PopulationFirst let’s look at population. The following chart shows the trend for global human population given “business as usual”. That is, if we don’t make fast, fundamental changes then we should expect the following population trend.
census from the WorldBank.The expected human population on Earth will increase. The ongoing question is “By how much?” The trend in the above chart shows a total exceeding 10 billion by 2047. While the above chart doesn’t look concerning, let’s view it from a different timeline. In the following chart we see human population since the dawn of civilization, i.e. about 12,000 years ago. From it we see that we numbered over one billion sometime in the 19th century. Now, we’re well above seven billion. That’s amazing growth.
from wikipedia.As we all know, humans have learned to live in almost any ecosystem. And proliferate! Most striking in the above is that we’ve expanded in numbers and into all regions on Earth in only a few thousand years. That’s quick given the natural pace of change! The following video shows this progress. The UN also provides an estimate on the population for far into the future as shown below. Can you guess at all the assumptions used to make this? From the above chart, there is an expectation, or hope, that our population will start leveling off somewhere above 10 billion people. If it does then we would number over 100 times greater than 5000 years ago. If it doesn’t then what’s the limit?
EnergyEnergy is a critical parameter for our civilization and for the technology that supports our civilization. The following chart shows the recent trend of global per capita primary energy consumption from BP . Are you thinking, “So what.” Well, the above shows a continual increase at a rate greater than population growth. Again, “so what?” Well, we have two main problems related to energy supply. Problem one is that most of our energy today comes from ‘non-renewable resources’ like coal, natural gas and oil. Non-renewable means that they never get replaced and once gone then our energy supply is also gone. Problem two is that releasing the energy from these resources results in serious pollution, mostly airborne. It’s called smog. While smog spoils the view and tastes terrible, it’s worst effect is its alteration of Earth’s atmosphere, leading to climate change. We’ll discuss this more below. Our energy usage keeps going up. The EIA recently indicated that there would likely be a 50% increase in world energy usage by 2050. This increase is great for energy producers. But can the Earth absorb the side effects such as pollutants? And more importantly, will there be sufficient amounts of readily available, clean energy. Our future plans need consider this.
GDPPeople work. We make, bake, create, elate and generally keep busy. Often work gets encapsulated into something called a ‘job’. The job has defined work tasks for which the worker gets paid. We use the pay to purchase items. The flow of money, the economy, can be an indicator of just how much people work to improve our civilization. One measure of the flow of money is the Gross Domestic Product or GDP. The Penn World Table or PWT is the result of one organization’s effort to standardized and measure the global GDP. One of their parameters is the real Gross Domestic Product – national accounts or RGDP NA. This parameter is useful as it normalizes the GDP through time and across the world. The following chart shows the GDP change according to PWT. This chart shows us again that our civilization has been nearly constantly increasing our amount of work or GDP over time. Do you know why? Is it because there are more people working? Or, is it because people are working harder? Or, because our technology makes our tools very expensive? Maybe it’s all the above. Nevertheless, we can use this parameter as it is a very effective demonstration of the amount of work that our civilization produces.
DebtHowever, there is one other important factor regarding the GDP that we must consider when we make plans. That is, we aren’t keeping up with payments. According to the International Monetary Fund (IMF), the global debt ratio is 80% of GDP for public debt and 140% of GDP for private debt. Seems trite perhaps? Well, the value is well above $250 trillion. How do we interpret these debts. Let’s consider. As with any debtor, we are getting the value of the expenditure today while promising to repay the creditor later. The assumption is that in the future we will both want to pay the debt and be able to pay the debt. Is it reasonable to include a plan for a global default? Is it possible that the next generation does not value our investment or want to pay our debt? Would they interpret the debts the same as we do?
InvestmentOne of the benefits of an increasing population is that more people can specialize to advance technology. Their work brings new capability to market such as computation devices. Their work can also improve existing capability such as 3D printers. With research and development, humans have continually advanced way beyond their forebears. The best indicator on investment is a country’s expenditure on research and development. The following chart shows the recent historical trend for this as compiled by the Worldbank. As with other key parameters, the above chart shows a gradual increase. Actually, it’s an increase on an increase because while the percentage of the GDP is increasing, the GDP is also increasing. For 2018, the global expenditure on research and development was estimated at $1.8T. Is this the best amount of investment? And is the investment being allocated in the best way? Planning for the future would ensure that research and development continues and that it is applied appropriately.
Land UseLet’s assume that the Earth’s surface is either land or water. Let’s also assume that the area of each is constant. Now consider humans’ impact upon the land. Up to about 10,000 years ago, people had very little effect; perhaps they had small garden plots and made supper with small cooking fires on land. Today, big change. We’ve laid claim to most of the land surface and we are doing what we want with it. The measured trend of land usage is shown in the following chart.
from Our World in Data.The above chart vividly demonstrates how people have increasingly modified the land surface. It’s to the point where finding untouched lands is a rarity. Can this continue forever? Of course not as the area of land is finite. Can our plans for the future accommodate this? The Food and Agricultural Organization (FAO) of the United Nations keeps an annual assessment of land use. This is useful as from its data we can assess global changes. The following chart shows the total, recent usage when divided into one of three categories; agriculture land use, forestry land and other land. The most significant change is the steady reduction by humans of natural habitat. According to the chart, we’ve lost about 130,000 thousand hectares of forest in 27 years or about 5 million hectares a year. Wow! This loss of natural habitats could continue if it is part of our plan. If so, then will our civilization see to the end of nature?
SustainabilityOne jokester put it that the strongest force known to humans is the force of ‘inertia’. Inertia is when a given state continues unless affected by an outside force. If something were sustainable then it could continue indefinitely unless there were an outside force. Perhaps the age of the dinosaurs was like this. That is, the reptiles could have lived forever on if it weren’t for the meteor that struck at Chichxulub. It was the meteor, the outside force, that ended the sustained 175 million year reign of the dinosaurs. Can humans better this duration? Let’s see if our plans can accomplish this. A derived indicator can highlight our sustainability, or lack thereof. The Ecological Footprint indicator shows whether humans in a given region are taking more than what the ecosystem can provide (a negative value) or taking less (a positive value). The following chart shows a dot for each country. If the dot is positive then the people in the country are living sustainably and may be able to endure as long as the dinosaurs. If the dot is negative then the people in the country are not living sustainably. Note that the above chart has been clipped at a range from [200, -200] gMha. If you look at the data then you will see that the four most negative countries, Japan, India, the United States and China, all have deficits below -500 with China at a Biocapacity Deficit of -3435. gMha. Looking at the data again, you will see that 135 of 189 countries function with a Biocapacity Deficit. These countries amount to over 6 billion people or 86%. This imbalance is highlighted by the Earth Overshoot Day; the day of the year when people stop living sustainably and draw down on the Earth’s biological capital. The overshoot occurs whenever our consumption is greater than what the biocapacity can provide, i.e. a value greater than one in the following chart.
from Footprint NetworkFrom the above, the estimate is that since 1970 we’ve been drawing on the Earth’s capital at a greater rate than the Earth can sustain. Ask yourself, “What’s our plan for the future of civilization when we our lives today consume so much more than what the Earth can continually provide?” Given this draw-down, we’re not going to get close to matching the duration of the dinosaurs.
ClimateThe Biocapacity indicates whether we can live sustainably. But what if the Earth changes thus causing the biocapacity to change? For instance, what if the global temperature increases so much that many hectares of viable land disappear. There is a concern that humans are now causing this and other changes. We’re causing so many change that we’re making a special epoch, the Anthropocene Epoch. Perhaps the next chart showing global temperatures provided by NOAA may get you thinking about sustainability. The above graph shows an increase in the average global temperature. This aligns with the advent of humanity’s industrial revolution. There’s a strong case that on achieving an increase of about 2ºC then the Earth begins a positive temperature feedback. Probably bad times then for most of the ecosystem. And for us. The industrial revolution was the beginning of extensive, continuous air pollution. These pollutants are changing the Earth’s energy balance thus increasing the average global heat thus changing the ecosystem. The next chart shows the trend. Again, we see the values in the chart increasing. One estimate puts the human contribution at about 1.5 trillion tonnes of CO2 equivalent. And these are long lasting air pollutants; which means that their effect goes on for a very long time. For comparison, the estimate for emissions from volcanic activity is 200,000 tons CO2 equivalent.
PollutionIn addition to air pollution, humans generate solid wastes. Most of today’s wastes aren’t readily compostable (e.g. plastics). According to the World Bank, municipalities generate 2.01 billion tonnes of solid waste each year. By 2050 the World Bank estimates the amount to grow to 3.4 billion tonnes.The following chart displays these values assuming a linear trend. What’s the total? It’s almost 95 billion tonnes over 35 years. And its only for the municipalities. Consider all the other sources of solid waste to generate a total waste value for all humans? This waste goes into landfills. Landfills are deleterious to the ecosystem. Should our plans for the future account for ever increasing waste sites like landfills, to the detriment of the local ecosystem, or is there a better option?
SatisfactionAs lamented in a popular song, “I can’t get no satisfaction”. But what exactly is satisfaction? And how does one go around measuring it? This is no simple task and is the basis for so much literature. You can even expand the question and ask “Why am I alive?” We won’t be providing any answers to these questions but we will present one measure of satisfaction. This is the Human Development Index or HDI as calculated by the United Nations. In brief, the index depends upon life expectancy at birth, the years of schooling and gross national income. The following chart presents the HDI for all the countries. Don’t take the above chart as a trend. Rather, consider it as showing the disparity of lifestyles among the people of the world. The weighted mean HDI, by population, is 0.71. That is, about half the people have an HDI below 0.71 and half have a value greater. Let’s consider how we may use the HDI in planning for the future. One reasonable approach is to level the HDI so that everyone is living at a comparable level; all have similar chances to get satisfaction from their lives. And maybe we’ve already identified a path to level the curve, the UN’s Millennium Development Goals. And maybe we just have to keeping work hard to achieve them.
SSPsWe want the best possible future. We may not be sure as to what is the best. Nor are we certain if today’s actions will result in the best. One method to resolve this uncertainty is to consider some general possible futures, both good and bad. We can then identify actions that result in those possible futures. In this, we can estimate the future given our actions today. This method is in use. Five possible futures have been defined to assist with climate change analysis with a focus upon sustainability (i.e. no consequential anthropogenic changes). These are known as the Shared Socioeconomic Pathways (SSPs). Each are described below.
In this SSP, the world’s nations decide to quickly and dramatically avoid exasperating actions leading to climate change. Their policies focus upon a sustainable future, i.e. a future with a climate that is mostly the same as before the industrial revolution.
SSP#2 Avoid Change
In this SSP, the world’s nations aim to continue with actions much as has been occurring but with continual consideration to preventing climate change. Their policies mostly aim at sustaining the old world order.
SSP#3 Us or Them
In this SSP, the world’s nations look to maximizing their benefits. Their policies focus more upon security for their residents than upon the Earth as one ecosystem.
SSP#4 Classes Divided
In this SSP, the world’s nations support stratification. Policies strengthen the power of those that have at the cost of those that have-not.
SSP#5 Full Speed Ahead
In this SSP, the world’s nations focus upon improvements rather than mitigation and remediation. They trust in the free market and the economy to respond to world problems.We will present more on the SSPs as the modeling develops.