“CH-CH-CH-CH-CHANGES, TURN AND FACE THE STRAIN…”
OVERPOPULATION & CLIMATE CHANGE
|This is a world population growth chart, with extrapolated projections to 2050. Source: U.S. Census Bureau, International Data Base, 10/10/1997.
Credit: Graph is courtesy of the U.S. Census Bureau.
Human population on the Earth has increased dramatically in the last 200 years. From a mere 1 billion people in the year 1800, the number of people rose to over 1.5 billion by 1900, and now has climbed to almost 7 billion today. Some projections estimate that the world population could reach 10.5 billion by the year 2050, which would be a 50% rise in just 40 or so years. This population increase is primarily due to more efficient food-growing and food-distribution technologies as well as new medical advances such as antibiotics. And all of these people, with all of their needs for food, energy, transportation, and goods in our modern mechanized world, are currently straining the world’s resources and drastically affecting world climate. This acceleration cannot be sustained in the long run: famine, drought, disease, warfare, and political turmoil will take their toll on societies living too close to the edge, that have too many people to survive a major catastrophe on a planet with a quickly warming climate, melting glaciers, rising sea levels, and drastic climatic events (such as the ‘epidemic’ we have been experiencing of extreme droughts, terrible hurricanes, and raging floods). Controlling the world’s population and our effect on the Earth’s climate will be major challenges to the human species in the future.
|Global Population and Carbon Dioxide Emissions since 1900. The increase in CO2 emissions since 1900 mirrors almost precisely the human population increase since that time.
Credit: Graph from World Climate Report blog.
Although still a controversial subject in some political arenas, there is growing scientific evidence and overall consensus that the earth’s carbon dioxide levels have risen in the past several decades to alarming levels, and these show no sign of reducing or leveling off in the near future. This rise has been especially dramatic since the Industrial Revolution really got underway in the 1800’s.
|Levels of three major greenhouse gases over the past 200 years, showing the dramatic rise since the Industrial Revolution.
Credit: Graph from https://blogs.reuters.com/environment/2009/03/06/wall-street-journal-of-atmospheric-sciences-reply-to-jenkins/
When scientists have investigated evidence going back even further, to 2000 years ago, the same dramatic and rapid rise can be seen in carbon dioxide and two other major greenhouse gases, methane and nitrous ozide, again, within the last 100 to 200 years compared to the 1,800 years before that.
|Note the incredibly sharp spike in CO2 levels on the Earth since the Industrial Revolution. This spike has produced much greater levels of this greenhouse gas than any of the climate changes during the previous 400,000 years, even during the climatic swings of the Ice Age.
Credit: Graph by Robert A. Rohde, Courtesy of Wikipedia
Then, going back in time even further to 400,000 years ago, the increase in carbon dioxide in just the last 100 to 200 years remains astonishing and alarming. Even compared to the strong oscillations in CO2 that happened during cycles of the Ice Age, increases in CO2 observed after 1900 are a sharp departure, an almost vertical spike way above and beyond anything the Earth experienced for nearly half a million years prior to the Industrial Revolution.
The predicted consequence of this rise in CO2 is global warming: as you read this, glaciers around the world are melting and retreating at an astonishing rate, which will cause rising sea levels. If this were to continue for another century, many of the coastal cities of the world (for example New York, San Francisco, Venice, Hong Kong) will find themselves increasingly inundated by rising sea levels. Overall global warming of course produces many climatic consequences, such as changes in atmospheric and ocean currents and resulting changes in condensation that, along with shifts in air currents, can lead to torrential rains and floods in some regions and droughts in others; the production of tremendous hurricanes and typhoons; even extremely cold winters due to disruptions in atmospheric patterns; and melting of ice packs and glaciers that can threaten water supplies and produce significant increase in sea levels. Overall, this is a chaotic combination of crises that loom on the horizon – and they are largely our own doing.
We sometimes hear skeptics of climate change and global warming say things like “the world’s climate has always been changing”, or that “climate is not really being seriously impacted by humans,” or “even if we are affecting climate, it’s not a big deal or serious threat.” It is getting more and more inescapable, however, that we humans are having a tremendous impact on the Earth’s climate, and that we are inducing serious and extremely rapid global warming.
While it is true that the climate of the Earth has changed over the course of time in the evolution of the Earth, we should remember that in the course of all those changes most species that have ever lived have gone extinct. In the evolution of life forms on the Earth, eventual extinction is the norm. And while the average extinction rate of species in the past has been tallied at around one to five species a year, the species extinction rate now is estimated to have soared to levels 100 to 1000 times the prehistoric average. This is not normal. And as for the human species, never before in the history of the planet have we had so much at stake – an ever-increasing world population of almost seven billion human beings, more than half of these crowded into vulnerable coastal areas subject to hurricanes or typhoons and the threat of flooding by rising sea levels (not to mention tsunamis), and all of them subject to threats of shortages in energy and food and to the ravages of droughts, hurricanes, floods, etc.
When we were hunter-gatherers sparsely populating the Earth, we could more readily adjust to many of the changes in our environment, such as rising sea levels during an interglacial, by moving our camp. Now in the 21st Century, we don’t have that luxury. We are now situated with billions of people spread across the planet and fantastic amounts of accumulated wealth invested in the cities and civilization we have produced. We have a lot more at stake now than ever before in the history of our species, and it is going to require rapid, effective, concerted action across the planet to control the trends we have set forth.
WHY SHOULD I CARE?
This is YOUR world, your only world, and will become the world of your children and grandchildren. Incentives to curb overpopulation and to cut down on the burning of fossil fuels with alternative energy sources are in the earth’s best interest and in your best interest.
Skeptical Science provides scientific information dealing with various comments made by skeptics of global warming. Their byline is “getting skeptical about global warming skepticism,” and they do an excellent job using good reports on science to reveal fallacies in skeptic’s arguments:
Think Progress blog’s discussion of global climate change:
A discussion of global warming in the past 1,000 years:
https://planetforlife.com/gwarm/glob1000.html on the https://planetforlife.com/ website, which presents lots of information on the global energy crisis, the green house effect, sustainable energy, etc.
You can keep track of live ‘clocks’ of the population of the U.S. and the world on this page from the U.S. Census Bureau:
A short video on overpopulation by 2015. I found the interesting aspect to be the idea that as people from the third world move west they will provide the money which will support the elderly in the more developed countries.
This is a counter for the world’s population. I like it because you get to see the rate at which our population grows in real time.
This is an interactive map which details the ‘fingerprints’ and ‘harbingers’ of global warming around the world. I like it because it gives specific locations and how global warming will affect them specifically.