Apocalypse: The inevitable end of our civilization
Main blog — 1
Earth is our home. It has been for the past 7 million years and It is now. But will it stay the same in the future? Unfortunately, most scientists and experts consider that an impossible thing. Legendary physicist Stephen Hawking estimates that we have to start leaving Earth within the next 100 years to ensure the survival of humanity. And it's not just him. Many other scientists, billionaires, and activists believe that the future of mankind will not be on the earth. But why do they all believe that? Why are billionaires like Elon Musk and Jeff Bezos investing heavily on rockets and ships that can take us to Mars and Moon? If what they believe is true, where will we go? And how will we do it? When will we have the technology to do that? In this blog series, I will be answering all these questions one by one. And for a start, let’s see why do we have to leave earth or think about planting branches of our civilization on planets other than earth in the first place.
Climate change: The slow poison
Earth becoming uninhabitable and humans being forced to find new homes to ensure survival has always been a hot topic for Hollywood movies and TV shows. Interstellar, After Earth, and Into the Space are some of the most famous works in this genre. And they all talk about the same reasons for ending the World, Global warming, and climate change. And I’m sure that we all have been hearing about it since we started school.
Over the past 50 years, the average global temperature has increased at the fastest rate in human history. And the reason is simple. For centuries, the heat from the sun hit the earth and a portion of it reflects. But the increased presence of CO2 and other greenhouse gases in the atmosphere traps the heat in our atmosphere and causes a gradual temperature rise. This is what is known as the greenhouse effect. In most countries, the burning of fossil fuels like Cole, Petrol, and Diesel are the largest causes of CO2 emission. This includes power plants, vehicles, and generators that burn coal, petrol, and diesel for energy which emits CO2 as a major by-product.
Though closely related to global warming, global climate change is a more accurate or broader term that refers to the process by which the climate system changes such that the earth is not habitable anymore. Climate change has been a ‘hot and controversial topic for decades now. Many people, especially people from the United States, believe that climate change is not real, and is just a conspiracy theory that is created to halt the growth of the United States as it is one of the major countries responsible for rising temperatures. Even Former US president Donald Trump has denied the reality of climate change on various occasions. But the warming oceans and shrinking ice sheets have undeniable evidence now and can not be ignored anymore.
The steady increase in global temperature will cause longer and hotter heat waves and frequent and unexpected droughts. This can seriously affect the agricultural sector as it is vitally connected to the weather patterns in each region. Along with the atmosphere, the temperature of oceans is increasing as well. This can create frequent hurricanes that are stronger than the ones we have ever seen. Rising temperatures will also cause the ice in the north and south poles to melt drastically and sink coastal cities like Florida, Amsterdam, and Mumbai forever. A warmer atmosphere can also cause the formation of smog ( ground-level ozone ) in polluted regions such as Delhi and Beijing. Early and prolonged exposure to smog can increase the risk of lung diseases and decrease the life expectancy of the region.
The biggest threat among all results of global warming and climate change is rather an unfamiliar one. It is the thawing of Permafrost. In simple words, permafrost is just frozen soil found in cold places like tall mountains and poles. Permafrost covers almost 25% of the land area in the northern hemisphere. And near the surface, permafrost also contains large quantities of organic carbon! Yes, the very element that is single-handedly responsible for all the life on the earth and can wipe out the civilization if paired with the ‘wrong’ elements. As the climate warms, permafrost starts to thaw and frees the soil from water ice. This will cause microbes to be active in the soil and decompose the organic materials in it which will result in the emission of greenhouse gases like CO2 and Methane. Right now, permafrost contains almost twice the total amount of carbon that is in the atmosphere. And even if half of that reaches the atmosphere, the results will be catastrophic.
According to the Copenhagen diagnosis which is a report authored by the leading climate scientists of the world, the global temperature can not be expected to stop rising for centuries. It also states that “even a thousand years after reaching a zero-emission society, temperatures will remain elevated, likely cooling down by only a few tenths of a degree below their peak values”. To put it simply, climate change is going to be a big problem for the future generation despite all our efforts to control it.
Death by the hands of humans
Throughout history, civilizations have always collapsed due to man’s greed for power and wealth. The technological advancements we are making in every decade are remarkable. The strength and capabilities of the weapons and machines we have are nothing but magic when you compare them with the weapons we had just 50 years ago. The progress we are making in nuclear physics, bioengineering, robotics, and artificial intelligence is unparalleled such that a single mistake can wipe out the civilization.
Just look at the example of COVID-19 disease. No other pandemic has killed this many people in the age of modern medicine in such a short time. Though it can not end the continuation of humanity, it has definitely planted the seed of fear in all our minds, The fear of extinction!. And the way many countries and leaders treated it makes it even worse. Though the real reasons behind the outbreak of Covid-19 are still not completely known, it is possible to have been caused intentionally or unintentionally by humans. With the biotechnological capabilities we have right now, the idea of an engineered deadly pathogen escaping a lab accidentally is not far-fetched. And if that happens, we wouldn’t be able to stop it.
A nuclear holocaust is another way by which the world can end or be crippled forever such that it is no longer habitable. It is not a secret that many countries possess a huge arsenal of nuclear weapons with immense destruction capabilities. And many more countries are working towards developing their own nuclear weapons secretly. Although there are no accurate estimations on how strong a nuclear weapon should be to be able to eliminate a significant portion of the planet’s population, the detonation of weapons possessed by the USA and Russia alone would be enough to cause a nuclear winter in the entire planet which will destroy the earth’s climate and the way humans live here forever.
Given the risk we are posing to the planet, we may just leave the earth to preserve it for future generations. We are already consuming more resources than the planet can sustain such that petroleum will be only available in research labs and museums after a few generations. World wildlife fund estimates that within 10 years, we will be consuming enough resources that can sustain two Earth-like planets annually. If this continues, then we will need to abandon our current home as our civilization has always done and found new places before the earth runs out of resources. Or atleast, a big part of species will need to be relocated away from here.
A strike from the sky
As a civilization, we have grown to the scale of a spacefaring society. But when you consider the scale of the universe, we are still so tiny and impactless that some of the most common events in outer space can easily endanger humanity.
An asteroid impact is one way that can cause a mass extinction of life on earth. And our planet has already seen one such event. 66 million years ago, a ‘small’ asteroid, roughly 10 Km across hit the earth near the coast of Mexico at a speed of 16–32 Km/s. This resulted in mega-tsunamis all over the world, massive earthquakes, and wildfires, and kicked up enough dust and ashes that blocked the sunlight completely for days and eventually caused the extinction of dinosaurs along with many other plants and animals. If this had not happened, today’s mammals including us probably wouldn’t have existed. There are now over 100 ring-like structures on Earth recognized as impact craters. This suggests that an asteroid strike is not a rare event when you think in a universal scale of time where millions of years is a short period. Scientists at the NASA Ames research center say that an impact by an asteroid larger than 1–2 Km can degrade the global climate and cause widespread crop failure and loss of lives through tsunamis and earthquakes. But such global catastrophes which threaten the existence of humanity takes places only a several time in a few million of years on average. If the asteroid is at least 5 km in width, it can directly mass extinction of all the species on earth.
Though we can never rule out the possibility of the world ending by the above ways, in a strictly mathematical perspective, the chances for it are very slim. But there’s one way by which we know for sure that the planet itself will disintegrate one day. And it will be caused by our life provider, the Sun. Just like any other star, the sun will also have to go through a phase called ‘Red giant’ during its stellar evolution. Currently, the sun is the main sequence star. In cosmic terms, we can consider it as the teenage phase of stars. But within 5.5 billion years from now, the sun will run out of hydrogen in its core which was previously used for nuclear fusion. This will cause gravity to shrink the sun’s core and increase the temperature such that the product formed as a part of earlier hydrogen fusions, that is helium will now start taking part in nuclear fusion to generate energy. This energy will radiate outwards of the core cause the residue hydrogen outside the core to start fusion reaction again and expand the outer layers of the sun. This is when a star is considered a red giant. And during this phase, the expansion of its outer layers will be such that it engulfs all the inner planets, including Earth.
Saving humanity
Dinosaurs were not intelligent creatures. They did not know what was going to happen to them when they saw the asteroid that eventually killed them. The extinction of neanderthals was their inability to adapt to climate change. Other extinct animals and plant species were not intelligent either. They didn’t know what was happening to them. They didn’t know what was going to happen to them. They simply succumbed to one of nature’s great games.
But humans, we are different. We learned to make fire, we learned to farm, we learned to work with metals, we learned to build aircraft, spaceships, missiles, and submarines. We are intelligent. We have always survived existential-level threats nature paused to us using our intelligence. Some by fighting back, some by fleeing, and some by simply accepting the defeat after ensuring a small part of society survive to continue the civilization.
As Dr. Stephen Hawking once said,
“It could be an asteroid hitting the earth, it could be a new virus, climate change, nuclear war, artificial intelligence gone rogue. We can and must use our curiosity and intelligence to look at the stars. And we must do it now before humanity is overtaken by some disaster that we can neither anticipate nor control”.
And scientists have been doing the same for decades now. They have been looking at distant stars and galaxies to find and examine earth-like planets that can one day be a home to us. They have been sending probes and rovers to Mars and the moon to study the possibilities of establishing colonies there such that it can be used for preserving the essence of our civilization as well as transforming them into a hub that can fuel future intergalactic explorations. And what did they all find? To know that, wait for my next blog in which I will discuss the ‘places’ that some of us may call home one day.
References
[1]. Global climate report, National center for environmental information, 2015.
[2]. The Copenhagen Diagnosis: Climate Science Report.
[3]. Coastal risk screening tool, Climate central
[4]. Health effects of air pollution, Health, Government of Canada
[5]. All about the frozen ground, National snow and ice data center
[7]. William K.Hartmann, “The Impact That Wiped Out the Dinosaurs”, Planetary science institute
