the point of contact to fold upwards, forming mountain ranges like the Himalayas. In this region, the Indian plate is pushing into the Eurasian plate at a rate of around 5 cm per year, causing the Himalayas to rise by about 1 cm annually.
Another type of tectonic activity, known as subduction, occurs when one plate slides beneath another. As the denser plate sinks, it begins to melt, triggering volcanic activity that leads to the formation of mountain ranges such as the Andes. In this region, the subduction of the denser Nazca plate beneath the South American plate occurs at a rate of 6 to 10 cm per year, causing the Andes to rise by 5 to 10 millimetres annually.
Volcanic Activity
When pressure builds beneath the Earth’s crust, magma can be forced to the surface in an eruption. Over time, the repeated accumulation of magma from volcanic activity leads to the formation of mountains. Volcanic eruptions typically occur at tectonic boundaries, where such pressure is generated.
In contrast, when tectonic plates are pulled apart in a process known as rifting, magma rises to fill the resulting gap, causing mountains to form along the rift. Mount Etna in Italy is one of the world’s most active volcanoes. Each eruption deposits layers of lava and ash that gradually increases the mountain’s height.
Isostatic Rebound
Isostatic rebound occurs when the Earth’s crust adjusts to changes in weight, much like that of a compressed marshmallow regaining its shape. This effect is typically seen when the mass of mountains is reduced due to erosion or the loss of snow and ice. Isostatic rebound helps counteract the decrease in mountain height by allowing the crust to slowly rise and can take place over many years. For example, the melting of glaciers in mountain ranges like the Alps has caused a slight isostatic rebound, with the land gradually lifting several millimetres per year.
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Ash Cloud Formation And Dispersion
Volcanic eruptions are fascinating geological phenomena, but they don’t usually break into the news cycle unless they are spectacular, come with a risk of tsunami, or create an ash cloud that might reach UK airspace.
Though not life-threatening, the recent volcanic eruption near Grindavik, Iceland, in August generated an ash cloud that drifted over the British Isles later that month, receiving extensive media coverage.
Pressure And Particles
But why would a volcanic eruption nearly 900 miles away impact UK airspace? To answer this, we need to understand the science behind volcanic ash cloud formation and dispersion. The magma, or molten rock, that volcanically erupts through the Earth’s crust contains pressurised gases such as sulpher dioxide. Most of this erupting magma spews out as flowing lava on the surface. However, the explosive eruption shreds some of the lava into tiny particles, and the escaping gases launch this material into the air, where it cools down and solidifies into a volcanic ash cloud.
The dispersion patterns of this ash cloud depend on particle size, wind speed and direction, and the type of eruption. The largest particles (around 2mm, about the diameter of a grain of rice) fall closest to the volcano, creating an almost unbreathable atmosphere. The smallest particles are carried by the wind, traveling in whichever direction and at whatever speed the wind moves, and are transported the furthest.
Carried On The Breeze
It is this type of volcanic ash cloud that has been carried south to the UK from Iceland by the prevailing winds. If the eruption is especially large, these volcanic ash particles can be launched into the upper echelons of the atmosphere, where they combine with other dust particles as condensation nuclei. Water vapor condenses around these particles to create clouds, which are then incorporated into the broader atmospheric cloud dispersal process.
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The World’s Most Magnificent Underground Rivers
When we think about magnificent rivers, we think of iconic water flows like The Nile, Congo, and the Amazon rivers, all of which have had movies made about them. However, sometimes, beneath our feet and unknown to us flow a fascinating network of secret underground rivers and wet cave networks, most of which will be unfamiliar. Here are some of the best.
Rio Secreto, Mexico
I must admit, I the first time I hear heard of this one, I simply loved the name, but it is truly magnificent. Located on the Riviera Maya near Playa Del Carmen, this majestic underground water watercourse traverses a limestone cave system which blesses it with magical turquoise waters. One final fact: According to legend, the Rio Secreto was discovered by a local chasing an Iguana!
Tham Khoun Xe River, Laos
The Tham Koun Xe River is 7 km in length with passages reaching 60 metres in height and 80 metres wide at some points. It also features stalagmites over 20 metres high and, allegedly, cave pearls as wide as a ruler. It was discovered in 1905 by Paul Macy, a French Explorer.
Tham Luang Nang Non, Thailand
This river and cave system reached international prominence due to it being the location of the courageous cave rescue of the 12 tourists who had become trapped there due to monsoonal flooding in 2013. But there is a reason tourists come here; it is an epic system, with a gaping main entrance chamber 80 metres in height and traverses 10.3 kilometres of complex winding, narrow tunnels. Tham Luang Non is also seasonal: it has an underground riverbed, but only flows as a river during the Monsoon season.
Ogof Ffynnon Ddu (Cave of the Black Spring), Wales
This is one of the deepest cave systems in the UK with its lowest passageways bottoming out at 274 metres below the surface! It’s a mix of dry and wet caves and contains many ‘thundering river’ passages. It was once also the site of another epic cave rescue involving 300 volunteers.
Sistema Sac Actun (White Cave), Mexico
This claims to be the world’s longest underground river, running 95 miles, and can be found in Quintana Roo, Mexico. Its other claim to fame was the discovery therein, in 2017, of a prehistoric human called Naia, beneath the system along with a mastodon, a prehistoric relative of the Elephant.
Puerto Princesa River, Philippines
This is a UNESCO World heritage site so you can trust this will be beautiful and epic. It’s a 5-mile underground river that can be traversed via an organised canoe trip with the usual stalagmites and stalactites but significant biodiversity including crab-eating Monkeys, white bellied sea eagles and Tabon birds. It seems very family friendly and there seems very little chance of you ‘ending up on the news’ if you know what I mean.
Hang Soong Doong River, Son Doong Cave, Vietnam
Finally, there is Son Doong Cave (pictured) and its river, Hang Soong Doong. This is a place which makes you feel as though you could make some kind of Hollywood fantasy or magical realism epic inside it. It is one of the world’s largest natural caves, containing the fast-flowing subterranean Hang Soong Doong and an extensive network of waterways. The cave interior is so large at points that you could fit an entire New York block inside. The cave also contains its own miniature jungle eco-system, with a layer of mist hovering over it.
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With the Solstice upon us, our thoughts turn to the longest day and the many associated festivals and events that occur around this solar event. Stonehenge, the ancient and mysterious stone circle found in Wiltshire, has become a global focal point for the solstice, with 10,000 people from all over the world visiting it on the 21st of June last year, according to the BBC.
When I am chatting about this event with friends, the inevitable question arises: ‘How were these stone circles made without heavy machinery?’ The answers, while entertaining have often been sketchy so I thought this year, I would see what the experts have to say on the matter!
The Creation Of Stonehenge
The organisation English Heritage has a pretty balanced view on this: they believe that the first monument of Stonehenge was not a great stone, but a circular earthwork enclosure, created around 3000 BCE.
To begin with, a ditch was dug by people with simple deer antler tools, and the chalk was piled up, similarly using people-power to build an inner and outer bank. 56 timber or stone posts (they can’t be sure) were erected in the ditch. This was used as a cremation cemetery until about 2,500 BCE when the site was transformed to form the basis of the monument you see today.
At this point, the enormous Sarsen Stones (weighing 25 tonnes) and smaller bluestones (weighing 2 at 5 tonnes) recognisable today were erected to form a greater monument. Owing to the sheer size and weight of these stones and the mystery of their transportation, many fanciful stories about Giants and wizards were thought up as an explanation.
Science Over Magic
In more recent centuries science has replaced such magic-realism, offering more plausible explanations of the construction process. State-of-the-art geochemical research has confirmed what for years had been suspected; that the Sarsen stones were brought down from the Marlborough Downs (West Woods area) with the efforts of hundreds of well-organised people. The smaller Blue Stones were transported from the Preseli Hills in west Wales. This may sound incredulous but unburdened by modern distractions like TV, the Internet, and theme parks ancient Britons could channel extraordinary levels of human effort into such tasks, allowing them to achieve feats that might seem remarkable by today’s standards.
Construction
The Sarsen and flint hammer-stones found at Stonehenge is believed these to have used to shape and smooth the huge stones we know. There doesn’t seem to be a lot of evidence as to how the stones were erected, but there is a belief that the process started by digging a large hole with a sloping side. The back side of the hole was lined with a row of wooden stakes. Using leverage, strategically placed weights, and an A-Frame and plant fibre ropes, the stone was hoisted and moved into position by the ancient Briton Tug-of-War team! Rubble was packed into the hole to secure the stone. The horizontal lintels were probably raised into position using timber platforms, with tenons then further shaped to securely hold the lintel in place.
So, while we can’t know exactly how Stonehenge was constructed, existing evidence and intelligent guesswork have led to highly plausible construction scenarios.
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The 1st of May marks the anniversary of Scotland’s union with England – a historical event which occurred in 1707. But when and how did Wales and Northern Ireland unite with the UK? Let’s find out.
The UK vs Great Britain
Before we learn about how the countries of England, Wales, Scotland and Ireland united, let’s first clarify the difference between Great Britain and the United Kingdom. These terms are often used interchangeably but they mean quite different things. The country known as The UK, short for the United Kingdom of Great Britain and Northern Ireland, consists of England, Wales, Scotland and Northern Ireland. The ‘British Isles’ refers to all of the islands in the north-western part of the Europe that sit outside the mainland. This includes The Channel Islands, The Isles of Scilly, The Isle of Man and Great Britain amongst many many others. The term ‘Britain’ (a word which derives from the Roman word ‘Britannia’) or ‘Great Britain’ simply refers to the landmass that is the largest island in the British Isles, where England, Wales and Scotland are housed.
Forming The United Kingdom
Now we’ve learnt the correct terminology, let’s delve into a brief history of how Britain and The United Kingdom came to be. It began with the establishment of England. Around 927 CE, Athelstan united the various Anglo-Saxon tribes that lived across the country to form the Kingdom of England. Athelstan became the first King of England.
Fast forward to 1536 when Wales was absorbed into The Kingdom of England. Because he wanted legal and religious unification across his lands, King Henry VIII enacted a bill which meant that Wales would be governed by the same laws as England, effectively making them the same country. Then, in 1707, The Kingdom of England and the Kingdom of Scotland united under the Act of Union and Great Britain was born. It is said that King James I added ‘Great’ to Britain’s name as he wanted to distinguish his new Britain from the Roman Britannia which only consisted of England and some parts of Wales. James I also liked to refer to himself at the King of Great Britain.
Almost a century later in 1801, Ireland also joined the union – creating the United Kingdom of Great Britain and Ireland. But in 1922, the Republic of Ireland (or Eire) withdrew from the union, leaving just the northern counties of Ireland part of the union. And so, the name, as it remains to this day, changed to The United Kingdom of Great Britain and Northern Ireland.
To learn more about the Act of Union and how Scotland became part of Britain, visit Act of Union 1707 – UK Parliament.
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And What Are The 6 Global Hurricane Seasons?
When European explorers travelled to the Caribbean centuries ago they experienced especially violent storms that battered their ships. They would later learn that the local people referred to these storms as hurakan and that for them they signified evil spirits and weather gods.
Three Names
Move forward a few hundred years and a hurakan, now named Hurricane, is only one of three names given to these giant, spiralling tropical storms, that usually have wind speeds of over 74 mph. When they form over the North Atlantic, Central North Pacific, and Eastern North Pacific, they are called Hurricanes, and while the brunt of them usually strike America, their weaker remnants often also hit the UK. However, when such a storm forms over the South Pacific or the Indian Ocean it is referred to as Cyclone, and if it develops in the Northwest Pacific it will be called a Typhoon.
The official Hurricane seasons, followed by their season peak dates are shown below.
1. North Atlantic – June 1 to November 30 (peaks late August to October)
2. Central North Pacific June 1 to November 30 (peaks late August to October)
3. Eastern North Pacific – May 15 to November 30 (peaks in July to September)
4. North West Pacific – N/A as tropical cyclones form throughout the year (peaks late August to early September)
5. Indian Ocean – April 1 to December 31 (peaks May and November)
6. South Pacific – November 1 to April 30 (peaks late February/early March)
Hurricanes originate in warm ocean waters with a surface temperature of over 26.5 degrees. While this temperature is great for swimming, the energy from this warm water also feeds low-pressure weather systems, which are the precursor to storms and eventually hurricanes. The hurricane draws the heat from the warm, moist ocean air and releases it via the condensation of water vapour in thunderstorms. Hurricanes spin around a low-pressure centre known as the eye of the storm which is about 20 to 40 miles wide and is strangely calm. However, it is the wall of this circular eye that contains the strongest winds and most rain.
Hurricanes And Storm Surges
To be honest, if the storm stayed out at sea, the average person wouldn’t know much about it. But, when a Hurricane makes landfall it can often create a huge storm surge, sending seawater flooding inland with great force. In recent times, probably the most infamous of these surges came in the wake of 2005’s Hurricane Katrina, which hit New Orleans and the surrounding coast. Storm surges can create waves that are 20 feet high, and they can move several miles inland to devastating effect. The high winds associated with hurricanes, destructive in themselves, can also create tornadoes to compound the problem.
Thankfully, modern meteorological systems enable hurricanes to be forecast in good time so that people can evacuate to safety until the storm has passed. Such precautions are now more important than ever, as due to climate change creating warmer waters, hurricanes will only become more frequent and more violent.
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We know now that a journey to the centre of the earth would be nowhere near as fantastic as Jules Verne’s depiction, with dinosaurs, secret civilisations and sunken cities. Rather, it would be more like a hi-tech, brute force drilling exercise through gigatonnes of rock, much like what was seen in the 2003 science-fiction disaster movie, The Core. The film depicted a group of scientists who constructed a super drill to take them to the centre of the earth to restart the its core with a nuclear bomb. Well, if a bunch of pioneering scientists really took that journey, this is what they would find…
Journey To The Centre Of The Earth: Mariana To Mantle
Just like in the movie the scientists would probably start the journey at the bottom of the the Mariana Trench in the Pacific Ocean, which at 11km in depth, would cut out a lot of unnecessary drilling. Initially, they would encounter the Earth’s crust. This is the outermost layer of the Earth, ranging from about 20 to 80 kilometres in thickness beneath the continents and about 8 kilometres beneath the ocean floor. This explains why it would make sense to enter the earth through the thinner oceanic crust.
Beneath the crust lies the mantle, a layer of mostly solid rock made of iron, magnesium, and silicon that extends to a depth of approximately 2,900 kilometres. The mantle is dense, hot and semi-solid. and for any pioneering geonauts, they would be drilling through a caramel candy like substance. In the cooler first 200 kilometres of the mantle, they could encounter diamonds in crystalline form.
Outer And Inner Core
The next part of this geological journey to the centre of the earth would be the outer core, which is made of iron and nickel and is in pure liquid form, sitting around 5000 to 3000 kilometres below the surface. It’s heated by the radioactive decay of uranium and thorium, and the liquid churns in a huge turbulent current, which would make for a bumpy ride for any geonaut traversing it. These currents create electrical current and generate the earth’s magnetic field.
Having navigated the radioactive swamp of the outer core our geonauts would now arrive at the Earth’s core proper, the subject of the far-fetched disaster movie I referenced earlier. This is a sold metal sphere made from nickel and iron. With a radius of about 1,200 kilometres it has a temperature of 5,400 degrees Celsius which is almost as hot as the surface of the sun. Pressures here are thought to be 3,000,000 million times greater than on the surface of the earth. It’s mind-blowing! Scientists believe there may be an inner, inner core built of iron and the temperatures and pressures here would be unimaginable!
Such a journey might be purely hypothetical, but it is nonetheless an interesting one to make.
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A Geographical Journey Across Britain’s Blossoming Landscape
The astronomical onset of spring in the UK is marked by the vernal equinox on the 20th of March 2024. However, it may surprise you that there are two additional definitions for the season, stemming from meteorology and phenology (def. The study of cyclical, seasonal phenomena).
When Does Spring Really Begin?
In the Northern Hemisphere, meteorologists typically categorise seasons into three-month intervals determined by average monthly temperatures, with summer being the warmest and winter the coolest. According to this system, spring encompasses the months of March, April, and May, making the 1st of March the meteorological first day of spring.
In practice, establishing precise criteria for the beginning of each season is challenging. For instance, the arrival of spring might be marked by a phonological event like the date of the first daffodil flowers blossoming or the commencement of birds building their nests. However, the specific dates of these phonological events exhibit considerable variation across Britain.
High, Low, Countryside And City
The geographical journey of spring is linked to temperature gradients across Britain. Southern regions experience milder winters, leading to an earlier onset. The gradual increase in temperature triggers key biological processes, such as bud break and flowering, in plant species, marking the first signs of the season. According to studies, spring progresses across the UK at a speed of about 2 mph! So, if you were to walk from Land’s End to John O’Groats, you could likely follow the season—the longest Spring walk ever.
If we are being meticulous, it seems that Spring progresses from southwest to northeast in line with rising temperatures, fuelled no doubt by the warmer southwesterly winds dominating at this time of year.
Altitudinal differences also contribute to the staggered emergence of spring across Britain. The timing of flowering also depends on elevation. Lowland areas generally experience an earlier spring due to milder temperatures. In contrast, higher elevations, such as the Scottish Highlands, maintain winter conditions for a more extended period.
Urban areas introduce microclimates that further affect the timing of spring. Heat-retaining materials, such as concrete and asphalt, create localised warming, leading to an earlier beginning in major cities, compared to surrounding rural landscapes. This urban heat island effect accelerates the blooming of plants and trees in metropolitan areas.
To sum it all up, the geographical journey of spring in Britain is a staggered but overwhelmingly consistent progression from southwest to northeast.
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Understanding the science behind snowfall is deceptively simple: moist air rises, cools, and condenses into ice crystals around particles, forming snowflakes. This process demands freezing temperatures, ample moisture, condensation nuclei, and upward air motion, all abundant during winter. However, predicting snowfall proves to be more elusive.
Why Snowfall In The UK Is So Unpredictable
In many countries, scientists can with some reliability predict when it is going to snow. But, in certain geographies, and we can use the UK as an example, predicting snowfall is not easy. In December 2023, the UK media buzzed with reports of imminent snow in the South of England, yet scientists couldn’t pinpoint when or how much would fall. The reason for this lack of predictability of snowfall in the UK is down to two things, according to Rob Thompson, a Postdoctoral Research Scientist in Meteorology at the University of Reading: “Its location and the fact that small differences in temperature can cause dramatic changes to the forecast.”
Situated at the convergence point of diverse global weather patterns, the UK experiences freezing northern or easterly winds, which occasionally collide with moist air from the west to produce snow. The UK’s awkward predicament stems from the sporadic interaction of northerly/easterly winds with southern warm moist air—a rarity in winter. This tenuous relationship between weather systems makes snowfall hard to anticipate. Moreover, in regions where winter temperatures hover around 0 degrees Celsius, (such as the UK), minor temperature fluctuations wield substantial influence. A two-degree rise transforms falling snow into rain, while a two-degree drop ensures a snowy spectacle.
Even with precise precipitation predictions, the UK’s atmospheric idiosyncrasies make it challenging to forecast the form — rain, sleet, or snow — that precipitation will take. Being a snow weather forecaster in meteorologically awkward regions like the UK is therefore an extremely challenging occupation. Conversely, in regions with consistently colder temperatures, like those at -10 degrees Celsius, snowfall can be predicted with more certainty.
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What is COP?
In 1992, the United Nations Framework Convention on Climate Change (UNFCCC) was founded as an international treaty to address the issue of climate change. The Conference of the Parties, or COP, is the decision-making body of the UNFCCC and brings together representatives from its member countries to discuss and set out actions to tackle climate change. This year, from November the 30th to the 12th of December, will see the latest meeting, COP28, held in the United Arab Emirates.
The main focus of the treaty is to “stabilise greenhouse gas concentrations at a level that would prevent dangerous anthropogenic (human-induced) interference with the climate system”, thereby helping to achieve its goal of limiting long term temperature rises to 1.5C. It aims to achieve this through the promotion of sustainability, equity and justice.
What Has COP Achieved?
Since it’s inception, COP meetings have helped achieve several important milestones. The most significant actions have included the adoption of the Kyoto Protocol at COP3, a legally binding emissions reduction target for developed countries, and perhaps the more widely known Paris Agreement at COP21, which established a global framework for countries to set their own nationally determined contributions (NDCs) to mitigate gas emissions and enhance resilience to climate impacts.
The meetings have so far promoted international cooperation and diplomacy to help foster a sense of shared responsibility, set the stage for global action through global climate goals, provided aid to developing countries’ strategies through financial support and technology transfer, conducted research and innovation and helped raise public awareness. For example, between 2020 and 2025, richer nations have pledged to finance developing countries with $100 billion a year.
Will The UNFCCC Achieve Its Goals?
There is some debate among the public that, ironically, the holding of COP meetings is contributing more to the greenhouse than they are taking away. However, this does assume a negative view the impact of the meetings. In the case of COP28, if its proposals are delivered upon, the emissions savings would prevent 72,200 times more CO2 emissions in 2030 than those associated with the summit itself.
It is true to say, though, that beyond this debate over the summit’s own emissions, there is much more substantial concern surrounding proposal delivery. Many experts agree that despite the efforts being undertaken, especially by major emitters such as the United States and the European Union, the window to achieve the 1.5C target is still narrowing rapidly. Currently it is predicted that global temperatures will reach 2.5C in the near future despite the current pledges to tackle emissions. It is therefore clear that actions being taken need to be increased and at a faster rate.
How COP28 Can Improve Efforts
COP28 aims to address these concerns by fast-tracking the transition to clean energy sources by 2030 and increasing further the financial support for developing countries, to help with their climate action activities. In a world first, the conference aims to push for a phase out of the global use of ‘unabated’ coal, oil and gas. It will also take a first Global Stocktake (GST) of the progress made since the adoption of the Paris Agreement to help decide what measures will be needed to bridge the gap between current progress and climate action targets. This event will, in essence, set the precedent as to whether the UNFCCC can achieve its future targets.
It is clear that COP events have encouraged united collaboration and inspired action on a global scale, placing pressure on businesses and governments to put processes in place to tackle these issues. However, due to the complex nature of the climate actions required and the rate at which climate change is occurring, many challenges still remain.
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