Advanced science, Astrophysics, Disasters - natural and man-made, Economic, International

Can humans settle on Mars once Earth becomes uninhabitable?

 In 1920, American poet Robert Frost mused: “Some say the world will end in fire, some say in ice.” Frost held “with those who favour fire.” His poetic view unsurprisingly coincides with mainstream scientific consensus about the real prospect of our own annihilation—arising from the incomprehensible scale of problems baked into our future by human-induced climate change. That is why probably a year before his death in 2018, the celebrated British astrophysicist Stephen Hawking issued a grave warning that we must leave the Earth and colonise “other planets in the next century in order to guarantee survival from a variety of threats.”

Now that the much-hyped COP26 has ended “not with a bang, but with a whimper,” it is time to seriously consider Hawking’s suggestion—colonise another planet before the Earth ends in fire.

From The War of the Worlds by HG Wells to The Martian Way by Isaac Asimov, science fiction writers have long been fascinated by the idea of settling on another planet, especially Mars. Science fiction aside, it is indeed the dream of a growing number of scientists and geo-engineers to make Mars inhabitable with some terraforming, a term used to describe transforming another planet into an Earth-like planet.

Why Mars and not the Moon? The Moon, our nearest neighbour in the sky, is impoverished in resources. Furthermore, a day on the Moon is 29.5 Earth days long. Also, the Moon being far less massive than Earth has a weaker surface gravity—about 16 percent that of Earth. For example, a fully suited Apollo astronaut (equipment included) who weighed about 500 pounds on Earth, weighed only about 80 pounds on the Moon.

Why not other planets? The inner planets, Mercury and Venus, are too hot for humans to survive. The Jovian planets, Jupiter outward to Neptune, are gaseous, which means they do not have solid ground to put our feet on.

What makes Mars, which is on the outer boundary of our solar system’s habitable zone, a good candidate is its proximity from Earth’s closest approach every 15 to 17 years is about 54.6 million kilometres, its day-night cycle is almost the same as ours, with abundant sunshine, and it has a 687-day year with Earth-like four seasons that last twice as long. Although gravity on Mars is 40 percent that of Earth’s, it is sufficiently strong to retain an atmosphere and is believed by many to be adequate for the human body to adapt to. Additionally, hydrologic and volcanic processes on Mars are likely to have consolidated various elements into mineral ores that are of interest to an industrial society.

But current conditions on Mars—freezing cold and bereft of such amenities as a breathable atmosphere—are inhospitable for human beings. Nonetheless, in the ancient past, the Red Planet was remarkably habitable, featuring lakes, rivers and an ocean. Things, however, changed dramatically after the planet lost its magnetic field about four billion years ago when its molten iron core froze up. Without a magnetic field, charged particles in the solar wind stripped away Mars’ once-thick atmosphere, eventually reducing it to a thin sliver that could no longer retain sufficient heat. As a result, the planet underwent a reverse greenhouse effect.

Today, the greenhouse effect on Mars is extremely inefficient. Its atmosphere, about 100 times thinner than Earth’s, is not thick enough to act as a thermal blanket to keep the planet pleasantly warm. Average surface temperature on Mars is a frigid negative 55 degrees Celsius and varies between negative 125 degrees near the poles during winter to positive 20 degrees at the equator during summer. In addition, the atmospheric pressure is less than one percent that of Earth’s. Since the atmosphere is excessively thin and cold, Mars cannot support liquid water on its surface, but this does not mean the planet is devoid of it.

Thus, before we colonise Mars, we have to fix the Martian atmosphere and make it hospitable to human life. In particular, we have to raise the planet’s temperature to a comfortable level and make the atmosphere thicker. Several possible ways of accomplishing this task have been proposed. Among the many techniques that are on the drawing board, scientists are seriously considering adding temperature-raising gases in its atmosphere, to melting parts of the Martian polar ice caps using giant orbiting mirrors to reflect sunlight, to making the Martian surface non-reflective.

Introduction of fluorine-based compounds that produce a greenhouse effect thousands of times stronger than carbon dioxide is being considered as a long-term climate stabiliser. There is also the possibility of in-situ resource utilisation, thanks to NASA’s Curiosity Rover discovering subterranean methane, another potent greenhouse gas.

Another element that could play an important role in trapping heat on Mars is aerogel, one of the lightest materials known to humans. Composed of 99 percent air, it is also a good insulator, which is why it is being used in the Rover mission. Using modelling and experiments that mimicked the Martian surface, researchers from the Harvard University, NASA’s Jet Propulsion Lab and University of Edinburgh demonstrated that a thin layer of this material increased average temperatures of mid-latitudes on Mars to Earth-like temperatures. Aerogel could also be used to build domes for habitation or self-contained biospheres on the surface of Mars.

If large mirrors can successfully be put into orbit, they will reflect sunlight onto Martian poles, so that carbon dioxide and other greenhouse gases that are believed to be trapped inside the ice will melt and initiate the greenhouse effect. The orbital mirror plan has the advantage of continually introducing extra heat into the Martian climate long after the poles have sublimated.

The idea of coating the surface of Mars with dark materials in order to increase the amount of sunlight it absorbs was first proposed by author and scientist Carl Sagan. The materials could be dust from the Martian moons Phobos and Deimos—two of the darkest objects in the Solar System—or extremophile lichens and plants that are dark in colour.

As noted above, Mars does not have a magnetic field strong enough to shield it from the harmful electrically charged particles in solar wind. Scientists at NASA think that it is possible to deflect the solar wind by positioning powerful magnets at one of the five points in space between Mars and the Sun, known as Lagrange Points, where the gravitational forces and the orbital motion of the magnets would interact to create a stable location. Simulations showed that a shield of this sort would protect Mars from the solar wind.

A new study suggests that Mars could be provided with a magnetic field by creating an artificial ring of charged particles around the planet. This could be done by ionising matter on the surface of its moon, Phobos, which orbits the planet quite closely and makes a trip around it every eight hours. The ionised (electrically charged) particles, when accelerated, would generate an electric current that would give rise to a magnetic field strong enough to protect a terraformed Mars.

How soon can Mars be terraformed? Realistically speaking, once technologies are perfected, it would probably take several centuries for the Martian climate to resemble anything even remotely Earth-like. Will our planet remain habitable for such a long time? That is a moot question.

Finally, it is ironic that many of the approaches to terraform Mars represent the global environmental catastrophe currently causing such concern here on Earth. In view of this, opponents consider terraforming Mars to be the ultimate in “cosmic vandalism.” Proponents on the other hand see terraforming as the creation of a new Garden of Eden.

Quamrul Haider is a Professor of Physics at Fordham University, New York.

Advanced science, Astrophysics, International, Technical

Black Holes and the 2020 Nobel Prize in Physics

2020 Physics Nobel Prize winners

Three scientists have been awarded the 2020 Nobel Prize in Physics. They are the British mathematical physicist Roger Penrose, German astrophysicist Reinhard Genzel, and American astronomer Andrea Ghez.

Penrose, a professor at Oxford University, is recognised for his research on black holes carried out in the 1960s. According to the Royal Swedish Academy of Sciences, Penrose has been honoured “for the discovery that black hole formation is a robust prediction of [Albert Einstein’s] general theory of relativity.” Professors Genzel of Max Planck Institute and Ghez of the University of California in Los Angeles were awarded the prize “for the discovery of a supermassive compact object” in a region called Sagittarius A*, located at the centre of our galaxy, The Milky Way.

The criteria for awarding Nobel Prize in Physics are defined in specific terms. Alfred Nobel’s Will stipulates that the prize should be awarded “to the person who made the most important discovery or invention in the field of physics.” The crucial words in the Will are “discovery” and “invention.” It is arguable whether developing a theory can be considered a discovery per se, but it is certainly not an invention in the sense that we normally associate an invention with. That is why the prize is seldom given to theoretical physicists, unless their theory is testable or verifiable.

When theorists won the prize by themselves, for example John Bardeen, Leon Cooper and Robert Schrieffer for their theory of superconductivity, it was for a major theoretical formulation of an existing phenomenon, and thus can be considered as part of the “discovery” of that phenomenon. And theoretical physicists Peter Higgs and François Englert were awarded the Nobel Prize after the particle—Higgs Boson—predicted by their theory to complement the Standard Model of the Universe was experimentally detected.

While the awards to Genzel and Ghez are incontrovertible because they fit Nobel’s criteria quite nicely, Penrose is a rather unusual choice in that his award is not for a discovery. It is for using ingenious mathematical methods to reveal the implications of Einstein’s tour de force—the intimidatingly difficult-to-comprehend Theory of General Relativity.

However, long before Penrose’s prize-winning work on black holes, German physicist Karl Schwarzschild provided the proof of their existence just less than two months after Einstein published the general relativity equations in 1915. By solving the equations exactly, he identified a radius, known as the Schwarzschild radius that defines the horizon or boundary of a voracious gravitational sinkhole—a single point of zero volume and infinite density.

If a massive object could be compressed to fit within the Schwarzschild radius, which is three kilometres per solar mass, no known force could stop it from collapsing into the sinkhole. Today, we call this sinkhole a black hole. His work formed the basis for later studies of black holes, showing that the concentration of matter in a black hole is so great that no light could escape its staggering gravitational pulls, but rather follow a trajectory curving back towards the black hole, thereby making it unobservable.

Lest we forget, Einstein did not win the Nobel Prize for his revolutionary work on general relativity or special relativity. The Nobel Committee decided against them on grounds that the relativity theories were abstract and unproven, although observational proof of general relativity was provided in 1919 by the Cambridge astrophysicist Arthur Eddington. He famously measured the deflection of starlight passing near the Sun during a total solar eclipse. The deflection, known as gravitational lensing, resulted from warping of space, as predicted by general relativity. Instead, Einstein received the deferred 1921 prize in 1922 for his 1905 quantum interpretation of the photoelectric effect because it can be attributed to the discovery of the effect—emission of electrons from metal surfaces under certain illuminations—by the German physicist Heinrich Rudolph Hertz in 1887.

Despite his fame and impact on theoretical physics, Nobel Prize eluded the brilliant physicist, mathematician and cosmologist Stephen Hawking, even though there is a general consensus that he has done more than anyone else since Einstein to deepen our knowledge about the cosmos. As noted by Penrose, a Nobel Prize for Hawking would have been “well-deserved” yet was possibly held back by the committee’s desire to honour observable, rather than theoretical scientific studies that are difficult, or almost impossible, to verify experimentally. Penrose’s work, albeit monumental and worthy of the Nobel Prize, cannot also be experimentally verified because of the very nature of the topics. So why relax requirements for work which are mostly theorems, some hypothesised in collaboration with Hawking?

Penrose is not the first scientist to predict the existence of black holes. The idea of black holes dates back even before Schwarzschild, to 1783, when an English cleric and amateur scientist named John Michell and more than a decade later French mathematician Pierre-Simon Laplace used a thought experiment to explain that light would not leave the surface of a very massive star if the gravitation was sufficiently large. Michell called them “dark stars.”

In 1930, during a long voyage to London, 19-year-old Indian astrophysicist Subrahmanyan Chandrasekhar showed via calculations that when a massive star runs out of fuel, it would blow itself apart in a spectacularly violent explosion into a black hole. He received the Nobel Prize in 1983, not for his work on black holes, but for “studies of the physical processes of importance to the structure and evolution of the stars.”

For decades, the concept of black holes was no more than a mathematical aberration. They are well-nigh impossible to detect because light, one of our cosmic messengers, cannot escape from black holes. Hence, there is a total information blackout. How do we then infer about their existence? As the physics of black holes developed through the years, physicists realised that indirect routes were available. Consequently, our current understanding of black holes is built on inference drawn from data collected by X-ray, optical and radio telescopes.

Indeed, their existence was eventually confirmed in 1971 when astronomers detected a hint of radio wave emissions coming from an object in the constellation Cygnus. The emissions were later interpreted as the fingerprint of the black hole Cygnus X-1. Since then, numerous black holes, including supermassive ones, have been detected in our galaxy and elsewhere in the Universe.

Quamrul Haider is a Professor of Physics at Fordham University, New York.

Astrophysics, Disasters - natural and man-made, Economic, Environmental, International, Life as it is, Technical

Our frontier mentality and the Future of Earth

No one witnessed the birth of Earth. The Earth does not have a birth certificate to authenticate its age. But there is no doubt about Earth’s antiquity. It is 4.55 billion years old. In the context of the Universe which burst into existence 13.7 billion years ago, Earth is in its early middle age. It will live for another five billion years, when the Sun will become a Red Giant, swallowing the nearby planets and ending its luminous career by dwindling into a white dwarf.

Although Earth is very small—a mote of dust—in the vast cosmic arena, it is the only planet that is filled with exquisite beauty, a cornucopia of boisterous wildlife slithering, scampering, soaring and swimming all over the planet. It showcases timeless marvels—a panoply of wonders—sculpted by Nature over millions of years. It is home to towering mountains, alpine glaciers, lush green rainforests, subtropical wilderness and millennia-old humongous trees, gushing geysers, beautiful coral reefs, lofty waterfalls and pristine lakes. The Earth is also home to incredible sandstone arches, deep canyons, varicoloured petrified wood and multi-hued badlands, massive caves filled with imposing stalagmites and stalactites, sparsely vegetated and colourfully painted deserts, gigantic sand dunes, and hundreds of species of flora and fauna.

Evidence of life—bacteria and single-celled organisms—date to 3.85 billion years ago. Since then, life suffered wave after wave of cataclysmic extinctions. The dinosaurs are perhaps the most famous extinct creatures who roamed the Earth’s surface unchallenged during the Mesozoic Era. After surviving for nearly 165 million years, they became victims of the greatest mass deaths in the history of our planet 65 million years ago when a large asteroid hit the Earth.

About 25 million years ago, most of the present day species emerged. Now, fast forward to about two million years ago and we see the evolution of our ancestors—upright, biped, primate mammals. Evidence shows that modern humans originated in Africa within the past 200,000 years, yet there was no move toward high level civilisation. It was the Sumerians of Mesopotamia who developed the world’s first civilisation roughly 6,000 years ago.

We have had the planet to ourselves for a small fraction of time. During this short time interval, we outfoxed other species in the game of survival. Maybe they ran out of luck in evolution’s lottery, or perhaps sometime in the distant past, we became completely dissociated from the checks and balances between man and nature and became a super-predator.

Since the beginning of the Industrial Revolution circa 1760, we made a toxic mess of our natural environment, resulting in an ever-hotter climate, melting glaciers, rising sea levels, widespread droughts, frequent and much wilder storms, crop failures and tens of millions of climate refugees. Our unrestrained use of fossil fuels for more than a century had been slowly pushing the planet toward climatological catastrophe.

Today, we are fixated on enjoying the present and refusing to account for the consequences of our actions on tomorrow. Social scientists interpret this type of behaviour as frontier ethic, prevalent in Western culture as well as others. This ethic embraces a rather narrow view of humans in the environment and even a narrower view of nature. It is characterised by three tenets.

The first is that the Earth has an infinite supply of resources for exclusive human use. There is always more and it is all for us; humans are apart from nature and immune to natural laws; and human success derives from the control of nature.

This tenet no doubt evolved in the prehistoric time when human numbers were small and the Earth’s resources did indeed appear inexhaustible. Not anymore. The massive increase in economic activity and the upsurge in population growth in the last 200 years have brought us face-to-face with the planet’s limitations.

The second tenet sought to position humankind outside the realm of nature. Many people still continue to view human beings as separate from nature and persist in thinking we can do whatever we please without harming the planet. To the contrary, our independence is an illusion, engendered by our remoteness from a world we see through rose-coloured glasses and thermo-paned windows.

As for the third tenet, industrialised nations view nature as a force that must be conquered and subjugated. Hence, we manipulated wildlife, fisheries, land, rivers, oceans and forests like so many pieces in a board game, until the environment reached a dangerous point of disequilibrium.

Over the years, the frontier ethic permeated our lives so much that we became more remote from the natural world outside our artificial environments. It influences our personal goals and expectations without thinking about the effects on the long-term health of the planet.

It cannot be overemphasised that the fate of the planet, our home, and the millions of species that share it with us, as well as the fate of all future generations, lies in our hands. Do we realise that because of resource and ozone depletion, global warming and other problems, the human species will be wiped off the face of the planet if we do not change our lifestyles? At the least, things will deteriorate to the extent that we could lose centuries of technological and economic progress in the next few decades. Our wonderfully diverse biological world, the product of billions of years of evolution, could be eradicated in a fraction of the Earth’s history.

So, what should we do to keep the planet habitable for our future generations? Scientists have urged world leaders in vain to combat global-warming emissions, which have only continued to soar upward. Should we instead rely on a pandemic, such as the coronavirus that is shutting down countries across the globe, slowing down economic activities, halting industrial productions and travel, thereby causing a significant decline in air pollution and carbon/nitrogen emissions all over the world?

The coronavirus pandemic is a tragedy—a palpable human nightmare unfolding in overloaded hospitals with alarming speed, racing toward a horizon darkened by economic disaster and chock-full of signs showing more sufferings to come. This global crisis is also an eye-opener for the other global crisis, the slower one with even higher stakes—anthropogenic climate change.

The cure due to coronavirus is temporary and totally unacceptable, whereas the threat from the adverse effects of climate change will remain with us for years, unless we shape up pronto. Nevertheless, coronavirus should make us wonder if lessons learned from the pandemic might be the beginning of a meaningful shift from business-as-usual attitude.

On this International Mother Earth Day, let us pause for a moment and imagine what the Earth would look like when it will be bereft of mirth, when there will be no wilderness and wildlife, when lakes will be filled with sudsy waters, when coastlines will become unrecognisable and when the air will become a witch’s brew. Can our planet still be called Earth? The answer is no, because we do not have the insight to predict the consequences of our frontier mentality and exercise restraint where we must.

I end the piece with the following words of wisdom from the Native American Chief Seattle. “The Earth does not belong to man, man belongs to the Earth. All things are connected like the blood that unites us all. Man did not weave the web of life, he is merely a strand in it. Whatever he does to the web, he does to himself.”

Quamrul Haider is a Professor of Physics at Fordham University, New York.

Advanced science, Astrophysics, Life as it is, Technical

Quantum Conundrum

The quantum concept that came into existence precisely in the year 1900 was both revolutionary in outlook and spectacular in outcome. This very concept which was put forward by Max Planck in 1900 when he tried to explain black body radiation was subsequently taken up by a luminary like Albert Einstein (as yet unknown to the world) in 1905 and gave a rational explanation to the hitherto difficult scientific problem.

The classical physics (also known as Newtonian physics) was ruling the day until about 1900 when all day-to-day physical problems could be explained by this discipline. But gradually it was running out of steam as new technically challenging phenomena came up due to invention of new instruments and reliable measurements were made.

The intractable physical processes like the black body radiation, interactions of light with particles, the puzzling behaviour of light and many more physical processes could not be explained by traditional classical mechanics. So, a new method, a new mode of thinking, a new science had to be invented that would explain all these inexplicable things.

Although Max Planck was first to venture outside the conventional concept of light being wave in nature to explain ‘black body radiation’ in 1900, it was Albert Einstein who gave scientific explanation by proposing in 1905 the ‘quantisation’ of light – a phenomenon where light was assumed to consist of discreet packets of energy – which he called quantum of light or photon. This quantum of light was advanced in order to explain the hitherto inexplicable photoelectric process, where light was allowed to fall on the surface of a metal and electrons were detected to have emitted. No matter how long or how intense one type of light was, electrons would not be emitted. Only when light of higher frequencies was allowed, electrons were emitted. Einstein showed that photons (quantum of energy in a bundle) of higher frequencies have higher energies and those higher energy photons could emit electrons. (It was like, no matter how long or how heavy the rain is, the roof would not be dented. Only when hailstorm of sufficient big sizes falls on the roof, does the roof cave in). For this quantisation theory, Einstein was awarded Nobel prize in 1921.

Thus, light came to be viewed as both wave and particle, depending on experimental circumstances, and hence the nomenclature ‘wave-particle duality’ came into common vocabulary. If hitherto electromagnetic light can be viewed both as wave and particle, can particles (like electrons) behave like waves? Indeed, so. If electrons are allowed to go through two slits, they interfere and produce alternate bright and dark spectral lines on a screen, exactly like light waves do. The microscopic world does not distinguish between waves and particles, they are blurred into indistinguishable entities. That is the nature that quantum mechanics has produced. 

Although Einstein was the pioneer of quantisation of light, he was not at ease with the way this new concept had been taken up by ‘new lions’ under the stewardship of physicists like Niels Bohr, Wolfgang Pauli, Werner Heisenberg, Erwin Schrodinger, Max Born and many more in the early part of the last century. They collectively produced the full-blown quantum mechanics, which Einstein had difficulty in recognising.  

In quantum theory, particles like electrons revolving round the nucleus of an atom do not exist as particles. They are like strata of waves smeared round the nucleus. However, they exist, behaving like particles, when some energy is imparted to the atom or some energy is taken away from the atom resulting in those electrons moving up or down in energy levels. In other words, electrons exist only when there is an interaction or transition. Without such transitions, electrons just do not show up. However, electrons (with negative charge) are there around the nucleus, but there is no way of telling where the electrons are – only probability of their presence (wave function) can be described! No wonder, Einstein was not happy with such description, which he called incomplete.

Heisenberg produced what came to be known as ‘Heisenberg uncertainty principle’. The elementary particle like an electron cannot be measured with absolute accuracy both its position and momentum at the same time. The act of measuring the position of an electron disturbs the complementary parameter like velocity and so certain amount of uncertainty in momentum creeps in – that is the uncertainty principle. Similar uncertainty exists when measuring time and energy of the particle at the same time.

Niels Bohr, the high priest of quantum mechanics, produced from his Advanced Institute of Physics in Copenhagen, what came to be known as ‘Copenhagen Interpretation’ of quantum mechanics. This interpretation advanced the idea that elementary particles like electrons do not exist in stable or stationary conditions; they only exist in transitions and in interactions.

The ‘Copenhagen Interpretation’ further emphasised that a quantum particle can only be said to exist when it is observed, if it is not observed it does not exist. This was a revolutionary concept. Einstein could not reconcile with that idea. He retorted, “When the Moon is there in the sky, it is real; whether one observes it or not”. Thus, the great intellectual battle on the nature of reality ensued between Einstein and Bohr. Einstein firmly believed that the quantum mechanics as it existed in his life time was inconsistent and incomplete (although he withdrew the ‘inconsistent’ branding, as quantum mechanics kept explaining modern technical processes with consistency). To prove that ‘incompleteness’, he produced various ‘thought experiments’ at various times to challenge Bohr’s ‘Copenhagen Interpretation’. Bohr countered those challenges with technical explanations, but Einstein was not fully convinced.   

Einstein did not like the abstract nature of quantum mechanics. He always demanded that theory must correspond to the reality, if not, it becomes a ‘voodoo’ science.  

For his criticism, he was not very popular with the advocates of ‘Copenhagen Interpretation’. They even lamented that ‘how is it possible that Einstein who was the pioneer of quantum theory and who revolutionised gravitational concept by saying that space is warped by gravity and the gravitational field is indeed the space, now he is reluctant to accept ideas of quantum mechanics’?   

Quantum mechanics had solved many intractable problems and predicted many physical aspects which subsequently came to be true. But at the same time, it is incomprehensible, extremely abstract and devoid of ‘elements of reality’. Anybody hoping to see theory mirroring reality would be totally disappointed. Even Richard Feynman, American Nobel laureate, who contributed significantly to the development of quantum physics once retorted, “I think I can safely say that nobody understands quantum mechanics”! Nonetheless, quantum mechanics is the most advanced scientific discipline of today.

– Dr A Rahman is an author and a columnist.

Advanced science, Astrophysics, Environmental, Technical

How global warming is impacting on Earth’s spin

Anthropogenic greenhouse gas emissions might be affecting more than just the climate. For the first time, scientists at NASA presented evidence that the orientation of the Earth’s spin axis is changing because of global warming.

global_warming_1[1]The Earth spins from west to east about an axis once every 24 hours, creating the continuous cycle of day and night. The north-south spin axis runs through the North and South Poles and is tilted by 23.5 degrees from the vertical. The axial tilt causes almost all the seasonal changes.

But the tilt is far from constant. It varies between 21.6 and 24.5 degrees in a 41,000-year cycle. This variation together with small fluctuations in the Sun and Moon’s gravitational pull, oblate shape and elliptical orbit of the Earth, irregular surface, non-uniform distribution of mass and movement of the tectonic plates cause the spin axis, and hence the Poles, to wobble either east or west along its general direction of drift.

Until 2005, Earth’s spin axis has been drifting steadily in the southwest direction around ten centimetres each year towards the Hudson Bay in Canada. However, in 2005, the axis took an abrupt turn and started to drift east towards England at an annual rate of about 17 centimetres, according to data obtained by NASA’s Gravity Recovery and Climate Experiment satellites. It is still heading east.

After analysing the satellite data, scientists at NASA’s Jet Propulsion Laboratory in California attribute the sudden change in direction of the axis mainly to melting of Greenland’s ice sheets due to global warming. The reason: Melting of ice sheets and the resulting rise of the sea level are changing the distribution of mass on Earth, thereby causing the drift of the spin to change direction and become more oblique. The axis is particularly sensitive to changes in mass distribution occurring north and south of 45 degrees latitude. This phenomenon is similar to the shift in the axis of rotation of a spinning toy if we put more mass on one side of the top or the other.

Since 2002, ice sheets of Greenland have been melting at an annual rate of roughly 270 million tonnes. Additionally, some climate models indicate that a two-to-three degrees Celsius rise in temperature would result in a complete melting of Greenland’s ice sheets. If that happens, it could release the equivalent of as much as 1,400 billion tonnes of carbon dioxide, enhancing global warming even further. It would also raise the sea level by about 7.5 meters. By then, the wobbling of the Poles would also be completely out of whack.

The ice in the Arctic Ocean has also decreased dramatically since the 1960s. For every tonne of carbon dioxide released into the atmosphere, about three square meters of Arctic’s ice were lost in the last 50 years. This reflects a disquieting long-term trend of around ten percent loss of ice per decade. Furthermore, Antarctica is losing more ice than is being replaced by snowfall. The influx of water from the melting of ice of the Arctic Ocean and Antarctica together with the melting of glaciers and the subsequent redistribution of water across the Earth is also causing our planet to pitch over.

What does this mean for us? Although something as small as we humans shook up something as massive as the Earth, it won’t turn upside down as long as the Moon, which acts as a stabiliser of the Earth’s spinning motion, stays in the sky as our nearest neighbour. However, if the shift of the spin axis maintains its present rate and direction, then by the end of this century, the axis would shift by nearly 14 meters. Such a large shift will have devastating consequences for climate change and our planet.

The orientation of the Earth’s spin axis determines the seasonal distribution of radiation at higher latitudes. If the axial tilt is smaller, the Sun does not travel as far north in the sky during summer, producing cooler summers. A larger tilt, as could be in the future, would mean summer days that would be much hotter than the present summer days. In addition, it would impact the accuracy of GPS and other satellite-dependent devices.

Since global warming is causing the Earth’s mass to be redistributed towards the Poles, it would cause the planet to spin faster, just as an ice skater spins faster when she pulls her arms towards her body. Consequently, the length of a day would become shorter.

Our biological clock that regulates sleeping, walking, eating, and other cyclic activities is based on a 24-hour day. Faced with a shorter day, these circadian rhythms would be hopelessly out of sync with the natural world. Moreover, a rapidly spinning Earth will be unstable to the extent that the Poles would wobble faster. This would create enormous stress on the Earth’s geology leading to large-scale natural disasters that will most likely be disastrous for life on Earth.

We may not witness the effects of a rapidly spinning Earth by the end of this century or the next. Nevertheless, the effects will be perceivable a few centuries from now if the global temperature keeps on rising and the ice sheets keep on melting in tandem.

The shift in the Earth’s spin axis due to climate change highlights how real and profoundly large impact humans are having on the planet. The dire consequences of the shift in the axial tilt towards a larger obliquity, as noted above, is not a wake-up call, but an alarm bell. There is still time for our leaders to listen to the scientists and formulate a long-term approach to tackle the problem of climate change instead of a short-term Band-Aid approach, as outlined in the 2015 Paris Agreement, which will see us through only to the end of this century. Therefore, our foremost goal before the death knell should be to reverse global warming, or at the least, to stop further warming instead of limiting it to 1.5-degree in the next 75 years or so.

The author, Quamrul Haider, is a Professor of Physics at Fordham University, New York.